Zwitterionic charged copolymer membrane

Abstract

Disclosed are linear / random / statistical copolymers comprising three types of monomer units: hydrophobic monomer units, zwitterionic monomer units, and charged or ionizable monomer units. Also provided are thin film composite membranes having a selective layer comprising the copolymers disclosed herein and methods of using the same.

Description

[0001] Related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 846,014, filed May 10, 2019, the contents of which are incorporated herein by reference in their entirety.

[0003] Government support

[0004] This invention was made with Government support under Grants 1508049 and 1553661 awarded by the National Science Foundation. The Government has certain rights in this invention. Background Art

[0005] Nanofiltration (NF) membranes are defined by an effective pore size of approximately 1 nm. They are commonly used to remove divalent salts from water and wastewater streams in applications such as water softening. Nearly all commercial NF membranes on the market today feature a cross-linked polyamide selective layer produced by interfacial polymerization. This selective layer chemistry has been used for decades, and as a result, these commercial membranes are well optimized and offer reasonably high water permeability and the desired divalent salt rejection.

[0006] However, polyamide selective layers also have significant limitations inherent to their chemical structure, such as a lack of fouling resistance and chlorine tolerance. In recent years, zwitterions have attracted extensive research in the membrane field due to their hydrophilicity and fouling resistance. Zwitterionic amphiphilic copolymers (ZACs) have been documented to self-assemble to form microstructures. When ZACs are used as membrane selective layers, fouling-resistant membranes with effective pore sizes of approximately 1-2 nm can be achieved. These membranes also exhibit high chlorine resistance.

[0007] However, a key characteristic of these membranes is that they exhibit relatively low salt rejection due to the overall neutral chemistry of the membrane's selective layer. Therefore, while ZACs offer good fouling and chlorine resistance, along with effective pore sizes approaching those of NF membranes, their rejection characteristics are insufficient to replace commercial NF membranes in most applications. Therefore, there is a need to develop high-performance membranes that do not exhibit these drawbacks. Summary of the Invention

[0008] This paper provides a copolymer comprising each of a plurality of three types of monomeric units: a hydrophobic monomeric unit, a zwitterionic monomeric unit and a charged or ionizable monomeric unit. Preferably, the copolymer is linear, statistical or random, or all of them. A thin film composite membrane is also provided, wherein its selectivity layer is made up of these copolymers. These membranes can be used for multiple aqueous separations, including but not limited to the separation and purification of organic molecules in water treatment, water softening, wastewater treatment and the aqueous solution. Due to the chemical properties of these copolymers, the membrane shows improved resistance to chlorine chemical degradation and powerful anti-fouling properties.

[0009] In one aspect, provided herein are copolymers comprising a plurality of zwitterionic monomeric units, a plurality of charged / ionizable monomeric units, and a plurality of hydrophobic monomeric units.

[0010] In yet another aspect, provided herein is a thin film composite membrane comprising a porous support and a thin film of a polymeric material, wherein the porous support has a pore size that is larger than the effective pore size of the thin film of the polymeric material.

[0011] In another aspect, provided herein are methods of size-based selection or exclusion comprising contacting a solution comprising a plurality of uncharged organic molecules of different sizes with a thin film composite membrane disclosed herein.

[0012] In yet another aspect, provided herein are methods of charge-based selection or exclusion comprising contacting a solution comprising a plurality of salts with a thin film composite membrane disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A scheme depicting the polymer structure / chemistry of a charged zwitterionic amphiphilic copolymer (CZAC), P(TFEMA-r-SBMA-r-MAA), and a schematic description of its self-assembly when coated onto a support to form a membrane selective layer having hydrophilic domains of approximately 1-2 nm that serve as an efficient nanochannel network lined with carboxylate groups.

[0014] Figure 2 Describing PTFEMA-SBMA-MAA-B1 1 HNMR spectroscopy indicated copolymerization.

[0015] Figure 3 Describing PTFEMA-SBMA-MAA-B2 1 H NMR spectroscopy indicated copolymerization.

[0016] Figure 4A Depicted is an SEM image of an uncoated Trisep UE50 support film.

[0017] Figure 4B Depicted is the SEM image of the PTFEMA-SBMA-MAA-B1 TFC membrane.

[0018] Figure 4C Depicting the SEM image of the PTFEMA-SBMA-MAA-B2 TFC membrane.

[0019] Figure 5ABar graphs depicting the rejection of neutral (Rib, RH, and VB12) and anionic (Na2SO4, MO, AB45) solutes by PTFEMA-SBMA membrane, PTFEMA-SBMA-MAA-B1 membrane, and PTFEMA-SBMA-MAA-B2 membrane.

[0020] Figure 5B is a graph depicting the rejection of sugars and dyes by membranes prepared as described in Example 2B.

[0021] Figure 6A The retention of various salts at 1 mM and 5 mM concentrations by the PTFEMA-SBMA membrane, the PTFEMA-SBMA-MAA-B1 membrane, and the PTFEMA-SBMA-MAA-B2 membrane is depicted.

[0022] Figure 6B The results show that PTFEMA-SBMA-MAA-B1 has a strong affinity for Na2SO4(C 进料 = 5 mM).

[0023] Figure 6C is a bar graph depicting the retention of PTFEMA-SBMA-MAA-B2 for various salts at concentrations of 1 mM and 5 mM. The retention was fitted to DSPM (for C 进料 =1mM:D 孔 =1.95nm,δ 有效 = 20 μm, and X = 21.4 mM. For C 进料 =5mM:D 孔 =1.95nm,δ 有效 =20 μm, and X=60.4 mM).

[0024] Figure 7A is a bar graph depicting the rejection of various neutral dyes.

[0025] Figure 7B is a bar graph depicting the retention of various anionic dyes and Na2SO4.

[0026] Figure 8A is a graph depicting the antifouling properties of PTFEMA-SBMA-MAA-B2 membranes (stabilized by Span 80 neutral surfactant) against oil emulsions;

[0027] Figure 8B is a graph depicting the oil emulsion fouling resistance of PTFEMA-SBMA-MAA-B2 membranes stabilized by DC 193 neutral surfactant.

[0028] Figure 8Cis a graph depicting the antifouling properties of CZAC membranes against a mixture of BSA and CaCl2 (1.0 g / L BSA, 10 mM CaCl2 (pH=6.3) and J0 5.4 LMH). A commercial NF membrane was used as a benchmark.

[0029] Figure 8D is a graph depicting the fouling resistance of CZAC membranes against a mixture of humic acid and alginate (1 g / L each, pH 4.5, J0 = 7.0 LMH).A commercial NF membrane was used as a benchmark.

[0030] Figure 9 is a graph depicting the permeability of PTSBMA-SBMA-MAA before and after Clorox treatment.

[0031] Figure 10 FTIR spectra depicting the effect of chlorine treatment on the bond chemistry of PTFEMA-SBMA-MAA-B2. FTIR spectra taken before and after immersion in a 2,000 ppm sodium hypochlorite solution at pH 4.5 for 16 hours.

