Development of reactivity switchable raft agents

Abstract

A composition of matter useful in a RAFT polymerization process including a RAFT agent coupled to an electron acceptor and a photo-switchable compound. Diblock copolymers synthesized using the RAFT agent.

Description

[0001] PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0002] DEVELOPMENT OF REACTIVITY SWITCHABLE RAFT AGENTS

[0003] CROSS REFERENCE TO RELATED APPLICATIONS

[0004] This application claims the benefit under 35 U. S. C Section 119(e) of co5 pending and commonly-assigned U. S. Provisional Patent Application No. 63 / 741,849 filed January 4, 2025, by Craig J. Hawker, Kazuhisa Iwaso, and Hengbin Wang, entitled “DEVELOPMENT OF REACTIVITY SWITCHABLE RAFT AGENTS,” which application is incorporated by reference herein.

[0005] 10 BACKGROUND OF THE INVENTION

[0006] 1. Field of the Invention.

[0007] The present disclosure relates to Reversible addition - fragmentation chain transfer (RAFT) agents and methods and systems for using the same.

[0008] 2. Description of the Related Art.

[0009] Reversible addition - fragmentation chain transfer (RAFT) polymerization emerges as an effective tool for obtaining block copolymers using multi component vinyl monomers and RAFT agent structures devised according to the reactivity of each of the vinyl monomers. Vinyl monomers are broadly classified into conjugated 20 monomers such as acrylate esters (more activated monomers, MAMs) and unconjugated monomers such as vinyl esters (less activated monomers, LAMs). However, block copolymerization of MAMs and LAMs is difficult due to the different reactivities of each monomer, and limited examples have been reported1,2.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0010] The reactivity of neutral RAFTs agent for LAMs and MAMs can depend on the C=S bond length on the dithiocarbamate. For example, for monomers such as VAc, where the reactivity of the radical is extremely high, it is advantageous for the C=S bond of the dithiocarbamate to be single bonded (low reactivity). This is because when the 5 C=S bond of the dithiocarbamate is close to the double bond nature, the radical adduct becomes extremely stable and subsequent cleavage is less likely to occur. In other words, the RAFT agent functions as a polymerization inhibitor. On the other hand, with monomers that produce relatively stable radicals, such as MMA, if the C=S bond is not double bond (low reactivity), addition to the RAFT agent does not occur and 10 free radical polymerization occurs.

[0011] What is needed, then, are improved methods for fabrication of copolymers using RAFT processes. The present disclosure satisfies this need.

[0012] SUMMARY OF THE INVENTION

[0013] In one illustrative example, a Reversible addition - fragmentation chain transfer (RAFT) agent with an electron acceptor connected to a dithiocarbamate via a photochromic diarylethene (DE) was developed. When the diarylethene group is at the ring-opening form, the two aromatic groups are not electrically connected. The C=S bond approaches single-bonding nature due to electron donating ability of the 20 nitrogen on dithiocarbamate, while at the ring-closing form it behaves as an electron withdrawing group due to conjugation, while the C=S bond approaches doublebonding nature. These C=S bond lengths affect the reactivity of MAMs and LAMs.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0014] The RAFT agent is novel because the controlled polymerization property of the RAFT agent can be switched reversibly by irradiating of UV and Vis light respectively. Specifically, before UV light irradiation, the polymerization properties are enhanced toward vinyl esters as dithiocarbamates, while in UV light irradiating, 5 the RAFT agent show controlled polymerization properties such as controlled chain growth, well-defined molecular weight and dispersity towards acrylates.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Referring now to the drawings in which like reference numbers represent 10 corresponding parts throughout:

[0017] Figure la. Schematic illustration of photo-chromic behavior of DE RAFT agents and their controlled polymerization of VAc (LAM) and MA (MAM).

[0018] Figure lb. GPC trace of VAc polymerization.

[0019] Figure 1c. Table 1: polymerization results of VAc with DE9o (also named as DEo).

[0020] Figure 2 a) conversion of VAc relative to reaction time, b) Mnand D of PVAc relative to conversion of VAc. Mnand D at 3% conversion are not shown due to hard in determining the polymer peak.

[0021] Figure 3. 'H NMR Spectra of controlled PVAc (DE9oPVAc) (400 MHz, 20 CDCh).

[0022] Figure 4a. GPC trace of PMA polymerization with DE9o.

[0023] Figure 4b. Table 2. Polymerization results of PMA with DE9o.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0024] Figure 5a. GPC trace of PMA polymerization with DE9c (also named as DEc).

[0025] Figure 5b. Table 3. Polymerization results of PMA with DE9c.

[0026] Figure 6. a) conversion of PMA relative to reaction time, b) Mnand D of 5 PMA relative to conversion of MA.

[0027] Figure 7,'H NMR spectra of DE9cPMA (upper) and DE9oPMA (lower) which is isomerized from DE9cPMAby visible light irradiation.

[0028] Figure 8a. GPC trace of DE9cPMAand DE9oPMA which is isomerized from DE9cPMA.

[0029] 10 Figure 8b. Table 4. GPC results of DE9cPMA and DE9oPMA.

[0030] Figure 9a. GPC trace of PDDA (poly(dodecylacrylate)) polymerization. Purple line represents the parent polymer DE9cPDDA and black line represents DE9oPDDA after photo isomerization.

[0031] Figure 9b. Table 5. GPC results of DE9cPDDA and DE9oPDDA.

[0032] Figure 10.1H NMR spectra of DE9cPDDA (upper) and DE9oPDDA (lower) which is isomerized from DE9cPDDAby visible light irradiation.

[0033] Figure Ila. GPC trace of DE9oPDDA (parent) and DE9oPDDA- / ?-PVAc. Figure 11b. Table 6. Polymerization results of diblock copolymer DE9oPDDA-b-PVAc.

[0034] 20 Figure 12. 'H NMR Spectra of DE9oPDDA-Z>-PVAc (400 MHz, CDCh).

[0035] Figure 13. Scheme 7 synthesis of DE9o.

[0036] Figure 14 shows 'H NMR spectra of 2,4-dibromo-3,5-dimethylthiophene (400PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0037] MHz CDCh).

[0038] Figure 15 shows 'HNMR spectra of BrThPy (400 MHz CDCh).

[0039] Figure 16 shows 'HNMR spectra of BocDE9o (500 MHz DMSO-d6). Figure 17 shows 'HNMR spectra of BocDE9c (500 MHz DMSO-d6). 5 Figure 18 shows 'HNMR spectra of MeNDE9o (500 MHz DMSO-tfc).

[0040] Figure 19 shows 'HNMR spectra of DE9o.

[0041] Figure 20 shows 'HNMR spectra of DE9c (500 MHz DMSO-d6).

[0042] Figure 21. GPC profile of PMA radical polymerization with the addition of BocDE9.

[0043] 10 Figure 22. Table 7. Conditions and results of PMA radical polymerization with the addition of BocDE9.

[0044] Figure 23. GPC profile of PMA polymerization using DE9o and DE9c. Figure 24 (table 8). PMA polymerization condition and results using DE9o and DE9c.

[0045] Figure 25. 'HNMR spectrum of PMA provided from RAFT polymerization using DE9c.

[0046] Figure 26. Formulas I and II.

[0047] Figure 27. Scheme 1.

[0048] Figure 28. Scheme 2.

[0049] 20 Figure 29. Scheme 4.

[0050] Figure 30. Scheme 5.

[0051] Figure 31. Scheme 6.

[0052] Figure 32. Preparation of BocDE9cPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0053] Figure 33. Preparation of MeNDE9o.

[0054] Figure 34 Preparation of DE9o.

[0055] Figure 35. Preparation of DE9c.

[0056] Figure 36. Scheme 8.

[0057] 5 Figure 37. RAFT polymerization of MAMs using a photo switchable RAFT agent. Visible light-induced photoisomerization of the RAFT agent leads to reactivity switching and subsequent RAFT polymerization of LAMs from the macro-CTA (CTA = chain transfer agent) to afford a well-defined MAM-LAM diblock copolymer. Chromatographic fractionation followed by SAXS characterization enables

[0058] 10 construction of a high-resolution phase diagram.

[0059] Figure 38. (a) Photoisomerization between DEo and DEc, and the thermodynamic equilibrium between anti-parallel DEoapand parallel DEoP. (b) Kinetics of the photoisomerization from DEo to DEc under UV irradiation (k = 302 nm). (c) Kinetics of the photoisomerization from DEc to DEo under visible light irradiation (k = 530 nm). (d) UV-Vis spectral changes during the photoisomerization from DEo to DEc under UV irradiation (k = 302 nm). (e) UV-Vis spectral changes during the photoisomerization from DEc to DEo under visible light irradiation (1 = 530 nm).

[0060] Figure 39. (a) Conversion profiles of MA polymerization (RAFT agents: DEo 20 = open circles, DEc = purple circles). DEo is faster but less controlled; DEc is slower but controlled, (b) Mnand D during MA polymerization. DEo shows deviation from theoretical Mnand broadening; DEc shows linear Mngrowth and decreasing D characteristic of controlled polymerization, (c) Conversion profiles of VAcPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0061] polymerization (RAFT agent: DEo). After an induction (~8 h), conversion reached 78% at 45 h, while DEc showed inhibition for the polymerization, (d) Mnand D during VAc polymerization. DEo gave Mnclose to theoretical values with low D.

[0062] Figure 40. (a) Schematic illustration of the photoisomerization of DEoPDDA 5 to DEcPDDA under visible-light irradiation, followed by RAFT polymerization of vinyl acetate (LAMs) to yield PDDA-Z>-PVAc block copolymers, (b) UV-Vis absorption spectra of 0.01 mM hexane solution of DEcPDDA (purple dashed line) and DEoPDDA (black line), (c) Photograph of a hexane solution of DEcPDDA. (d) Photograph of a hexane solution of DEoPDDA. (e) GPC traces of DEcPDDA (purple 10 dashed line) and DEoPDDA (black line), (f) GPC traces of DEoPDDA (black dashed line) and PDDA-Z>-PVAc (red line).

[0063] Figure 40. (g) Representative SAXS example of each morphology. Peak positions are highlighted by black bars, (h) Variable-temperature SAXS on a library of 25 well-ordered diblock copolymers derived from the synthesis and separation of only 1 parent copolymer sample was used to construct the phase diagram. Color indicates the morphology as determined by manual analysis of SAXS data.

[0064] Figure 41.JH (a) and13C (b) NMR spectra of MeNBT in CDCh. is solvent peak.

[0065] Figure 42.JH (a) and13C (b) NMR spectra of BocBT in CDCh. is solvent 20 peak.

[0066] Figure 43.JH (a) and13C (b) NMR spectra of IBocBT in CDCh. is solvent peak.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0067] Figure 44.JH (a) and13C (b) NMR spectra of zPrBocBT in CDCh. is solvent peak.

[0068] Figure 45.JH (a) and13C (b) NMR spectra of zPrBrBocBT in CDCh. is solvent peak.

[0069] 5 Figure 46.JH (a)13C (b) and19F (c) NMR spectra of BocBTFCp in CDCh.

[0070] is solvent peak. Carbon signals related to perfluorocyclopentene broadened by19F coupling.

[0071] Figure 47.JH (a) and13C (b) NMR spectra of BrTh in CDCh. is solvent peak.

[0072] 10 Figure 48.JH (a) and13C (b) NMR spectra of BrThPy in CDCh. is solvent peak.

[0073] Figure 49. 'H NMR spectra of BocDEo in DMSO-d6. is solvent peak, (a) 0.0 to 9.0 ppm (b) 7.1 to 8.9 ppm and (c) 0.8 to 3.8 ppm. Green attributions indicate anti-parallel and red indicate parallel isomers. The ratio of anti-parallel / parallel isomer is 55 / 45.

[0074] Figure 50.13C NMR spectra of BocDEo in DMSO-d6. is solvent peak, (a) 10 to 190 ppm (b) 118 to 158 ppm and (c) 15 to 80 ppm. Carbon signals related to perfluorocyclopentene broadened by19F coupling.

[0075] Figure 51.19F NMR spectra of BocDEo in DMSO-d6.

[0076] 20 Figure 52. 'H NMR spectra of BocDEc in DMSO-d6. is solvent peak, (a) 0.0 to 9.0 ppm (b) 7.1 to 8.9 ppm and (c) 0.8 to 3.8 ppm.

[0077] Figure 53.13C NMR spectra of BocDEc in DMSO-d6. is solvent peak, (a)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0078] 10 to 190 ppm (b) 118 to 158 ppm and (c) 15 to 80 ppm. Carbon signals related to perfluorocyclopentene broadened by19F coupling.

[0079] Figure 54.19F NMR spectra of BocDEc in DMSO-d6.

