Functionalized perfluorinated polymers and methods of preparation

Abstract

Provided herein are functionalized perfluorinated polymers, each comprising a polymeric chain that comprises two or more repeating units, each repeating unit comprising the structure of Formula (I). Also provided herein are methods of their preparation.

Description

Attorney Docket No.215A001WO01 FUNCTIONALIZED PERFLUORINATED POLYMERS AND METHODS OF PREPARATION CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of the priority of U.S. Provisional Application No.63 / 566,394, filed March 18, 2024; the disclosure of which is incorporated herein by reference in its entirety. FIELD

[0002] Provided herein are functionalized perfluorinated polymers. Also provided herein are methods of their preparation. GOVERNMENT SUPPORT

[0003] This invention was made with government support under Grant No. DE- SC0023982, awarded by the Department of Energy. The government has certain rights in the invention. BACKGROUND

[0004] In the hydrogen energy economy, water electrolysis produces hydrogen fuel in an electrolyzer and the hydrogen fuel is subsequently used in a fuel cell to release electricity and water. Fan et al., Energy Rep.2021, 7, 8421-46. Hydrogen production via water electrolysis provides a viable route to decarbonization, but both an electrolyzer and fuel cell rely on a perfluorinated proton exchange membrane (PEM), primarily made from a costly perfluorinated sulfonic acid (PFSA) ionomer, such as NAFION® and AQUIVION®. Kusoglu and Weber, Chem. Rev.2017, 117, 987-1104. However, a PFSA-PEM lacks recyclability and sustainable end-of-life (EOL) treatment. For example, PFSA ionomers cannot be melt-processed and are not trivial to disperse in a solvent, the two primary methods of polymer processing. A PFSA-PEM is in fact manufactured through the synthesis of a processable thermoplastic precursor that is irreversibly converted to a PFSA ionomer. Id. An EOL PFSA-PEM therefore cannot be thermally reprocessed, generating a significant amount of fluorinated waste and associatedAttorney Docket No.215A001WO01 emissions, including toxic and corrosive HF gas. Therefore, there is a need for reprocessable / recyclable perfluorinated polymers. SUMMARY OF THE DISCLOSURE

[0005] Provided herein is a crosslinked perfluorinated polymer or a salt thereof, wherein the crosslinked perfluorinated polymer comprises two or more polymeric chains, each polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of Formula (I): wherein:the two or more polymeric chains are crosslinked via one or more divalent crosslinkers, each divalent crosslinker having the structure , wherein one A is attached to a repeating unit of aA is attached to a repeating unit of a different polymeric chain at the X position as such that the two X are paired together to form a divalent crosslinker; and free X groups, i.e., the X groups that are not a part of crosslinking, are each independently halo, –OR1a, or –NR1bR1c; each A is independently –O– or ––N(R1b)–; each L is independently a bond, C1-15alkylene, C1-15heteroalkylene, C2-10alkenylene, C2-10 alkynylene, C3-10 cycloalkylene, C6-14 arylene, C7-15 aralkylene, heteroarylene, or heterocyclylene; each R1, R2, R3, and R4is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6alkynyl, C3-6cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; andAttorney Docket No.215A001WO01 each r is independently an integer ranging from about 1 to about 100, in one embodiment, from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)2F, –NReS(O)Rh, –NReS(O)2ORh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2F, –S(O)2Re, –S(O)2ORe, –S(O)NRfRg, andAttorney Docket No.215A001WO01 –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

[0006] Also provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof; comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of:with a compound having the structure of in the presence of a base or a fluoride salt to form the crosslinkedpolymer; wherein: each E is independently –OSi(R5)3 or –NHR1b; each R5is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, R1b, L, Q, m, p, q, and r is as defined herein.

[0007] Additionally provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingof a base or a fluoride salt to form a functionalized polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of:Attorney Docket No.215A001WO01 wherein at least one Xaremaining Xagroups areeach fluoro; and (b) reacting the functionalized polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedwherein: each Laand Lbis independently a bond, C1-15 alkylene, C1-15 heteroalkylene, C2-10 alkenylene, C2-10alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, A, E, Q, m, p, q, and r is as defined herein.

[0008] Furthermore, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingof a base or a fluoride salt to form a functionalized polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: wherein at least one Xaremaining Xagroups are each fluoro;Attorney Docket No.215A001WO01 (b) converting the SO2F groups of the functionalized polymer to sulfonate salt groups with a base; (c) converting the sulfonate salt groups of the functionalized polymer to SO3H groups with an acid; and (d) reacting the functionalized perfluorinated polymer thereafter with a compound having the structure in the presence of a radical initiator to form the crosslinkedwherein each R1, R2, R3, R4, A, E, La, Lb, m, p, q, and r is as defined herein.

[0009] Provided herein is a crosslinked perfluorinated polymer or a salt thereof prepared by a method provided herein.

[0010] Provided herein is a perfluorinated proton exchange membrane comprising a crosslinked perfluorinated polymer or a salt thereof provided herein.

[0011] Provided herein is a pegylated perfluorinated polymer or a salt thereof, wherein the pegylated perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of Formula (I): wherein:at least one X group has the structure of –A–L1–(CH2CH2O)s–Z; and the remaining X groups are each independently halo, –OR1a, or –NR1bR1c; A is –O– or –N(R1b)–; L1is a bond, C1-15 alkylene, C1-15 heteroalkylene, C2-10 alkenylene, C2-10 alkynylene, C3-10 cycloalkylene, C6-14 arylene, C7-15 aralkylene, heteroarylene, or heterocyclylene; Z is hydrogen, C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl,Attorney Docket No.215A001WO01 C2-6 alkynyl, C3-6 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; and each s is independently an integer of ranging from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf,Attorney Docket No.215A001WO01 –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)2F, –NReS(O)Rh, –NReS(O)2ORh, –NReS(O)NRfRg, (ii)or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

[0012] Provided herein is a method of preparing a pegylated perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingthe presence of a base or a fluoride salt to form the pegylated perfluorinated polymer; wherein each E, L1, Z, m, p, q, and s is as defined herein.

[0013] Provided herein is a pegylated perfluorinated polymer or a salt thereof prepared by a method provided herein.

[0014] Provided herein is a perfluorinated proton exchange membrane comprising a pegylated perfluorinated polymer or a salt thereof provided herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0001] FIG.1 depicts an FT-IR spectrum of a crosslinked NAFION-SO2F, along with FT-IR spectra of the corresponding starting materials, a polysiloxane crosslinker and unmodified NAFION-SO2F.

[0002] FIG.2 depicts a differential scanning calorimetry (DSC) thermogram of a crosslinked NAFION-SO2F having a degree of crosslinking (DC) of about 6%, along with a DSC thermogram of the corresponding unmodified NAFION-SO2F.Attorney Docket No.215A001WO01

[0003] FIG.3 depicts FT-IR spectra of a crosslinked NAFION-SO2F and crosslinked NAFION-SO3H each having a DC of about 20%, along with a FT-IR spectrum of the corresponding unmodified NAFION-SO2F.

[0004] FIG.4 depicts a DSC thermogram of a crosslinked NAFION-SO3H having a DC of about 6%, along with a DSC thermogram of the corresponding unmodified NAFION-SO3H.

[0005] FIG.5 depicts an FT-IR spectrum of a pegylated NAFION-SO2F, along with FT-IR spectra of the corresponding starting materials, a PEG-NH2and unmodified NAFION-SO2F.

[0006] FIG.6 depicts a DSC thermogram of a pegylated NAFION-SO2F having a grafting density in percentage of about 20%, along with a DSC thermogram of the corresponding unmodified NAFION-SO2F.

[0007] FIG.7 depicts FT-IR spectra of a pegylated NAFION-SO2F and pegylated NAFION- SO3H each having a grafting density in percentage of about 20%, along with FT-IR spectrum of the corresponding unmodified NAFION-SO3H.

[0008] FIG.8 depicts a DSC thermogram of a pegylated NAFION-SO3H having a grafting density in percentage of about 20%, along with a DSC thermogram of the corresponding unmodified NAFION-SO3H. DETAILED DESCRIPTION

[0015] To facilitate understanding of the disclosure set forth herein, a number of terms are defined below.

[0016] Generally, the nomenclature used herein and the laboratory procedures in electrochemistry, organic chemistry, and polymer chemistry described herein are those well- known and commonly employed in the art. Unless defined otherwise, all technical and scientific terms used herein generally have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0017] The term “about” or “approximately” means an acceptable error for a particular value as determined by one of ordinary skill in the art, which depends in part on how the value isAttorney Docket No.215A001WO01 measured or determined. In certain embodiments, the term “about” or “approximately” means within 1, 2, or 3 standard deviations. In certain embodiments, the term “about” or “approximately” means within 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.05% of a given value or range.

[0018] The term “alkyl” refers to a linear or branched saturated monovalent hydrocarbon radical, wherein the alkyl is optionally substituted with one or more substituents Q as described herein. For example, C1-6alkyl refers to a linear saturated monovalent hydrocarbon radical of 1 to 6 carbon atoms or a branched saturated monovalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the alkyl is a linear saturated monovalent hydrocarbon radical that has 1 to 20 (C1-20), 1 to 15 (C1-15), 1 to 10 (C1-10), or 1 to 6 (C1-6) carbon atoms, or branched saturated monovalent hydrocarbon radical of 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6 (C3-6) carbon atoms. As used herein, linear C1-6 and branched C3-6 alkyl groups are also referred as “lower alkyl.” Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl (including all isomeric forms, e.g., n-propyl and isopropyl), butyl (including all isomeric forms, e.g., n-butyl, isobutyl, sec-butyl, and t-butyl), pentyl (including all isomeric forms, e.g., n- pentyl, isopentyl, sec-pentyl, neopentyl, and tert-pentyl), and hexyl (including all isomeric forms, e.g., n-hexyl, isohexyl, and sec-hexyl).

[0019] The terms “alkylene” and “alkanediyl” are used interchangeably herein in reference to a linear or branched saturated divalent hydrocarbon radical, wherein the alkanediyl is optionally substituted with one or more substituents Q as described herein. For example, C1-6alkanediyl refers to a linear saturated divalent hydrocarbon radical of 1 to 6 carbon atoms or a branched saturated divalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the alkanediyl is a linear saturated divalent hydrocarbon radical that has 1 to 30 (C1-30), 1 to 20 (C1-20), 1 to 15 (C1-15), 1 to 10 (C1-10), or 1 to 6 (C1-6) carbon atoms, or branched saturated divalent hydrocarbon radical of 3 to 30 (C3-30), 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6 (C3-6) carbon atoms. As used herein, linear C1-6and branched C3-6alkanediyl groups are also referred as “lower alkanediyl.” Examples of alkanediyl groups include, but are not limited to, methanediyl, ethanediyl (including all isomeric forms, e.g., ethane-1,1-diyl and ethane-1,2- diyl), propanediyl (including all isomeric forms, e.g., propane-1,1-diyl, propane-1,2-diyl, and propane-1,3-diyl), butanediyl (including all isomeric forms, e.g., butane-1,1-diyl, butane-1,2-diyl,Attorney Docket No.215A001WO01 butane-1,3-diyl, and butane-1,4-diyl), pentanediyl (including all isomeric forms, e.g., pentane- 1,1-diyl, pentane-1,2-diyl, pentane-1,3-diyl, and pentane-1,5-diyl), and hexanediyl (including all isomeric forms, e.g., hexane-1,1-diyl, hexane-1,2-diyl, hexane-1,3-diyl, and hexane-1,6-diyl). Examples of substituted alkanediyl groups include, but are not limited to, –C(O)CH2–, –C(O)(CH2)2–, –C(O)(CH2)3–, –C(O)(CH2)4–, –C(O)(CH2)5–, –C(O)(CH2)6–, –C(O)(CH2)7–, –C(O)(CH2)8–, –C(O)(CH2)9–, –C(O)(CH2)10–, –C(O)CH2C(O)–, –C(O)(CH2)2C(O)–, –C(O)(CH2)3C(O)–, –C(O)(CH2)4C(O)–, or –C(O)(CH2)5C(O)–.

[0020] The term “heteroalkyl” refers to a linear or branched saturated monovalent hydrocarbon radical that contains one or more heteroatoms on its main chain, each independently selected from O, S, and N. The heteroalkyl is optionally substituted with one or more substituents Q as described herein. For example, C1-6 heteroalkyl refers to a linear saturated monovalent hydrocarbon radical of 1 to 6 carbon atoms or a branched saturated monovalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the heteroalkyl is a linear saturated monovalent hydrocarbon radical that has 1 to 20 (C1-20), 1 to 15 (C1-15), 1 to 10 (C1-10), or 1 to 6 (C1-6) carbon atoms, or branched saturated monovalent hydrocarbon radical of 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6 (C3-6) carbon atoms. As used herein, linear C1-6and branched C3-6heteroalkyl groups are also referred as “lower heteroalkyl.” Examples of heteroalkyl groups include, but are not limited to, –OCH3, –OCH2CH3, –CH2OCH3, –NHCH3, –ONHCH3, –NHOCH3, –SCH3, –CH2NHCH2CH3, and –NHCH2CH2CH3. Examples of substituted heteroalkyl groups include, but are not limited to, –CH2NHC(O)CH3and –NHC(O)CH2CH3.

[0021] The terms “heteroalkylene” and “heteroalkanediyl” are used interchangeably herein in reference to a linear or branched saturated divalent hydrocarbon radical that contains one or more heteroatoms in its main chain, each independently selected from O, S, and N. The heteroalkylene is optionally substituted with one or more substituents Q as described herein. For example, C1-6heteroalkylene refers to a linear saturated divalent hydrocarbon radical of 1 to 6 carbon atoms or a branched saturated divalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the heteroalkylene is a linear saturated divalent hydrocarbon radical that has 1 to 20 (C1-20), 1 to 15 (C1-15), 1 to 10 (C1-10), or 1 to 6 (C1-6) carbon atoms, or branched saturated divalent hydrocarbon radical of 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6Attorney Docket No.215A001WO01 (C3-6) carbon atoms. As used herein, linear C1-6 and branched C3-6 heteroalkylene groups are also referred as “lower heteroalkylene.” Examples of heteroalkylene groups include, but are not limited to, –CH2O–, –CH2CH2O–, –CH2CH2CH2O–, –(CH2)4O–, –(CH2)5O–, –(CH2)6O–, –(CH2)7O–, –(CH2)8O–, –(CH2)9O–, –(CH2)10O–, –CH2OCH2–, –CH2CH2O–, –(CH2CH2O)2–, –(CH2CH2O)3–, –(CH2CH2O)4–, –(CH2CH2O)5–, –CH2NH–, –CH2NHCH2–, –CH2CH2NH–, – CH2CH2CH2NH–, –(CH2)4NH–, –CH2S–, –CH2SCH2–, and –CH2CH2S–. Examples of substituted heteroalkylene groups include, but are not limited to, –C(O)CH2O–, –C(O)(CH2)2O–, –C(O)CH2CH2CH2O–, –C(O)CH2CH2CH2CH2O–, –C(O)(CH2)5O–, –C(O)(CH2)6O–, –C(O)(CH2)7O–, –C(O)(CH2)8O–, –C(O)(CH2)9O–, –C(O)(CH2)10O–, –C(O)CH2OCH2CH2O–, –C(O)CH2O(CH2CH2O)2–, –C(O)CH2O(CH2CH2O)3–, –C(O)CH2O(CH2CH2O)4, –C(O)CH2O(CH2CH2O)5–, –CH2NHC(O)CH2–, –CH2CH2C(O)NH–, –CH2N(CH3)–, –(CH2)2N(CH3)–, –(CH2)3N(CH3)–, or –(CH2)4N(CH3)–.

[0022] The term “alkenyl” refers to a linear or branched monovalent hydrocarbon radical, which contains one or more, in one embodiment, one, two, three, or four, in another embodiment, one, carbon-carbon double bond(s). The alkenyl is optionally substituted with one or more substituents Q as described herein. The term “alkenyl” embraces radicals having a “cis” or “trans” configuration or a mixture thereof, or alternatively, a “Z” or “E” configuration or a mixture thereof, as appreciated by those of ordinary skill in the art. For example, C2-6 alkenyl refers to a linear unsaturated monovalent hydrocarbon radical of 2 to 6 carbon atoms or a branched unsaturated monovalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the alkenyl is a linear monovalent hydrocarbon radical of 2 to 20 (C2-20), 2 to 15 (C2-15), 2 to 10 (C2-10), or 2 to 6 (C2-6) carbon atoms, or a branched monovalent hydrocarbon radical of 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6 (C3-6) carbon atoms. Examples of alkenyl groups include, but are not limited to, ethenyl, propenyl (including all isomeric forms, e.g., propen-1-yl, propen-2-yl, and allyl), and butenyl (including all isomeric forms, e.g., buten- 1-yl, buten-2-yl, buten-3-yl, and 2-buten-1-yl).