[0032] Figure 11 is a graph depicting the rearrangement of PTFEMA-SBMA-MAA-B1 upon exposure to PBS solution, followed by the observed switchable flux behavior.

[0033] Figure 12A Is to describe NaOH (aq) Bar graph of the rearrangement of PTFEMA-SBMA-MAA-B1 membrane (pH=11).

[0034] Figure 12B is depicted in NaOH (aq) (pH=11) Bar graph of the permeability of PTFEMA-SBMA membrane during filtration.

[0035] Figure 13 is depicted in the presence of NaOH (aq) Bar graphs of retention of vitamin B12 and Na2SO4 before and after treatment rearrangement.

[0036] Figure 14 is a bar graph depicting membrane permeability versus filter ID (from Table 5).

[0037] Figure 15 is a bar graph depicting the permeability of the rearranged PTFEMA-SBMA-MAA membrane in response to a calcium-containing alkaline solution.

[0038] Figure 16 is a graph depicting the correlation between the composition of the reaction mixture and the composition of the resulting terpolymer, indicating a near random monomer sequence. DETAILED DESCRIPTION

[0039] Disclosed are membranes that combine NF-type selectivity with fouling resistance and chlorine resistance by exploiting the self-assembly properties of ZAC and modifying this polymer family to improve salt rejection. Specifically, disclosed are charged zwitterionic amphiphilic copolymers (CZAC) and membranes with CZAC selective layers prepared by scalable manufacturing techniques. CZAC is a random or statistical terpolymer of three types of monomers: a hydrophobic monomer, a zwitterionic monomer, and an acidic / ionizable monomer. Preferably, the copolymer is linear, random, and statistical. The random / statistical structure and zwitterionic-zwitterionic attraction of the copolymer enable this terpolymer to self-assemble into a bicontinuous network consisting of 1-2 nm hydrophilic (zwitterionic / charged) and hydrophobic nanodomains. Water and other solutes pass through the hydrophilic domains, which act as an effective network of nanochannels with charged walls. This allows the terpolymer to act as a membrane selective layer. Due to the ionization of incorporated functional groups (e.g., deprotonation of acidic repeat units, protonation of amine groups, and dissociation of sulfonate groups), the hydrophilic nanochannels possess a net charge, which enhances the retention of charged solutes and salt ions. Due to the presence of zwitterionic groups, these membranes are highly resistant to fouling. High chlorine resistance is achieved using a novel polymer chemistry, with no change in performance after exposure to 32,000 ppm / hour of chlorine.

[0040] Disclosed is a class of polymeric materials comprising a plurality of at least three types of repeating units:

[0041] 1. A zwitterionic repeat unit that results in the formation of a bicontinuous network of hydrophilic / water-permeable nanodomains that serve as permeation pathways for water and aqueous solutions containing solutes smaller than the domain size (preferably typically <5 nm, and preferably 0.6-3 nm, and more preferably 0.6-2 nm).

[0042] 2. A charged or ionizable repeat unit that imparts charge-based selectivity and ion retention properties via a Donnan trapping mechanism.

[0043] 3. A relatively hydrophobic repeat unit that limits swelling of the polymer in water and imparts stability to the polymer in aqueous environments. This hydrophobic repeat unit is preferably derived from a monomer whose homopolymer is insoluble in water and has a glass transition temperature above the temperature of use (e.g., above room temperature).

[0044] Polymers known as "charged zwitterionic amphiphilic copolymers" (CZACs) can be synthesized from vinyl monomers (e.g., acrylates, methacrylates, acrylamides, styrene derivatives, acrylonitrile) using well-known polymerization methods (e.g., free radical polymerization). The polymers incorporate the three types of repeating units in a roughly random / statistical order (as opposed to large blocks of individual monomers) and have a molecular weight of 20,000 to 1,000,000 g / mol (preferably 40,000 g / mol, or 100,000 to 1,000,000 g / mol). Preferably, the copolymers are linear.

[0045] In certain compositions suitable for the applications / embodiments described below for the membrane selective layer, the CZAC comprises about 30-80 wt% hydrophobic monomer, 1-40 wt% charged monomer, and 1-40 wt% zwitterionic monomer. A wider range of compositions can be used for other applications.

[0046] Exemplary monomers used to form each type of repeating unit are listed below.

[0047] Zwitterions: sulfobetaine methacrylate (SBMA)*; methacryloxyphosphorylcholine (MPC); carboxybetaine methacrylate (CBMA); sulfobetaine-2-vinylpyridine; sulfobetaine-4-vinylpyridine; sulfobetaine-vinylimidazole; and several others containing sulfobetaine, carboxybetaine, or phosphorylcholine moieties.

[0048] Charged / ionizable: methacrylic acid (MAA)*; acrylic acid; styrene sulfonate; methacrylate, acrylate, acrylamide, or styrene derivatives containing carboxylic acid, sulfonate, amine, phosphate, or other ionizable / charged groups

[0049] Relative hydrophobicity: 2,2-trifluoroethyl methacrylate (TFEMA)*; other fluorinated acrylates, methacrylates, and acrylamides (e.g., pentafluoropropyl methacrylate, heptafluorobutyl methacrylate, pentafluorophenyl methacrylate); styrene; methyl methacrylate; acrylonitrile; other monomers meeting the above criteria.

[0050] The use of polymeric materials is discussed below, particularly in the context of their use as membrane selective layers. However, they may be useful for other applications (eg, as additives, compatibilizers in membrane fabrication).

[0051] CZAC can be coated onto a porous support by methods known in the membrane industry (e.g., blade coating, non-solvent induced phase separation (NIPS), spray coating). This produces a thin film composite (TFC) membrane comprising at least two layers: a porous support with macropores, thereby providing mechanical integrity; and a thin layer of CZAC (preferably <10 μm thick, more preferably <3 μm or <1 μm thick), which acts as the "selective layer" of the membrane. In this embodiment, the CZAC layer typically contains a continuous, dense layer of CZAC (i.e., not regular "through pores," thereby providing pathways for water permeation, except for incidental defects that may arise during processing, even if these are undesirable); in other words, water should permeate through the CZAC as the primary transport mechanism, rather than through the pores / holes therein.

[0052] The resulting membranes exhibit size-based separation of neutral organic molecules, but have a higher rejection of charged solutes than neutral solutes. This quality is useful for several applications where size-based separation is insufficient. For example, if complete or partial removal of contaminants is desired, the combination of size-based and charge-based rejection provided by these membranes can produce better effluent quality. Alternatively, these membranes can separate two organic solutes (e.g., amino acids, pharmaceutical compounds) from each other that differ in the presence of charged groups.

[0053] Current membranes can be modified and adapted to increase salt rejection to address reverse osmosis (RO) / desalination processes and engineered osmotic pressure (EO), or to obtain slightly larger pore sizes to enable charge-selective, strictly ultrafiltration (UF) membranes.