[0080] Figure 55.1H NMR spectra of MeNDEo in DMSO- is. is solvent peak, 5 (a) 0.0 to 9.0 ppm (b) 6.7 to 9.3 ppm and (c) 0.1 to 3.1 ppm. Green attributions indicate anti-parallel and red indicate parallel isomers. The ratio of anti-parallel / parallel = 52.5 / 47.5.

[0081] Figure 56.13C NMR spectra of MeNDEo in DMSO- is. is solvent peak, (a) 10 to 190 ppm (b) 100 to 152 ppm and (c) 8 to 46 ppm. Carbon signals related to 10 perfluorocyclopentene broadened by19F coupling.

[0082] Figure 57.19F NMR spectra of MeNDE in DMSO- k

[0083] Figure 58. 'H NMR spectra of DEo in DMSO- k is solvent peak, (a) 0.0 to 9.0 ppm (b) 7.1 to 8.9 ppm and (c) 0.6 to 4.6 ppm. Green attributions indicate antiparallel and red indicate parallel isomers. The ratio of anti-parallel / parallel = 55 / 45.

[0084] Figure 59. 'H - 'H NOESYNMR spectra of DEo in DMSO-t / e 7.60 to 7.96 ppm vs 1.75 to 2.20 ppm. Green attributions indicate anti-parallel (DEoap) and red indicate parallel (DEoP) isomers. The NOE correlations of the benzo[b]thiophene 4- position proton c revealed that in the anti-parallel isomer (DEoap), a cross-peak with the thiophene 2-position methyl protons j was observed, whereas in the parallel 20 isomer (DEoP), a correlation with the thiophene 4-position methyl protons was detected. These NOE correlations clearly support the respective stereostructures. Furthermore, each resonance was assigned by 2D HSQC and HMBC experiments,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0085] and the integrals of the assigned signals were in good agreement with the calculated population ratio of 55 / 45.

[0086] Figure 60.13C NMR spectra of DEo in DMSO- k is solvent peak, (a) 10 to 190 ppm (b) 115 to 195 ppm and (c) 5 to 55 ppm. Carbon signals related to 5 perfluorocyclopentene broadened by19F coupling.

[0087] Figure 61.19F NMR spectra of DEo in DMSO- k

[0088] Figure 62.1H -13C HSQC NMR spectra of DEo in DMSO4. (a) 7.1 to 8.8 ppm vs 120 to 152 ppm (b) 0.4 to 4.4 ppm

[0089] Figure 63.

[0090]

[0091] -13C HMBC NMR spectra of DEo in DMSO-fifc. (a) 0.0 to 4.5 10 ppm vs 110 to 200 ppm (b) 2.0 to 8.5 ppm vs 114 to 142 ppm.

[0092] Figure 64. 'H NMR spectra of DEc in DMSO- k is solvent peak, (a) 0 to 9.0 ppm (b) 7.1 to 8.9 ppm and (c) 0.8 to 4.8 ppm.

[0093] Figure 65.13C NMR spectra of DEc in DMSO- k is solvent peak, (a) 10 to 190 ppm (b) 125 to 195 ppm and (c) 12 to 72 ppm.

[0094] Figure 66.19F NMR spectra of DEc in DMSO- k

[0095] Figure 67. 'H -13C HSQC NMR spectra of DEo in DMSO4. (a) 6.9 to 8.9 ppm vs 120 to 152 ppm (b) 0.8 to 4.4 ppm.

[0096] Figure 68. 'H -13C HMBC NMR spectra of DEo in DMSO-d6. (a) 0.0 to 4.5 ppm vs 80 to 200 ppm (b) 6.4 to 9.4 ppm vs 120 to 160 ppm.

[0097] 20 Figure 69. 400 MHz 'H NMR spectra of DEo (20 mM in CD3CN) under UV irradiation (1 = 302 nm, Intensity = 2.8 mW / cm2) at different time points from before irradiation to 90 min. Bottom spectrum was shown as isolated DEo which wasPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0098] detected as a mixture of anti-parallel isomer DEoapand parallel isomer DEoP. After 90 min, the conversion of DEc compared to DEo reached 64%.

[0099] Figure 70. 400 MHz 'H NMR spectra of DEc (20 mM in CD3CN) under visible light irradiation (1 = 530 nm, Intensity = 56 mW / cm2) at different time points 5 from before irradiation to 35 min. DEc was quantitatively converted to DEo and reaching a thermodynamic equilibrium between anti-parallel isomer DEoapand parallel isomer DEoPas 50 / 50 molar ratio.

[0100] Figure 71. (a) UV-vis absorption spectra of DEc in acetonitrile at different concentrations (0.020, 0.015, 0.010, 0.005, and 0.0025 mM), and (b) the calibration 10 curve constructed from the absorbance at 556 nm versus concentration (right). The molar absorption coefficient (a) at 556 nm was determined to be 1.16 x 104M1

[0101]

[0102] cm Figure 72. (a) Kinetics of the photoisomerization from DEo to DEc monitored by UV-vis absorption at 556 nm under UV irradiation (1 = 302 nm, 2.8 mW cm2). The concentration of DEc, normalized to the prepared sample concentration (0.020 mM), increased rapidly within the first few minutes and reached a photo-stationary state (PSS) corresponding to a conversion of 0.78.

[0103] (b) Kinetics of the reverse photoisomerization from DEc to DEo under visible-light irradiation (1 = 530 nm, 56 mW cm2). The normalized DEc concentration decreased to nearly zero within 3 min, although the decay did not proceed strictly linearly. The 20 rate of change appeared to slow as the concentration of DEc decreased, a tendency that may be related to factors such as effective absorption cross-section or light penetration at lower concentrations.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0104] Figure 73. 400 MHz 'H NMR spectra of DEc in DMSO-d6(a) before, (b) after thermal treatment. The NMR sample was heated in an oil bath at 75 °C for 24 h under dark conditions to evaluate the thermal stability of DEo and DEc. No detectable changes were observed in the spectra, indicating that DEc and DEo were thermally 5 stable under these conditions.

[0105] Figure 74. 400 MHz 'H NMR spectra of poly(dodecyl acrylate) polymerized with (a) BocDEo, (b) BocDEc, and (c) without additives, after precipitation in methanol. No detectable signals corresponding to the diarylethene backbone were observed in the spectra, indicating that the diarylethene units did not affect the 10 polymerization.

[0106] Figure 75. 500MHz 'H NMR spectra of poly(dodecyl acrylate) having DEc chain end (DEcPDDA) in CDCh.

[0107] Figure 76. 500 MHz 'H NMR spectra of poly(dodecyl acrylate) having DEo chain end (DEoPDDA) in CDCh.

[0108] Figure 77. 600MHz DOSY1H NMR spectrum of DEoPDDA in measured in CDCh at 25 °C. The diffusion coefficients of signals corresponding to DEo, poly(dodecyl acrylate) moieties (8.63 - 7.20 ppm, 4.72 ppm and 4.01 ppm) were identical (D = 1.47 * 106m2 / s), indicating that both segments are covalently linked within the same polymer chain.

[0109] 20 Figure 78. 600MHz 'H NMR spectra of PDDA-b-PVAc in CDCh.

[0110] Figure 79. 600MHz DOSY 'HNMR spectrum of PDDA-Z>-PVAc in measured in CDCh at 25 °C. The diffusion coefficients of signals corresponding toPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0111] DEo, poly(vinyl acetate) and poly(dodecyl acrylate) moieties (8.51 - 7.11 ppm, 4.95 ppm and 3.99 ppm) were identical (D = 6.42 * 107m2 / s), indicating that both segments are covalently linked within the same polymer chain.

[0112] Figure 80. Thin-layer chromatography analysis of the as-synthesized PDDA- 5 Z>-PVAc diblock copolymer using UV light. Solvent polarity increases from left to right with increasing vol% of THF in toluene. Characteristic streaking seen at 40% and 60% THF in toluene is indicative of solvent strength amendable to chromatographic fractionation.

[0113] Figure 81. Weight of fractions (black) over the course of the separation of the 10 as-synthesized PDDA-Z>-PVAc diblock copolymer with elution primarily occurring around 40% THF in toluene. A near-quantitative mass recovery of 93% was observed. The blue trace is the solvent composition increasing from 33% THF in toluene to 66% THF in toluene over the course of the separation

[0114] Figure 82. Representative 600MHz 'H NMR of the as-synthesized material and resulting samples post chromatographic fractionation. The blue represents the PVAc resonance and the red represents the PDDA resonance used.

[0115] Figure 83. Representative size-exclusion chromatography elugrams of the as- synthesized material and resulting samples post chromatographic fractionation. The dashed black line represents the as-synthesized material, and the solid lines refer to 20 the samples.

[0116] Figure 84. Representative fit of the SAXS data using the random phase approximation. All listed parameters besides χN and f were fixed.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0117] Figure 85. Plot used to extract the temperature dependency of f. To limit fluctuation effects, the regression was only performed for T > 100 °C.

[0118] Figure 86. Supplementary scheme 9

[0119] Figure 87. Supplementary Scheme 10.

[0120] 5 Figure 88. Supplementary Scheme 11.

[0121] Figure 89. Supplementary scheme 12

[0122] Figure 90. Supplementary Scheme 13.

[0123] Figure 91. Supplementary Scheme 14.

[0124] Figure 92. Supplementary Scheme 15.

[0125] 10 Figure 93. Supplementary scheme 16.

[0126] Figure 94. Supplementary Scheme 17.

[0127] Figure 95. Supplementary Scheme 18.

[0128] Figure 96. Supplementary Scheme 19.

[0129] Figure 97. Flowchart illustrating a method of making a copolymer.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0130] DETAILED DESCRIPTION OF THE INVENTION

[0131] In the following description of the preferred embodiment, reference is made to the accompanying drawings which form a part hereof, and in which is shown by

[0132] 5 way of illustration a specific embodiment in which the invention may be practiced. It

[0133] is to be understood that other embodiments may be utilized, and structural changes

[0134] may be made without departing from the scope of the present invention.

[0135] Technical Description

[0136] 10 General requirement for the RAFT agent

[0137] The chemical structure of the RAFT agent described in the present invention is represented by the following general formulas (I) or (II).

[0138]

[0139] In these general formulas (I) and (II), X can be either a sulfur atom or an

[0140] 15 oxygen atom; however, in one or more embodiments, from the chemical stability of

[0141] the ring-closed form, sulfur is preferred.

[0142] In the general formulas (I) and (II), Y can be a substituted nitrogen or an

[0143] oxygen atom, or a sulfur atom, or nothing; however, in one or more embodiments,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0144] from the stability against hydrolysis of the RAFT reagent, a substituted nitrogen is preferred. Specific examples of substituents on the nitrogen which include alkyl groups having from 1 to 12 carbon atoms or aryl groups. In one or more embodiments, nitrogen which includes a methyl group is particularly preferred 5 because it has low electron-donating properties and imposes less steric hindrance on the dithiocarbamate moiety to increase polymerization control.

[0145] In the general formulas (I) and (II), R1functions as an acceptor that reduces the electron density of the dithiocarbamate when the RAFT reagent is ring-closed form. Therefore, in one or more embodiments, an aryl group or fluoroalkyl group with 10 as much electron-withdrawing character as possible is preferred, although an alkyl group having from 1 to 12 carbon atoms can also be used.

[0146] Examples of aryl groups include phenyl groups having from 0 to 5 substituents, pyridyl or quatemized pyridinium groups having from 0 to 4 substituents, pentafluorophenyl and perfluorotolyl groups. Possible substituents include alkyl groups having from 1 to 12 carbon atoms, fluoro groups, cyano groups, trifluoromethyl groups, sulfonate groups, ketone groups, carboxylate groups and nitro groups. Among these, pyridyl or N-methyl-2,6-dimethylpyridinium groups are particularly preferred because of their high electron-withdrawing properties and low tendency to cause side reactions during polymerization. Specific examples of

[0147] 20 fluoroalkyl groups include perfluoroalkyl groups having from 1 to 12 carbon atoms.

[0148] In the general formulas (I) and (II), R2can be an alkyl group, fluoroalkyl group, or aryl group having from 1 to 12 carbon atoms. In one or more embodiments,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0149] a methyl group is preferred due to its low electron-donating properties. When R2is hydrogen, the ring-closed form becomes reactive toward some radicals, thereby reducing polymerization control, and is thus can be unsuitable.

[0150] In the general formulas (I) and (II), R3and R4can be alkyl groups, aryl groups, 5 fluoroalkyl groups, or fluoroaryl groups having from 1 to 12 carbon atoms. In one or more embodiments, methyl, ethyl, n-propyl, or isopropyl groups are more preferred because they do not significantly hinder the approach of the carbons connected to R3when the RAFT agent isomerizes to its ring-closed form.

[0151] In general formula (II), R5is preferably an alkyl group having from 1 to 12 10 carbon atoms because it increases the electron density of the dithiocarbamate moiety in the open-ring form, thereby improving the control of LAM polymerization.