[0023] The terms “alkenylene” and “alkenediyl” are used interchangeably herein in reference to a linear or branched divalent hydrocarbon radical, which contains one or more, in one embodiment, one, two, three, or four, in another embodiment, one, carbon-carbon double bond(s). The alkenediyl is optionally substituted with one or more substituents Q as describedAttorney Docket No.215A001WO01 herein. The term “alkenediyl” embraces radicals having a “cis” or “trans” configuration or a mixture thereof, or alternatively, a “Z” or “E” configuration or a mixture thereof, as appreciated by those of ordinary skill in the art. For example, C2-6alkenediyl refers to a linear unsaturateddivalent hydrocarbon radical of 2 to atoms or a branched unsaturated divalent hydrocarbon radical of 3 to 6 carbon atoms. In certain embodiments, the alkenediyl is a linear divalent hydrocarbon radical of 2 to 30 (C2-30), 2 to 20 (C2-20), 2 to 15 (C2-15), 2 to 10 (C2-10), or 2 to 6 (C2-6) carbon atoms, or a branched divalent hydrocarbon radical of 3 to 30 (C3-30), 3 to 20 (C3-20), 3 to 15 (C3-15), 3 to 10 (C3-10), or 3 to 6 (C3-6) carbon atoms. Examples of alkenediyl groups include, but are not limited to, ethenediyl (including all isomeric forms, e.g., ethene-1,1- diyl and ethene-1,2-diyl), propenediyl (including all isomeric forms, e.g., 1-propene-1,1-diyl, 1- propene-1,2-diyl, and 1-propene-1,3-diyl), butenediyl (including all isomeric forms, e.g., 1- butene-1,1-diyl, 1-butene-1,2-diyl, and 1-butene-1,4-diyl), pentenediyl (including all isomeric forms, e.g., 1-pentene-1,1-diyl, 1-pentene-1,2-diyl, and 1-pentene-1,5-diyl), and hexenediyl (including all isomeric forms, e.g., 1-hexene-1,1-diyl, 1-hexene-1,2-diyl, 1-hexene-1,3-diyl, 1- hexene-1,4-diyl, 1-hexene-1,5-diyl, and 1-hexene-1,6-diyl).

[0024] The term “alkynyl” refers to a linear or branched monovalent hydrocarbon radical, which contains one or more, in one embodiment, one, two, three, or four, in another embodiment, one, carbon-carbon triple bond(s). An alkynyl group does not contain a carbon-carbon double bond. The alkynyl is optionally substituted with one or more substituents Q as described herein. For example, C2-6alkynyl refers to a linear unsaturated monovalent hydrocarbon radical of 2 to 6 carbon atoms or a branched unsaturated monovalent hydrocarbon radical of 4 to 6 carbon atoms. In certain embodiments, the alkynyl is a linear monovalent hydrocarbon radical of 2 to 20 (C2-20), 2 to 15 (C2-15), 2 to 10 (C2-10), or 2 to 6 (C2-6) carbon atoms, or a branched monovalent hydrocarbon radical of 4 to 20 (C4-20), 4 to 15 (C4-15), 4 to 10 (C4-10), or 4 to 6 (C4-6) carbon atoms. Examples of alkynyl groups include, but are not limited to, ethynyl (–C≡CH), propynyl (including all isomeric forms, e.g., 1-propynyl (–C≡CCH3) and propargyl (–CH2C≡CH)), butynyl (including all isomeric forms, e.g., 1-butyn-1-yl and 2-butyn-1-yl), pentynyl (including all isomeric forms, e.g., 1-pentyn-1-yl and 1-methyl-2-butyn-1-yl), and hexynyl (including all isomeric forms, e.g., 1-hexyn-1-yl and 2-hexyn-1-yl).

[0025] The terms “alkynylene” and “alkynediyl” are used interchangeably herein inAttorney Docket No.215A001WO01 reference to a linear or branched divalent hydrocarbon radical, which contains one or more, in one embodiment, one, two, three, or four, in another embodiment, one, carbon-carbon triple bond(s). An alkynylene group does not contain a carbon-carbon double bond. The alkynediyl is optionally substituted with one or more substituents Q as described herein. For example, C2-6 alkynediyl refers to a linear unsaturated divalent hydrocarbon radical of 2 to 6 carbon atoms or a branched unsaturated divalent hydrocarbon radical of 4 to 6 carbon atoms. In certain embodiments, the alkynediyl is a linear divalent hydrocarbon radical of 2 to 30 (C2-30), 2 to 20 (C2-20), 2 to 15 (C2-15), 2 to 10 (C2-10), or 2 to 6 (C2-6) carbon atoms, or a branched divalent hydrocarbon radical of 4 to 30 (C4-30), 4 to 20 (C4-20), 4 to 15 (C4-15), 4 to 10 (C4-10), or 4 to 6 (C4-6) carbon atoms. Examples of alkynediyl groups include, but are not limited to, ethynediyl, propynediyl (including all isomeric forms, e.g., 1-propyne-1,3-diyl and 1-propyne-3,3-diyl), butynediyl (including all isomeric forms, e.g., 1-butyne-1,3-diyl, 1-butyne-1,4-diyl, and 2- butyne-1,1-diyl), pentynediyl (including all isomeric forms, e.g., 1-pentyne-1,3-diyl, 1-pentyne- 1,4-diyl, and 2-pentyne-1,1-diyl), and hexynediyl (including all isomeric forms, e.g., 1-hexyne- 1,3-diyl, 1-hexyne-1,4-diyl, and 2-hexyne-1,1-diyl).

[0026] The term “cycloalkyl” refers to a cyclic monovalent hydrocarbon radical, which is optionally substituted with one or more substituents Q as described herein. In one embodiment, the cycloalkyl is a saturated or unsaturated but non-aromatic, and / or bridged or non-bridged, and / or fused and / or spiro bicyclic group. In certain embodiments, the cycloalkyl has from 3 to 20 (C3-20), from 3 to 15 (C3-15), from 3 to 10 (C3-10), or from 3 to 7 (C3-7) carbon atoms. In one embodiment, the cycloalkyl is monocyclic. In another embodiment, the cycloalkyl is bicyclic. In yet another embodiment, the cycloalkyl is tricyclic. In still another embodiment, the cycloalkyl is polycyclic. Examples of cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cyclohexadienyl, cycloheptyl, cycloheptenyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.1]hexyl, bicyclo[2.2.1]heptyl, bicyclo[2.2.2]octyl, decalinyl, and adamantyl.

[0027] The terms “cycloalkylene” and “cycloalkanediyl” are used interchangeably herein in reference to a cyclic divalent hydrocarbon radical, which may be optionally substituted with one or more substituents Q as described herein. In one embodiment, cycloalkanediyl groups may be saturated or unsaturated but non-aromatic, and / or bridged, and / or non-bridged, and / or fusedAttorney Docket No.215A001WO01 bicyclic groups. In certain embodiments, the cycloalkanediyl has from 3 to 30 (C3-30), 3 to 20 (C3-20), from 3 to 15 (C3-15), from 3 to 10 (C3-10), or from 3 to 7 (C3-7) carbon atoms. Examples of cycloalkanediyl groups include, but are not limited to, cyclopropanediyl (including all isomeric forms, e.g., cyclopropane-1,1-diyl and cyclopropane-1,2-diyl), cyclobutanediyl (including all isomeric forms, e.g., cyclobutane-1,1-diyl, cyclobutane-1,2-diyl, and cyclobutane- 1,3-diyl), cyclopentanediyl (including all isomeric forms, e.g., cyclopentane-1,1-diyl, cyclopentane-1,2-diyl, and cyclopentane-1,3-diyl), cyclohexanediyl (including all isomeric forms, e.g., cyclohexane-1,1-diyl, cyclohexane-1,2-diyl, cyclohexane-1,3-diyl, and cyclohex-1,4-diyl), cycloheptanediyl (including all isomeric forms, e.g., cycloheptane-1,1-diyl, cycloheptane-1,2- diyl, cycloheptane-1,3-diyl, and cycloheptane-1,4-diyl), decalinediyl (including all isomeric forms, e.g., decaline-1,1-diyl, decaline-1,2-diyl, and decaline-1,8-diyl), and adamantdiyl (including all isomeric forms, e.g., adamant-1,2-diyl, adamant-1,3-diyl, and adamant-1,8-diyl).

[0028] The term “aryl” refers to a monovalent monocyclic aromatic hydrocarbon radical and / or monovalent polycyclic aromatic hydrocarbon radical that contain at least one aromatic carbon ring. In certain embodiments, the aryl has from 6 to 20 (C6-20), from 6 to 15 (C6-15), or from 6 to 10 (C6-10) ring carbon atoms. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, fluorenyl, azulenyl, anthryl, phenanthryl, pyrenyl, biphenyl, and terphenyl. The aryl also refers to bicyclic or tricyclic carbon rings, where one of the rings is aromatic and the others of which may be saturated, partially unsaturated, or aromatic, for example, dihydronaphthyl, indenyl, indanyl, or tetrahydronaphthyl (tetralinyl). In one embodiment, the aryl is monocyclic. In another embodiment, the aryl is bicyclic. In yet another embodiment, the aryl is tricyclic. In still another embodiment, the aryl is polycyclic. In certain embodiments, the aryl is optionally substituted with one or more substituents Q as described herein.

[0029] The terms “arylene” and “arenediyl” are used interchangeably herein in reference to a divalent monocyclic aromatic hydrocarbon radical or divalent polycyclic aromatic hydrocarbon radical that contains at least one aromatic hydrocarbon ring. In certain embodiments, the arylene has from 6 to 20 (C6-20), from 6 to 15 (C6-15), or from 6 to 10 (C6-10) ring atoms. Examples of arylene groups include, but are not limited to, phenylene (including all isomeric forms, e.g., phen-1,2-diyl, phen-1,3-diyl, and phen-1,4-diyl), naphthylene (including all isomeric forms, e.g., naphth-1,2-diyl, naphth-1,3-diyl, and naphth-1,8-diyl), fluorenyleneAttorney Docket No.215A001WO01 (including all isomeric forms, e.g., fluoren-1,2-diyl, fluoren-1,3-diyl, and fluoren-1,8-diyl), azulenylene (including all isomeric forms, e.g., azulen-1,2-diyl, azulen-1,3-diyl, and azulen-1,8- diyl), anthrylene (including all isomeric forms, e.g., anthr-1,2-diyl, anthr-1,3-diyl, and anthr-1,8- diyl), phenanthrylene (including all isomeric forms, e.g., phenanthr-1,2-diyl, phenanthr-1,3-diyl, and phenanthr-1,8-diyl), pyrenylene (including all isomeric forms, e.g., pyren-1,2-diyl, pyren- 1,3-diyl, and pyren-1,8-diyl), biphenylene (including all isomeric forms, e.g., biphen-2,3-diyl, biphen-3,4’-diyl, and biphen-4,4’-diyl), and terphenylene (including all isomeric forms, e.g., terphen-2,3-diyl, terphen-3,4’-diyl, and terphen-4,4’-diyl). Arylene also refers to bicyclic or tricyclic carbon rings, where one of the rings is aromatic and the others of which may be saturated, partially unsaturated, or aromatic, for example, dihydronaphthylene (including all isomeric forms, e.g., dihydronaphth-1,2-diyl and dihydronaphth-1,8-diyl), indenylene (including all isomeric forms, e.g., inden-1,2-diyl, inden-1,5-diyl, and inden-1,7-diyl), indanylene (including all isomeric forms, e.g., indan-1,2-diyl, indan-1,5-diyl, and indan-1,7-diyl), or tetrahydronaphthylene (tetralinylene) (including all isomeric forms, e.g., tetrahydronaphth-1,2- diyl, tetrahydronaphth-1,5-diyl, and tetrahydronaphth-1,8-diyl). In certain embodiments, arylene is optionally substituted with one or more substituents Q as described herein.

[0030] The term “aralkyl” or “arylalkyl” refers to a monovalent alkyl group substituted with one or more aryl groups. In certain embodiments, the aralkyl has from 7 to 30 (C7-30), from 7 to 20 (C7-20), or from 7 to 16 (C7-16) carbon atoms. Examples of aralkyl groups include, but are not limited to, benzyl, phenylethyl (including all isomeric forms, e.g., 1-phenylethyl and 2- phenylethyl), and phenylpropyl (including all isomeric forms, e.g., 1-phenylpropyl, 2- phenylpropyl, and 3-phenylpropyl). In certain embodiments, the aralkyl is optionally substituted with one or more substituents Q as described herein.

[0031] The term “aralkylene” or “arylalkylene” refers to a divalent alkyl group substituted with one or more aryl groups. In certain embodiments, the aralkylene has from 7 to 30 (C7-30), from 7 to 20 (C7-20), or from 7 to 16 (C7-16) carbon atoms. Examples of aralkylene groups include, but are not limited to, benzylene (including all isomeric forms, e.g., phenylmethdiyl), phenylethylene (including all isomeric forms, e.g., 2-phenyl-ethan-1,1-diyl and 2-phenyl-ethan-1,2-diyl), and phenylpropylene (including all isomeric forms, e.g., 3-phenyl- propan-1,1-diyl, 3-phenyl-propan-1,2-diyl, and 3-phenyl-propan-1,3-diyl). In certainAttorney Docket No.215A001WO01 embodiments, the aralkylene is optionally substituted with one or more substituents Q as described herein.

[0032] The term “heteroaryl” refers to a monovalent monocyclic aromatic group or monovalent polycyclic aromatic group that contain at least one aromatic ring, wherein at least one aromatic ring contains one or more heteroatoms, each independently selected from O, S, and N, in the ring. For a heteroaryl group containing a heteroaromatic ring and a nonaromatic heterocyclic ring, the heteroaryl group is not bonded to the rest of a molecule through its nonaromatic heterocyclic ring. Each ring of a heteroaryl group can contain one or two O atoms, one or two S atoms, and / or one to four N atoms; provided that the total number of heteroatoms in each ring is four or less and each ring contains at least one carbon atom. In certain embodiments, the heteroaryl has from 5 to 20, from 5 to 15, or from 5 to 10 ring atoms. In one embodiment, the heteroaryl is monocyclic. Examples of monocyclic heteroaryl groups include, but are not limited to, furanyl, imidazolyl, isothiazolyl, isoxazolyl, oxadiazolyl, oxazolyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, thiadiazolyl, thiazolyl, thienyl, tetrazolyl, triazinyl, and triazolyl. In another embodiment, the heteroaryl is bicyclic. Examples of bicyclic heteroaryl groups include, but are not limited to, benzofuranyl, benzimidazolyl, benzoisoxazolyl, benzopyranyl, benzothiadiazolyl, benzothiazolyl, benzothienyl, benzotriazolyl, benzoxazolyl, furopyrindyl (including all isomeric forms, e.g., furo[2,3-b]pyridinyl, furo[2,3-c]pyridinyl, furo[3,2-b]pyridinyl, furo[3,2-c]pyridinyl, furo[3,4-b]pyridinyl, and furo[3,4-c]pyridinyl), imidazopyridinyl (including all isomeric forms, e.g., imidazo[1,2-a]pyridinyl, imidazo[4,5- b]pyridinyl, and imidazo[4,5-c]pyridinyl), imidazothiazolyl (including all isomeric forms, e.g., imidazo[2,1-b]thiazolyl and imidazo[4,5-d]thiazolyl), indazolyl, indolizinyl, indolyl, isobenzofuranyl, isobenzothienyl (i.e., benzo[c]thienyl), isoindolyl, isoquinolinyl, naphthyridinyl (including all isomeric forms, e.g., 1,5-naphthyridinyl, 1,6-naphthyridinyl, 1,7-naphthyridinyl, and 1,8-naphthyridinyl), oxazolopyridinyl (including all isomeric forms, e.g., oxazolo[4,5- b]pyridinyl, oxazolo[4,5-c]pyridinyl, oxazolo[5,4-b]pyridinyl, and oxazolo[5,4-c]pyridinyl), phthalazinyl, pteridinyl, purinyl, pyrrolopyridyl (including all isomeric forms, e.g., pyrrolo[2,3- b]pyridinyl, pyrrolo[2,3-c]pyridinyl, pyrrolo[3,2-b]pyridinyl, and pyrrolo[3,2-c]pyridinyl), quinolinyl, quinoxalinyl, quinazolinyl, thiadiazolopyrimidyl (including all isomeric forms, e.g., [1,2,5]thiadiazolo[3,4-d]pyrimidinyl and [1,2,3]thiadiazolo[4,5-d]pyrimidinyl), and thieno- pyridyl (including all isomeric forms, e.g., thieno[2,3-b]pyridinyl, thieno[2,3-c]pyridinyl,Attorney Docket No.215A001WO01 thieno[3,2-b]pyridinyl, and thieno[3,2-c]pyridinyl). In yet another embodiment, the heteroaryl is tricyclic. Examples of tricyclic heteroaryl groups include, but are not limited to, acridinyl, benz- indolyl, carbazolyl, dibenzofuranyl, perimidinyl, phenanthrolinyl, phenanthridinyl (including all isomeric forms, e.g., 1,5-phenanthrolinyl, 1,6-phenanthrolinyl, 1,7-phenanthrolinyl, 1,9-phen- anthrolinyl, and 2,10-phenanthrolinyl), phenarsazinyl, phenazinyl, phenothiazinyl, phenoxazinyl, and xanthenyl. In certain embodiments, the heteroaryl is optionally substituted with one or more substituents Q as described herein.