[0054] Commercial NF and RO / EO membranes almost universally feature a cross-linked polyamide selective layer. These membranes present two major issues: First, they are prone to scaling, requiring several pretreatment steps that impact the cost and energy efficiency of the overall desalination process. Second, the membranes are highly sensitive to chlorine, which reacts with the selective layer. Chlorination is commonly used to kill microorganisms in the incoming water of desalination facilities to prevent biofouling. Due to the chlorine sensitivity of commercial NF and RO membranes, water is dechlorinated before being fed to the NF or RO unit and then chlorinated again before being delivered to the customer.

[0055] The current membrane addresses both of these issues: the zwitterionic groups are known and proven to be highly resistant to fouling. The membrane exhibits exceptional resistance to fouling from organic streams. Furthermore, the constituent polymers themselves are not susceptible to attack by chlorine. The membrane has been shown to be stable against commercial chlorine bleach.

[0056] When subjected to high pH buffer, the membrane can undergo pore rearrangement. When exposed to high pH buffer solution, membranes with some CZAC selective layers exhibit a one-time, irreversible, and stable increase in permeability accompanied by a slight increase in pore size.

[0057] -CZAC from the hydrophobic monomer TFEMA, the zwitterionic monomer SBMA, and the ionizable monomer MAA can be synthesized via free radical polymerization with various monomer ratios.

[0058] - This copolymer self-assembles to create a network of hydrophilic nanodomains that act as water permeation pathways.

[0059] - The membrane can be coated as a porous support onto commercial macroporous membranes to form thin film composite (TFC) membranes.

[0060] - The membranes exhibit permeabilities (defined as flux / applied pressure difference) comparable to commercial RO and NF membranes. This can be further improved by reducing the coating thickness and changing the polymer formulation.

[0061] The membrane exhibits size-based selectivity for uncharged organic molecules, including vitamin B12 and β-cyclodextrin, with a rejection of approximately 92%. The rejection model results in an estimated effective pore size of approximately 2 nm. This pore size can be tuned to lower and higher values (1-5 nm appears to be an accessible range) through polymer chemistry and other methods.

[0062] - The membrane has a significantly higher rejection of charged solutes compared to uncharged solutes of similar size.

[0063] - The membranes exhibited significant salt rejection, including approximately 95% rejection of NaSO4, comparable to some NF membranes.

[0064] - The polymer is stable when exposed to chlorine bleach (eg at pH 4).

[0065] - The membrane is highly resistant to fouling by oil emulsions.

[0066] Upon exposure to a buffer with a relatively high pH, the membrane exhibited a one-time increase in flux, accompanied by a slight decrease in retention. The new flux and pore size were stable; the changes were irreversible. Furthermore, the membrane achieved switchable flux in solutions with different ions, which could be controlled by the cations present in the solution.

[0067] In one aspect, provided herein are copolymers comprising a plurality of zwitterionic monomeric units, a plurality of charged / ionizable monomeric units, and a plurality of hydrophobic monomeric units.

[0068] In some embodiments, the molecular weight of the copolymer is 20,000 g / mol to 1,000,000 g / mol. In some embodiments, the molecular weight of the copolymer is 40,000 g / mol to 1,000,000 g / mol. In some embodiments, the molecular weight of the copolymer is 100,000 g / mol to 1,000,000 g / mol.

[0069] In some embodiments, zwitterionic monomer units comprise 1-40 wt% of the copolymer. In some embodiments, charged / ionizable monomer units comprise 1-40 wt% of the copolymer. In some embodiments, hydrophobic monomer units comprise 30-80 wt% of the copolymer.

[0070] In some embodiments, each zwitterionic monomer unit is formed from a monomer comprising a sulfobetaine, carboxybetaine, or phosphorylcholine moiety. In some embodiments, each zwitterionic monomer unit is formed from a monomer selected from the group consisting of sulfobetaine methacrylate (SBMA), methacryloxyphosphorylcholine (MPC), carboxybetaine methacrylate (CBMA), sulfobetaine-2-vinylpyridine, sulfobetaine-4-vinylpyridine, and sulfobetaine-vinylimidazole. In some embodiments, each zwitterionic monomer unit is formed from sulfobetaine methacrylate (SBMA).

[0071] In some embodiments, each charged / ionizable monomer unit is formed from a monomer selected from the group consisting of: a methacrylate, acrylate, acrylamide, or styrene derivative comprising a carboxylic acid, sulfonate, phosphate, or amine moiety. In some embodiments, each charged / ionizable monomer unit is formed from a monomer selected from the group consisting of: methacrylic acid (MAA), acrylic acid, 2-carboxyethyl acrylate, 2-carboxyethyl methacrylate, styrene sulfonate, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-(dimethylamino)ethyl methacrylate, 2-(diethylamino)ethyl methacrylate, 2-aminoethyl methacrylate, [2-(methacryloyl)ethyl methacrylate] In some embodiments, each charged / ionizable monomer unit is formed from methacrylic acid (MAA).

[0072] In some embodiments, each hydrophobic monomer unit is formed by a monomer selected from the group consisting of styrene, methyl methacrylate, acrylonitrile, fluoroalkyl acrylate, fluoroaryl acrylate, fluoroalkyl methacrylate, fluoroaryl methacrylate, fluoroalkyl acrylamide and fluoroaryl acrylamide. In some embodiments, each hydrophobic monomer unit is formed by a monomer selected from the group consisting of fluoroalkyl acrylate, fluoroaryl acrylate, fluoroalkyl methacrylate, fluoroaryl methacrylate, fluoroalkyl acrylamide and fluoroaryl acrylamide. In some embodiments, each hydrophobic monomer unit is formed by a monomer selected from the group consisting of 2,2-trifluoroethyl methacrylate (TFEMA), pentafluoropropyl methacrylate, heptafluorobutyl methacrylate and pentafluorophenyl methacrylate. In some embodiments, each hydrophobic monomer unit is formed by 2,2-trifluoroethyl methacrylate (TFEMA).

[0073] In some embodiments, the hydrophobic monomeric unit is characterized in that a homopolymer formed therefrom has a glass transition temperature above room temperature.

[0074] In some embodiments, the copolymer is a random copolymer.

[0075] In some embodiments, the copolymer is a statistical copolymer.

[0076] In some embodiments, the copolymer is a linear copolymer.

[0077] In some embodiments, the copolymer is poly((sulfobetaine methacrylate)-ran-(methacrylic acid)-ran-(2,2-trifluoroethyl methacrylate)).

[0078] In another aspect, provided herein are polymeric materials comprising a plurality of copolymers. In some embodiments, the polymeric material is in the form of a film.

[0079] In yet another aspect, provided herein is a thin film composite membrane comprising a porous support and a thin film of a polymeric material, wherein the porous support has a pore size larger than the pore size of the thin film of the polymeric material.

[0080] In some embodiments, the thin film of polymeric material has a thickness of 1 nm to 10 μm. In some embodiments, the thin film of polymeric material has a thickness of 1 nm to 3 μm. In some embodiments, the thin film of polymeric material has a thickness of 1 nm to 1 μm.

[0081] In some embodiments, the thin film of polymeric material has an effective pore size of 0.1-5 nm. In some embodiments, the thin film of polymeric material has an effective pore size of 0.6-3 nm. In some embodiments, the thin film of polymeric material has an effective pore size of 0.6-2 nm.