[0152] When R5is hydrogen, the ring-closed form becomes reactive toward some radicals, thereby reducing polymerization control, and is thus can be unsuitable.

[0153] In the general formulas (I) and (II), R6in the general formulas I and II can be 15 selected according to the reactivity of the monomer used. In one or more embodiments, in the polymerization of methacrylate, which gives stable growing radicals, 2-cyanopropyl group is preferred. In the polymerization of acrylate, styrene, vinylester and vinylamide, which gives moderately to unstable growing radicals, 2-PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0154] methoxycarbonylpropyl group, 2 -methoxycarbonyl ethyl group, 2-cyanoethyl group, and cyanomethyl group are preferred.

[0155] In general formula (I), Ar can be a monocyclic, bicyclic or large aromatic moiety. In some examples, Ar is preferably absent or is a phenylene group.

[0156] 5 In general formula (II), Ar can be a monocyclic, bicyclic or large aromatic moiety. In some examples, Ar is preferably a benzene ring.

[0157] Monomers

[0158] The RAFT agent described in this invention controls the polymerization of 10 non-conjugated monomers in ring-opened form and conjugated monomers in ring- closed form. Examples of non-conjugated monomers that can be used are vinyl esters (e.g. vinyl acetate and vinyl chloroacetate) with a formula of CH2CHOCOR, vinyl amides with a formula of CH2CHN(R’)COR and vinyl ethers (e.g. methyl vinyl ether, ethyl vinyl ether and iso-butyl vinyl ether) with a formula of CH2CHOR, and examples of conjugated monomers that can be used are acrylates (e.g. methyl acrylate, ethyl acrylate, butyl acrylate, decyl acrylate, or dodecyl acrylate) with a formula of CH2CHCOOR, methacrylates with a formula of CH2C(CH3)COOR, styrene and acrylamides with a formula of CH2CHCONR.’ R., and their derivatives. In one or more embodiments, R and R’ are independently an alkyl group with a formula of - 20 CnH2n+i, while n is an integer of 0 to 30, or 2 to 30, or 4 to 30, or 5 to 30. In one or more embodiments, R and R’ are independently a cyclic alkyl group with a formula of -CnH2n-i, while n is an integer of 3 to 30, or 4 to 30, or 5 to 30. In one or morePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0159] embodiments, R and R’ further comprise one or more alkene or alkenylene groups, alkynyl or alkynylene groups, aryl or arylene groups, heteroaryl or heteroarylene groups. In one or more embodiments, R and R’ further comprise one or more heteroatoms including but not limited to halogens (F, Cl, Br, I), Boron, Silicon, 5 Germanium, Nitrogen, Phosphorus, Arsenic, Oxygen, Sulfur, Selenium, and Tellurium. In one or more embodiments, R and R’ further comprise ionic groups, including but not limited to sulfonates, carboxylates, phosphonates, ammoniums and pyridiniums.

[0160] 10 Solvents

[0161] The polymerization conditions may be those commonly employed for conventional radical polymerizations. The solvent is not particularly limited as long as it can satisfactorily dissolve the RAFT agent, the initiator, the monomer, and the resulting polymer. Examples include water; aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; aromatic halides such as chlorobenzene and bromobenzene; ester compounds such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and amyl acetate; alcohols such as methanol, ethanol, propanol, and butanol; ketones such as acetone and 2-propanone; and fluorinated solvents such as 2,2,2-trifluoroethanol and 1,1,1,3,3,3-hexafluoroisopropanol. In one or more

[0162] 20 embodiments, water, toluene, xylene, ethyl acetate, butyl acetate, ethanol, propanol, acetone, 2-propanone, 2,2,2-trifluoroethanol, and 1,1,1,3,3,3-hexafluoroisopropanol are preferred because they effectively dissolve the RAFT agent, monomers, andPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0163] polymers used in the present invention. In one or more embodiments, industrial friendly and environmentally friendly solvents are preferred. The monomer concentration in the solvent during polymerization is preferably 0.1 M to 10 M, more preferably 0.5 M to 9 M, and most preferably 1 M to 8 M. When the monomer 5 concentration is below 0.1 M, the polymerization may not proceed efficiently, whereas concentrations exceeding 10 M, it may cause gelation or solidification of the reaction mixture and lead to deterioration of the molecular weight distribution.

[0164] Initiators

[0165] 10 The initiator used in the polymerization of the present invention is not particularly limited, and any radical initiator commonly employed in radical polymerizations may be used. In one or more embodiments, azo-type initiators such as 2,2'-azobis(isobutyronitrile) (AIBN), dimethyl 2,2'-azobis(2-methylpropionate) (V- 601), l,l'-azobis(cy cl ohexane-1 -carbonitrile) (V-40), 2,2'-azobis(4-methoxy-2,4- dimethylvaleronitrile) (V-70), 2,2'-azobis(2,4-dimethylvaleronitrile) (V-65), 2,2'- azobis(2-methylbutyronitrile) (V-59), 2,2'-azobis[N-(2-carboxyethyl)-2- methylpropionamidine] tetrahydrate (VA-57), 2,2'-azobis[2-methyl-N-(2- hydroxyethyl)propionamide] (VA-86), 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (VA- 61), 2,2'-azobis(2-methylpropionamidine) dihydrochloride (V-50), 2,2'-azobis[2-(2- 20 imidazolin-2-yl)propane] dihydrochloride (VA-044), and 4,4'-azobis(4-cyanovaleric acid) (V-501) are preferred because they generate radicals in a controlled manner without oxidative degradation of the RAFT agent, thereby enabling good control ofPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0166] the molecular weight and dispersity of the resulting polymer.

[0167] In some further embodiments, AIBN, V-601, V-40, V-70, and V-501 are more preferred because their 10-hour half-life temperatures fall within the range of 30- 80 °C, providing a sufficiently high polymerization rate while suppressing

[0168] 5 degradation of the RAFT agent during the reaction.

[0169] In one or more embodiments, the amount of initiator is preferably 0.01 to 1.0 equivalents relative to 1.0 equivalent of the RAFT agent, and more preferably 0.05 to 0.5 equivalents. When the amount of initiator is below 0.01 equivalents, the polymerization may not proceed efficiently, whereas amounts exceeding 1.0

[0170] 10 equivalent, it may lead to deterioration of the molecular weight distribution.

[0171] Polymerization

[0172] Polymerization conditions may employ any conventional radical polymerization method for vinyl monomers. Examples include solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization. In one or more embodiments, solution polymerization is preferred because it allows the reaction to proceed gently and affords polymers with good molecular weight distribution.

[0173] The polymerization temperature may be appropriately adjusted with

[0174] 20 reference to the 10-hour half-life temperature of the initiator; In one or more embodiments, a temperature in the range of 30 °C to 100 °C is preferred, as it enables smooth polymerization and provides polymers with favorable molecular weightPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0175] distribution.

[0176] Isomerization

[0177] The RAFT agent described in this invention isomerizes to ring-closed form 5 by UV irradiation of the ring-opened form. In addition, irradiation with visible light causes isomerization from the ring-closed form to the ring-opened form. The wavelength of ultraviolet light used here is not particularly limited. In one or more embodiments, a wavelength of 280 nm to 380 nm is preferred; below 280 nm, there is concern that the RAFT agent may be decomposed by high-energy UV irradiation, and 10 above 380 nm, it is closer to the visible light region, so that the isomerized ring-closed form may be partially ring-opened. Partially isomerized to ring-opened form, resulting in lower isomerization efficiency. In one or more embodiments, visible light wavelengths of 380 nm and above and 700 nm and below are preferred; below 380 nm, the ring-opened form partially isomerizes to the ring-closed form, resulting in lower isomerization efficiency. Above 700 nm, the light energy is too low, also resulting in lower isomerization efficiency. The intensity of the irradiated ultraviolet or visible light is not particularly limited, and commercially available light sources can be used as appropriate. In one or more embodiments, 0.05 (mW / cm2) to 200 (mW / cm2) is preferred.

[0178] 20 Photoisomerization of the RAFT agent can be performed in either solid or solution form. In one or more embodiments, the diluted solution form is preferred because it shortens the isomerization time. In one or more embodiments, thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0179] concentration of the RAFT agent in solution is between 0.1 mM and 50 mM. If the concentration is too low, isomerization proceeds quickly, but subsequent solvent removal can be complicated. If the concentration is too high, isomerization can take a long time. The solvent used is not limited as long as it dissolves the RAFT agent. In 5 one or more embodiments, a solvent with an absorption wavelength that does not overlap with the absorption wavelength of the RAFT agent and is inert to photoreaction is preferred. Specifically, acetone, methanol, ethyl acetate, dichloromethane, and hexane are examples.

[0180] 10 Example RAFT Agent

[0181] Fig. la illustrates a composition of matter 100 (e.g., RAFT agent) useful in a RAFT polymerization process, comprising a RAFT moiety 102 coupled (e.g., covalently bonded) to an electron acceptor 104 and a photo-switchable compound 106. Alternatively, a RAFT agent 101 can be defined as comprising an electron acceptor 104 (in this example pyridine) connected to a dithiocarbamate 105 via a photo-switchable compound 106 (e.g., photochromic diaryl ethene, it can also be called a photo-switchable moiety, unit or functional group).

[0182] In one or more embodiments, a RAFT moiety refers to the key functional group in a RAFT agent comprising the thiocarbonylthio structure. It can comprise but 20 not be limited to a dithiocarbamate, a xanthate, a dithiocarbonate, a dithiobenzoate, a dithioester, or a trithiocarbonate.

[0183] The example RAFT agent (comprising pyridine connected to dithiocarbamatePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0184] via photochromic diarylethene) was synthesized and its polymerization behavior toward MAMs and LAMs was evaluated. The produced RAFT agent has two isomers, a ring-opened (named DEo, also DE9o) and a ring-closed (named DEc, also DE9c) isomer derived from diarylethene, and each isomer can be switched by UV (e.g. 1 = 5 302 nm) and Vis (e.g. 530 nm) irradiation respectively. In DEo, the acceptor and RAFT agent are not electronically connected and thus exhibit controlled polymerization properties toward vinyl esters as dithiocarbamates. In DEc, the electron density of the RAFT agent is reduced due to the electron-withdrawing nature of the acceptor via the n conjugated system of diarylethene (plus the

[0185] 10 perfluorocyclopentene moiety is also electron-withdrawing), and showed controlled polymerization properties towards acrylate monomers.

[0186] 1. The kinetics of VAc polymerization using DE9o

[0187] The relationship between polymerization time and conversion, and conversion relative to molecular weight and poly dispersity were confirmed as a guide 15 of VAc polymerization (Scheme 1).

[0188] ^^OAc (100 equiv.)

[0189] PVAc V-40 (0.32 equiv.) " AcOEt (6 M), 75 °C

[0190]

[0191] DE9o (1 equiv.)

[0192] Scheme 1. VAc polymerization using DE9o.

[0193] a. Polymerization conditionsPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0194] A 4 mL glass vial charged with DE9o (55.0 mg, 0.075 mmol, 1 equiv.), 1,1’- azobis(cyclohexane carbonitrile) (V-40) (5.81 mg, 0.024 mmol, 0.32 equiv.), vinyl acetate (700 pL, 7.5 mmol, 100 equiv.), and ethyl acetate (560 pF) was used as stock solution. Each 200 pL of stock solution was charged to 2 mL amber glass ampules.

[0195] 5 These ampules were connected to the Schlenk line and three cycles of freeze-pump- thaw to remove air. Ampules were sealed under reduced pressure. The polymerization was performed at 75 °C. and using (DE9o / VAc / V-40 = 1 / 100 / 0.3, [VAc] = 6 M)

[0196] b. Results and discussion

[0197] 10 Figure 1 and Table 1 show the polymerization results. Mnand poly dispersity (Đ) were determined by GPC (eluent: CHCh, equivalented by PSt standard).

[0198] Monomer conversion was determined by1H NMR (CDCh). Each GPC peak has UV absorbance originating from diarylethene. Monomer conversion exponentially increased from 10 h and slowed down around 30 h. Mnincreased linearly following 15 theoretical values and D was kept low of around 1.4. (Figure 2a, 2b). According to1H NMR spectrum, the DE9o moiety incorporated into the PVAc (Figure 3). These results indicate that DE9o controls VAc polymerization.

[0199] 2. The kinetics of PMA polymerization using DE9o and DE9cPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0200] The relationship between polymerization time and conversion, and conversion relative to molecular weight and poly dispersity were confirmed as a guide for PMA polymerization (Scheme 2).

[0201] •^^s''CO2Me (100 equiv.)

[0202] . PMA AIBN (0.05 equiv.) TFE (4 M), 70 °C

[0203] F F

[0204] •^^s''CO2Me (100 equiv.) PMA AIBN (0.05 equiv.) TFE (4 M), 70 °C

[0205]

[0206] DE9c (1 equiv.)