[0033] The terms “heteroarylene” and “heteroarenediyl” are used interchangeably herein in reference to a divalent monocyclic aromatic group or divalent polycyclic aromatic group that contains at least one aromatic ring, wherein at least one aromatic ring contains one or more heteroatoms in the ring, each of which is independently selected from O, S, and N. For a heteroarylene group containing a heteroaromatic ring and a nonaromatic heterocyclic ring, the heteroarylene group is not bonded to the rest of a molecule via its nonaromatic heterocyclic ring. Each ring of a heteroarylene group can contain one or two O atoms, one or two S atoms, and / or one to four N atoms, provided that the total number of heteroatoms in each ring is four or less and each ring contains at least one carbon atom. In certain embodiments, the heteroarylene has from 5 to 20, from 5 to 15, or from 5 to 10 ring atoms. Examples of monocyclic heteroarylene groups include, but are not limited to, furandiyl, imidazoldiyl, isothiazoldiyl, isoxazoldiyl, oxadiazoldiyl, oxazoldiyl, pyrazindiyl, pyrazoldiyl, pyridazindiyl, pyridindiyl, pyrimidindiyl, pyrroldiyl, thiadiazoldiyl, thiazoldiyl, thiendiyl, tetrazoldiyl, triazinediyl, and triazoldiyl. Examples of bicyclic heteroarylene groups include, but are not limited to, benzofurandiyl, benzimidazoldiyl, benzoisoxazoldiyl, benzopyrandiyl, benzothiadiazoldiyl, benzothiazoldiyl, benzothiendiyl, benzotriazoldiyl, benzoxazoldiyl, furopyridindiyl (including all isomeric forms, e.g., furo[2,3-b]pyridindiyl, furo[2,3-c]pyridindiyl, furo[3,2-b]pyridindiyl, furo[3,2-c]- pyridindiyl, furo[3,4-b]pyridindiyl, and furo[3,4-c]pyridindiyl), imidazopyridindiyl (including all isomeric forms, e.g., imidazo[1,2-a]pyridindiyl, imidazo[4,5-b]pyridindiyl, and imidazo[4,5-c]- pyridindiyl), imidazothiazoldiyl (including all isomeric forms, e.g., imidazo[2,1-b]thiazoldiyl and imidazo[4,5-d]thiazoldiyl), indazoldiyl, indolizindiyl, indoldiyl, isobenzofurandiyl, isobenzothiendiyl (i.e., benzo[c]thiendiyl), isoindoldiyl, isoquinolindiyl, naphthyridindiyl (including all isomeric forms, e.g., 1,5-naphthyridindiyl, 1,6-naphthyridindiyl, 1,7- naphthyridindiyl, and 1,8-naphthyridindiyl), oxazolopyridindiyl (including all isomeric forms,Attorney Docket No.215A001WO01 e.g., oxazolo[4,5-b]pyridindiyl, oxazolo[4,5-c]pyridindiyl, oxazolo[5,4-b]pyridindiyl, and oxazolo[5,4-c]pyridindiyl), phthalazindiyl, pteridindiyl, purindiyl, pyrrolopyridindiyl (including all isomeric forms, e.g., pyrrolo[2,3-b]pyridindiyl, pyrrolo[2,3-c]pyridindiyl, pyrrolo[3,2-b]- pyridindiyl, and pyrrolo[3,2-c]pyridindiyl), quinolindiyl, quinoxalindiyl, quinazolindiyl, thiadiazolopyrimidindiyl (including all isomeric forms, e.g., [1,2,5]thiadiazolo[3,4-d]- pyrimidindiyl and [1,2,3]thiadiazolo[4,5-d]pyrimidindiyl), and thienopyridindiyl (including all isomeric forms, e.g., thieno[2,3-b]pyridindiyl, thieno[2,3-c]pyridindiyl, thieno[3,2-b]pyridindiyl, and thieno[3,2-c]pyridindiyl). Examples of tricyclic heteroarylene groups include, but are not limited to, acridindiyl, benzindoldiyl, carbazoldiyl, dibenzofurandiyl, perimidindiyl, phenanthrolindiyl (including all isomeric forms, e.g., 1,5-phenanthrolindiyl, 1,6- phenanthrolindiyl, 1,7-phenanthrolindiyl, 1,9-phenanthrolindiyl, and 2,10-phenanthrolindiyl), phenanthridindiyl, phenarsazindiyl, phenazindiyl, phenothiazindiyl, phenoxazindiyl, and xanthendiyl. In certain embodiments, heteroarylene is optionally substituted with one or more substituents Q as described herein.

[0034] The term “heterocyclyl” or “heterocyclic” refers to a monovalent monocyclic non-aromatic ring system or monovalent polycyclic ring system that contains at least one non- aromatic ring, wherein one or more of the non-aromatic ring atoms are heteroatoms, each independently selected from O, S, and N; and the remaining ring atoms are carbon atoms. For a heterocyclyl group containing a heteroaromatic ring and a nonaromatic heterocyclic ring, the heterocyclyl group is not bonded to the rest of a molecule through the heteroaromatic ring. In certain embodiments, the heterocyclyl or heterocyclic group has from 3 to 20, from 3 to 15, from 3 to 10, from 3 to 8, from 4 to 7, or from 5 to 6 ring atoms. In certain embodiments, the heterocyclyl is a monocyclic, bicyclic, tricyclic, or tetracyclic ring system, which may be fused or bridged, and in which nitrogen or sulfur atoms may be optionally oxidized, nitrogen atoms may be optionally quaternized, and some rings may be partially or fully saturated, or aromatic. The heterocyclyl may be attached to the main structure at any heteroatom or carbon atom which results in the creation of a stable compound. Examples of heterocyclyls and heterocyclic groups include, but are not limited to, azepinyl, benzodioxanyl, benzodioxolyl, benzofuranonyl, chromanyl, decahydroisoquinolinyl, dihydrobenzofuranyl, dihydrobenzisothiazolyl, dihydro- benzisoxazinyl (including all isomeric forms, e.g., 1,4-dihydrobenzo[d][1,3]oxazinyl, 3,4- dihydrobenzo[c][1,2]-oxazinyl, and 3,4-dihydrobenzo[d][1,2]oxazinyl), dihydrobenzothienyl,Attorney Docket No.215A001WO01 dihydroisobenzofuranyl, dihydrobenzo[c]thienyl, dihydrofuryl, dihydroisoindolyl, dihydro- pyranyl, dihydropyrazolyl, dihydropyrazinyl, dihydropyridinyl, dihydropyrimidinyl, dihydro- pyrrolyl, dioxolanyl, 1,4-dithianyl, furanonyl, imidazolidinyl, imidazolinyl, indolinyl, isochromanyl, isoindolinyl, isothiazolidinyl, isoxazolidinyl, morpholinyl, octahydroindolyl, octahydroisoindolyl, oxazolidinonyl, oxazolidinyl, oxiranyl, piperazinyl, piperidinyl, 4- piperidonyl, pyrazolidinyl, pyrazolinyl, pyrrolidinyl, pyrrolinyl, quinuclidinyl, tetrahydrofuryl, tetrahydroisoquinolinyl, tetrahydropyranyl, tetrahydrothienyl, thiamorpholinyl, thiazolidinyl, thiochromanyl, tetrahydroquinolinyl, and 1,3,5-trithianyl. In certain embodiments, the heterocyclyl is optionally substituted with one or more substituents Q as described herein.

[0035] The term “heterocyclylene” refers to a divalent monocyclic non-aromatic ring system or divalent polycyclic ring system that contains at least one non-aromatic ring, wherein one or more of the non-aromatic ring atoms are heteroatoms independently selected from O, S, and N; and the remaining ring atoms are carbon atoms. For a heterocyclylene group containing a heteroaromatic ring and a nonaromatic heterocyclic ring, the heterocyclylene group has at least one bond to the rest of a molecule via its nonaromatic heterocyclic ring. In certain embodiments, the heterocyclylene group has from 3 to 20, from 3 to 15, from 3 to 10, from 3 to 8, from 4 to 7, or from 5 to 6 ring atoms. In certain embodiments, the heterocyclylene is a monocyclic, bicyclic, tricyclic, or tetracyclic ring system, which may be fused or bridged, and in which nitrogen or sulfur atoms may be optionally oxidized, nitrogen atoms may be optionally quaternized, and some rings may be partially or fully saturated, or aromatic. The heterocyclylene may be attached to the main structure at any heteroatom or carbon atom which results in the creation of a stable compound. Examples of such heterocyclylene groups include, but are not limited to, azepindiyl, benzodioxandiyl, benzodioxoldiyl, benzofuranondiyl, chromandiyl, decahydroisoquinolindiyl, dihydrobenzofurandiyl, dihydrobenzisothiazoldiyl, dihydrobenzisoxazindiyl (including all isomeric forms, e.g., 1,4-dihydrobenzo[d][1,3]oxazindiyl, 3,4-dihydrobenzo[c][1,2]oxazindiyl, and 3,4-dihydrobenzo[d][1,2]oxazindiyl), dihydrobenzothiendiyl, dihydroisobenzofurandiyl, dihydrobenzo[c]thiendiyl, dihydrofurdiyl, dihydroisoindoldiyl, dihydropyrandiyl, dihydro- pyrazoldiyl, dihydropyrazindiyl, dihydropyridindiyl, dihydropyrimidindiyl, dihydropyrroldiyl, dioxolandiyl, 1,4-dithiandiyl, furanondiyl, imidazolidindiyl, imidazolindiyl, indolindiyl, isochromandiyl, isoindolindiyl, isothiazolidindiyl, isoxazolidindiyl, morpholindiyl, octahydro- indoldiyl, octahydroisoindoldiyl, oxazolidinondiyl, oxazolidindiyl, oxirandiyl, piperazindiyl,Attorney Docket No.215A001WO01 piperidindiyl, 4-piperidondiyl, pyrazolidindiyl, pyrazolindiyl, pyrrolidindiyl, pyrrolindiyl, quinuclidindiyl, tetrahydrofurdiyl, tetrahydroisoquinolindiyl, tetrahydropyrandiyl, tetrahydro- thiendiyl, thiamorpholindiyl, thiazolidindiyl, thiochromandiyl, tetrahydroquinolindiyl, and 1,3,5- trithiandiyl. In certain embodiments, the heterocyclylene is optionally substituted with one or more substituents Q as described herein.

[0036] The term “halogen,” “halide,” or “halo” refers to fluoro, chloro, bromo, and / or iodo.

[0037] The term “optionally substituted” is intended to mean that a group or substituent, such as an alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, or heterocyclylene group, may be substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, each of which is independently selected from, e.g., (a) deuterium (–D), cyano (–CN), halo, nitro (–NO2), and oxo (=O); (b) C1-6alkyl, C1-6heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa. As used herein, all groups that can be substituted are “optionally substituted.”Attorney Docket No.215A001WO01

[0038] In one embodiment, each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)Rh, –NReS(O)2F, –NReS(O)2Rh, –NReS(O)2ORh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2F, –S(O)2Re, –S(O)2ORe, –S(O)NRfRg, and –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

[0039] For a divalent group described herein, no orientation is implied by the direction in which the divalent group is presented. For example, unless a particular orientation is specified, the formula –C(O)NH– represents both –C(O)NH– and –NHC(O)–.

[0040] The term “a” or “an” means “one or more” unless the context clearly indicates otherwise. Crosslinked Perfluorinated Polymers

[0041] In one embodiment, provided herein is a crosslinked perfluorinated polymer or a salt thereof, wherein the crosslinked perfluorinated polymer comprises two or more polymeric chains, each polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of Formula (I): wherein:the two or more polymeric chains are crosslinked via one or more divalent crosslinkers,Attorney Docket No.215A001WO01 each divalent crosslinker having the structure , wherein one A is attached to a repeating unit of a polymeric A isattached to a repeating unit of a different as that the two X are paired together to form a divalent crosslinker; and free X groups, i.e., the X groups that are not a part of crosslinking, are each independently halo, –OR1a, or –NR1bR1c; each A is independently –O– or ––N(R1b)–; each L is independently a bond, C1-15alkylene, C1-15heteroalkylene, C2-10alkenylene, C2-10alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene; each R1, R2, R3, and R4is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-6 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; and each r is independently an integer ranging from about 1 to about 100, in one embodiment, from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc,Attorney Docket No.215A001WO01 –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)2F, –NReS(O)Rh, –NReS(O)2ORh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2F, –S(O)2Re, –S(O)2ORe, –S(O)NRfRg, and –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

[0042] In another embodiment, provided herein is a crosslinked perfluorinated polymer or a salt thereof, wherein the crosslinked perfluorinated polymer comprises two or more polymeric chains, each polymeric chain comprising the structure of Formula (II): wherein:the two or more polymeric chains are crosslinked via one or more divalent crosslinkers,Attorney Docket No.215A001WO01 each divalent crosslinker having the structure , wherein one A is attached to a repeating unit of a polymeric A isattached to a repeating unit of a different as that the two X are paired together to form a divalent crosslinker; and free X groups are each independently halo, –OR1a, or –NR1bR1c; each z is independently an integer ranging from about 10 to about 2,000; and each R1, R2, R3, R4, R1a, R1b, R1c, A, L m, p, q, and r is as defined herein.

[0043] In yet another embodiment, provided herein is a crosslinked perfluorinated polymer or a salt thereof, wherein the crosslinked perfluorinated polymer comprises two or more polymeric chains, each polymeric chain having the structure of Formula (III): wherein:the two or more polymeric chains are crosslinked via one or more divalent crosslinkers, each divalent crosslinker having the structure , wherein one A is attached to a repeating unit of a polymericA is attached to a repeating unit of a different polymeric chain at the X position as such that the two X are paired together to form a divalent crosslinker; and free X groups are each independently halo, –OR1a, or –NR1bR1c; n is an integer ranging from about 1 to about 50; and each R1, R2, R3, R4, R1a, R1b, R1c, A, L m, p, q, r, and z is as defined herein.

[0044] In certain embodiments, A is –O–. In certain embodiments, A is –N(R1b)–, wherein R1bis as defined herein. In certain embodiments, A is –N(H)–.

[0045] In certain embodiments, each L is independently (i) a bond; or (ii) C1-15 alkyleneAttorney Docket No.215A001WO01 or C1-15 heteroalkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each L is a bond. In certain embodiments, each L is independently C1-15 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or more substituents Q. In certain embodiments, each L is independently methane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5- diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C1-15 heteroalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C1-6alkylene–O–C1-6alkylene or C1-6alkylene–S–C1-6alkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each L is independently –CH2CH2OCH2CH2–, –CH2CH2OCH2CH2CH2– or –CH2CH2SCH2CH2–, each optionally substituted with one or more substituents Q. In certain embodiments, each L is independently a bond, ethane-1,2-diyl, propane-1,3-diyl, –CH2CH2OCH2CH2CH2–, or –CH2CH2SCH2CH2–.

[0046] In certain embodiments, each L is independently C2-10 alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C2-10alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C3-10 cycloalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C6-14arylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently C7-15 aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each L is independently heterocyclylene, optionally substituted with one or more substituents Q.