[0082] In some embodiments, the thin film composite membrane exhibits resistance to fouling by oil emulsions.

[0083] In some embodiments, the thin film composite membrane is stable when exposed to chlorine bleach (eg, at pH 4).

[0084] In some embodiments, the thin film composite membrane undergoes a one-time, irreversible change in pore size when exposed to a buffer having a high pH.

[0085] In some embodiments, the thin film composite membrane exhibits size-based selectivity between uncharged organic molecules.

[0086] In some embodiments, the thin film composite membrane retains charged solutes and salts.

[0087] In another aspect, provided herein are methods of size-based selection or exclusion comprising contacting a solution comprising a plurality of uncharged organic molecules of different sizes with a thin film composite membrane disclosed herein.

[0088] In yet another aspect, provided herein are methods of charge-based selection or exclusion comprising contacting a solution comprising a plurality of salts with a thin film composite membrane disclosed herein.

[0089] Example

[0090] In order to more fully understand the invention described herein, the following examples are listed.The examples described in this application are provided to illustrate the compounds, compositions, materials, devices and methods provided herein and are not to be construed in any way as limiting their scope.

[0091] Example 1 Synthesis of Poly(trifluoroethyl methacrylate)-random-poly(sulfobetaine methacrylate)-random-poly(methacrylic acid) (PTFEMA-SBMA-MAA)

[0092] Example 1A: Synthesis of PTFEMA-SBMA-MAA-B1

[0093] In this example, a random / statistical terpolymer of the monomers trifluoroethyl methacrylate (TFEMA), sulfobetaine methacrylate (SBMA), and methacrylic acid (MAA) (the terpolymers composed of these three components will be collectively referred to as PTFEMA-SBMA-MAA) was synthesized as follows. First, TFEMA and MAA were purified using a basic alumina column. DMSO (80 mL), purified TFEMA (5.49 g), SBMA (2.61 g), purified MAA (1.11 g), LiCl (0.090 g), and AIBN (11 mg) were then added to a 250 mL flat-bottomed reaction flask, which was then sealed with a rubber septum. The mixture was then stirred at room temperature for two days to dissolve the zwitterionic monomers. Afterwards, the flask was sealed with a rubber septum, purged with N2 for 40 minutes, and then immersed in a 70°C oil bath with stirring. After 20 hours, the reaction was terminated by exposure to air and the addition of MEHQ (0.5 g). For precipitation, the viscous polymer solution was then poured into 800 mL of a mixture of ethanol and hexane (1:1 volume ratio). The polymer was then cut into small pieces and washed by stirring in 800 mL of a mixture of ethanol and hexane (1:1 volume ratio) for more than 12 hours. This washing cycle was repeated 2 times. Thereafter, the polymer was dried under a hood for about 1 week and finally dried in a vacuum oven at 50°C for more than 24 hours. The yield was calculated to be 38% as determined by the weight of the dried polymer. This polymer will be referred to as PTFEMA-SBMA-MAA-B1. By integrating the following three groups of peaks, 1 H-NMR spectrum ( Figure 2 ) Calculate the composition of the purified polymer: (1) c", (2) e', (3) c, c'. The composition was calculated to be 61.9 wt% TFEMA, 31.7 wt% SBMA and 6.4 wt% MAA.

[0094] Example 1B: Synthesis of PTFEMA-SBMA-MAA-B2

[0095] In this embodiment, the random / statistical terpolymer of TFEMA, SBMA and MAA is synthesized as follows. First, SBMA (2.80 g) and DMSO (87 mL) are added to a 250 mL flat-bottomed reaction flask. The temperature is raised to 70 ° C to dissolve the zwitterionic monomer and then returned to room temperature. During this cooling period, TFEMA and MAA are both purified using a basic alumina column (VWR). After this, purified TFEMA (4.49 mL), purified MAA (1.86 mL), LiCl (0.10 g) and AIBN (9.8 mg) are added to the reaction flask. Afterwards, the flask is sealed with a rubber septum, purged with N2 for 30 minutes, and then immersed in a 70 ° C oil bath under stirring. After 20 hours, the reaction is terminated by being exposed to air and adding MEHQ (0.7 g) dissolved in approximately 5 mL DMSO. For precipitation, the viscous polymer solution is then poured into a 900 mL mixture of ethanol and hexane (1: 1 volume ratio). The polymer was then cut into small pieces and stirred by washing in 900 mL of a mixture of ethanol and hexane (1:1 volume ratio) for 12 hours. This washing cycle was repeated 3 times. Afterwards, the polymer was dried under a hood for about 1 week and finally dried in a vacuum oven at 50°C for 4 days. The yield was calculated to be 60%, as determined by the weight of the dried polymer. This polymer will be referred to as PTFEMA-SBMA-MAA-B2. By integrating the following three groups of peaks, 1 H-NMR spectrum ( Figure 3 ) Calculate the composition of the purified polymer: (1) c", (2) e', (3) c, c'. The composition was calculated to be 52.2 wt% TFEMA, 34.9 wt% SBMA and 12.9 wt% MAA.

[0096] Example 2 Polymer structure

[0097] from Figure 16 The data in the terpolymers indicate that the monomer sequence is nearly random. The terpolymer composition is similar to the initial reaction conditions, and the yield is approximately 70%. This is in contrast to the block structure typically associated with self-assembling copolymers. There are strict kinetic requirements for truly random terpolymers (all six reactivity ratios equal to 1), and therefore the terpolymers may be somewhat hierarchical and / or blocky. However, in the art, the term "random" is not strictly used. In order to best convey the polymer structure to a broad audience, the terpolymers are therefore referred to as random.

[0098] Example 3 Formation of a thin film composite (TFC) membrane with a PTFEMA-SBMA-MAA terpolymer selective layer

[0099] Example 3A. Formation of TFC membrane from PTFEMA-SBMA-MAA-B1

[0100] In this example, a TFC membrane was prepared using the polymer described in Example 1A. The copolymer was first dissolved in trifluoroethanol (TFE) at 0.11 g copolymer / mL TFE. The solution was then filtered using a 1 μm glass syringe filter, degassed by heating to 50°C for 1 hour, and allowed to cool back to room temperature. Next, a Gardco wire rod (wire diameter 2 1 The copolymer solution was coated onto a PES ultrafiltration support membrane (Trisep UE50) at a concentration of 100 μm (1 / 2, which deposited a 6 μm wet film). After coating, the coated membrane was quickly immersed in a non-solvent bath of isopropyl alcohol (IPA) for 20 minutes, followed by immersion in DI water. This procedure produced a TFC membrane whose selective layer was the PTFEMA-SBMA-MAA-B1 terpolymer described in Example 1A.