[0207] 5 Scheme 2. PMA polymerization using DE9o and DE9c.

[0208] a. Polymerization conditions

[0209] A 4 mL glass vial charged with DE9o or DE9c (36.7 mg, 0.050 mmol, 1 equiv.), AIBN (0.41 mg, 0.0025 mmol, 0.05 equiv.), methyl acrylate (456 pL, 5.0 10 mmol, 100 equiv.), and 2,2,2-trifluoroethanol (TFE, 800 pL) was used as stock solution. Each 300 pL of stock solution was charged to four 2 mL amber glass ampules. These ampules were connected to the Schlenk line and applied three cycles of freeze-pump-thaw to remove air. Ampules were sealed under reduced pressure. ThePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0210] polymerization was performed at 70 °C using (DE9c or DE9o / MA / AIBN = 1 / 100 / 0.05, [MA]= 4 M).

[0211] b. Results and discussion

[0212] 5 Figure 4 and Table 2 show the polymerization results of DE9o. Mnand poly dispersity (Đ) were determined by GPC (eluent: CHCh, equivalented by PSt standard). Monomer conversion was determined by1H NMR in CDCh (These processes are same to DE9c). Each GPC peak has UV absorbance originating from diarylethene. Monomer conversion exponentially increased from 1 h and slowed 10 down around 3 h. Mnwas kept almost around 12 kDa during polymerization, and D was kept around 1.8-1.9.

[0213] In contrast, polymerization using DE9c exhibited different results (Figure 5 and Table 3). Monomer conversion at 1 h was the same as for DE9o but afterwards the conversion increased linearly over time and reached to 81% at 4 h. Mnincreases monotonically according to monomer conversion and D was much lower (1.5) as compared to that achieved for DE9o. According to these results, the control ability of the polymerization using DE9c is higher than when using DE9o. The results are summarized in Figure 6a and 6b.

[0214] However, Mnof PMA when using DE9c as RAFT agent is still higher than 20 theoretical values. We hypothesize that addition of polymer chain to monomer was still faster than the chain transfer reaction mediated by the RAFT agent. We hypothesize if the electron withdrawing ability of the acceptor side on the DE9cPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0215] moiety can be made stronger, Mnshould be closer to the theoretical values due to the increase of chain transfer constant.

[0216] Next, PMA polymerized by DE9c (DE9cPMA) was controllably isomerized using Vis (1= 530 nm) irradiation without side reactions.

[0217] 5

[0218] 3. Photo-switching behavior of DE9cPMA

[0219] Isomerization of DE9cPMAto DE9oPMA was initiated by irradiation with Vis (1 = 530 nm) light as shown below in Scheme 4.

[0220]

[0221] 10 Scheme 4 (Fig. 29). Isomerization of DE9cPMAto DE9oPMAby irradiation of visible light.

[0222] a. Isomerization condition

[0223] A 40 mL glass vial was charged with DE9cPMA (Mn10.6 kDa, D 1.5, 50 15 mg, 4.7 pmol), CHCh (30 mL) as a 0.16 mM solution. The solution was irradiated with visible light (Vis (λ = 530 nm, 170 mW / cm2)) for 5 min. After reaction, the color of solution was changed from purple to colorless. After evaporation DE9oPMA was obtained as a colorless sticky paste.

[0224] 20 b. Results and discussionPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0225] Figure 7 shows the 1HNMR spectra of DE9cPMA, and DE9oPMA which were achieved via isomerization from DE9cPMA. After visible light irradiation, the DE9c moiety was completely changed to DE9o (as a mixture of parallel and antiparallel conformations). Each proton signal was assigned as expected. Figure 8a, 8b 5 (Table 4) also confirm the complete photo-isomerization of DE9cPMAto DE9oPMA without any side reactions, supported by the perfect match of the GPC trace, Mnand D before and after photo-isomerization.

[0226] 4. Controlled polymerization of polv(dodecyl acrylate) and with

[0227] 10 DE9cPDDA as macro-CTA for VAc polymerization in the next example.

[0228] In this example, the positive results of PMA controlled polymerization were applied to MAM-LAM block copolymerization. The results presented herein suggest that block copolymers synthesized using photo-switchable RAFT processes as described herein should exhibit superior and defined phase separation. Therefore, 15 PDDA macro-CTA (DE9cPDDA) was synthesized for the copolymerization, which is expected to exhibit good phase separation from PVAc block.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0229]

[0230] Scheme 5 (Fig. 30). DDA polymerization using DE9c and Photo-isomerization of DE9cPDDA.

[0231] a. Polymerization conditions

[0232] 5 A 2 mL amber glass ampule equipped with stir bar was charged with DE9c (35.3 mg, 0.048 mmol, 1 equiv.), AIBN (0.40 mg, 0.0024 mmol, 0.05 equiv.), dodecyl acrylate (660 pL, 4.8 mmol, 50 equiv.), and toluene (440 pL). The ampule was connected to the Schlenk line and three cycles of freeze-pump-thaw were performed to remove air. The ampule was sealed under reduced pressure. The polymerization 10 was performed at 70 °C. After 2.5 h, the resulting mixture was poured into methanol and the precipitate was collected and washed with methanol. After drying, DE9cPDDA was obtained as a purple sticky oil (360 mg).

[0233] The reaction mixture had the following molarity or concentration (DE9c / DDA / AIBN = 1 / 50 / 0.05, [DDA] = 2.3 M)

[0234] 15

[0235] b. Isomerization conditionsPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0236] DE9cPDDA(M: 8.9 kDa, £>: 1.56, 200 mg), was dissolved in CHCh (120 mL). The resulting solution was irradiated with visible light (Vis (λ = 530 nm, 170 mW / cm2)) for 5 min. After reaction the color of solution was changed from purple to colorless. After evaporation, DE9oPDDA was obtained as a colorless sticky solid (200 5 mg).

[0237] c. Results and discussion

[0238] Figure 10 shows1H NMR spectra of DE9cPDDA and DE9oPDDA which were obtained via photo-isomerization from DE9cPDDA. After visible light

[0239] 10 irradiation, DE9c moiety was completely changed to DE9o (as a mixture of parallel and anti-parallel conformations). Each proton signal was assigned as expected. Figure 9 and Table 5 also confirmed the complete isomerization of DE9cPDDAto DE9oPDDA without any side reactions, supported by the perfect match of the GPC trace, Mnand D before and after photo-isomerization.

[0240] 15

[0241] 5. Synthesis of PDDA-Z>-PVAc block copolymer using DE9oPDDA as the macro CTA

[0242] A block copolymer which has PDDA and PVAc moi eties was synthesized (Scheme 6).PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0243]

[0244] Scheme 6 (Fig. 31). VAc polymerization using DE9oPDDA as macro-CTA.

[0245] a. Polymerization conditions

[0246] 5 A 2 mL amber glass ampule equipped with stir bar was charged with DE9oPDDA (: 8.9 kDa, £>: 1.56, 184 mg, 0.021 mmol, 1 equiv.), V-40 (1.60 mg, 0.0065 mmol, 0.32 equiv.), vinyl acetate (190 pL, 2.1 mmol, 100 equiv.), and ethyl acetate (150 pL). The ampule was connected to the Schlenk line and three cycles of freeze-pump-thaw were performed to remove air. The ampule was sealed under 10 reduced pressure. The polymerization was performed at 75 °C. After 37 h, volatile fractions (solvent, unreacted monomers etc.) were removed under reduced pressure to obtain DE9oPDDA-Z>-PVAc as a pale-yellow sticky solid.

[0247] The concentration of the reaction solution wasPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0248] (DE9oPDDA / VAc / V-40 = 1 / 100 / 0.3, [VAc] = 6 M)

[0249] b. Results and discussion

[0250] Figure 11 and Table 6 show the polymerization results. Mnand 5 poly dispersity (Đ) were determined by GPC (eluent: CHCh, equivalented by PSt standard). Monomer conversion was determined by1H NMR (CDCI3). The GPC peak of block copolymer (DE9oPDDA-Z>-PVAc) shifted from the parent polymer (DE9oPDDA) peak. Maof the block polymer followed theoretical predictions and D was 1.51. Assignments in the1H NMR spectra in Figure 12 show that the polymer has 10 DE9o, PVAc and PDDA moieties.

[0251] In summary, polymerization kinetics of VAc with DE9o and MA with DE9o and DE9c were investigated. DE9o provided well-controlled PVAc due to dithiocarbamate reactivity of DE9o. On the other hand, controlled polymerization of MA and DDA was achieved using DE9c. Acrylates which have DE9c were completely converted to macro-CTA which has the DE9o moiety by visible light irradiation. Macro-CTA (DE9oPDDA) was combined with VAc polymerization to obtain the diblock copolymer (DE9oPDDA-Z>-PVAc).

[0252] 6. Additional data

[0253] 20 Synthesis of DE9

[0254] DE9o was synthesized following the scheme 7 in Fig 13.

[0255] Preparation of 2,4-dibromo-3,5-dimethylthiophene:PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0256] NBS

[0257]

[0258] MeCN, 0 °C to r.t., 3 h 97% yield.

[0259] A 50 mL round bottom flask charged with 2,4-dimethylthiophene (1.12 g, 10 mmol) and acetonitrile (10 mL) was stirred in ice bath for 10 min. NBS (3.58 g, 20 mmol) was slowly added. After the ice bath was removed, the mixture was stirred for 3 5 h. After the reaction, the mixture was poured into water and extracted with hexane and washed with water, and brine. The organic layer was dried by MgSO4. After filtration solvent was evaporated under reduced pressure to obtain 2,4-dibromo-3,5- dimethylthiophene as yellow oil. 1.78 g, 97% Yield.

[0260] Figure 14 shows ’H NMR spectra of 2,4-dibromo-3,5-dimethylthiophene (400 10 MHz CDCh).

[0261] Preparation of BrThPy

[0262]

[0263] 72% yield.

[0264] 15 A 50 mL round bottom flask charged with argon, Potassium carbonate (2.07 g 15 mmol), tetrakis(triphenylphosphine)palladium (173 mg, 0.15 mmol), pyridine-4- boronic acid (615 mg, 5.0 mmol) and 2,4-dibromo-3,5-dimethylthiophene (1.35 g, 5.0PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0265] mmol) was suspended in 1,4-di oxane (20 mL) and water (5 mL). The reaction mixture was stirred at 90 °C for 16 h. After the reaction, the mixture was extracted by dichloromethane and the organic layer was washed with water and brine and dried over MgSO4. After filtration, solvent was evaporated under reduced pressure. The residue 5 was purified by silica gel column chromatography (eluent was / / -Hexane / AcOEt 0 to 35%). After drying, BrThPy was obtained as Light-yellow powder. 968.2 mg, 72% Yield.

[0266] Figure 15 shows 'H NMR. spectra of BrThPy (400 MHz CDCh).

[0267] Preparation of BocDE9o

[0268]

[0269] BocDE9 50% yield.

[0270] A flame dried 30 mL Schlenk flask charged with BrThPy (113 mg, 0.42 mmol) and dry THF (2 mL) was stirred in dry ice methanol bath (-78 °C) for 10 min 15 under argon atmosphere. / / -BuLi (2.0 M in cyclohexane, 0.22 mL, 0.44 mmol) was dropped slowly into the solution. The mixture was stirred at -78 °C for 40 min. After confirming by 'H NMR that lithiation was almost complete, 2 mL THF solution ofPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0271] zPrBocBTFCp (209 mg, 0.42 mmol) was dropped and stirred for 24h while keeping the temperature. After the reaction, mixture was poured into sat. NH4Q aq. and extracted with ether and washed with water, and brine. Organic layer was dried by MgSO4. After filtration solvent was evaporated under reduced pressure, and residue was purified by 5 the silica gel column chromatography (eluent was / / -Hexane / AcOEt 0 to 30%). After drying, BocDE9o was obtained as pale-yellow solid. 141.3 mg, 50% Yield.

[0272] Figure 16 shows 'HNMR spectra of BocDE9o (500 MHz DMSO-d6).

[0273] 10 Preparation of BocDE9c (Fig, 32)

[0274] UV (λ = 302 nm) 1h Acetone

[0275]

[0276] A 1.5 mL quartz cell (path length 5 mm) equipped with a stir bar was charged withBocDE9o (15 mg) and acetone (1.5 mL). The reaction mixture was stirred at room 15 temperature under the irradiation of UV (302 nm) light for 1 h. After evaporation, residue was purified by silica gel column chromatography (eluent was / / -Hexane / AcOEt 0 to 35%). After drying, BocDE9c was obtained as dark purple solid. 10.2 mg, 68% Yield.

[0277] Figure 17 shows 'HNMR spectra of BocDE9c (500 MHz DMSO-d6).