[0047] In certain embodiments, the moiety –A–L– is –O–, –OCH2CH2OCH2CH2–, –OCH2CH2OCH2CH2CH2–, –OCH2CH2SCH2CH2–, or –N(H)CH2CH2CH2–. In certain embodiments, the moiety –A–L– is –O–. In certain embodiments, the moiety –A–L– is –OCH2CH2OCH2CH2CH2–. In certain embodiments, the moiety –A–L– is –OCH2CH2SCH2CH2–. In certain embodiments, the moiety –A–L– is –N(H)CH2CH2CH2–.Attorney Docket No.215A001WO01

[0048] In certain embodiments, each free X group is independently halo. In certain embodiments, each free X group is independently fluoro or chloro. In certain embodiments, each free X group is fluoro. In certain embodiments, each free X group is independently –OR1a, wherein R1ais as defined herein. In certain embodiments, each free X group is –OH.

[0049] In certain embodiments, each free X group is independently –NR1bR1c, wherein R1band R1care each as defined herein. In certain embodiments, each free X group is independently –NR1bR1c, wherein R1band R1care each independently hydrogen or C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each free X group is independently –NR1bR1c, wherein R1band R1care each independently (i) hydrogen; or (ii) methyl, ethyl, or propyl, each optionally substituted with one or more substituents Q.

[0050] In certain embodiments, each divalent crosslinker independently has the structure , wherein each R1, R2, R3, R4, and r is as defined herein; in one R4is independently C1-6 alkyl or C1-6heteroalkyl, each optionally substituted with one or more substituents Q; in another embodiment, each R1, R2, R3, and R4is independently methyl or 3,3,3-trifluoropropyl; in yet another embodiment, each R1, R2, R3, and R4is methyl; in yet another embodiment, each R1, R2, and R3is methyl, and each R4is 3,3,3-trifluoropropyl; in still another embodiment, each R1and R3is methyl, and each R2and R4is 3,3,3-trifluoropropyl.

[0051] In certain embodiments, each divalent crosslinker independently has the structure of , wherein each A is independently –O– or –NH–; each L isheteroalkylene, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, and r is as defined herein; in one embodiment, each A is independently –O– or –NH–, each L is independently propane-1,3-diyl, –CH2CH2O- CH2CH2–, –CH2CH2OCH2CH2CH2–, or –CH2CH2S-CH2CH2–, and each R1, R2, R3, and R4is independently methyl or 3,3,3-trifluoropropyl; in yet another embodiment, each A is independently –O– or –NH–, each L is independently propane-1,3-diyl, –CH2CH2OCH2CH2–,Attorney Docket No.215A001WO01 –CH2CH2OCH2CH2CH2–, or –CH2CH2S-CH2CH2–, and each R1, R2, R3, and R4is methyl; in yet another embodiment, each A is independently –O– or –NH–, each L is propane-1,3-diyl, –CH2CH2OCH2CH2–, –CH2CH2OCH2CH2CH2–, or –CH2CH2S-CH2CH2–, each R1, R2, and R3is methyl, and each R4is 3,3,3-trifluoropropyl; in still another embodiment, each A is independently –O– or –NH–, each L is independently propane-1,3-diyl, –CH2CH2OCH2CH2–, –CH2CH2OCH2CH2CH2–, or –CH2CH2S-CH2CH2–, each R1and R3is methyl, and each R2and R4is 3,3,3-trifluoropropyl.

[0052] In certain embodiments, each R1is independently C1-6 alkyl or is C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently methyl, ethyl, propyl, or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R1is methyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C1-6 heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently trifluoromethyl, 2,2,2-trifluoroethyl, or 3,3,3-trifluoro- propyl. In certain embodiments, each R1is independently methyl or 3,3,3-trifluoropropyl.

[0053] In certain embodiments, each R1is independently C2-6alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C2-6alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C3-10cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R1is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0054] In certain embodiments, each R2is independently C1-6alkyl or is C1-6heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently methyl, ethyl, propyl, or butyl, each optionallyAttorney Docket No.215A001WO01 substituted with one or more substituents Q. In certain embodiments, each R2is methyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C1-6heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently trifluoromethyl, 2,2,2-trifluoroethyl, or 3,3,3-trifluoro- propyl. In certain embodiments, each R2is independently methyl or 3,3,3-trifluoropropyl.

[0055] In certain embodiments, each R2is independently C2-6alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C2-6 alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C3-10cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C6-14aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently C7-15 aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R2is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0056] In certain embodiments, each R1and R2is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R1and R2is independently methyl or 3,3,3-trifluoropropyl. In certain embodiments, each R1and R2is methyl. In certain embodiments, each R1is methyl and each R2is 3,3,3-trifluoropropyl.

[0057] In certain embodiments, each R3is independently C1-6alkyl or is C1-6heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently methyl, ethyl, propyl, or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R3is methyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently C1-6heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently trifluoromethyl, 2,2,2-trifluoroethyl, or 3,3,3-trifluoro- propyl. In certain embodiments, each R3is independently methyl or 3,3,3-trifluoropropyl.

[0058] In certain embodiments, each R3is independently C2-6alkenyl, optionallyAttorney Docket No.215A001WO01 substituted with one or more substituents Q. In certain embodiments, each R3is independently C2-6 alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently C3-10cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently C7-15 aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R3is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0059] In certain embodiments, each R4is independently C1-6alkyl or is C1-6heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently methyl, ethyl, propyl, or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R4is methyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C1-6 heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently trifluoromethyl, 2,2,2-trifluoroethyl, or 3,3,3-trifluoro- propyl. In certain embodiments, each R4is independently methyl or 3,3,3-trifluoropropyl.

[0060] In certain embodiments, each R4is independently C2-6 alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C2-6alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C3-10 cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C6-14aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R4is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0061] In certain embodiments, each R3and R4is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R3and R4is independently methyl or 3,3,3-trifluoropropyl. In certainAttorney Docket No.215A001WO01 embodiments, each R3and R4is methyl. In certain embodiments, each R3is methyl and each R4is 3,3,3-trifluoropropyl.

[0062] In certain embodiments, each m is independently an integer ranging from about 1 to about 40, from about 1 to about 30, from about 1 to about 20, from about 1 to about 15, or from about 1 to about 10. In certain embodiments, each m is independently an integer ranging from about 1 to about 40. In certain embodiments, each m is independently an integer ranging from about 1 to about 30. In certain embodiments, each m is independently an integer ranging from about 1 to about 20. In certain embodiments, each m is independently an integer ranging from about 1 to about 15. In certain embodiments, each m is independently an integer ranging from about 1 to about 10. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In certain embodiments, each m is independently an integer of 4, 5, 6, 7, or 8.

[0063] In certain embodiments, each n is independently an integer ranging from about 1 to about 40, from about 1 to about 30, from about 1 to about 20, from about 1 to about 15, or from about 1 to about 10. In certain embodiments, each n is independently an integer ranging from about 1 to about 40. In certain embodiments, each n is independently an integer ranging from about 1 to about 30. In certain embodiments, each n is independently an integer ranging from about 1 to about 20. In certain embodiments, each n is independently an integer ranging from about 1 to about 15. In certain embodiments, each n is independently an integer ranging from about 1 to about 10. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In certain embodiments, each n is independently an integer of 4, 5, 6, 7, or 8

[0064] In certain embodiments, each p is independently an integer of 0, 1, 2, or 3. In certain embodiments, each p is an integer of 0. In certain embodiments, each p is 1. In certain embodiments, each p is 2. In certain embodiments, each p is 3. In certain embodiments, each pAttorney Docket No.215A001WO01 is 4. In certain embodiments, each p is 5.

[0065] In certain embodiments, each q is independently an integer of 1, 2, 3, 4, or 5. In certain embodiments, each q is an integer of 0. In certain embodiments, each q is 1. In certain embodiments, each q is 2. In certain embodiments, each q is 3. In certain embodiments, each q is 4. In certain embodiments, each q is 5. In certain embodiments, each q is an integer of 6. In certain embodiments, each q is 7. In certain embodiments, each q is 8. In certain embodiments, each q is 9. In certain embodiments, each q is 10.

[0066] In certain embodiments, each p is independently an integer of 0, 1, 2, or 3; and each q is independently an integer of 1, 2, 3, 4, or 5. In certain embodiments, each p is independently an integer of 0, 1, 2, or 3; and each q is independently an integer of 2, 3, 4, or 5. In certain embodiments, each p is independently an integer of 0 or 1; and each q is independently an integer of 1, 2, 3, 4, or 5. In certain embodiments, each p is an integer of 0; and each q is an integer of 2. In certain embodiments, each p is an integer of 0; and each q is an integer of 4. In certain embodiments, each p is an integer of 1; and each q is an integer of 2.

[0067] In certain embodiments, each r is independently an integer ranging from about 1 to about 100, from about 2 to about 75, from about 5 to about 60, from about 5 to about 50, from about 5 to about 40, from about 5 to about 30, or from about 5 to about 25. In certain embodiments, each r is independently an integer ranging from about 1 to about 100. In certain embodiments, each r is independently an integer ranging from about 2 to about 75. In certain embodiments, each r is independently an integer ranging from about 5 to about 60. In certain embodiments, each r is independently an integer ranging from about 5 to about 50. In certain embodiments, each r is independently an integer ranging from about 5 to about 40. In certain embodiments, each r is independently an integer ranging from about 5 to about 30. In certain embodiments, each r is independently an integer ranging from about 5 to about 25. In certain embodiments, each r is independently an integer of about 5, about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45, about 50, about 55, or about 60. In certain embodiments, each r is independently an integer of about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45, about 50, or about 55.

[0068] In certain embodiments, each z is independently an integer ranging from about 50Attorney Docket No.215A001WO01 to about 2,000, from about 100 to about 2,000, from about 100 to about 1,500, from about 100 to about 1,250, or from about 100 to about 1,000. In certain embodiments, each z is independently an integer ranging from about 50 to about 2,000. In certain embodiments, each z is independently an integer ranging from about 100 to about 2,000. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,500. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,250. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,000.

[0069] In certain embodiments, each divalent crosslinker independently has the structure H2CH2CH2C Si O Si O Si CH2CH2CH2, wherein r is as defined herein; in one to about 60; in another embodiment, r is anor In certain embodiments, each divalent crosslinker independently has the structure of , wherein each r is as defined herein; in oneabout 60; in another embodiment, r is an integer of about 9, about 10, about 22, or about 55.

[0070] In certain embodiments, the crosslinked perfluorinated polymer provided herein has an equivalent weight (EW) ranging from about 50 to about 2,000, from about 100 to about 1,500, from about 200 to about 1,250, or from about 500 to about 1,250. In certain embodiments, the crosslinked perfluorinated polymer provided herein has an EW ranging from about 50 to about 2,000. In certain embodiments, the crosslinked perfluorinated polymer provided herein has an EW ranging from about 100 to about 1,500. In certain embodiments, the crosslinked perfluorinated polymer provided herein has an EW ranging from about 200 to about 1,250. In certain embodiments, the crosslinked perfluorinated polymer provided herein has an EW ranging from about 500 to about 1,250.

[0071] In certain embodiments, the crosslinked perfluorinated polymer provided herein has a degree of crosslinking (DC) of no greater than about 50%, no greater than about 40%, noAttorney Docket No.215A001WO01 greater than about 30%, no greater than about 20%, or no greater than about 10%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC of no greater than about 50%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC of no greater than about 40%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC of no greater than about 30%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC of or no greater than about 20%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC of or no greater than about 10%.

[0072] In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC ranging from about 1 to about 50%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC ranging from about 2 to about 40%. In certain embodiments, the crosslinked perfluorinated polymer provided herein has a DC ranging from about 5 to about 25%. In certain embodiments, a DC of a crosslinked perfluorinated polymer provided herein is determined by an elemental analysis.

[0073] In certain embodiments, the crosslinked perfluorinated polymer provided herein is solid. In certain embodiments, the crosslinked perfluorinated polymer provided herein is in the form of powders. In certain embodiments, the crosslinked perfluorinated polymer provided herein is in the form of a polymer film.

[0074] In one embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof; comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of:Attorney Docket No.215A001WO01 with a compound having the structure in the presence of a base or a fluoride salt to form theeach E is independently –OSi 3 or each R5is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, R1b, L, Q, m, p, q, and r is as defined herein.

[0075] In another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof; comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising the structure of:with a compound having the structure in the presence of a base or a fluoride salt to form theeach R1, R2, R3, R4, E, L, m, p, q, r, and z is as defined herein.

[0076] In yet another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof; comprising the step of reacting a perfluorinated polymer having a polymeric chain having the structure of:with a compound having the structure in the presence of a baseAttorney Docket No.215A001WO01 or a fluoride salt to form the crosslinked perfluorinated polymer; wherein each R1, R2, R3, R4, E, L, m, n, p, q, r, and z is as defined herein.

[0077] In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is as defined herein. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or butyl. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or tert-butyl. In certain embodiments, each E is independently trimethylsilyloxy or tert-butyldimethylsilyloxy. In certain embodiments, each E is trimethylsilyloxy. In certain embodiments, each E is tert- butyldimethylsilyloxy. In certain embodiments, each E is independently –NHR1b, wherein R1bis as defined herein. In certain embodiments, each E is –NH2.

[0078] In certain embodiments, each R5is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl, ethyl, propyl, butyl, pentyl, or hexyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or tert-butyl. In certain embodiments, each R5is independently C1-6heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6 alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C3-10cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heterocyclyl, optionally substituted with one or more substituents Q.Attorney Docket No.215A001WO01

[0079] In certain embodiments, the crosslinking step is performed in the presence of a base. In certain embodiments, the base is an organic base. In certain embodiments, the base is a nonnucleophilic base. In certain embodiments, the base is 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), or 2-tert-butylimino-2-diethylamino-1,3- dimethylperhydro-1,3,2-diazaphosphorine (BEMP). In certain embodiments, the base is DBU. In certain embodiments, the base is TBD. In certain embodiments, the base is BEMP. In certain embodiments, the base is 4-dimethylaminopyridine (DMAP) or triethylamine (TEA). In certain embodiments, the base is DMAP. In certain embodiments, the base is TEA.

[0080] In certain embodiments, the crosslinking step is performed in the presence of a fluoride salt. In certain embodiments, the fluoride salt is a bifluoride salt. In certain embodiments, the fluoride salt is cesium fluoride, tris(dimethylamino)sulfonium bifluoride, hexamethyl guanidium bifluoride, or tetrabutylammonium bifluoride. In certain embodiments, the fluoride salt is cesium fluoride. In certain embodiments, the fluoride salt is tris(dimethylamino)sulfonium bifluoride. In certain embodiments, the fluoride salt is hexamethyl guanidium bifluoride. In certain embodiments, the fluoride salt is tetrabutylammonium bifluoride.

[0081] In certain embodiments, the crosslinking step is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the crosslinking step is performed at a temperature ranging from about 20 to about 400 ºC. In certain embodiments, the crosslinking step is performed at a temperature ranging from about 25 to about 300 ºC. In certain embodiments, the crosslinking step is performed at a temperature ranging from about 50 to about 200 ºC. In certain embodiments, the crosslinking step is performed at a temperature ranging from about 50 to about 100 ºC. In certain embodiments, the crosslinking step is performed at a temperature of about 50, about 60, about 70, about 80, about 90, or about 100 ºC.

[0082] In certain embodiments, the crosslinking step is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is acetonitrile (ACN), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methyl-2- pyrrolidone (NMP), tetrahydrofuran (THF), or a mixture thereof. In certain embodiments, theAttorney Docket No.215A001WO01 solvent is ACN. In certain embodiments, the solvent is DMF. In certain embodiments, the solvent is DMSO. In certain embodiments, the solvent is NMP. In certain embodiments, the solvent is THF.

[0083] In certain embodiments, the method provided herein further comprises the steps of converting the SO2F groups of the crosslinked perfluorinated polymer to sulfonate salt groups with a base (e.g., sodium hydroxide or potassium hydroxide) in a solvent (e.g., a mixture of DMSO and water); and converting the sulfonate salt groups to SO3H groups with an acid (e.g., nitric acid or sulfuric acid) in a solvent (e.g., a mixture of DMSO and water).

[0084] In certain embodiments, the crosslinking compound (i.e., a compound having the is defined herein; in oneembodiment, r is an integer of about 9, about 10, about 22, or about 55. In certain embodiments, the crosslinking in a method provided herein , wherein each r is as defined herein; in oneto about 60; in another embodiment, r is an integer ranging of about 9, about 10, about 22, or about 55.