[0101] Example 3B. Formation of TFC membrane from PTFEMA-SBMA-MAA-B2

[0102] In this embodiment, the polymer preparation membrane described in Example 1B is used. Copolymer is first dissolved in trifluoroethanol (TFE) with 0.11g copolymer / mL TFE. The solution is then filtered using a 1.2μm glass syringe filter, degassed by heating to 50°C for 1 hour, and allowed to cool back to room temperature. Next, the copolymer solution is applied to a PES ultrafiltration support membrane (Trisep UE50) using a Gardco universal scraper coater with a 20μm gate setting. After coating, the polymer solution film is evaporated for 15 seconds. The coated membrane is then immersed in a non-solvent bath of isopropyl alcohol (IPA) for 20 minutes, then immersed in DI water. This procedure produces a thin film composite (TFC) membrane whose selective layer is the PTFEMA-SBMA-MAA-B2 terpolymer described in Example 1B.

[0103] Cross-sections of the TFC membranes described in Examples 2A and 2B were observed using a scanning electron microscope (SEM), which allowed analysis of the selective layer thickness and membrane morphology. To prepare the samples, membrane sections were freeze-fractured and sputter-coated with gold-palladium. SEM images of the membrane cross-sections were obtained using a Phenom G2 pure benchtop SEM at a 5 kV setting. Figure 4A 、 Figure 4B and Figure 4C Shown are SEM images of an uncoated Trisep UE50 membrane (support), a TFC membrane from Example 2A, and a TFC membrane from Example 2B. For each of the two examples, the selective layer was observed to be dense and 0.5-1 μm thick.

[0104] Example 4 Water permeability of PTFEMA-SBMA-MAA TFC membrane

[0105] In this example, the pure water permeability of the membranes described in Examples 2A and 2B was measured and compared to membranes prepared from PTFEMA-SBMA.

[0106] For the experiments, a 10 mL Amicon 8010 stirred cell in dead-end mode was used. The membrane sample area was 4.1 cm 2 The membrane was stirred at 500 RPM and the pressure was 30 psi for the PTFEMA-SBMA-MAA-B1 membrane and 50 psi for the PTFEMA-SBMA-MA A-B2 membrane. To measure the membrane permeability, an Ohaus Scout Pro balance connected to a computer was used. The simultaneous measurement of the permeate mass over time allowed the membrane flow rate to be measured, which allowed the membrane permeability to be calculated. The permeabilities of the PTFEMA-SBMA-MAA-B1 membrane and the PTFEMA-SBMA-MAA-B2 membrane were 1.7 L / m 2 .h.bar (abbreviated as LMH / bar) and 2.5LMH / bar (Table 1).

[0107] Table 1: Water permeability and composition of PTFEMA-SBMA-MAA-B1 and PTFEMA-SBMA-MAA-B2 membranes described in Examples 3A and 3B

[0108]

[0109] Example 5 Neutral solute rejection of PTFEM-SBMA-MAA TFC membrane

[0110] In this example, various neutral solutes were filtered using the membrane described in Example 3B. The objectives of these experiments were: (1) to demonstrate the ability of the membrane described in Example 3B to filter small neutral molecules from solution, and (2) to establish the effective pore size for the membrane described in Example 3B.

[0111] Filtration experiments were performed using a 10 mL Amicon 8010 stirred cell in dead-end mode. For all experiments, the membrane sample area was 4.1 cm 2 The mixture was stirred at 500 RPM and the pressure was 50 psi. The first 1.5 mL of the permeate was discarded and the subsequent 0.7 mL was collected for measurement of the permeate concentration. The permeate concentration was measured using the chemical oxygen demand (COD) of sugars and UV-vis spectroscopy of the dye.

[0112] Figure 5BThe retention of neutral sugars and neutral dye molecules is shown. Size selectivity was observed for the neutral solutes tested, with retention rates of approximately 92% for vitamin B12 (1.48 nm hydrated diameter) and beta-cyclodextrin (1.54 nm hydrated diameter) (Table 2). By fitting the retention data for sugar molecules to the Extended Nernst Planck Equation with steric boundary conditions, the effective pore size was calculated to be 1.95 nm.

[0113] Table 2. Solute type, hydrated diameter, and retention of various neutral solutes filtered through the PTFEMA-SBMA-MAA-B2 TFC membrane.

[0114] solute Solute type Hydration diameter (nm) Retention rate (%) glucose sugar 0.725 18.1 maltose sugar 0.94 52.1 α-cyclodextrin sugar 1.34 83.8 β-cyclodextrin sugar 1.54 91.4 Vitamin B12 dye 1.48 93.3 Riboflavin dye 1.16 40.8 Rutin dye 1.32 62.4

[0115] Example 6 Salt rejection of PTFEMA-SBMA-MAA TFC membrane

[0116] In this example, various ionic solutes were filtered using the TFC membranes described in Example 3B. The objectives of these experiments were: (1) to demonstrate the ability of the membranes prepared as described in Example 3B to filter salts from solution, and (2) to demonstrate the ability of the membranes prepared as described in Example 3B to selectively filter ionic species while passing neutral solutes of the same size.

[0117] Filtration experiments were performed using a 10 mL Amicon 8010 stirred cell in dead-end mode. For all experiments, the membrane sample area was 4.1 cm 2 , stirring speed was 500 RPM, and pressure was 50 psi. The first 1.5 mL of permeate was discarded, and the subsequent 0.7 mL was collected for permeate concentration measurement. The permeate concentration was measured using a conductivity meter. The data are listed in Table 3.

[0118] Figure 6A The PTFEMA-SBMA-MAA-B1 and PTFEMA-SBMA-MAA-B2 membranes demonstrated greater rejection of charged solutes compared to the PTFEMA-SBMA membrane. Since all three membranes exhibited similar rejection of neutral solutes, this finding demonstrates that MAA imparts anion selectivity to the CZAC membrane. The highest rejection was for Na₂SO₄, ranging from 93% to 95%. Rejection for CaSO₄ ranged from 40% to 70%, and for NaCl from 30% to 60%.

[0119] To test the hypothesis that deprotonated MAA imparts charge selectivity to the membrane, Na2SO4 ( Figure 6BIf deprotonated MAA is the source of anion selectivity, then selectivity should disappear under acidic conditions. As expected, R(Na2SO4) was observed to decrease with decreasing pH, which can be explained by a shift in equilibrium from deprotonated MAA to protonated MAA. The loss of selectivity only truly begins below pH 5.0, indicating that the effective pKa of the MAA in the system is less than about 4.0 (using the Donnan space pore model combined with the Henderson Hasselbach equation, the pKa was fit to 3.72; see Supporting Information).

[0120] The effective pKa < 4.0 is much lower than the pKa of 4.78 reported for MAA monomer. This means that MAA is approximately 10 times more reactive when incorporated into CZAC nanostructures than when in free solution. This contradicts expectations, as confinement is typically found to reduce MAA reactivity.