[0278] 20

[0279] Preparation of MeNDE9o (fig, 33)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0280]

[0281] A 30mL round bottom flask charged with BocDE9o (250 mg, 0.40 mmol). TFA 1 mL was added. The reaction mixture was stirred at room temperature for 10 min. After the reaction, mixture was neutralized by NaOH aq. and extracted by ether. The organic 5 layer was washed with brine and dried over MgSO4. After filtration, solvent was removed under reduced pressure to obtain MeNDE9o as pale-yellow oil. 210 mg, 99% Yield.

[0282] Figure 18 shows 'H NMR spectra of MeNDE9o (500 MHz DMSO-tfc).

[0283] 10

[0284] Preparation of DE9o (Fig, 34)

[0285]

[0286] DE9 84% yield. AP / P 54 / 46

[0287] 15 A 4 mL reaction vial with septa was charged with MeNDE9o (74 mg, 0.15PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0288] mmol), lithium chloride (11 mg, 0.26 mmol), THF (0.5 mL). zPrMgCl THF solution (2M 0.13 mL, 0.26 mmol) was added and the reaction mixture was stirred at room temperature for 5 h under argon atmosphere. After 5 h, carbon disulfide (0.027 mL, 0.45 mmol) was added to obtain the dithiocarbamate. Then, methyl 2-bromopropionate 5 (0.052 mL, 0.45 mmol) was added. After evaporation, residue was purified by silica gel column chromatography (eluent was / / -Hexane / AcOEt 0 to 35%). After drying, DE9o was obtained as yellow powder. 80.3mg, 84% Yield.

[0289] Figure 19 shows 'H NMR spectra of DE9o.

[0290] 10

[0291] Preparation of DE9c (Fig, 35)

[0292]

[0293] A 1.5 mL quartz cell (path length 5 mm) equipped with stir bar was charged 15 with DE9o (15 mg) and acetone (1.5 mL). The reaction mixture was stirred at room temperature with irradiating UV (302 nm) for 1 h. After evaporation, residue was purified by silica gel column chromatography (eluent was / / -Hexane / AcOEt 0 to 35%). After drying, DE9c was obtained as a dark purple solid. 4.9 mg, 33% Yield.

[0294] Figure 20 shows *HNMR spectra of DE9c (500 MHz DMSO-d6).PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0295] To confirm that the DE9 diarylethene backbone doesn’t react with radicals in the polymerization, both ring-opened and closed BocDE9 (BocDE9o and BocDE9c) which don’t have the RAFT functional group were synthesized and tested as model molecules. BocDE9c was obtained by photo-isomerization of BocDE9o. Free radical 5 polymerization of methyl acrylate with the addition of BocDE9 was carried out.

[0296] Theoretically, each polymerization is expected to give the same result because

[0297] BocDE9 has no reaction site for radicals.

[0298] <^xCO2Me (200 eq.)

[0299] PMA AIBN (0.2 eq.) MeCN (5M), 70 °C 21 h

[0300] < Ss> KCO2Me (200 eq.)

[0301] PMA AIBN (0.2 eq.) MeCN (5M), 70 °C 21 h

[0302]

[0303] BocDE9c

[0304] Scheme 8. Free radical polymerization of MA with the addition of BocDE9o or

[0305] 10 BocDE9c.

[0306] Figure 21 and Table 7 in Fig. 22 show the result of GPC analysis. The two GPC peaks matched each other and didn’t have UV absorbance origin from diarylethene. There are no side peaks. The molecular weight Mn is larger than thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0307] theoretical value. These results indicate that free radical polymerization was

[0308] proceeded without any side reactions with BocDE9.

[0309] Controlled radical polymerization with DE9

[0310] 5 After confirming that the diaryl ethene backbone of DE9 doesn’t directly interfere with radical polymerization, polymerization of MA using DE9o and DE9c were carried out. DE9c was prepared from DE9o by similar photo isomerization

[0311] method for BocDE9c.

[0312] ^xCO2Me (200 eq.)

[0313] PMA AIBN (0.03 eq.) MeCN (5M), 70 °C 21 h

[0314] P A

[0315]

[0316] 10 Scheme 2. MA polymerization using DE9o and DE9c.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0317] Polymerization condition: A 2 mL amber glass ampule equipped with a stir bar was charged with DE9o or DE9c (4.9 mg, 0.007 mmol), AIBN (0.037 mg, 2× 10−4mmol) acetonitrile (0.29 mL) and methyl acrylate (0.122 mL, 1.3 mmol). After three cycles of freeze-pump-thaw the ampule was sealed under reduced pressure. The 5 polymerization was performed at 70 °C for 21 h. After polymerization1H NMR was measured on both the mixture and purified polymer (precipitation and washed using methanol) to decide the conversion and polymer structure. GPC analysis was performed using the mixture.

[0318] 10 Results and discussion: Fig. 23 and Table 8 in Fig. 24 show the result of GPC analysis. The GPC peak of DE9cPMA was narrower than DE9oPMA, and the remaining DE9c was mostly consumed. In the case of DE9o, polymer peak was wide and some DE9o had remained (peak at 11.5 min.). From the1H NMR of DE9cPMA (Figure 25), PMA backbone has DE9c moiety and number of MA unit (DP) was calculated as 180 (theoretically DP = 185) which doesn’t match the value of GPC. The Mn based on GPC was calibrated by PSt standard, and Mn calculated from NMR can be more accurate. It is supposed that the polymerization conditions such as polymerization temperature, monomer and initiator conditions can be further optimized.

[0319] 20 Figure 25 shows the 1HNMR spectrum of PMA provided from RAFT polymerization using DE9c.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0320] 7. Example Mapping of Phase Separation

[0321] A MAM-LAM block copolymer wherein the polyacrylate and the polyvinylester are phase separated can be synthesized using the RAFT agent described herein. For this example study, the RAFT agent comprises a diarylethene as the 5 photochromic moiety— —, to reversibly modulate the extent of their ^-conjugation upon photoisomerization serving as a trigger to switch RAFT reactivity. As illustrated in Figure 37, the RAFT agent reversibly toggles between a ring-closed form (DEc) and a ring-opened form (DEo) under UV and visible light irradiation. In the DEc state, extended ^-conjugation alters the reactivity of the RAFT center, enabling controlled 10 acrylate polymerization, whereas in the DEo state, electronic decoupling restores dithiocarbamate-like behavior, allowing controlled vinyl ester polymerization.

[0322] In one or more embodiments, this controlled polymerization using the photo- switchable RAFT agent enables high compositional control and purity without multiple controlled radical polymerizations through end-group transformation— —, without employing acid-base responsive RAFT agents— —, or without using RAFT agents with intermediate reactivity toward both MAMs and LAMs— ’—

[0323] By leveraging automated chromatographic fractionation — an established method for constructing high-purity, narrowly dispersed block copolymer libraries— 20 — — a comprehensive mapping of the phase diagram for MAM-LAM diblock copolymers was achieved for the first time. Small-angle X-ray scattering (SAXS)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0324] analysis revealed a continuous sequence of representative microphase morphologies (BCC — G [a low symmetry Frank-Kasper phase previously reported in linear block copolymers] — HEX — GYR — LAM), and critically enabled the unambiguous identification of phases confined to extremely narrow stability windows.

[0325] 5 Thus, Fig. 37 illustrates an example of a composition of matter, comprising:

[0326] a polymer composition 3700 comprising a plurality of diblock copolymer chains 3702 each comprising a repeating unit 3704 comprising a first block 3706 covalently bonded to a second block 3708, wherein the first block is a polyacrylate and the second block is a polyvinylester, and the polyacrylate and the polyvinylester are 10 microphase separated. The polymer composition can be fractionated, e.g., by chromatography to obtain one or more polymer compositions comprises one or more microphases 3711 comprising at least one of a BCC microphase 3710, a hexagonal microphase 3712, a sigma Frank-Kasper microphase, a gyroidal microphase 3714, a lamellar or layered microphase 3716.

[0327] In one or more embodiments, a microphase comprises a minority phase and a majority phase, the minority phase is disposed as domains 3717 in a matrix 3719 of the majority phase. Either the polyacrylate is the minority phase 3718 and the polyvinylester is the majority phase 3720, or the polyacrylate is the majority phase and the polyvinylester is the minority phase.

[0328] 20 In one example, a BCC microphase can be defined as having a cube unit cell where the minority phase forms spherical domains positioned at the vertices of thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0329] cube and at the center of the cube, and the majority phase as filling the remainder of the cube unit cell / regions between the spherical domains. In one example, a hexagonal microphase can be defined as a hexagon unit cell where the minority phase domains are cylindrical domains positioned at the vertices and center of the hexagon 5 and the majority phase matrix filling the regions between the cylindrical domains. In yet another example, the lamellar microphase can comprise a stack comprising alternating layers of both phases.

[0330] a. Results and Discussion

[0331] 10 Preparation and photoisomerization behavior of diarylethene RAFT agents RAFT agents DEo and DEc (Figure 38a) were synthesized in 11 steps (Supplementary Schemes 1-13) and structurally confirmed by 'H NMR,13C NMR,19F NMR, and HRMS (Figures 41-68).

[0332] In1H NMR measurements (20 mM in CD3CN), DEo was present as a 50:50 15 mixture of its thermodynamic isomers, anti-parallel (DEoap) which undergoes photoisomerization to DEc and parallel (DEoP) which remains non-photoactive50, distinguishable by signals at 8.58 and 8.50 ppm, respectively (Figure 69). This [DEoap] / ([DEoap] + [DEop]) ratio of 0.50 remained constant throughout all photoisomerization experiments. Upon UV irradiation (λ = 302 nm, Intensity = 2.8 mW cm−2), thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0333] isomerization ratio, defined as [DEc] / ([DEc] + [DEoap] + [DEoP]) based on integrals at 8.70 ppm (DEc), 8.58 ppm (DEoap), and 8.50 ppm (DEoP), increased with time to 0.64 after 90 min. (Figure 38b), consistent with the 61% isolated yield obtained under similar conditions (Supplementary Scheme 13). When DEc (20 mM in CD3CN) was 5 irradiated with visible light (λ = 530 nm, Intensity = 56 mW cm−2), [DEc] / ([DEc] + [DEOap] + [DEop]) decreased steadily, and the DEc signal at 8.70 ppm disappeared completely within 35 min (Figure 38c). After irradiation (Figure 70), only DEoapand DEop signals remained in a 50:50 ratio, indicating rapid re-establishment of the thermodynamic equilibrium between the two ring opened isomers.

[0334] 10 UV-vis absorption measurements (0.020 mM in MeCN) demonstrated efficient and reversible photoisomerization between DEo and DEc. Upon UV irradiation (λ = 302 nm, Intensity = 2.8 mW cm−2), DEo rapidly produced the characteristic 556 nm absorption band of DEc within 2 min (Figure 38d). Based on a calibration curve constructed by absorption spectrophotometry (Figure 71), the conversion at the photo-15 stationary state (PSS) was determined to be 0.78 (Figure 72a). Subsequent visible light irradiation (λ = 530 nm, Intensity = 56 mW cm−2) completely removed the 556 nm band within 3 min, yielding a spectrum identical to DEo (Figure 38e). The final absorbancePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0335] at 556 nm was lower than that of pure DEc at the same concentration, owing to spectral overlap with DEo around 300 nm, consistent with the formation of a PSS. In this setup, the PSS (DEc) was slightly higher than in NMR experiments, likely to reflect the lower concentration and absence of inner-filter effects. Kinetic analysis further suggested that 5 the isomerization from DEc to DEo did not proceed linearly (Figure 72b) rather, the rate of change appeared to slow as the concentration of DEc decreased, which may be attributed to factors such as a reduced effective absorption cross-section or altered light penetration at lower concentrations. In both UV-Vis spectra, a clear isosbestic points were observed, supporting the stable photoisomerization between DEo and DEc. 10 Together, NMR and UV-vis data, DEoapand DEoPmixture can be effectively treated as DEo and demonstrate that photoisomerization between DEo and DEc proceeds efficiently and reversibly under the present conditions. The quantitative DEc to DEo conversion is particularly advantageous for practical applications, avoiding complications from isomeric mixtures during separation and purification after polymer 15 synthesis.

[0336] Controlled polymerization using diarylethene RAFT agents

[0337] Before evaluating the selective and controlled polymerization behavior of thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0338] RAFT agents DEo and DEc toward different monomers, their thermal stability and the potential influence of the diarylethene backbone on radical polymerization were investigated. To assess the thermal stability of DEc, a 20 mM solution of DEc was heated in the dark at 75 °C for 24 hours which conditions identical to those used in the 5 subsequent polymerization reactions. Comparison of the1H NMR spectra before and after heating showed no changes, and no signals corresponding to decomposition or isomerization were observed (Figure 73), indicating that DEc is thermally stable under these conditions and does not undergo thermal isomerization to DEo.