[0085] In one embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingof a base or a fluoride salt toAttorney Docket No.215A001WO01 form a functionalized polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: wherein at least one Xaremaining Xagroups areeach fluoro; and (b) reacting the functionalized polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedwherein: each Laand Lbis independently C1-6alkylene, C1-6heteroalkylene, C2-6alkenylene, C2-6alkynylene, C3-10 cycloalkylene, C6-14 arylene, C7-15 aralkylene, heteroarylene, or heterocyclylene, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, A, E, Q, m, p, q, and r is as defined herein.

[0086] In another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising the structure of: with a compound havingof a base or a fluoride salt to form a functionalized polymer having a polymeric chain comprising the structure of: ;Attorney Docket No.215A001WO01 wherein at least one Xagroup has the structure of –A–La–SH; and the remaining Xagroups are each fluoro; and (b) reacting the functionalized polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedwherein each R1, R2, R3, R4, A, E, La, Lb, m, p, q, r, and z is as defined herein.

[0087] In yet another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having the structure of: with a compound havinga base or a fluoride salt to form a functionalized polymer having the structure of: ; wherein at least one XaremainingaX groups are each fluoro; and (b) reacting the functionalized polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedwherein each R1, R2, R3, R4, A, E, La, Lb, m, n, p, q, r, and z is as defined herein.

[0088] In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is as defined herein. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5isAttorney Docket No.215A001WO01 independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or butyl. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or tert-butyl. In certain embodiments, each E is independently trimethylsilyloxy or tert-butyldimethylsilyloxy. In certain embodiments, each E is trimethylsilyloxy. In certain embodiments, each E is tert- butyldimethylsilyloxy. In certain embodiments, each E is independently –NHR1b, wherein R1bis as defined herein. In certain embodiments, each E is –NH2.

[0089] In certain embodiments, each R5is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl, ethyl, propyl, butyl, pentyl, or hexyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or tert-butyl. In certain embodiments, each R5is independently C1-6 heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6 alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C3-10cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0090] In certain embodiments, each Lais independently C1-6alkylene or C1-6heteroalkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C1-6 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or moreAttorney Docket No.215A001WO01 substituents Q. In certain embodiments, each Lais independently methane-1,1-diyl, ethane-1,2- diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently ethane-1,2-diyl or propane-1,3-diyl. In certain embodiments, each Lais independently C1-6 heteroalkylene, optionally substituted with one or more substituents Q.

[0091] In certain embodiments, each Lais independently C2-6alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C2-6 alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C3-10cycloalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C6-14arylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C7-15 aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently heterocyclylene, optionally substituted with one or more substituents Q.

[0092] In certain embodiments, each Lbis independently C1-6alkylene or C1-6heteroalkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C1-6 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently methane-1,1-diyl, ethane-1,2- diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently methane-1,1-diyl or ethane-1,2-diyl. In certain embodiments, each Lbis independently C1-6 heteroalkylene, optionally substituted with one or more substituents Q.

[0093] In certain embodiments, each Lbis independently C2-6alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C2-6 alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C3-10cycloalkylene, optionally substituted with one or moreAttorney Docket No.215A001WO01 substituents Q. In certain embodiments, each Lbis independently C6-14 arylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C7-15aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently heterocyclylene, optionally substituted with one or more substituents Q.

[0094] In certain embodiments, the crosslinking step is performed in the presence of a base. In certain embodiments, the base is an organic base. In certain embodiments, the base is a nonnucleophilic base. In certain embodiments, the base is DBU, TBD, or BEMP. In certain embodiments, the base is DBU. In certain embodiments, the base is TBD. In certain embodiments, the base is BEMP. In certain embodiments, the base is DMAP or TEA. In certain embodiments, the base is DMAP. In certain embodiments, the base is TEA.

[0095] In certain embodiments, step (a) is performed in the presence of a fluoride salt. In certain embodiments, the fluoride salt is a bifluoride salt. In certain embodiments, the fluoride salt is cesium fluoride, tris(dimethylamino)sulfonium bifluoride, hexamethyl guanidium bifluoride, or tetrabutylammonium bifluoride. In certain embodiments, the fluoride salt is cesium fluoride. In certain embodiments, the fluoride salt is tris(dimethylamino)sulfonium bifluoride. In certain embodiments, the fluoride salt is hexamethyl guanidium bifluoride. In certain embodiments, the fluoride salt is tetrabutylammonium bifluoride.

[0096] In certain embodiments, step (a) is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 400 ºC. In certain embodiments, the temperature is ranging from about 25 to about 300 ºC. In certain embodiments, the temperature is ranging from about 50 to about 200 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC. In certain embodiments, the temperature is about 50, about 60, about 70, about 80, about 90, or about 100 ºC.

[0097] In certain embodiments, step (a) is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is ACN,Attorney Docket No.215A001WO01 DMF, DMSO, NMP, THF, or a mixture thereof. In certain embodiments, the solvent is ACN. In certain embodiments, the solvent is DMF. In certain embodiments, the solvent is DMSO. In certain embodiments, the solvent is NMP. In certain embodiments, the solvent is THF.

[0098] In certain embodiments, the radical initiator in step (b) is azobisisobutyronitrile (AIBN) or 1,1’-azobis(cyclohexanecarbonitrile) (ABCN). In certain embodiments, the radical initiator in step (b) is a photoinitiator. In certain embodiments, the photoinitiator in step (b) is 2,2-dimethoxy-2-phenylacetonephenone (DMPA).

[0099] In certain embodiments, step (b) is performed under UV light. In certain embodiments, step (b) is performed under UV light at 365 nM.

[0100] In certain embodiments, step (b) is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 400 ºC. In certain embodiments, the temperature is ranging from about 25 to about 300 ºC. In certain embodiments, the temperature is ranging from about 50 to about 200 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC.

[0101] In certain embodiments, step (b) is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, or a mixture thereof. In certain embodiments, the solvent is ACN. In certain embodiments, the solvent is DMF. In certain embodiments, the solvent is DMSO. In certain embodiments, the solvent is NMP. In certain embodiments, the solvent is THF.

[0102] In certain embodiments, the method provided herein further comprises the steps of converting the SO2F groups of the crosslinked perfluorinated polymer to sulfonate salt groups with a base (e.g., sodium hydroxide or potassium hydroxide) in a solvent (e.g., a mixture of DMSO and water); and converting the sulfonate salt groups to SO3H groups with an acid (e.g., nitric acid or sulfuric acid) in a solvent (e.g., a mixture of DMSO and water).

[0103] In one embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two orAttorney Docket No.215A001WO01 more repeating units, each repeating unit having the structure of: with a compound having of a base or a fluoride salt toform a functionalized two or more repeating units, each repeating unit having the structure of: wherein at least one Xaremaining Xagroups areeach fluoro; (b) converting the SO2F groups of the functionalized polymer to sulfonate salt groups with a base; (c) converting the sulfonate salt groups of the functionalized polymer to SO3H groups with an acid; and (d) reacting the functionalized perfluorinated polymer with a compound having the structure in the presence of a radical initiator to form thewherein each R1, R2, R3, R4, A, E, La, Lb, m, p, q, and r is as defined herein.

[0104] In another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising the structure of: with a compound havingof a base or a fluoride salt toAttorney Docket No.215A001WO01 form a functionalized polymer having a polymeric chain comprising the structure of: CF2CF2m CF2CF z a ; wherein at least one Xaremaining Xagroups areeach fluoro; (b) converting the SO2F groups of the functionalized polymer to sulfonate salt groups with a base; (c) converting the sulfonate salt groups of the functionalized polymer to SO3H groups with an acid; and (d) reacting the functionalized perfluorinated polymer with a compound having the structure in the presence of a radical initiator to form thewherein each R1, R2, R3, R4, A, E, La, Lb, m, p, q, r, and z is as defined herein.

[0105] In yet another embodiment, provided herein is a method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having the structure of: with a compound havinga base or a fluoride salt to form a functionalized polymer having the structure of: wherein at least one Xaand the remaining Xagroups are each fluoro;Attorney Docket No.215A001WO01 (b) converting the SO2F groups of the functionalized polymer to sulfonate salt groups with a base; (c) converting the sulfonate salt groups of the functionalized polymer to SO3H groups with an acid; and (d) reacting the functionalized perfluorinated polymer with a compound having the structure in the presence of a radical initiator to form thewherein each R1, R2, R3, R4, A, E, La, Lb, m, n, p, q, r, and z is as defined herein.

[0106] In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is as defined herein. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6alkyl or C1-6heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or butyl. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or tert-butyl. In certain embodiments, each E is independently trimethylsilyloxy or tert-butyldimethylsilyloxy. In certain embodiments, each E is trimethylsilyloxy. In certain embodiments, each E is tert- butyldimethylsilyloxy. In certain embodiments, each E is independently –NHR1b, wherein R1bis as defined herein. In certain embodiments, each E is –NH2.

[0107] In certain embodiments, each R5is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl, ethyl, propyl, butyl, pentyl, or hexyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or tert-butyl. In certain embodiments, each R5is independently C1-6 heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6 alkynyl, optionally substituted with one orAttorney Docket No.215A001WO01 more substituents Q. In certain embodiments, each R5is independently C3-10 cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C6-14aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C7-15 aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0108] In certain embodiments, each Lais independently C1-6 alkylene or C1-6 heteroalkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C1-6alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently methane-1,1-diyl, ethane-1,2- diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently ethane-1,2-diyl or propane-1,3-diyl. In certain embodiments, each Lais independently C1-6heteroalkylene, optionally substituted with one or more substituents Q.

[0109] In certain embodiments, each Lais independently C2-6 alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C2-6alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C3-10 cycloalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C6-14arylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently C7-15aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lais independently heterocyclylene, optionally substituted with one or more substituents Q.

[0110] In certain embodiments, each Lbis independently C1-6 alkylene or C1-6 heteroalkylene, each optionally substituted with one or more substituents Q. In certainAttorney Docket No.215A001WO01 embodiments, each Lbis independently C1-6 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently methane-1,1-diyl, ethane-1,2- diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently ethane-1,2-diyl or propane-1,3-diyl. In certain embodiments, each Lbis independently C1-6heteroalkylene, optionally substituted with one or more substituents Q.

[0111] In certain embodiments, each Lbis independently C2-6alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C2-6 alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C3-10 cycloalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C6-14arylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently C7-15 aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each Lbis independently heterocyclylene, optionally substituted with one or more substituents Q.

[0112] In certain embodiments, step (a) is performed in the presence of a base. In certain embodiments, the base is an organic base. In certain embodiments, the base is a non- nucleophilic base. In certain embodiments, the base is DBU, TBD, or BEMP. In certain embodiments, the base is DBU. In certain embodiments, the base is TBD. In certain embodiments, the base is BEMP. In certain embodiments, the base is DMAP or TEA. In certain embodiments, the base is DMAP. In certain embodiments, the base is TEA.

[0113] In certain embodiments, step (a) is performed in the presence of a fluoride salt. In certain embodiments, the fluoride salt is a bifluoride salt. In certain embodiments, the fluoride salt is cesium fluoride, tris(dimethylamino)sulfonium bifluoride, hexamethyl guanidium bifluoride, or tetrabutylammonium bifluoride. In certain embodiments, the fluoride salt is cesium fluoride. In certain embodiments, the fluoride salt is tris(dimethylamino)sulfoniumAttorney Docket No.215A001WO01 bifluoride. In certain embodiments, the fluoride salt is hexamethyl guanidium bifluoride. In certain embodiments, the fluoride salt is tetrabutylammonium bifluoride.

[0114] In certain embodiments, step (a) is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 400 ºC. In certain embodiments, the temperature is ranging from about 25 to about 300 ºC. In certain embodiments, the temperature is ranging from about 50 to about 200 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC. In certain embodiments, the temperature is about 50, about 60, about 70, about 80, about 90, or about 100 ºC.

[0115] In certain embodiments, step (a) is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, or a mixture thereof. In certain embodiments, the solvent is ACN. In certain embodiments, the solvent is DMF. In certain embodiments, the solvent is DMSO. In certain embodiments, the solvent is NMP. In certain embodiments, the solvent is THF.

[0116] In certain embodiments, the base in step (b) is an inorganic base. In certain embodiments, the base in step (b) is an alkali hydroxide. In certain embodiments, the base in step (b) is sodium hydroxide or potassium hydroxide. In certain embodiments, the base in step (b) is potassium hydroxide.

[0117] In certain embodiments, step (b) is performed at a temperature ranging from about 20 to about 100 ºC, from about 30 to about 100 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 100 ºC. In certain embodiments, the temperature is ranging from about 30 to about 100 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC.

[0118] In certain embodiments, step (b) is performed in a solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, water, or a mixture thereof. In certain embodiments, the solvent is a mixture of DMSO and water.

[0119] In certain embodiments, the acid in step (c) is an inorganic acid. In certainAttorney Docket No.215A001WO01 embodiments, the acid in step (c) is nitric acid or sulfuric acid. In certain embodiments, the acid in step (c) is nitric acid. In certain embodiments, the acid in step (c) is sulfuric acid.

[0120] In certain embodiments, step (c) is performed at a temperature ranging from about 20 to about 100 ºC, from about 30 to about 100 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 100 ºC. In certain embodiments, the temperature is ranging from about 30 to about 100 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC.

[0121] In certain embodiments, step (c) is performed in a solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, water, or a mixture thereof. In certain embodiments, the solvent is a mixture of DMSO and water.

[0122] In certain embodiments, the radical initiator in step (d) is AIBN or ABCN. In certain embodiments, the radical initiator in step (d) is a photoinitiator. In certain embodiments, the photoinitiator in step (d) is DMPA.

[0123] In certain embodiments, step (d) is performed under UV light. In certain embodiments, step (d) is performed under UV light at 365 nM.

[0124] In certain embodiments, step (d) is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the temperature is ranging from about 20 to about 400 ºC. In certain embodiments, the temperature is ranging from about 25 to about 300 ºC. In certain embodiments, the temperature is ranging from about 50 to about 200 ºC. In certain embodiments, the temperature is ranging from about 50 to about 100 ºC.

[0125] In certain embodiments, step (d) is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, water, or a mixture thereof. In certain embodiments, the solvent is a mixture of DMSO and water.

[0126] In certain embodiments, the starting perfluorinated polymer (i.e., the perfluorinated polymer before crosslinking) in a method provided herein is solid. In certainAttorney Docket No.215A001WO01 embodiments, the starting perfluorinated polymer in a method provided herein is in the form of powders. In certain embodiments, the starting perfluorinated polymer in a method provided herein is in the form of a polymer film.

[0127] In certain embodiments, a crosslinked perfluorinated polymer or a salt thereof prepared by a method provided herein has the structure of a crosslinked perfluorinated polymer or a salt thereof provided herein.

[0128] In certain embodiments, provided herein is a crosslinked perfluorinated polymer or a salt thereof prepared by a method provided herein.

[0129] In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has an EW ranging from about 50 to about 2,000, from about 100 to about 1,500, from about 200 to about 1,250, or from about 500 to about 1,250. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has an EW ranging from about 50 to about 2,000. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has an EW ranging from about 100 to about 1,500. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has an EW ranging from about 200 to about 1,250. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has an EW ranging from about 500 to about 1,250.

[0130] In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of no greater than about 50%, no greater than about 40%, no greater than about 30%, no greater than about 20%, or no greater than about 10%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of no greater than about 50%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of no greater than about 40%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of no greater than about 30%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of or no greater than about 20%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC of or no greater than about 10%.Attorney Docket No.215A001WO01

[0131] In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC ranging from about 1 to about 50%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC ranging from about 2 to about 40%. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein has a DC ranging from about 5 to about 25%.

[0132] In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein is solid. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein is in the form of powders. In certain embodiments, the crosslinked perfluorinated polymer prepared by a method provided herein is in the form of a polymer film.

[0133] In certain embodiments, provided herein is a perfluorinated proton exchange membrane comprising a crosslinked perfluorinated polymer or a salt thereof provided herein.

[0134] In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 1 to about 500 µm, from about 5 to about 300 µm, or from about 10 to about 200 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 1 to about 500 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 5 to about 300 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 10 to about 200 µm.

[0135] In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 25%, no greater than about 20%, no greater than about 15%, no greater than about 10%, or no greater than about 5%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 25%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 20%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has aAttorney Docket No.215A001WO01 swelling ratio in plane of no greater than about 15%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 10%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 5%.