[0121] Figure 6C shows the retention of charged solutes. First, Figure 6C The following two notable performance characteristics of the PTFEMA-SBMA-MAA-B2 membrane are shown: (1) 96% rejection of 1 mM (142 ppm) Na2SO4 and 1 mM (110 ppm) Li2SO4 solutions; and (2) 93% rejection of 5 mM (710 ppm) Na2SO4 and 5 mM (550 ppm) Li2SO4 solutions (Table 3). The rejection of CaSO4 and MgSO4 ranged from 40% to 70%, and the rejection of NaCl and LiCl ranged from 30% to 60%. The retention of solutes decreased with increasing feed concentration, which is consistent with Donnan exclusion. The retention of different salt species can be understood by fitting the retention data to the Donnan steric pore model, which is a transport model that describes how the combination of hindered transport, steric exclusion, and Donnan equilibrium determines the retention of solutes by charged membranes. By comparing Figures 5 and Figure 6C , the ability of the membrane to filter ionic species when passing neutral solutes of the same size can be seen. Small ionic species (sulfate has a hydrated diameter of 0.46 nm; all ions used in the study have hydrodynamic diameters less than 0.7 nm) are retained by the membrane, while neutral solutes with hydrated diameters less than 1.0-1.5 nm are only minimally retained. Table 3. Concentration and Retention of Various Salts by the PTFEMA-SBMA-MAA-B2 Membrane Described in Example 3B

[0122]

[0123] Example 7 Compared with PTFEMA-r-SBMA TFC membrane, the rejection rate of dye and Na2SO4 by PTFEMA-SBM A-MAA TFC membrane is

[0124] In this example, the rejection of dye and Na2SO4 by the TFC membrane prepared in Example 3A was determined and compared to the rejection of a PTFEMA-r-SBMA TFC membrane (referred to as PTFEMA-SBMA). The synthesis of PTFEMA-SBMA and the fabrication of PTFEMA-SBMA TFC membranes can be found elsewhere. It is noted here that the main difference between PTFEMA-SBMA membranes and PTFEMA-SBMA-MAA membranes is that the PTFEMA-SBMA membranes lack MAA and, therefore, have a lower rejection rate for charged solutes. The objectives of these experiments were: (1) to demonstrate the ability of the PTFEMA-SBMA-MAA-B1 membrane to filter dye from solution, a feature that would be useful in applications such as dye removal in the textile industry; and (2) to further demonstrate the charge selectivity observed with the PTFEMA-SBMA-MAA TFC membrane, with the PTFEMA-SBMA TFC membrane serving as an appropriate control.

[0125] Filtration experiments were performed using a 10 mL Amicon 8010 stirred cell in dead-end mode. For all experiments, the membrane sample area was 4.1 cm 2 , stirring speed 500RPM, and pressure 27psi. The first 1.8mL of permeate was discarded, and the next 0.7mL was collected to measure the concentration of the permeate. The permeate concentration was measured for the dye using a UV-visible spectrophotometer, and the conductivity was measured for Na2SO4. Assuming that the dye molecule is a volume of V 摩尔 sphere, and the diameter of the dye molecule is obtained, where V 摩尔 is the molar volume of the dye molecule; the molar volume of the dye was obtained using the Molecular Modeling Pro software of ChemSW.

[0126] Figure 7A and Figure 7BThe retention rates of various dyes and Na2SO4 are shown. Table 4 lists the abbreviations, calculated diameters, charges, and retention rates of the solutes by the PTFEMA-SBMA-MAA-B1 membrane and the PTFEMA-SBMA membrane. The neutral dye retention rates of the PTFEMA-SBMA-MAA-B1 membrane and the PTFE MA-SBMA membrane are similar, indicating that the effective pore sizes are similar. In contrast, the retention rate of the PTFEMA-SBMA-MAA-B1 membrane for anionic solutes is greater than that of the PTFE MA-SBMA membrane. This provides evidence that membranes made from CZAC achieve better rejection of charged solutes than membranes made from copolymers of zwitterionic monomers and hydrophobic monomers alone. In addition, the rejection of charged solutes can be explained by the presence of MAA in the PTFEMA-SBMA-MAA-B1 copolymer: MAA (a weak acid) is negatively charged when deprotonated in aqueous solution. If MAA is incorporated into the zwitterionic domains of the self-assembled PTFEMA-SBMA-MAA-B1 selective layer, it can impart a negative charge to the membrane's nanochannels. This results in enhanced retention of ionic species, despite the well-documented phenomenon known as Donnan exclusion.

[0127] Table 4. Solute abbreviations, calculated diameters, charges, and solute rejections for the TFC membranes and PTFEMA-r-SBMATFC membranes described in Example 2A.

[0128]

[0129] Example 8 Antifouling properties of PTFEMA-SBMA-MAA TFC membrane

[0130] Zwitterions are among the most resistant materials known to date. This is because the surface adsorption events of pollutants that constitute pollution are limited by the strong hydration shell surrounding the zwitterions (according to simulations, ΔG 水合 (Approximately 500 kJ / mol). Previous work has shown that membranes composed of random zwitterionic copolymers are highly resistant to fouling, demonstrating that zwitterions can still act as antifouling agents within the confines of the membrane nanostructure. To test whether this principle extends to CZAC membranes, dead-end filtration was performed using different model foulants. A commercial NF membrane was used as a benchmark. The membrane was fouled for 24 hours, and the initial flux of the CZAC membrane matched that of the benchmark.

[0131] In this example, the fouling resistance of the PTFEMA-SBMA-MAA-B2 membrane described in Example 3B was measured using an oil-in-water emulsion. The purpose was to demonstrate that the membrane was fouling resistant, a crucial characteristic for any membrane competing with easily fouling feedstocks.

[0132] Fouling experiments were performed using a 10 mL Amicon 8010 stirred cell in dead-end mode. For all experiments, the membrane sample area was 4.1 cm 2 The membrane permeability is measured by a flow cytometer. ... Figure 8A and Figure 8B The two fouling experiments performed above are shown. All of these reveal that the PTFEMA-SBMA-MAA-B2 membrane has anti-fouling properties.

[0133] Figure 8C The antifouling property of PTFEMA-SBMA-MAA-B1 against BSA / CaCl2 (1000ppm and 10mM respectively) is shown, wherein NP30 (Microdyne; PES) serves as a control. BSA is a common model protein contaminant, and calcium salt is added to increase its adsorption tendency. Throughout the 24-hour contamination experiment, it was found that PTFEMA-SBMA-MAA-B1 contamination was significantly lower than NP30. After a short rinse of the membrane, the flux of PTFEMA-SBMA-MAA-B1 was fully recovered, which proves that the adsorption event is reversible. In contrast, NP30 was irreversibly contaminated.

[0134] Figure 8D The antifouling properties of PTFEMA-SBMA-MAA-B2 against humic acid / alginate (1000 ppm each) are shown, with UA60 (Trisep; PA) serving as a control. The pH was lowered to 4.5 with HCl to increase adsorption. Throughout the 24-hour fouling experiment, PTFEMA-SBMA-MAA-B2 fouled less than UA60. After a brief rinse, PTFEMA-SBMA-MAA-B1 recovered 93% of its initial flux, and permeability rebounded to 96% of its initial value after 5 hours. UA60 experienced a greater initial decline (82% recovery immediately after rinsing), ultimately reaching 93% after 13 hours.