[0339] Next, to determine whether the extended conjugation of the ring-closed 10 diarylethene backbone interferes with radical polymerization, free-radical polymerizations of dodecyl acrylate (DDA) in the presence of BocDEo and BocDEc — structurally analogous diarylethenes lacking the RAFT moiety were performed (Supplementary Scheme 14). In these reactions, as well as in a control experiment without any additive, polymerization proceeded similarly. The resulting poly(dodecyl 15 acrylate) (PDDA) exhibited number-average molecular weights (Mn) of 165 kDa, 141 kDa, and 149 kDa, with dispersities (£>) of 3.06, 2.76, and 2.77, respectively (Supplementary Table 1). Furthermore, after purification by precipitation into methanol,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0340] 1H spectra of the resulting polymers revealed no detectable signals derived from the diarylethene backbone in any of the three cases (Figure 74). These results demonstrate that the diarylethene unit does not participate in the acrylate radical polymerization.

[0341] Based on the above results, controlled polymerization of methyl acrylate (MA), 5 a representative MAMs, was conducted using the RAFT agents DEo and DEc (Supplementary Scheme 15, Supplementary Table 2). Conversion profiles (Figure 3a) revealed that polymerization proceeded much faster with DEo than with DEc. The structure of DEo closely resembles that of conventional dithiocarbamates, which are generally less compatible with MA due to their low chain-transfer constants.

[0342] 10 Consequently, propagation dominated over chain transfer, leading to higher-than- expected Mnand broad dispersity. Conversely, DEc incorporates an extended conjugation system through the perfluorocyclopentene moiety in the diarylethene backbone. This is expected to decrease the electron density of the RAFT agent and enhance the chain transfer, accounting for the improved control over acrylate 15 polymerization. When DEo was used, the Mnof poly(m ethyl acrylate) (PMA) remained around 12 kDa regardless of conversion, and D broadened with increasing conversion, reaching 1.92 after 4 h. In contrast, polymerization with DEc showed a linear increasePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0343] in Mnand gradually decreasing D — features associated with controlled radical polymerizations — yielding a significantly narrower D of 1.51 after 4 h (Figure 39b, Supplementary Table 2).

[0344] Next, the control ability of DEo toward vinyl acetate (VAc), a representative 5 LAMs, was investigated (Supplementary Scheme 16, Supplementary Table 3). Since DEo is a dithiocarbamate-type RAFT agent, which matches well with LAMs, it affords well-controlled poly(vinyl acetate) (PVAc). The Mnof PVAc agreed well with theoretical values at each conversion, and D remained as low as 1.37 even after 45 h of reaction, indicating good control (Figure 39c). A clear induction period of ~8 h was 10 observed, and conversion reached 78% at 45 h (Figure 39d). In contrast, polymerization using DEc hardly proceeded even after 45 h. The chain-transfer reactions in DEc were found to be significantly slower. This is likely due to the expected reduction in electron density at the RAFT site caused by its extended conjugation system, which enhances the trapping of the propagating PVAc radical.

[0345] 15

[0346] Quantitative photoisomerization of macro-CTAand block copolymerization Block copolymerization of dodecyl acrylate (DDA, a representative MAMs)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0347] and vinyl acetate (VAc, a representative LAMs) was achieved by sequential polymerization. It has been demonstrated that the miscibility of polyacrylates with PVAc decreases sharply with increasing ester chain bulkiness58. Based on this, the DDA-VAc combination was expected to possess a high segmental interaction 5 parameter (%), leading to microphase separation even at relatively modest molecular weights. First, controlled RAFT polymerization of DDA using DEc as the RAFT agent afforded PDDA with a DEc end group (DEcPDDA) with Mn= 4.7 kDa and D = 1.43 (Supplementary Scheme 17). After purification by methanol precipitation, the ’HNMR spectrum of DEcPDDA exhibited distinct signals corresponding to the DEc moiety 10 (8.75-6.97 ppm), the acrylate unit adjacent to the RAFT chain end (4.73 ppm), and the oxymethylene protons of the dodecyl group (4.01 ppm). The integral ratio of these signals (1:1:20) indicated nearly quantitative chain-end fidelity (Figure 75). UV-Vis analysis (0.01 mM in hexanes) further showed the characteristic absorption band of DEc at 556 nm, and the solution appeared dark purple (Figure 40b, c).

[0348] 15 Upon visible light irradiation (λ = 530 nm, 56 mW cm−2) in hexanes, the purple solution of DEcPDDA became colorless within 2 h (Figure 40d). The UV-Vis spectrum shifted to that of the DEo form (Figure 40b), and 'H NMR confirmed completePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0349] conversion of the DEc signals into those of DEo while maintaining the same integral ratios among the diarylethene moiety, the RAFT end, and the PDDA backbone (Figure 76). GPC traces before and after irradiation were identical, and DOSY NMR analysis showed that the diffusion coefficient (D = 1.47 x 106m2 / s) remained with unchanged 5 fidelity (Figure 40e, Figure 77). These results confirm that quantitative photoisomerization from DEcPDDA to DEoPDDA occurred without detectable side reactions or loss of chain-end.

[0350] The resulting DEoPDDA was then employed as a macro-CTA for the polymerization of VAc (Supplementary Scheme 19). After 23 h, GPC analysis revealed 10 a sharp, unimodal peak at higher molecular weight (Mn= 12.6 kDa, £>= 1.30) compared with the precursor (Figure 40f). The 'H NMR spectrum displayed all major resonances of both PDDA and PVAc blocks, including the characteristic signal of PVAc adjacent to the RAFT end (~6.7 ppm, Figure 78). Although quantitative assessment of chain-end fidelity was hindered by signal broadening at the PDDA-P VAc junction, both GPC and 15 DOSY NMR consistently indicated successful block copolymer formation (PDDA-Z>- PVAc). DOSY NMR showed that all signals of the diarylethene unit, PDDA, and PVAc blocks shared the same diffusion coefficient (D = 6.42 x 107m2 / s) (Figure 79),PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0351] significantly lower than that of the macro-CTA DEoPDDA (D = 1.47 x 106m2 / s), consistent with the formation of higher molecular weight polymers. Furthermore, all fractions obtained by subsequent volume-based separation contained exclusively block copolymers, with no detectable PDDA or PVAc homopolymers. Collectively, these 5 results strongly support the efficient formation of the block copolymer PDDA-Z>-PVAc.

[0352] Chromatographic Fractionation of the unique PDDA-Z>-PVAc diblock copolymer and Observation of Representative Microphase Morphologies

[0353] To construct a diverse library of microphase-separated structures from the 10 unique PDDA-Z>-PVAc diblock copolymer, composed of a MAM and a LAM, chromatographic fractionation was carried out using an automated chromatography system. TLC experiments with eluents ranging from 100% toluene to 100% tetrahydrofuran (THF) identified the appropriate fractionation window as 33-66% THF (Figure 80). The diblock copolymer was dissolved in 33% THF in toluene and directly 15 loaded onto a commercial silica gel column (50 g). The sample was subjected to a linear gradient from 33% THF to 66% THF in toluene over 20 CV at a flow rate of 40 mL / min. The eluent was collected in 22 mL increments, yielding 72 fractions in total with anPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0354] overall recovery of 93% (Figure 81).

[0355] Fractions with similar compositions determined by1H NMR were combined to generate 25 representative library samples of approximately equal mass. The PVAc volume fraction ( / VAC) was calculated from the integral ratio of the methine proton of PVAc (6 5 ~ 5.0 ppm) and the methylene protons of PDDA (6 ~ 4.0 ppm), while molecular weight and dispersity were determined by GPC. These analyses revealed that PDDA-Z>-PVAc Mn = 12.6 kDa, D = 1.30), which originally showed a narrow and symmetric distribution, was fractionated into a broad set of diblock copolymers spanning wide ranges of volume fraction ( / VAC = 0.14-0.64) and molecular weight (Mn = 9.2-16.4 kDa) 10 (Supplementary Table 4, Figure 82,83). The / VAC increased progressively from early to late elution with the increasing polarity of the eluent. The dispersity broadened up to 1.48 in the low- / VAC region but narrowed to 1.20 in the higher- / vAc region, consistent with a dispersity profile dominated by the PDDA block in the broader region and by the PVAc block in the narrower region. Importantly, no homopolymer impurities of 15 PDDA or PVAc were detected in any library sample, confirming successful block copolymerization.

[0356] Using this extensive and high-purity library, SAXS measurements werePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0357] performed to map the self-assembly behavior. Analysis over the compositional range revealed five well-defined microphase-separated morphologies — body-centered cubic spheres (BCC), the low-symmetry Frank-Kasper c phase, hexagonally packed cylinders (HEX), double gyroid (GYR), and alternating lamellae (LAM) with increasing / VAC 5 (Figure 40g). The stabilization of the c phase suggests a high level of conformational asymmetry (E) in the system owing to differences in monomer statistical segment lengths (b Indeed, rheological data yields an estimate of e = bvAelbvo ~ 1.65 which is much higher than the reported e ~ 1.15 threshold for c phase formation59(See Supplementary Information). There is also a narrow window of phase coexistence of 10 HEX and LAM phases between the pure GYR and LAM phases; such behavior has previously been reported in analogous conformationally-asymmetric systems60. Notably, the high phase-space resolution afforded by chromatographic fractionation enabled the identification of these phases with extremely narrow windows of stability (~3% / VAC), which are often missed through iterative approaches. The phase diagram of 15 this system (Figure 40h, Supplementary Table 6) was constructed using / derived through random-phase analysis (Figure 84, 85). Variable-temperature SAXS was used to approximate the order-disorder transition temperature (TODT) after heating in 10 °CPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0358] increments (We note that TODT for LAM were thermally inaccessible, and the %NODT boundary is an approximation). Importantly, the high conformational asymmetry skews the phase diagram from the symmetric case, shifting phase transitions to higher / VAC in close agreement with self-consi stent field theory (SCFT) predictions for such systems.

[0359] 5 Together, these results highlight the power of fractionation-driven libraries not only to expand the accessible phase space but also to enable rigorous comparison with theoretical phase diagrams.

[0360] Fig. 40g shows that for the diblock copolymer synthesized in this example, the minority phase having a volume fraction in a range of 14%-26% results in a 10 polymer composition having a body center cubic (BCC) microphase structure; a sigma Frank Kasper micro phase structure emerges for the minority phase having a volume fraction in a range of 27%-29%; the minority phase having a volume fraction in a range of 30%-40% results in the polymer composition having a hexagonal microphase structure; the polymer composition forms a gyroidal microphase structure at around 41% minority phase volume fraction; a hexagonal and lamellar coexistence region in the polymer composition appears at around 43% minority phase volume fraction; and a volume fraction in a range of 46% - 65% results in the polymer composition having a lamellar (layered) microphase structure.

[0361] As used herein, minority phase volume fraction = minority phase 20 volume / total volume of the polymer composition, where the total volume is volume ofPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0362] both the minority phase and the majority phase in the polymer composition. The volume fraction can be represented as a percentage by multiplying by 100. For the experiments presented herein, in some fractions, the minority phase is polyacrylate in the majority phase of polyvinylester. In some other fractions the minority phase is 5 polyvinylester in a polyacrylate majority phase matrix.

[0363] Further analysis of the SAXS data in Figure 40g shows that the minority phase forms domains embedded or within the majority phase matrix, and adjacent ones of the domains have a center-to-center distance d ~ 14 nanometers (see labeling of d in Figure 37) for BCC; d ~13 nm for the sigma phase; d ~10 to 11 nm for the 10 hexagonal phase; and d 1 to 12 nm for the gyroidal phase. For the lamellar phase, the SAXS data yields d ~16 nm separating centers of two adjacent layers of the same phase (with the other phase in between). More generally adjacent ones of the domains / phases have a center-to-center distance d in a range of 10 nm-100 nm. The center-to-center distance d is measured between the center of one domain / phase and the center of the adjacent / next neighboring domain / phase of the same type.

[0364] For the example synthesized here, the experiments show that a minority phase volume fraction of at least 14% is required for ordered microphase separation (or that if the minority phase volume fraction is less than 14%, the microphase separation is disordered, as evidenced by no peaks or patterns being visible in the 20 SAXS). In Figure 40h, the ordering of phases from BCC to lamellar as a function of volume fraction is expected to repeat as the minority phase changes from polyvinylester to polyacrylate.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0365] Fig. 40h shows that the polyacrylate and polyvinylester phases are miscible when the calculated segmental interaction parameter (%N) is 25 or less, where N is the number of repeating units in the copolymer (total degree of polymerization (number of segments in the copolymer)). Typically, miscibility can be improved by tuning the 5 length of the alkyl side chain in the polyacrylate. In one or more embodiments, the polyacrylate comprises an alkyl side chain with more than one carbon atom (e.g., polyethylacrylate, polypropylacrylate, polybutylacrylate, polypentylacrylate, polyhexylacrylate, polyheptylacrylate, etc.). In one or more embodiments, the polyacrylate comprises one or more alkyl side chains with more than four carbon 10 atoms in each side chain. In one or more embodiments, the alkyl side-chain in the polyacrylate is in a range of 2-30 carbon atoms).