[0136] In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 25%, no greater than about 20%, no greater than about 15%, no greater than about 10%, or no greater than about 5%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 25%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 20%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 15%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 10%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 5%. Pegylated Perfluorinated Polymers

[0137] In one embodiment, provided herein is a pegylated perfluorinated polymer or a salt thereof, wherein the pegylated perfluorinated polymer has a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of Formula (I): wherein:at least one X group has the structure of –A–L1–(CH2CH2O)s–Z; and the remaining X groups are each independently halo, –OR1a, or –NR1bR1c; A is –O– or –N(R1b)–; L1is a bond, C1-15alkylene, C1-15heteroalkylene, C2-10alkenylene, C2-10alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene; Z is hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-Attorney Docket No.215A001WO01 14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6alkynyl, C3-6cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; and each s is independently an integer of ranging from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe,Attorney Docket No.215A001WO01 –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)2F, –NReS(O)Rh, –NReS(O)2ORh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2F, –S(O)2Re, –S(O)2ORe, –S(O)NRfRg, and –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

[0138] In another embodiment, provided herein is a pegylated perfluorinated polymer or a salt thereof, wherein the pegylated perfluorinated polymer has a polymeric chain comprising the structure of Formula (II): wherein:at least one X group has the structure of –A–L1–(CH2CH2O)s–Z; and the remaining X groups are each independently halo, –OR1a, or –NR1bR1c; each R1a, R1b, R1c, A, L1, Z, m, p, q, s, and z is as defined herein.

[0139] In yet another embodiment, provided herein is a pegylated perfluorinated polymer or a salt thereof, wherein the pegylated perfluorinated polymer has a polymeric chain having the structure of Formula (III): wherein:at least one X group has the structure of –A–L1–(CH2CH2O)s–Z; and the remaining X groups are each independently halo, –OR1a, or –NR1bR1c; each R1a, R1b, R1c, A, L1, Z, m, n, p, q, s, and z is as defined herein.Attorney Docket No.215A001WO01

[0140] In certain embodiments, A is –O–. In certain embodiments, A is –N(R1b)–, wherein R1bis as defined herein. In certain embodiments, A is –N(H)–.

[0141] In certain embodiments, each L1is independently (i) a bond; or (ii) C1-15alkylene or C1-15 heteroalkylene, each optionally substituted with one or more substituents Q. In certain embodiments, each L1is a bond. In certain embodiments, each L1is independently C1-15 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently methanediyl, ethanediyl, propanediyl, butanediyl, pentanediyl, or hexanediyl, each optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently methane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently methane-1,1-diyl, ethane-1,2-diyl, or propane-1,3-diyl, each optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C1-15heteroalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C1-6 alkylene–S–C1-6 alkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently –CH2CH2–S–CH2CH2–, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently a bond, methane-1,1- diyl, ethane-1,2-diyl, or propane-1,3-diyl. In certain embodiments, each L1is independently a bond or methane-1,1-diyl.

[0142] In certain embodiments, each L1is independently C2-10alkenylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C2-10alkynylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C3-10cycloalkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C6-14 arylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently C7-15aralkylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently heteroarylene, optionally substituted with one or more substituents Q. In certain embodiments, each L1is independently heterocyclylene, optionally substituted with one or more substituents Q.Attorney Docket No.215A001WO01

[0143] In certain embodiments, each moiety –A–L1– is independently –O– or –N(R1b)–, wherein R1bis as defined herein. In certain embodiments, each moiety –A–L1– is –O–. In certain embodiments, each moiety –A–L1– is –N(H)–. In certain embodiments, each moiety –A–L1– is –O–. –N(H)–, or –N(H)CH2–.

[0144] In certain embodiments, the remaining X groups are each independently halo. In certain embodiments, the remaining X groups are each independently fluoro or chloro. In certain embodiments, the remaining X groups are each fluoro. In certain embodiments, the remaining X groups are each independently –OR1a, wherein R1ais as defined herein. In certain embodiments, the remaining X groups are each –OH.

[0145] In certain embodiments, each Z is independently (i) hydrogen; or (ii) C1-6alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each Z is hydrogen. In certain embodiments, each Z is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C1-6 alkyl, optionally substituted with –C(O)ORa, –C(O)NRbRc, –S(O)2ORa, or –S(O)2NRbRc; wherein each Ra, Rb, and Rcis as defined herein. In certain embodiments, each Z is independently methyl, ethyl, propyl, or butyl, each optionally substituted with –CO2H or –SO3OH. In certain embodiments, each Z is independently methyl, –CH2SO3H, or –CH2CH2CO2H. In certain embodiments, each Z is independently C1-6heteroalkyl, optionally substituted with one or more substituents Q.

[0146] In certain embodiments, each Z is independently C2-6 alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C2-6alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C3-10 cycloalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each Z is independently heterocyclyl, optionally substituted with one or more substituents Q.Attorney Docket No.215A001WO01

[0147] In certain embodiments, each m is independently an integer ranging from about 1 to about 40, from about 1 to about 30, from about 1 to about 20, from about 1 to about 15, or from about 1 to about 10. In certain embodiments, each m is independently an integer ranging from about 1 to about 40. In certain embodiments, each m is independently an integer ranging from about 1 to about 30. In certain embodiments, each m is independently an integer ranging from about 1 to about 20. In certain embodiments, each m is independently an integer ranging from about 1 to about 15. In certain embodiments, each m is independently an integer ranging from about 1 to about 10. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. In certain embodiments, each m is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In certain embodiments, each m is independently an integer of 4, 5, 6, 7, or 8.

[0148] In certain embodiments, each n is independently an integer ranging from about 1 to about 40, from about 1 to about 30, from about 1 to about 20, from about 1 to about 15, or from about 1 to about 10. In certain embodiments, each n is independently an integer ranging from about 1 to about 40. In certain embodiments, each n is independently an integer ranging from about 1 to about 30. In certain embodiments, each n is independently an integer ranging from about 1 to about 20. In certain embodiments, each n is independently an integer ranging from about 1 to about 15. In certain embodiments, each n is independently an integer ranging from about 1 to about 10. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. In certain embodiments, each n is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In certain embodiments, each n is independently an integer of 4, 5, 6, 7, or 8

[0149] In certain embodiments, each p is independently an integer of 0, 1, 2, or 3. In certain embodiments, each p is an integer of 0. In certain embodiments, each p is 1. In certain embodiments, each p is 2. In certain embodiments, each p is 3. In certain embodiments, each p is 4. In certain embodiments, each p is 5.

[0150] In certain embodiments, each q is independently an integer of 1, 2, 3, 4, or 5. InAttorney Docket No.215A001WO01 certain embodiments, each q is an integer of 0. In certain embodiments, each q is 1. In certain embodiments, each q is 2. In certain embodiments, each q is 3. In certain embodiments, each q is 4. In certain embodiments, each q is 5. In certain embodiments, each q is an integer of 6. In certain embodiments, each q is 7. In certain embodiments, each q is 8. In certain embodiments, each q is 9. In certain embodiments, each q is 10.

[0151] In certain embodiments, each p is independently an integer of 0, 1, 2, or 3; and each q is independently an integer of 1, 2, 3, 4, or 5. In certain embodiments, each p is independently an integer of 0, 1, 2, or 3; and each q is independently an integer of 2, 3, 4, or 5. In certain embodiments, each p is independently an integer of 0 or 1; and each q is independently an integer of 1, 2, 3, 4, or 5. In certain embodiments, each p is an integer of 0; and each q is an integer of 2. In certain embodiments, each p is an integer of 0; and each q is an integer of 4. In certain embodiments, each p is an integer of 1; and each q is an integer of 2.

[0152] In certain embodiments, each s is independently an integer ranging from about 1 to about 40, from about 1 to about 30, from about 1 to about 20, or from about 1 to about 10. In certain embodiments, each s is independently an integer ranging from about 1 to about 40. In certain embodiments, each s is independently an integer ranging from about 1 to about 30. In certain embodiments, each s is independently an integer ranging from about 1 to about 20. In certain embodiments, each s is independently an integer ranging from about 1 to about 10. In certain embodiments, each s is independently an integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0153] In certain embodiments, each z is independently an integer ranging from about 50 to about 2,000, from about 100 to about 2,000, from about 100 to about 1,500, from about 100 to about 1,250, or from about 100 to about 1,000. In certain embodiments, each z is independently an integer ranging from about 50 to about 2,000. In certain embodiments, each z is independently an integer ranging from about 100 to about 2,000. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,500. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,250. In certain embodiments, each z is independently an integer ranging from about 100 to about 1,000.

[0154] In certain embodiments, the moiety –A–L1–(CH2CH2O)s–Z (i.e., “PEG moiety”) has the structure of –NH(CH2CH2O)sCH2CH2OH, wherein each s is as defined herein. In certainAttorney Docket No.215A001WO01 embodiments, the PEG moiety has the structure of –NH(CH2CH2O)3CH2CH2OH. In certain embodiments, the PEG moiety has the structure of –NH(CH2CH2O)sCH2CH2SO3H, wherein each s is as defined herein. In certain embodiments, the PEG moiety has the structure of –NH(CH2CH2O)2CH2CH2SO3H. In certain embodiments, the PEG moiety has the structure of –NH(CH2CH2O)sCH2CH2CO2H, wherein each s is as defined herein. In certain embodiments, the PEG moiety has the structure of –NH(CH2CH2O)2CH2CH2CO2H.

[0155] In certain embodiments, the pegylated perfluorinated polymer provided herein has an EW ranging from about 50 to about 2,000, from about 100 to about 1,500, from about 200 to about 1,250, or from about 500 to about 1,250. In certain embodiments, the pegylated perfluorinated polymer provided herein has an EW ranging from about 50 to about 2,000. In certain embodiments, the pegylated perfluorinated polymer provided herein has an EW ranging from about 100 to about 1,500. In certain embodiments, the pegylated perfluorinated polymer provided herein has an EW ranging from about 200 to about 1,250. In certain embodiments, the pegylated perfluorinated polymer provided herein has an EW ranging from about 500 to about 1,250.

[0156] In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage of no greater than about 50%, no greater than about 40%, no greater than about 30%, or no greater than about 20%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage of no greater than about 50%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage of no greater than about 40%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage of no greater than about 30%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage of or no greater than about 20%.

[0157] In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage ranging from about 1 to about 50%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a graftingAttorney Docket No.215A001WO01 density in percentage ranging from about 2 to about 40%. In certain embodiments, the pegylated perfluorinated polymer provided herein has a grafting density in percentage ranging from about 5 to about 25%. In certain embodiments, a grafting density in percentage of a pegylated perfluorinated polymer provided herein is determined by an elemental analysis.

[0158] In certain embodiments, the pegylated perfluorinated polymer provided herein is a solid. In certain embodiments, the pegylated perfluorinated polymer provided herein is in the form of powders. In certain embodiments, the pegylated perfluorinated polymer provided herein is in the form of a polymer film.

[0159] In one embodiment, provided herein is a method of preparing a pegylated perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingthe presence of a base or a fluoride salt to form the pegylated perfluorinated polymer; wherein each E, L1, Z, m, p, q, and s is as defined herein.

[0160] In another embodiment, provided herein is a method of preparing a pegylated perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising the structure of: with a compound havingpresence of a base or a fluoride salt to form the pegylated perfluorinated polymer; wherein each E, L1, Z, m, p, q, s, and z is as defined herein.

[0161] In yet another embodiment, provided herein is a method of preparing a pegylatedAttorney Docket No.215A001WO01 perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain having the structure of: with a compound having presence of a base or afluoride salt to form the each E, L1, Z, m, n, p, q, s, and z is as defined herein.

[0162] In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is as defined herein. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is independently C1-6alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or butyl. In certain embodiments, each E is independently –OSi(R5)3, wherein each R5is methyl or tert-butyl. In certain embodiments, each E is independently trimethylsilyloxy or tert-butyldimethylsilyloxy. In certain embodiments, each E is trimethylsilyloxy. In certain embodiments, each E is tert- butyldimethylsilyloxy. In certain embodiments, each E is independently –NHR1b, wherein R1bis as defined herein. In certain embodiments, each E is –NH2.

[0163] In certain embodiments, each R5is independently C1-6 alkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl, ethyl, propyl, butyl, pentyl, or hexyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or butyl, each optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently methyl or tert-butyl. In certain embodiments, each R5is independently C1-6heteroalkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6 alkenyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C2-6 alkynyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C3-10cycloalkyl,Attorney Docket No.215A001WO01 optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C6-14 aryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently C7-15aralkyl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heteroaryl, optionally substituted with one or more substituents Q. In certain embodiments, each R5is independently heterocyclyl, optionally substituted with one or more substituents Q.

[0164] In certain embodiments, the pegylation step is performed in the presence of a base. In certain embodiments, the base is an organic base. In certain embodiments, the base is a nonnucleophilic base. In certain embodiments, the base is DBU, TBD, or BEMP. In certain embodiments, the base is DBU. In certain embodiments, the base is TBD. In certain embodiments, the base is BEMP. In certain embodiments, the base is DMAP or TEA. In certain embodiments, the base is DMAP. In certain embodiments, the base is TEA.

[0165] In certain embodiments, the pegylation step is performed in the presence of a fluoride salt. In certain embodiments, the fluoride salt is a bifluoride salt. In certain embodiments, the fluoride salt is cesium fluoride, tris(dimethylamino)sulfonium bifluoride, hexamethyl guanidium bifluoride, or tetrabutylammonium bifluoride. In certain embodiments, the fluoride salt is cesium fluoride. In certain embodiments, the fluoride salt is tris(dimethylamino)sulfonium bifluoride. In certain embodiments, the fluoride salt is hexamethyl guanidium bifluoride. In certain embodiments, the fluoride salt is tetrabutylammonium bifluoride.

[0166] In certain embodiments, the pegylation step is performed at a temperature ranging from about 20 to about 400 ºC, from about 25 to about 300 ºC, from about 50 to about 200 ºC, or from about 50 to about 100 ºC. In certain embodiments, the pegylation step is performed at a temperature ranging from about 20 to about 400 ºC. In certain embodiments, the pegylation step is performed at a temperature ranging from about 25 to about 300 ºC. In certain embodiments, the pegylation step is performed at a temperature ranging from about 50 to about 200 ºC. In certain embodiments, the pegylation step is performed at a temperature ranging from about 50 to about 100 ºC. In certain embodiments, the pegylation step is performed at about 50, about 60, about 70, about 80, about 90, or about 100 ºC.Attorney Docket No.215A001WO01

[0167] In certain embodiments, the pegylation step is performed in a solvent. In certain embodiments, the solvent is an aprotic solvent. In certain embodiments, the solvent is ACN, DMF, DMSO, NMP, THF, or a mixture thereof. In certain embodiments, the solvent is ACN. In certain embodiments, the solvent is DMF. In certain embodiments, the solvent is DMSO. In certain embodiments, the solvent is NMP. In certain embodiments, the solvent is THF.

[0168] In certain embodiments, the starting perfluorinated polymer (i.e., the perfluorinated polymer before pegylation) in a method provided herein is solid. In certain embodiments, the starting perfluorinated polymer in a method provided herein is in the form of powders. In certain embodiments, the starting perfluorinated polymer in a method provided herein is in the form of a polymer film.

[0169] In certain embodiments, the method provided herein further comprises the steps of converting the SO2F groups of the crosslinked perfluorinated polymer to sulfonate salt groups with a base (e.g., sodium hydroxide or potassium hydroxide) in a solvent (e.g., a mixture of DMSO and water); and converting the sulfonate salt groups to SO3H groups with an acid (e.g., nitric acid or sulfuric acid) in a solvent (e.g., a mixture of DMSO and water).

[0170] In certain embodiments, the compound (i.e., “PEG compound”) having the structure of E–L1–(CH2CH2O)s–Z is H2N(CH2CH2O)sCH2CH2OH, wherein each s is as defined herein. In certain embodiments, the PEG compound is H2N(CH2CH2O)3CH2CH2OH. In certain embodiments, the PEG compound is H2N(CH2CH2O)sCH2CH2SO3H, wherein each s is as defined herein. In certain embodiments, the PEG compound is H2N(CH2CH2O)2CH2CH2SO3H. In certain embodiments, the PEG compound is H2N(CH2CH2O)sCH2CH2CO2H, wherein each s is as defined herein. In certain embodiments, the PEG compound is H2N(CH2CH2O)2CH2CH2CO2H.

[0171] In certain embodiments, a pegylation perfluorinated polymer or a salt thereof prepared by a method provided herein has the structure of a pegylation perfluorinated polymer or a salt thereof provided herein.

[0172] In certain embodiments, provided herein is a pegylation perfluorinated polymer or a salt thereof prepared by a method provided herein.Attorney Docket No.215A001WO01

[0173] In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has an EW ranging from about 50 to about 2,000, from about 100 to about 1,500, from about 200 to about 1,250, or from about 500 to about 1,250. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has an EW ranging from about 50 to about 2,000. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has an EW ranging from about 100 to about 1,500. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has an EW ranging from about 200 to about 1,250. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has an EW ranging from about 500 to about 1,250.