[0135] Example 9 Chlorine resistance of PTFEMA-SBMA-MAA-B1 TFC membrane

[0136] In this example, the PTFEMA-SBMA-MAA-B1 membrane was exposed to a solution containing a chlorinated solution prepared by diluting commercial Clorox bleach and adjusting its pH to an acidic value consistent with commercial cleaning procedures. The purpose of this was to demonstrate the chlorine resistance of the PTFEMA-SBMA-MAA-B1 membrane, which would enable the membrane to be cleaned with sodium hypochlorite, a common disinfectant. Polyamide membranes, which represent the cornerstone of the NF market, are unstable when exposed to chlorine, a major drawback of the technology.

[0137] For the experiments, a 10 mL Amicon 8010 stirred cell in dead-end mode was used. The membrane sample area was 4.1 cm 2 , stirring speed was 500RPM, and pressure was 50psi. To measure membrane permeability, an Ohaus Scout Pro balance connected to a computer was used. The synchronous measurement of permeate mass over time allowed the measurement of membrane flow rate, which allowed the calculation of membrane permeability. The deionized water permeability of the membrane was measured as described above. Chlorinated solution was prepared by diluting commercial Clorox laundry bleach with deionized water and adjusting its pH to 4 to ensure that the vast majority of hypochlorite was hypochlorous acid. The final HClO concentration was estimated to be approximately 15,000mg / L. The membrane samples were exposed to this solution for 1-2 hours. Then, the permeability was measured again.

[0138] Figure 9 It was revealed that the permeability of the membrane remained unchanged after treatment with the chlorinated solution, thereby indicating that the membrane remained stable when exposed to chlorine. Figure 10 Showing the effect of chlorine treatment on the bond chemistry of PTFEMA-SBMA-MAA-B2. FTIR spectra taken before and after immersion in a 2,000 ppm sodium hypochlorite solution at pH 4.5 for 16 hours show that the structure remains intact before and after exposure.

[0139] Table 5. Effect of chlorine treatment on the permeability and selectivity of CZAC-2 (PTFEMA-SBMA-MAA-B2). Membrane performance data collected before and after immersion in 2,000 ppm NaClO solution (pH 4.5) for 16 hours.

[0140]

[0141] Example 10 Base rearrangement was observed in PTFEMA-r-SBMA-r-MAA TFC membrane

[0142] In this example, the irreversible reaction of PTFEMA-SBMA-MAA-B1 membrane to alkali (called base rearrangement) was studied. The purpose of this is to reveal the unique response behavior of membranes derived from this new material. Filtration experiments were performed using a 10 mL Amicon 8010 stirred cell in dead-end mode. For all experiments, the membrane sample area was 4.1 cm 2 , stirring speed was 500 RPM, and pressure was in the range of 30-50 psi.

[0143] Figure 11 The base rearrangement of the PTFEMA-SBMA-MAA-B1 membrane to an alkaline buffer system (PBS, pH = 7.4) is shown. After initial exposure to a 10 mM PBS solution, the permeability increased from an initial value of approximately 1.8 LMH / bar to approximately 2.8 LMH / bar. After contacting the membrane with DIW, the permeability increased to approximately 5.1 LMH / bar in distilled water (DIW). Following the base rearrangement, the permeability could be reversibly and rapidly switched between 5.1 LMH / bar in DIW and 2.8 LMH / bar in PBS. There is evidence that TFC membranes with a selective layer composed solely of hydrophobic and zwitterionic monomers do not exhibit this response to PBS. 4

[0144] for Figure 11 The rearrangement observed in the 2- The driving force is the deprotonation of the acidic MAA protons by the strongest base in PBS. To verify this hypothesis, the following experiments were performed. First, the vitamin B12 retention rate, Na2SO4 retention rate, and permeability of the original PTFEMA-SBMA-MAA-B1 membrane were determined. Then, NaOH was filtered through the membrane. (aq) (pH 11, 0.1 mM), during which time the permeability was measured. The membrane was then switched back to DIW to see if the same irreversible reaction occurred. Afterwards, the vitamin B12 retention and Na2SO4 retention were measured again. Figure 12A and Figure 12B The results of this experiment are shown and reveal that NaOH (aq) It is indeed possible to induce the base rearrangement observed in the case of PBS. It is also noted that no rearrangement is observed using the PTFE MA-SBMA membrane. Figure 13 Evidence of exposure to NaOH (aq) After addition, the retention rates of vitamin B12 and Na2SO4 decreased, but it was noted that the retention rate of vitamin B12 decreased more than that of Na2SO4.

[0145] The permeability of the membranes was consistently measured using a simple mass balance during the filtration experiments of Example 2A and Example 2B. Results of the filtration experiments (which captured 17 different uncharged / charged / dye solutes, such as Figure 14 As shown (see Table 6 for a list of filter IDs). The membrane flux was not affected during and after filtration with these solutes. This further indicates that interaction with the base is the root cause of the PTFEMA-SBMA-MAA membrane rearrangement.

[0146] Table 6. List of filter IDs

[0147]

[0148]

[0149] We also explored how the base-rearranged PTFEMA-SBMA-MAA-B1 membrane responds to alkaline solutions containing cations other than sodium and potassium (NaOH (aq) (PBS contains sodium as a cation; PBS contains sodium and potassium as cations.) Calcium is known to bind to carboxylates, and thus the binding interaction can have an impact on membrane flux. For this experiment, the permeability of the base-rearranged PTFEMA-SBMA-MAA-B1 membrane was measured using an alkaline solution of CaSO4 (pH = 10) as feed. Figure 15 The results of this experiment are shown, which show a long recovery time for the DIW flux. This suggests that the interaction between the cations and the deprotonated MAA leads to a decrease in the permeability of the rearranged PTFEMA-SBMA-MAA membrane.

[0150] References

[0151] 1. Asatekin Alexiou, A.; Bengani, P. Zwitterion Containing Membranes. U.SApplication 61901624, 2013.

[0152] 2. Bengani, P.; Kou, Y.; Asatekin, A., Zwitterionic copolymer self-assembly for fouling resistant, high flux membranes with size-based small molecules selectivity. Journal of Membrame Science 2015, 493, 755-765.

[0153] 3.Bengani-Lutz,P.;Asatekin Alexiou,A.Fabrication of filtrationmembranes.Patent application 62 / 416,340,November 2,2016,filed 2016.

[0154] 4.Bengani-Lutz,P.;Converse,E.;Cebe,P.;Asatekin,A.,Self-AssemblingZwitterionic Copolymers as Membrane Selective Layers with Excellent FoulingResistance:Effect of Zwitterion Chemistry.ACS Applied Materials&Interfaces2017,9(24),20859-20872.

[0155] 5.Bengani-Lutz,P.;Zaf,R.D.;Culfaz-Emecen,P.Z.;Asatekin,A.,Extremelyfouling resistant zwitterionic copolymer membranes with~1nm pore size fortreating municipal,oily and textile wastewater streams.Journal of MembraneScience 2017,543(Supplement C),184-194.