[0366] % was calculated by determining the parameters A and B from the fitting shown in Figure 84 using the relation % = A / T + B, and then substituting into this equation the temperatures at which miscibility was observed in the actual SAXS measurements, the details of which are described on page 86.

[0367] The volume fraction of the two phases in the polymer composition can be tuned for various applications. For example, a polymer composition having a lamellar microphase structure may be useful as a lithographic material (e.g., photoresist), a packaging material (e.g., for electronics) that acts as a moisture and / or oxygen barrier.

[0368] 20 In another example, a polymer composition having a hexagonal microphase structure may be useful as a gas separation membrane (e.g., for separating gases such as, but not limited to, oxygen). In yet another example, a polymer composition having aPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0369] sigma phase may be useful as modifier. In yet a further example, the polymer composition having a BCC microphase may be useful for plastic molding or as a filler, or for drug delivery.

[0370] 5 8. Supplementary Information for Example 7 (Mapping of phase separation).

[0371] a. General methods

[0372] (i) Materials

[0373] Unless otherwise noted, all chemicals were purchased from commercial suppliers and used without further purification. The following reagents were obtained 10 from the indicated suppliers:

[0374] 6-bromobenzo[b]thiophene (Ambeed, Inc.); copper(I) iodide (Cui, Sigma-Aldrich Co. LLC); methylamine 40% aqueous solution (MeNBL aq., Sigma-Aldrich Co. LLC); di- / c / V-butyl dicarbonate (BOC2O, Neta Scientific Inc.); sodium iodide (Nal, Fisher Scientific International, Inc.); imidazole (Fisher Scientific International, Inc.); n-15 butyllithium, 2.0 M solution in cyclohexane (w-BuLi, Sigma-Aldrich Co. LLC); iodine (L, Sigma-Aldrich Co. LLC); isopropylmagnesium chloride, 2.0 M solution in THF (z'PrMgCl, Sigma-Aldrich Co. LLC); zinc (II) chloride (ZnCL, Sigma-Aldrich Co. LLC); [1,1 '-diphenylphosphinoferrocene]dichloropalladium (II) • di chloromethanePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0375] complex (PdC12(dppf) DCM, Sigma-Aldrich Co. LLC); A-bromosuccinimide (NBS, Tokyo Chemical Industry Co., Ltd.); octafluorocyclopentene (CsFs, Tokyo Chemical Industry Co., Ltd.); 2,4-dimethylthiophene (Ambeed, Inc.); pyridine-4-boronic acid (Neta Scientific Inc.); tetrakis(triphenylphosphine)palladium (0) (Pd(PPhs)4, Ambeed, 5 Inc.); potassium carbonate (K2CO3, Fisher Scientific International, Inc.); 1,4-di oxane (Fisher Scientific International, Inc.); carbon disulfide (CS2, Fisher Scientific International, Inc.); sodium hydroxide (NaOH, Fisher Scientific International, Inc.); methyl 2-bromopropionate (Sigma-Aldrich Co. LLC); magnesium sulfate (MgSCL, Fisher Scientific International, Inc.). Tetrahydrofuran (THF), acetonitrile (MeCN), 10 hexanes, ethyl acetate (AcOEt), dichloromethane (DCM), 1,4-dioxane, diethyl ether (Et2O), methanol (MeOH), and toluene were purchased from Fisher Scientific International, Inc. 2,2,2-trifluoroethanol (TFE) was purchased from Sigma- Aldrich Co. LLC. 2,2'-Azobis(2-methylpropionitrile) (AIBN, Sigma-Aldrich Co. LLC) was recrystallized from methanol prior to use. l,l'-Azobis(cy cl ohexane-1 -carbonitrile) (V-15 40, Sigma-Aldrich Co. LLC) was used as received. Vinyl acetate (VAc), methyl acrylate (MA), styrene (St), and dodecyl acrylate (DDA) were purchased from Tokyo Chemical Industry Co., Ltd. All monomers were purified prior to use by passagePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0376] through a column packed with alumina (standard grade, Brockmann I, activated, basic) to remove inhibitors.

[0377] (ii) Characterization

[0378] 5 NMR spectra were recorded on a Bruker Avance III HD (400 MHz), a Bruker Avance NEO (500 MHz), or a Varian Unity Inova AS600 (600MHz) spectrometer, and analyzed by MestReNova. Chemical shifts (8) are reported in ppm and calibrated using residual undeuterated solvent as an internal reference (CHCh @ 7.26 ppm 'H NMR, 77.02 ppm13C NMR, DMSO4 @ 2.49 ppm 'H NMR, 40.00 ppm13C NMR, CD3CN 10 @ 1.94 ppm 'H NMR). The following abbreviations (or combinations thereof) were used to explain the multiplicities: s = singlet, d = doublet, dd = doublet of doublets, t = triplet, q = quartet, qd = quartet of doublets, m = multiplet, br = broad. Size-exclusion chromatography (SEC) was performed on a Waters instrument using a differential refractive index detector and two Tosoh columns (TSKgel SuperHZM-N, 3 pm 15 polymer, 150 x 4.6 mm) with chloroform containing 0.25% triethylamine at 35 °C for the mobile phase. Molar masses and molar mass dispersities (£)) were determined against narrow polystyrene standards (Agilent). Ultraviolet-visible spectroscopy (UV-PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0379] vis) was conducted on a Shimadzu UV3600 UV-Nir-NIR Spectrometer. Photoisomerization experiments were achieved via a UVP Ultra-violet products Handy UV lamp (1 = 302 nm, Intensity = 2.8 mW / cm2) and THORLABS COP1-A M530L3-C1 LED light (1 = 530 nm, Intensity = 56 mW / cm2). Flash column chromatography was 5 performed with Biotage Isolera or Selekt. High resolution mass spectroscopy (HRMS) was obtained from the UC Santa Barbara Mass Spectrometry Facility on time-of-flight mass spectrometers with ESI and GCMS sources. SAXS measurements were collected on a custom-built high brilliance laboratory beamline for small and wide-angle X-ray scattering (SAXS / WAXS) hosted by the BioPACIFIC Materials Innovation Platform 10 at UC Santa Barbara. The instrument consists of a high brightness liquid metal jet X- ray source (Excillum D2+ 70 kV), a low-background scatterless slit beam collimation system (developed in-house), and a 4-megapixel hybrid photon counting area detector (Dectris Eiger2 R 4M) housed in a 3 meter vacuum vessel. 2-D data were reduced to a 1-D form of intensity (arbitrary units) as a function of the magnitude of the wave vector 15 q = \q\ = 4TI sin(3 / 2) / A, where 6 is the scattering angle and 2 is the X-ray wavelength.

[0380] Samples were prepared by pressing 10-15 mg of bulk polymer within a Kapton tape- backed metal washer and sealing with more Kapton tape. Samples were annealed underPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0381] vacuum (-200 mTorr) at 150 °C for 30 minutes followed by extended annealing at

[0382] 75 °C for 12 hours. Samples were slowly cooled under vacuum to room temperature

[0383] prior to testing. For S03, which formed the o phase, an extended annealing time of 7

[0384] days at 120 °C was used owing to the slow kinetics of Frank-Kasper phase formation,

[0385] 5 and the sample was transferred and tested at this elevated temperature. Variable¬

[0386] temperature measurements were done using a custom-built sample holder and heating

[0387] system. Samples were heated to the target temperature and isothermally held for 5

[0388] minutes to allow for temperature equilibration. SAXS was used to approximate the

[0389] order-disorder transition temperature (TODT) by heating in 10 °C increments, with the

[0390] 10 TODT taken as the highest temperature where an ordered morphology was observed.

[0391] (iii) Synthesis and characterization of diarylethene RAFT agents

[0392] Preparation of MeNBT (Supplementary Scheme 1)

[0393] reflux, 24 h

[0394]

[0395] H MeNBT (83% yield.)

[0396] Supplementary Scheme 1. Preparation of (MeNBT).PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0397] A 150 mL high-pressure sealed round botom flask equipped with a stir bar was charged with 6-bromobenzo[b]thiophene (12.8 g, 60 mmol), copper(I) iodide (Cui, 571 mg, 3.0 mmol), and 40% aqueous methylamine solution (25 mL, ca. 300 mmol). The mixture was refluxed at 110 °C under argon atmosphere for 24 h. After cooling to 5 room temperature, the mixture was diluted with 100 mL of water and extracted with diethyl ether. The combined organic layers were washed with brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate (0 to 20%) to afford MeNBT as a pale yellow liquid (8,17 g, 83% 10 yield).

[0398] 'HNMR (400 MHz, CDCh) 67.59 (d, J= 8.6 Hz, 1H), 7.18 (dd, J= 5.4, 0.8 Hz, 1H), 7.10 (d, J= 5.4 Hz, 1H), 7.04 (d, J= 2.2 Hz, 1H), 6.71 (dd, J= 8.6, 2.2 Hz, 1H), 3.79 (s, 1H), 2.90 (s, 3H).

[0399] 1513CNMR (101 MHz, CDCh) 6 146.89, 141.94, 131.34, 123.81, 123.44, 121.22, 113.30, 102.84, 30.98. HRMS (ESI+): m / z Calcd. for C9H10NS ([M+H]+): 164.0534; Found: 164.0530.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0400] Preparation of BocBT (Supplementary Scheme 2)

[0401] BOC2O, Nal

[0402] THF, r.t., 16 h

[0403]

[0404] MeNBT BocBT (quant)

[0405] 5 Supplementary Scheme 2. Preparation of BocBT.

[0406] A 200 mL round bottom flask equipped with a stir bar was charged with MeNBT (8.00 g, 49 mmol), sodium iodide (7.35 g, 49 mmol) and THF (80 mL). BOC2O (12.8 g, 59 mmol) was added at once to the mixture with stirring on ice bath. The mixture was 10 stirred at room temperature for 16 h. After the reaction, imidazole (680 mg, 10 mmol) was added and stirred for 1 h to quench an excess of BOC2O. After evaporation, the mixture was poured into 100 mL of 0.1 M HC1 aq. and extracted with diethyl ether. The combined organic layers were washed with sat. NaHCCh aq., and brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure. The crude 15 residue was purified by silica gel column chromatography using a gradient ofPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0407] hexanes / ethyl acetate (0 to 10%) to afford BocBT as a white solid (12,9 g, quant.).

[0408] 'H NMR (400 MHz, CDCh) 67.80 - 7.68 (m, 2H), 7.41 (d, J= 5.5 Hz, 1H), 7.30 (dd, J= 5.5, 0.8 Hz, 1H), 7.28 - 7.22 (m, overlaps with CHCh), 3.32 (s, 3H), 1.45 (s, 9H).

[0409] 513C NMR (101 MHz, CDCh) 6 154.94, 140.55, 139.85, 137.23, 126.45, 123.45, 123.28,

[0410] 122.97, 119.20, 80.35, 37.78, 28.35.

[0411] HRMS (ESI+): m / z Calcd. for CwHisNChS ([M+H]+): 286.0877; Found: 286.0868.

[0412] Preparation of IBocBT (Supplementary Scheme 3)

[0413] 10

[0414] 1) n-BuLi, -78 □, 1 h 2) I2, “78 > 1 h THF

[0415]

[0416] BocBT IBocBT (85% yield.) Supplementary Scheme 3. Preparation of IBocBT.

[0417] A flame dried 200 mL Schlenk flask equipped with a stir bar was charged with BocBT

[0418] 15 (7.90 g, 30 mmol) and dry THF (150 mL) was stirred on dry ice methanol bath (-78 °C)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0419] for 15 min under argon atmosphere. w-BuLi (2.0 M in cyclohexane solution, 16.1 mL, 32 mmol) dropped slowly into the solution for 15 min. The mixture was stirred at -78 °C for Ih. Iodine tips (8.15 g, 32 mmol) were added at once. The reaction mixture was stirred for 1 h with slowly warmed up to room temperature. The reaction was 5 quenched by 20 mL of 10% Na2SOs aq. and extracted with diethyl ether. The combined organic layers were washed with 10% Na2SOs aq., water and brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography using a gradient of hexane s / ethyl acetate (0 to 10%) to afford IBocBT as a pale yellow crystalline solid.

[0420] 10 (9,87 g, 85% yield.)

[0421] 'H NMR (400 MHz, CDCh) 67.65 - 7.62 (m, 2H), 7.48 (d, J= 0.7 Hz, IH), 7.20 (dd, J= 8.5, 2.0 Hz, IH), 3.30 (s, 3H), 1.45 (s, 9H).