[0174] In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of no greater than about 50%, no greater than about 40%, no greater than about 30%, no greater than about 20%, or no greater than about 10%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of no greater than about 50%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of no greater than about 40%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of no greater than about 30%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of or no greater than about 20%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage of or no greater than about 10%.

[0175] In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage ranging from about 1 to about 50%. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein has a grafting density in percentage ranging from about 2 to about 40%. In certain embodiments, the pegylatedAttorney Docket No.215A001WO01 perfluorinated polymer prepared by a method provided herein has a grafting density in percentage ranging from about 5 to about 25%.

[0176] In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein is solid. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein is in the form of powders. In certain embodiments, the pegylated perfluorinated polymer prepared by a method provided herein is in the form of a polymer film.

[0177] In certain embodiments, provided herein is a perfluorinated proton exchange membrane comprising a pegylated perfluorinated polymer or a salt thereof provided herein.

[0178] In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 1 to about 500 µm, from about 5 to about 300 µm, or from about 10 to about 200 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 1 to about 500 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 5 to about 300 µm. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a dry thickness ranging from about 10 to about 200 µm.

[0179] In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 25%, no greater than about 20%, no greater than about 15%, no greater than about 10%, or no greater than about 5%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 25%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 20%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 15%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 10%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio in plane of no greater than about 5%.

[0180] In certain embodiments, the perfluorinated proton exchange membrane providedAttorney Docket No.215A001WO01 herein has a swelling ratio (thickness) of no greater than about 25%, no greater than about 20%, no greater than about 15%, no greater than about 10%, or no greater than about 5%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 25%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 20%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 15%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 10%. In certain embodiments, the perfluorinated proton exchange membrane provided herein has a swelling ratio (thickness) of no greater than about 5%.

[0181] The disclosure will be further understood by the following non-limiting examples. EXAMPLES

[0182] As used herein, the symbols and conventions used in these processes, schemes and examples, regardless of whether a particular abbreviation is specifically defined, are consistent with those used in the contemporary scientific literature, for example, the Journal of the American Chemical Society or the Journal of Organic Chemistry. Specifically, but without limitation, the following abbreviations may be used in the examples and throughout the specification: g (grams); mg (milligrams); mL (milliliters); ^L (microliters); mM (millimolar); ^M (micromolar); mmol (millimoles); min (minute or minutes); h (hour or hours); ACN (acetonitrile); DBU (1,8-diazabicyclo[5.4.0]undec-7-ene); DCM (dichloromethane); TBS (tert- butyldimethylsilyl); TBSCl (tert-butyldimethylsilyl chloride); DSC (differential scanning calorimetry); EDS (energy dispersive spectroscopy); and FT-IR (Fourier-transform infrared spectroscopy).

[0183] For all of the following examples, standard work-up and purification methods known to those skilled in the art can be utilized. Unless otherwise indicated, all temperatures are expressed in ºC (degrees Centigrade). All reactions are conducted at room temperature unless otherwise specified. Synthetic methodologies illustrated herein are intended to exemplify the applicable chemistry through the use of specific examples and are not indicative of the scope of the disclosure.Attorney Docket No.215A001WO01 Example 1 Preparation of a polysiloxane-crosslinked NAFION-SO2F

[0184] A TBS-polydimethylsiloxane having the structure shown below was employed in crosslinking NAFION-SO2F, wherein r is an integer of about 9, about 10, about 22, or about 55.

[0185] of a polydimethyl- siloxane (MW ~1,000 g / mol -OH, 50 g, 50 mmol), TBSCl (9 g, 60 mmol) in DCM (500 mL) was added imidazole (4.1 g, 60 mmol) portion wise. After stirring at room temperature for 16 h, the reaction was quenched with 1M NaOH (300 mL). The organic layer was separated and washed with 1M NaOH (200 mL × 3), water (200 mL × 3), and brine (200 mL). The organic layer was then dried over anhydrous sodium sulfate and concentrated to afford the TBS- polydimethylsiloxane.

[0186] Preparation of a polysiloxane-crosslinked NAFION-SO2F. To a mixture of a NAFION-SO2F powder (100 mg, 0.1 mmol SO2F) and the TBS-polydimethylsiloxane (20 mg, 20 µmol) in anhydrous ACN (5 mL) was added DBU (16 mg, 0.1 mmol). The resulting suspension was heated at 80 ℃ for 24 h. The powder was collected by centrifugation and washed with ACN to afford the polysiloxane-crosslinked NAFION-SO2F powder.

[0187] The polysiloxane-crosslinked NAFION-SO2F powder was characterized by FT-IR and DSC. The FT-IR spectrum of the polysiloxane-crosslinked NAFION-SO2F powder shows the appearance of the Si-O-Si bond and the shift in the S(O2)-F stretching around 1,500 cm-1, indicating the successful crosslinking of the polymer chains of NAFION-SO2F. The DSC thermogram of the polysiloxane-crosslinked NAFION-SO2F powder shows the disappearance of the endothermic peak around 225 ℃ for the original NAFION-SO2F, also indicating the successful crosslinking of the polymer chains of NAFION-SO2F.

[0188] Based on the mole ratio of the NAFION-SO2F and TBS-polydimethylsiloxane used in the reaction above, the polysiloxane-crosslinked NAFION-SO2F was calculated to have aAttorney Docket No.215A001WO01 degree of crosslinking (DC) of about 6%. The DC of the polysiloxane-crosslinked NAFION- SO2F is determined by an elemental analysis. By varying the mole ratio of the TBS- polydimethylsiloxane versus NAFION-SO2F, polysiloxane-crosslinked NAFION-SO2F with a DC ranging from about 6 to about 20% was prepared.

[0189] Preparation of polysiloxane-crosslinked NAFION-SO3H. The polysiloxane- crosslinked NAFION-SO2F powder was treated with KOH in DMSO and water at 80 ℃ for 8 h. The powder was collected by centrifugation and washed with water to afford polysiloxane- crosslinked NAFION-SO3K, which was immersed in 1M HNO3 at room temperature to afford the polysiloxane-crosslinked NAFION-SO3H.

[0190] The polysiloxane-crosslinked NAFION-SO3H was analyzed by EDS. The resulting EDS mapping indicates the presence of silicon elements, suggesting that the polysiloxane chains remained intact and were not adversely affected by the hydrolysis conditions.

[0191] Polysiloxane-crosslinked NAFION-SO2F and NAFION-SO3H films with a DC ranging from about 6 to about 20% were also prepared similarly from a NAFION-SO2F film. Example 2 Preparation of polysiloxane-crosslinked NAFION-SO2F and NAFION-SO3H

[0192] Bis(3-aminopropyl) terminated poly(dimethylsiloxane) having the structure shown below was employed in crosslinking NAFION-SO2F, wherein r is an integer of about 9, about 10, about 22, or about 55.

[0193] Preparation of polysiloxane-crosslinked NAFION-SO2F. To a mixture of NAFION-SO2F powder (100 mg, 0.1 mmol SO2F) and bis(3-aminopropyl) terminated poly(dimethylsiloxane) (MW ~2000 g / mol -NH2, 40 mg, 20 µmol) in anhydrous ACN (5 mL) was added DBU (16 mg, 0.1 mmol). The resulting suspension was heated at 80 ℃ for 24 h. TheAttorney Docket No.215A001WO01 powder was collected by centrifugation and washed with ACN to afford the polysiloxane- crosslinked NAFION-SO2F powder.

[0194] The polysiloxane-crosslinked NAFION-SO2F was characterized by FT-IR and DSC. The FT-IR spectrum of the polysiloxane-crosslinked NAFION-SO2F in FIG.1 shows the appearance of the Si-O bond and the shift in the S(O2)-F stretching around 1,500 cm-1, indicating the successful crosslinking of the polymer chains of NAFION-SO2F. The DSC thermogram of the polysiloxane-crosslinked NAFION-SO2F in FIG.2 shows the disappearance of the endothermic peak around 225 ℃ for the original NAFION-SO2F, also indicating the successful crosslinking of the polymer chains of NAFION-SO2F.

[0195] Based on the mole ratio of the NAFION-SO2F and bis(3-aminopropyl) terminated poly(dimethylsiloxane) used in the reaction above, the polysiloxane-crosslinked NAFION-SO2F was calculated to have a degree of crosslinking (DC) of about 20%. The DC of the polysiloxane- crosslinked NAFION-SO2F is determined by an elemental analysis. By varying the mole ratio of bis(3-aminopropyl) terminated poly(dimethylsiloxane) versus NAFION-SO2F, polysiloxane- crosslinked NAFION-SO2F with a DC ranging from about 6 to about 20% was prepared.

[0196] Preparation of polysiloxane-crosslinked NAFION-SO3H. A mixture of the polysiloxane-crosslinked NAFION-SO2F powder (100 mg) and KOH (150 mg) in DMSO (350 mg) and water (500 mg) was heated at 80 ℃ for 8 h. The powder was collected by centrifugation and washed with water to afford polysiloxane-crosslinked NAFION-SO3K, which was immersed in 1M HNO3at room temperature to afford the polysiloxane-crosslinked NAFION-SO3H.

[0197] The polysiloxane-crosslinked NAFION-SO3H was analyzed by EDS. The resulting EDS mapping indicates the presence of silicon elements, suggesting that the polysiloxane chains remained intact and were not adversely affected by the hydrolysis conditions.

[0198] Polysiloxane-crosslinked NAFION-SO2F and NAFION-SO3H films with a DC ranging from about 6 to about 20% were also prepared similarly from a NAFION-SO2F film.Attorney Docket No.215A001WO01 Example 3 Preparation of pegylated NAFION-SO2F

[0199] Preparation of pegylated NAFION-SO2F. To a mixture of NAFION-SO2F powder (100 mg, 0.1 mmol SO2F) and tetraethylene glycol monoamine (MW ~2000 g / mol -NH2, 40 mg, 20 µmol) in anhydrous ACN (5 mL) was added DBU (16 mg, 0.1 mmol). The resulting suspension was heated at 80 ℃ for 24 h. The powder was collected by centrifugation and washed with ACN to afford the pegylated NAFION-SO2F powder.

[0200] The pegylated NAFION-SO2F powder was characterized by FT-IR and DSC. The FT-IR spectrum of the pegylated NAFION-SO2F powder in FIG.5 shows the appearance of C-O stretching and a shift in the S-F stretching around 1500 cm-1, indicating the successful pegylation of the polymer chain of NAFION-SO2F. The DSC thermogram of the pegylated NAFION-SO2F powder in FIG.6 shows a decrease in the exothermic peak by approximately 20 ºC, suggesting that NAFION-SO2F has become easier to process after pegylation.

[0201] Based on the mole ratio of the NAFION-SO2F and tetraethylene glycol monoamine used in the reaction above, the pegylated NAFION-SO2F was calculated to have a grafting density in percentage of about 20%. The grafting density in percentage of the pegylated NAFION-SO2F is determined by an elemental analysis. By varying the mole ratio of tetraethylene glycol monoamine versus NAFION-SO2F, pegylated NAFION-SO2F with a grafting density in percentage ranging from about 6 to about 20% was prepared.

[0202] Preparation of pegylated NAFION-SO3H. The pegylated NAFION-SO2F powder was treated with KOH in DMSO and water at 80 ℃ for 8 h. The powder was collected by centrifugation and washed with water to afford pegylated NAFION-SO3K, which was immersed in 1M HNO3at room temperature to afford the pegylated NAFION-SO3H.

[0203] The pegylated NAFION-SO3H powder was analyzed by EDS. The resulting EDS mapping indicates the presence of silicon elements, suggesting that the polysiloxane chains remained intact and were not adversely affected by the hydrolysis conditions.

[0204] Pegylated NAFION-SO2F and NAFION-SO3H films with a grafting density in percentage ranging from about 6 to about 20% were also prepared similarly from a NAFION-Attorney Docket No.215A001WO01 SO2F film.

[0205] Unlike the unmodified NAFION-SO3H, the pegylated NAFION-SO3H was effectively dispersed in a mixture of water and isopropyl alcohol (IPA), forming a 2.5% by weight solution. This solution was clear and homogenous, displaying a pronounced Tyndall effect. When the dispersion of the pegylated NAFION-SO3H was used as a binder in the preparation of an electrode, excellent electrochemical stability was observed during repeated cyclic voltammetry (CV) tests conducted at a scan rate of 100 mV / s. No changes in the shape or position of the peaks were observed throughout the testing, indicating a high level of stability with no evidence of degradation. The pegylated NAFION-SO3H demonstrated significantly higher dispersibility compared to commercial NAFION-SO3H under the same conditions. Example 4 Electrochemical Evaluation

[0206] Crosslinked and pegylated NAFION-SO3H were each independently heat-pressed to form a continuous film. Each film was evaluated for its performance as a PFSA proton exchange membrane in a fuel cell in comparison with commercial NAFION-115 under identical conditions. Before testing, all membranes were pre-soaked for 72 h to ensure full hydration, which is essential for the proton transport mechanism within the membrane matrix. Proton conductivity was then measured by applying a consistent voltage of 10 mV across the membrane at various temperatures to evaluate the impact of thermal variables on proton conductivity. The results are shown in Table 1, where Pegylated-1 membrane was prepared from pegylated NAFION-SO3H powders with a calculated grafting density in percentage of about 20%; Pegylated-2 membrane was prepared from a pegylated NAFION-SO3H film with a calculated grafting density in percentage of about 20%; and Crosslinked-1 membrane was prepared a crosslinked NAFION-SO3H with a calculated DC of about 20%.

[0207] Compared to commercial NAFION-115, both crosslinked and pegylated NAFION-SO3H membranes showed lower swelling ratios. Although Pegylated-1 membrane showed similar water uptake to commercial NAFION-115, its in-plane swelling ratio was only half that of NAFION-115, and its thickness swelling was only 8%, showing an almost five-fold decrease compared to NAFION-115. The reduced swelling of Pegylated-1 membrane suggestsAttorney Docket No.215A001WO01 that the membrane maintains its dimensional stability better than commercial NAFION-115 when hydrated. Reduced swelling in a fuel cell membrane is highly desired because it directly influences the membrane’s mechanical stability and durability under operational conditions. At 70 ºC, the Pegylated membrane demonstrated a nearly 2-fold increase in conductivity, rising from 37 ms / cm to 72 ms / cm, in comparison with commercial NAFION-115. Table 1 Material Swelling Ratio Swelling Ratio Water Temp. Proton Conductivity Type in plane (%) Thickness (%) Uptake (%) (°C) (mS / cm)

[0208] The examples set forth above are provided to give those of ordinary skill in the art with a complete disclosure and description of how to make and use the claimed embodiments and are not intended to limit the scope of what is disclosed herein. Modifications that are obvious to persons of skill in the art are intended to be within the scope of the following claims. All publications, patents, and patent applications cited in this specification are incorporated herein by reference as if each such publication, patent or patent application were specifically and individually indicated to be incorporated herein by reference.

Claims

Attorney Docket No.215A001WO01 What is claimed is:

1. A crosslinked perfluorinated polymer or a salt thereof, wherein the crosslinked perfluorinated polymer comprises two or more polymeric chains, each polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of Formula (I): wherein:the two or more are one or more divalent crosslinkers, each divalent crosslinker having the structure of , wherein oneA is attached to a repeating unit of a polymeric chain at the X position and the A is attached to a repeating unit of a different polymeric chain at the X position as such that the two X are paired together to form a divalent crosslinker; and free X groups are each independently halo, –OR1a, or –NR1bR1c; each A is independently –O– or ––N(R1b)–; each L is independently a bond, C1-15 alkylene, C1-15 heteroalkylene, C2-10 alkenylene, C2-10alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene; each R1, R2, R3, and R4is independently C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6 alkynyl, C3-6 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; and each r is independently an integer ranging from about 1 to about 100 or from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl,Attorney Docket No.215A001WO01 alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc, –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2F, –NRaS(O)2Rd, –NRaS(O)2ORd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2F, –S(O)2Ra, –S(O)2ORa, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14 aryl, C7-15 aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)2F, –NReS(O)Rh, –NReS(O)2ORh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2F, –S(O)2Re, –S(O)2ORe, –S(O)NRfRg, and –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached formAttorney Docket No.215A001WO01 heterocyclyl.