[0156] 6.Sadeghi,I.;Asatekin,A.,Spontaneous Self-Assembly and Micellizationof Random Copolymers in Organic Solveints.Macromolecular Chemistry andPhysics 2017,218(20),1700226.

[0157] 7.Sadeghi,I.;Asatekin,A.,Membranes with Functionalized Nanopores forAromaticity-Based Separation of Small Molecules.ACS Applied Materials&Interfaces 2019,11(13),12854-12862.

[0158] 8.Asatekin Alexiou,A.;Sadeghi,I.Two-layer nanofiltrationmembranes.Patent application 62 / 131,001,March 10,2015,2015.

[0159] 9.Ji,Y.L.;An,Q.F.;Zhao,Q.;Sun,W.D.;Lee,K.R.;Chen,H,L.;Gao,C.J.,Novelcomposite nanofiltration membranes containing zwitterions with high permeateflux and improved anti-fouling performance.Journal of Membrane Science 2012,390,243-253.

[0160] 10.Petersen,R.J.,Composite Reverse Osmosis and NanofiltrationMembranes.Journal of Membrane Science 1993,83(1),81-150.

[0161] 11.Bengani-Lutz,P.Zwitterionic Copolymer Self-assembly for FoulingResistant,High Flux Membranes with Small Molecule Selectivity.Ph.D.Thesis,Tufts University,2017.

Claims

1. A thin film composite membrane comprising a porous support and a thin film of a polymer material; wherein: The pore size of the porous support is larger than the pore size of the thin film of the polymer material; and The polymer material comprises a copolymer comprising a plurality of zwitterionic monomer units, a plurality of charged / ionizable monomer units and a plurality of hydrophobic monomer units; further wherein: The copolymer is a linear, statistical and random copolymer; and Each of the hydrophobic monomer units is formed from a monomer selected from the group consisting of styrene, methyl methacrylate, acrylonitrile, fluoroalkyl acrylate, fluoroaryl acrylate, fluoroalkyl methacrylate, fluoroaryl methacrylate, fluoroalkyl acrylamide, and fluoroaryl acrylamide. 2 . The thin film composite membrane of claim 1 , wherein the molecular weight of the copolymer is 20,000 g / mol to 1,000,000 g / mol. 3 . The thin film composite membrane of claim 1 , wherein the molecular weight of the copolymer is 40,000 g / mol to 1,000,000 g / mol. The thin film composite membrane of claim 1 , wherein the molecular weight of the copolymer is 100,000 g / mol to 1,000,000 g / mol.

5. The thin film composite membrane of any one of claims 1 to 4, wherein the zwitterionic monomer units comprise 1 to 40 wt% of the copolymer.

6. The thin film composite membrane of any one of claims 1 to 4, wherein the charged / ionizable monomer units comprise 1 to 40 wt% of the copolymer.

7. The thin film composite membrane according to any one of claims 1 to 4, wherein the hydrophobic monomer unit accounts for 30 to 80 wt% of the copolymer.

8. The thin film composite membrane of any one of claims 1 to 4, wherein each of the zwitterionic monomer units is formed from a monomer comprising a sulfobetaine, carboxybetaine, or phosphorylcholine moiety.

9. The thin film composite membrane according to any one of claims 1 to 4, wherein each of the zwitterionic monomer units is formed from a monomer selected from the group consisting of sulfobetaine methacrylate (SBMA), methacryloxyphosphorylcholine (MPC), carboxybetaine methacrylate (CBMA), sulfobetaine-2-vinylpyridine, sulfobetaine-4-vinylpyridine, and sulfobetaine-vinylimidazole.

10. The thin film composite membrane of any one of claims 1 to 4, wherein each of the zwitterionic monomer units is formed from sulfobetaine methacrylate (SBMA).

11. The thin film composite membrane of any one of claims 1 to 4, wherein each of the charged / ionizable monomer units is formed from a monomer selected from the group consisting of methacrylates, acrylates, acrylamides, or styrene derivatives containing carboxylic acid, sulfonate, phosphate, or amine moieties.

12. The thin film composite membrane according to any one of claims 1 to 4, wherein each of the charged / ionizable monomer units is formed from a monomer selected from the group consisting of methacrylic acid (MAA), acrylic acid, 2-carboxyethyl acrylate, 2-carboxyethyl methacrylate, styrene sulfonate, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-(dimethylamino)ethyl methacrylate, 2-(diethylamino)ethyl methacrylate, 2-amino acrylate, 2-(dimethylamino)ethyl acrylate, 3-(dimethylamino)propyl acrylate, N-acryloyl-L-valine, (3-acrylamidopropyl)trimethylammonium chloride, N-[3-(dimethylamino)propyl]methacrylamide, 2-isopropenylaniline, 4-[N-(methylaminoethyl)aminomethyl]styrene, and (vinylbenzyl)trimethylammonium chloride.

13. The thin film composite membrane of any one of claims 1 to 4, wherein each of the charged / ionizable monomer units is formed from methacrylic acid (MAA).

14. The thin film composite membrane of any one of claims 1 to 4, wherein each of the hydrophobic monomer units is formed from a monomer selected from the group consisting of 2,2-trifluoroethyl methacrylate (TFEMA), pentafluoropropyl methacrylate, heptafluorobutyl methacrylate, and pentafluorophenyl methacrylate.

15. The thin film composite membrane according to any one of claims 1 to 4, wherein each of the hydrophobic monomer units is formed from 2,2-trifluoroethyl methacrylate (TFEMA).

16. The thin film composite membrane of any one of claims 1 to 4, wherein the hydrophobic monomer unit is characterized in that the homopolymer formed therefrom has a glass transition temperature above room temperature.

17. The thin film composite membrane of any one of claims 1-4, wherein the copolymer is poly((sulfobetaine methacrylate)-ran-(methacrylic acid)-ran-(2,2-trifluoroethyl methacrylate)).

18. The thin film composite membrane of any one of claims 1 to 4, wherein the thin film of the polymer material has a thickness of 1 nm to 10 μm.

19. The thin film composite membrane of any one of claims 1 to 4, wherein the thin film of the polymer material has a thickness of 1 nm to 3 μm.

20. The thin film composite membrane of any one of claims 1-4, wherein the thin film of the polymer material has a thickness of 1 nm to 1 μm.

21. The thin film composite membrane of any one of claims 1-4, wherein the thin film of the polymeric material has an effective pore size of 0.1 nm to 5 nm.

22. The thin film composite membrane of any one of claims 1-4, wherein the thin film of the polymeric material has an effective pore size of 0.6 nm to 3 nm.

23. The thin film composite membrane of any one of claims 1-4, wherein the thin film of the polymeric material has an effective pore size of 0.6 nm to 2 nm.

24. The thin film composite membrane of any one of claims 1-4, wherein the thin film composite membrane retains charged solutes and salts.

25. A method of size-based selection or exclusion comprising contacting a solution comprising a plurality of uncharged organic molecules of different sizes with the thin film composite membrane of any one of claims 1-24.

26. A method of charge-based selection or exclusion comprising contacting a solution comprising a plurality of salts with the thin film composite membrane of any one of claims 1-24.

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