2. The crosslinked perfluorinated polymer or a salt thereof of claim 1, wherein each perfluorinated polymeric chain comprises the structure of Formula (II): wherein z is an integer3. The crosslinked perfluorinated polymer or a salt thereof of claim 1 or 2, wherein each perfluorinated polymeric chain has the structure of Formula (III): wherein each n is50; and z is an integer ranging from about 10 to about 2,000.

4. The crosslinked perfluorinated polymer or a salt thereof of claim 3, wherein each n is independently an integer ranging from about 1 to about 20.

5. The crosslinked perfluorinated polymer or a salt thereof of claim 3 or 4, wherein each n is independently an integer of 4, 5, 6, 7, or 8.

6. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 2 to 5, wherein each z is independently an integer ranging from about 100 to about 1,250.

7. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 6, wherein each A is –O–.

8. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 6, wherein each A is –N(H)–.

9. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 toAttorney Docket No.215A001WO01 8, wherein each L is independently (i) a bond; or (ii) C1-10 alkylene or C1-10 heteroalkylene, each optionally substituted with one or more substituents Q.

10. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9, wherein each L is a bond.

11. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9, wherein each L is independently C1-10alkylene, optionally substituted with one or more substituents Q.

12. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9 and 11, wherein each L is independently L is methane-1,1-diyl, ethane-1,2-diyl, propane-1,3- diyl, butane-1,4-diyl, pentane-1,5-diyl, or hexane-1,6-diyl, each optionally substituted with one or more substituents Q.

13. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9, wherein each L is independently C1-10heteroalkylene, optionally substituted with one or more substituents Q.

14. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9 and 13, wherein each L is independently C1-6alkylene–O–C1-6alkylene or C1-6alkylene–S–C1-6alkylene, each optionally substituted with one or more substituents Q.

15. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 9, wherein L is a bond, ethane-1,2-diyl, propane-1,3-diyl, –CH2CH2OCH2CH2CH2–, or –CH2CH2–S–CH2CH2–.

16. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 15, wherein the moiety –A–L– is –O–, –OCH2CH2OCH2CH2–, –OCH2CH2OCH2CH2CH2–, –OCH2CH2SCH2CH2–, or –N(H)CH2CH2CH2–.

17. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 16, wherein each R1is independently C1-6 alkyl or C1-6 heteroalkylene, each optionally substituted with one or more substituents Q.Attorney Docket No.215A001WO01 18. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 17, wherein each R1is independently methyl or 3,3,3-trifluoropropyl.

19. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 18, wherein each R1is methyl.

20. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 19, wherein each R2is independently C1-6alkyl or C1-6heteroalkylene, each optionally substituted with one or more substituents Q.

21. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 20, wherein each R2is independently methyl or 3,3,3-trifluoropropyl.

22. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 21, wherein each R2is methyl.

23. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 22, wherein each R3is independently C1-6alkyl or C1-6heteroalkylene, each optionally substituted with one or more substituents Q.

24. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 23, wherein each R3is independently methyl or 3,3,3-trifluoropropyl.

25. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 24, wherein each R3is methyl.

26. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 25, wherein each R4is independently C1-6alkyl or C1-6heteroalkylene, each optionally substituted with one or more substituents Q.

27. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 26, wherein each R4is independently methyl or 3,3,3-trifluoropropyl.

28. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 27, wherein each R4is methyl.Attorney Docket No.215A001WO01 29. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 27, wherein each R4is 3,3,3-trifluoropropyl.

30. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 29, wherein each m is independently an integer ranging from about 1 to about 20.

31. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 30, wherein each m is independently each m is independently an integer of 4, 5, 6, 7, or 8.

32. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 31, wherein each p is independently an integer of 0, 1, 2, or 3.

33. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 32, wherein each p is an integer of 0.

34. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 32, wherein each p is an integer of 1.

35. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 34, wherein each q is independently an integer of 1, 2, 3, 4, or 5.

36. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 35, wherein each p is an integer of 2.

37. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 35, wherein each p is an integer of 4.

38. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 37, wherein each r is independently an integer ranging from about 5 to about 60.

39. A method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of:Attorney Docket No.215A001WO01with a compound having the structure in the presence of a base or a fluoride salt to form theeach E is independently –OSi 3 or each R5is independently C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, R1b, L, Q, m, p, q, and r is as defined in claim 1.

40. The method of claim 39, wherein the base is an organic base.

41. The method of claim 39 or 40, wherein the base is 1,8-diazabicyclo[5.4.0]undec- 7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, or 2-tert-butylimino-2-diethylamino-1,3-dimethyl- perhydro-1,3,2-diazaphosphorine.

42. A method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingof a base or a fluoride salt to form a functionalized polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of:Attorney Docket No.215A001WO01 wherein at least one Xaand the remainingXagroups are each fluoro; (b) reacting the functionalized polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedwherein: each E is independently –OSi(R5)3 or –NHR1b; each R5is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; each Laand Lbis independently C1-6 alkylene, C1-6 heteroalkylene, C2-6 alkenylene, C2-6 alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, R1b, Q, m, p, q, and r is as defined in claim 1.

43. A method of preparing a crosslinked perfluorinated polymer or a salt thereof, comprising the steps of: (a) reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of: with a compound havingof a base or a fluoride salt to form a functionalized polymer having a polymeric chain comprising two or more repeating units, each repeating unit having the structure of:Attorney Docket No.215A001WO01 wherein at least one Xaand the remaining aX groups are each fluoro; (b) converting the SO2F groups of the functionalized polymer to sulfonate salt groups with a base; (c) converting the sulfonate salt groups of the functionalized polymer to SO3H groups with an acid; and (d) reacting the functionalized perfluorinated polymer with a compound having the structure of in the presence of a radical initiator to form the crosslinkedeach E is independently –OSi(R5)3 or –NHR1b; each R5is independently C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; each Laand Lbis independently C1-6 alkylene, C1-6 heteroalkylene, C2-6 alkenylene, C2-6 alkynylene, C3-10cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene, each optionally substituted with one or more substituents Q; and each R1, R2, R3, R4, R1b, Q, m, p, q, and r is as defined in claim 1.

44. The method of claim 42 or 43, wherein each Lais independently C1-6alkylene or C1-6heteroalkylene, each optionally substituted with one or more substituents Q.

45. The method of any one of claims 42 to 44, wherein each Lais independently ethane-1,2-diyl or propane-1,3-diyl.

46. The method of any one of claims 42 to 45, wherein each Lbis independently C1-6alkylene or C1-6 heteroalkylene, each optionally substituted with one or more substituents Q.

47. The method of any one of claims 42 to 46, wherein each Lbis independentlyAttorney Docket No.215A001WO01 methane-1,1-diyl or ethane-1,2-diyl.

48. The method of any one of claims 42 to 47, wherein the base in step (a) is an organic base.

49. The method of any one of claims 42 to 48, wherein the base in step (a) is 1,8- diazabicyclo-[5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, or 2-tert-butylimino-2- diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine.

50. The method of any one of claims 42 to 49, wherein the radical initiator is a photoinitiator.

51. The method of any one of claims 42 to 50, wherein the radical initiator is azobisisobutyronitrile, 1,1’-azobis(cyclohexanecarbonitrile), or 2,2-dimethoxy-2- phenylacetonephenone.

52. The method of any one of claims 39 to 51, wherein each E is independently –OSi(R5)3.

53. The method of claim 52, wherein each R5is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q.

54. The method of any one of claims 39 to 53, wherein each E is independently trimethylsilyloxy or tert-butyldimethylsilyloxy.

55. The method of any one of claims 39 to 51, wherein each E is –NH2.

56. A crosslinked perfluorinated polymer or a salt thereof produced by a method of any one of claims 39 to 55.

57. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 38 and 56, having an equivalent weight (EW) ranging from about 50 to about 2,000.

58. The crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 38.56, and 57, having a degree of crosslinking ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%.Attorney Docket No.215A001WO01 59. A perfluorinated proton exchange membrane comprising a crosslinked perfluorinated polymer or a salt thereof of any one of claims 1 to 38 and 56 to 58.

60. A pegylated perfluorinated polymer or a salt thereof, wherein the pegylated perfluorinated polymer has a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of Formula (I): wherein:at least one X group a structure of –A–L1–(CH2CH2O)s–Z; and the remaining X groups are each independently halo, –OR1a, or –NR1bR1c; A is –O– or –N(R1b)–; L1is a bond, C1-10 alkylene, C1-10 heteroalkylene, C2-10 alkenylene, C2-10 alkynylene, C3-10 cycloalkylene, C6-14arylene, C7-15aralkylene, heteroarylene, or heterocyclylene; Z is hydrogen, C1-6 alkyl, C1-6 heteroalkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6- 14 aryl, C7-15 aralkyl, heteroaryl, or heterocyclyl; each R1a, R1b, and R1cis independently hydrogen, C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-6cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; each m is independently an integer ranging from about 1 to about 50; each p is independently an integer of 0, 1, 2, 3, 4, or 5; each q is independently an integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; and each s is independently an integer of ranging from about 1 to about 50; wherein each alkyl, alkylene, heteroalkyl, heteroalkylene, alkenyl, alkenylene, alkynyl, alkynylene, cycloalkyl, cycloalkylene, aryl, arylene, aralkyl, aralkylene, heteroaryl, heteroarylene, heterocyclyl, and heterocyclylene is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Q, wherein each Q is independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl, each of which is further optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; and (c) –C(O)Ra, –C(O)ORa, –C(O)NRbRc, –C(O)SRa, –C(NRa)NRbRc,Attorney Docket No.215A001WO01 –C(S)Ra, –C(S)ORa, –C(S)NRbRc, –ORa, –OC(O)Ra, –OC(O)ORa, –OC(O)NRbRc, –OC(O)SRa, –OC(NRa)NRbRc, –OC(S)Ra, –OC(S)ORa, –OC(S)NRbRc, –OS(O)Ra, –OS(O)2Ra, –OS(O)NRbRc, –OS(O)2NRbRc, –NRbRc, –NRaC(O)Rd, –NRaC(O)ORd, –NRaC(O)NRbRc, –NRaC(O)SRd, –NRaC(NRd)NRbRc, –NRaC(S)Rd, –NRaC(S)ORd, –NRaC(S)NRbRc, –NRaS(O)Rd, –NRaS(O)2Rd, –NRaS(O)NRbRc, –NRaS(O)2NRbRc, –SRa, –S(O)Ra, –S(O)2Ra, –S(O)NRbRc, and –S(O)2NRbRc, wherein each Ra, Rb, Rc, and Rdis independently (i) hydrogen or deuterium; (ii) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each of which is optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; or (iii) Rband Rctogether with the N atom to which they are attached form heterocyclyl, optionally substituted with one or more, in one embodiment, one, two, three, or four, substituents Qa; wherein each Qais independently selected from: (a) deuterium, cyano, halo, nitro, and oxo; (b) C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, and heterocyclyl; and (c) –C(O)Re, –C(O)ORe, –C(O)NRfRg, –C(O)SRe, –C(NRe)NRfRg, –C(S)Re, –C(S)ORe, –C(S)NRfRg, –ORe, –OC(O)Re, –OC(O)ORe, –OC(O)NRfRg, –OC(O)SRe, –OC(NRe)NRfRg, –OC(S)Re, –OC(S)ORe, –OC(S)NRfRg, –OS(O)Re, –OS(O)2Re, –OS(O)NRfRg, –OS(O)2NRfRg, –NRfRg, –NReC(O)Rh, –NReC(O)ORf, –NReC(O)NRfRg, –NReC(O)SRf, –NReC(NRh)NRfRg, –NReC(S)Rh, –NReC(S)ORf, –NReC(S)NRfRg, –NReS(O)Rh, –NReS(O)2Rh, –NReS(O)NRfRg, –NReS(O)2NRfRg, –SRe, –S(O)Re, –S(O)2Re, –S(O)NRfRg, and –S(O)2NRfRg; wherein each Re, Rf, Rg, and Rhis independently (i) hydrogen or deuterium; (ii) C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-10 cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl; or (iii) Rfand Rgtogether with the N atom to which they are attached form heterocyclyl.

61. The pegylated perfluorinated polymer or a salt thereof of claim 60, wherein each polymeric chain comprises the structure of Formula (II): wherein z is an integerAttorney Docket No.215A001WO01 62. The pegylated perfluorinated polymer or a salt thereof of claim 60 or 61, wherein each polymeric chain has the structure of Formula (III): wherein n is an integer ranging from about10 to about 2,000.

63. The pegylated perfluorinated polymer or a salt thereof of claim 62, wherein each n is independently an integer ranging from about 1 to about 20.

64. The pegylated perfluorinated polymer or a salt thereof of claim 62 or 63, wherein each n is independently an integer of 4, 5, 6, 7, or 8.

65. The pegylated perfluorinated polymer or a salt thereof of any one of claims 61 to 64, wherein each z is independently an integer ranging from about 100 to about 1,250.

66. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 65, wherein each A is –O–.

67. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 65, wherein each A is –N(H)–.

68. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 67, wherein each L1is independently (i) a bond; or (ii) C1-10alkylene or C1-10heteroalkylene, each optionally substituted with one or more substituents Q.

69. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 68, wherein each L1is a bond.

70. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 68, wherein each L1is independently C1-10 alkylene, optionally substituted with one or more substituents Q.Attorney Docket No.215A001WO01 71. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 68 and 70, wherein each L1is independently ethane-1,2-diyl or propane-1,3-diyl, each optionally substituted with one or more substituents Q.

72. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 68, wherein the moiety –A–L1– is –O–, –N(H)CH2CH2–, or –N(H)CH2CH2CH2–.

73. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 72, wherein each Z is independently (i) hydrogen; or (ii) C1-6alkyl or C1-6heteroalkyl, each optionally substituted with one or more substituents Q.

74. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 73, wherein each Z is independently C1-6alkyl, optionally substituted with –C(O)ORa, –C(O)NRbRc, –S(O)2ORa, or –S(O)2NRbRc.

75. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 74, wherein each Z is independently each Z is independently methyl, –CH2SO3H, or –CH2CH2CO2H.

76. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 75, wherein each m is independently an integer ranging from about 1 to about 20.

77. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 76, wherein each m is independently each m is independently an integer of 4, 5, 6, 7, or 8.

78. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 77, wherein each p is independently an integer of 0, 1, 2, or 3.

79. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 78, wherein each p is an integer of 0.

80. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 79, wherein each p is an integer of 1.

81. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 toAttorney Docket No.215A001WO01 80, wherein each q is independently an integer of 1, 2, 3, 4, or 5.

82. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 81, wherein each p is an integer of 2.

83. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 81, wherein each p is an integer of 4.

84. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 83, wherein each s is independently an integer ranging from about 1 to about 20.

85. A method of preparing a pegylated perfluorinated polymer or a salt thereof, comprising the step of reacting a perfluorinated polymer having a polymeric chain comprising two or more repeating units, each repeating unit comprising the structure of: with a compound havingthe presence of a base or a fluoride salt to form the pegylated perfluorinated polymer; wherein: E is –OSi(R5)3 or –NHR1b; each R5is independently C1-6alkyl, C1-6heteroalkyl, C2-6alkenyl, C2-6alkynyl, C3-10cycloalkyl, C6-14aryl, C7-15aralkyl, heteroaryl, or heterocyclyl, each optionally substituted with one or more substituents Q; and each R1b, L1, Z, m, p, q, and s is as defined in claim 60.

86. The method of claim 85, wherein E is –OSi(R5)3.

87. The method of claim 85 or 86, wherein each R5is independently C1-6 alkyl or C1-6 heteroalkyl, each optionally substituted with one or more substituents Q.

88. The method of any one of claims 85 to 87, wherein E is trimethylsilyloxy or tert- butyldimethylsilyloxy.

89. The method of claim 85, wherein E is –NH2.Attorney Docket No.215A001WO01 90. The method of any one of claims 85 to 89, wherein the base is an organic base.

91. The method of any one of claims 85 to 90, wherein the base is 1,8-diazabicyclo- [5.4.0]undec-7-ene, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, or 2-tert-butylimino-2-diethylamino- 1,3-dimethylperhydro-1,3,2-diazaphosphorine.

92. A pegylated perfluorinated polymer or a salt thereof produced by a method of any one of claims 85 to 91.

93. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 84 and 92, having an equivalent weight (EW) ranging from about 50 to about 2,000.

94. The pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 84 and 92, having a grafting density in percentage ranging from about 1 to about 50%, from about 2 to about 40%, or from about 5 to about 25%.

95. A perfluorinated proton exchange membrane comprising a pegylated perfluorinated polymer or a salt thereof of any one of claims 60 to 84 and 92 to 94.

Images