[0422] 13C NMR (101 MHz, CDCh) 6 154.76, 144.42, 140.68, 138.40, 133.34, 123.09, 121.92, 15 117.91, 80.53, 77.86, 37.65, 28.33.

[0423] HR MS (ESI): m / z Calcd. for C14H16INO2S ([M+Na]+): 411.9844; Found: 411.9847.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0424] Preparation of zPrBocBT (Supplementary Scheme 4)

[0425] ZnCI2 / PrMgCI - ► / PrZnCI THF, 0 °C, to r.t., 1 h

[0426]

[0427] BocBT zPrBocBT (93% yield.) Supplementary Scheme 4. Preparation of zPrBocBT.

[0428] 5

[0429] 1) Preparation of isopropyl zinc chloride THF solution.

[0430] Zinc chloride was charged to 50 mL round bottom flask equipped with alkali cold traps and flame heated under vacuum to melt to afford anhydrous salt. Theanhydrous zinc chloride (5.11 g, 37.5 mmol) and dry THF (37.5 mL) were charged to a new flame dried 10 Schlenk flask equipped with a stir bar. Isopropylmagnesium chloride THF solution (zPrMgCl) (2.0 M, 18.8 mL, 37.5 mmol) was dropped into mixture at 0 °C under argon atmosphere. Then mixture was stirred for 1 h and slowly warmed up to room temperature to afford isopropyl zinc chloride THF solution.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0431] 2) Negishi cross coupling with IBocBT,

[0432] IBocBT (9.73 g, 25 mmol) and [l,l’-bis(diphenylphosphino)ferrocene] dichloropalladium (II) dichloromethane complex (PdC12(dppf)DCM) (102 mg, 0.13 mmol) were added into the Schlenk flask charged with the alkyl zinc agent with argon 5 flush. The mixture was stirred continuously for 1.5 h at 50 °C. After the reaction, the mixture was slowly poured into sat. NH4CI aq. and extracted with diethyl ether. The combined organic layers were washed with water and brine, dried over anhydrous MgSC>4, filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate 10 (0 to 10%) to afford z'PrBocBT as a white solid (7.12g, 93% yield.).

[0433] 'H NMR (400 MHz, CDCh) 67.59 (d, J= 8.5 Hz, 2H), 7.17 (dd, J= 8.5, 2.0 Hz, 1H), 6.97 (s, 1H), 3.29 (s, 3H), 3.28 - 3.17 (hept, J= 6.9 Hz, 1H), 1.44 (s, 9H), 1.39 (d, J = 6.9 Hz, 6H).

[0434] 1513C NMR (101 MHz, CDC13) 6 155.02, 154.36, 139.76, 138.89, 137.77, 122.83, 122.52, 119.11, 117.81, 80.18, 37.83, 30.59, 28.36, 24.34.

[0435] HR MS (ESI): m / z Calcd. for C17H23NO2S ([M+Na]+): 328.1347; Found: 328.1349.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0436] Preparation of zPrBrBocBT (Supplementary Scheme 5)

[0437] Br

[0438]

[0439] / PrBocBT zPrBrBocBT (93% yield.) 5 Supplementary Scheme 5. Preparation of zPrBrBocBT.

[0440] A 50 mL round bottom flask charged with zPrBocBT (7.03 g, 23 mmol), and MeCN

[0441] (46 mL) was stirred on ice bath. A-bromosuccinimide (NBS) (4.13 g, 23.2 mmol) was

[0442] slowly added. After addition, the mixture was stirred at room temperature for 30 min.

[0443] 10 After the reaction, the mixture was poured into water and extracted with ethyl acetate.

[0444] The combined organic layers were washed with water and brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure. The crude residue was

[0445] purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate

[0446] (0 to 10%) to afford zPrBrBocBT as a yellow sticky oil (8,19 g, 93% yield).

[0447] 15PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0448] 'H NMR (400 MHz, CDCh) 67.67 (d, J= 8.6 Hz, 1H), 7.62 (d, J= 1.9 Hz, 1H), 7.28 (dd, J = 8.6, 2.0 Hz, 1H), 3.54 (hept, J= 6.9 Hz, 1H), 3.30 (s, 3H), 1.44 (s, 9H), 1.36

[0449] (d, <7= 6.9 Hz, 6H).

[0450] 13C NMR (101 MHZ, CDCh) 6 154.84, 148.07, 140.99, 136.43, 136.02, 123.53, 122.33, 5 119.27, 103.59, 80.48, 37.78, 30.38, 28.37, 23.47.

[0451] HR MS (ESI): m / z Calcd. for C14H16INO2 ([M+Na]+): 406.0452; Found: 406.0456.

[0452] Preparation of BocBTFCp (Supplementary Scheme 6)

[0453] / 'PrBrBocBT BocBTFCp (56% yield.)

[0454]

[0455] Supplementary Scheme 6. Preparation of BocBTFCp.

[0456] A flame dried 200 mL Schlenk flask equipped with a stir bar was charged with zPrBrBocBT (5.50 g, 14 mmol) and dry THF (70 mL) was stirred in dry ice methanolPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0457] bath (-78 °C) for 10 min under argon atmosphere. / r-BuLi (2.0 M in cyclohexane, 7.5 mL, 15 mmol) was dropped slowly into the solution. The mixture was stirred at -78 °C for 40 min. Octafluorocyclopentene (CsFs) (2.0 mL, 15mmol) was added at once and after stirred for 24 h with keeping the temperature. After the reaction, the mixture was 5 slowly poured into sat. NH4Q aq. and extracted with diethyl ether. The combined organic layers were washed with water and brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate (0 to 10%). After drying, the residue was recrystallized from hexanes and dried under reduced pressure 10 to afford BocBTFCp as a colorless oil(3,98 g, 56% yield).

[0458] 'H NMR (400 MHz, CDCh) 67.69 (d, J= 2.1 Hz, 1H), 7.38 (d, J= 8.6 Hz, 1H), 7.27 (d, J= 10.7 Hz, 1H overlaps with CHCh), 3.31 (s, 3H), 3.12 (hept, J= 7.4 Hz, 1H), 1.46 (s, 9H), 1.37 (d, J= 6.8 Hz, 6H).

[0459] 1513C NMR (101 MHz, CDCh) 6 157.76, 154.76, 141.02, 137.97, 135.37, 123.63, 121.46, 121.44, 119.25, 111.25, 80.64, 37.69, 30.22, 28.36, 25.07.

[0460] 19F NMR (376 MHz, CDCh) 8 -108.13 (d, J = 166.0 Hz, 2F), -118.90 (t, J = 11.5 Hz,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0461] 2F), -125.25 - -125.33 (m, IF), -130.22 (d, J= 36.4 Hz, 2F).

[0462] HRMS (ESI+): m / z Calcd. for C22H22F7NO2S ([M+Na]+): 520.1170; Found: 520.1145.

[0463] Preparation of BrTh (Supplementary Scheme 7)

[0464] 5

[0465] NBS

[0466]

[0467] MeCN, 0 °C to r.t., 3 h.

[0468] BrT (97% yield.) Supplementary Scheme 7. Preparation of BrTh.

[0469] A 200 mL round bottom flask charged with 2,4-dimethylthiophene (3.37 g, 30 mmol) 10 and acetonitrile (100 mL) was stirred in ice bath for 10 min. NBS (10.70 g, 60.1 mmol) was slowly added. After that, ice bath was removed, and the mixture was stirred for 2 h. After the reaction, the mixture was poured into water and extracted with hexanes three times and combined organic layer was washed with water and brine, dried over MgSO4. After filtration, solvent was evaporated under reduced pressure. The residuePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0470] was through the short path silica gel column with hexanes to afford 2,4-dibromo-3,5- dimethylthiophene (BrTh) as a colourless oil (1.78 g, 97% yield).

[0471] 'H NMR (400 MHz, CDCh) 62.34 (s, 1H), 2.17 (s, 1H).

[0472] 513C NMR (101 MHz, CDCh) 6 136.26, 133.90, 111.38, 104.71, 16.12, 15.39.

[0473] GC TOF MS (El): m / z Calcd. for C6H6Br2S ([M]+): 267.8557; Found: 267.8566.

[0474] Preparation of BrThPy (Supplementary Scheme 8)

[0475] pyridine-4-boronic acid Pd(PPh3)4> K2CO3dioxane, 90 °C, 24 h.

[0476] BrThPy (72% yield.)

[0477]

[0478] Supplementary Scheme 8. Preparation of BrThPy.

[0479] A 100 mL round bottom flask charged with argon, potassium carbonate (2.07 g 15 mmol), tetrakis(triphenylphosphine)palladium (173 mg, 0.15 mmol), pyridine-4-15 boronic acid (615 mg, 5.0 mmol) and 2,4-dibromo-3,5-dimethylthiophene (1.35 g, 5.0PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0480] mmol) was suspended 1,4-dioxane (20 mL) and water (5 mL). The reaction mixture was stirred at 90 °C for 16 h. After the reaction, the mixture was poured into water and extracted with diethyl ether. The combined organic layers were washed with water and brine, dried over anhydrous MgSCL, filtered, and concentrated under reduced pressure.

[0481] 5 The crude residue was purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate (0 to 35%) to afford BrThPy as a light yellow powder(968,2 mg, 72% yield).

[0482] 'HNMR (400 MHz, CDCh) 6 8.66 - 8.60 (m, 1H), 7.34 - 7.28 (m, 1H), 2.45 (s, 1H), 10 2.33 (s, 2H).

[0483] 13C NMR (101 MHz, CDCh) 6 150.14, 142.11, 134.68, 134.57, 131.58, 122.95, 114.63, 15.90, 15.39.

[0484] HR MS (ESI): m / z Calcd. for C11H10BrNS ([M+H]+): 267.9796; Found: 267.9785.

[0485] 15 Preparation of BocDEo (Supplementary Scheme 9) (Fig, 86)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0486] BocBTFCp THF, -78 ° ’, 24 h

[0487]

[0488] BrThPy

[0489] Supplementary Scheme 9. Preparation of BocDEo.

[0490] A flame dried 100 mL Schlenk flask equipped with a stir bar was charged with BrThPy

[0491] 5 (1.37 g, 5.1 mmol) and dry THF (25 mL) was stirred on dry ice methanol bath (-78 °C)

[0492] for 10 min under argon atmosphere. w-BuLi (2.0 M in cyclohexane, 2.7 mL, 5.4 mmol)

[0493] was dropped slowly into the solution. The mixture was stirred at -78 °C for 1 h. 25 mL

[0494] THF solution of BocBTFCp (2.55 g, 5.1 mmol) was dropped and stirred for 24 h with

[0495] keeping that temperature. After the reaction, the mixture was slowly poured into sat.

[0496] 10 NH4Q aq. and extracted with diethyl ether. The combined organic layers were washed

[0497] with water and brine, dried over anhydrous MgSCL, filtered, and concentrated under

[0498] reduced pressure. The crude residue was purified by silica gel column chromatography

[0499] using a gradient of hexanes / ethyl acetate (0 to 25%) to afford BocDEo as slightly

[0500] yellow solid (2,84 g 83% yield). The ratio of anti-parallel(ap) and parallel(p) isomer inPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0501] DMSO- is was 55 / 45.

[0502] 'HNMR (500 MHz, DMSO-fifc) 6 8.62 - 8.61 (m, 1.1H, ap), 8.53 - 8.51 (m, 0.9H, p), 7.92 (dd, J= 5.2, 2.0 Hz, 1H, ap and p), 7.58 (d, J= 9.0 Hz, 0.55H, ap), 7.54 (dd, J = 5 8.8, 1.8 Hz, 0.45H, p), 7.43 - 7.38 (m, 2.1H, ap and p), 7.24 - 7.22 (m, 0.9H, p), 3.23 (d, J= 8.9 Hz, 3H, ap and p), 3.01 (ddd, J= 26.8, 13.5, 6.7 Hz, 1H, ap and p), 2.51 (s, 1.35H, p), 2.29 (d, J= 2.8 Hz, 1.65H, ap), 2.08 (s, 1.65H, ap), 1.92 (s, 1.35H, p), 1.37 (d, J= 17.3 Hz, 9H, ap and p), 1.27 (dd, J= 16.2, 6.7 Hz, 3H, ap and p), 1.07 (d, J = 6.7 Hz, 1.35H, p), 0.96 (d, J= 6.7 Hz, 1.65H, ap).

[0503] 1013C NMR (126 MHz, DMSO-fifc) 6 157.13, 156.69, 154.19, 150.65, 150.54, 141.99, 141.73, 141.16, 140.92, 140.65, 137.73, 137.65, 134.79, 134.64, 134.39, 133.62, 133.50, 125.95, 125.93, 124.33, 123.21, 122.99, 122.27, 119.82, 119.79, 115.61, 80.27, 80.22, 37.63, 37.58, 29.99, 29.92, 28.32, 28.26, 26.15, 25.98, 24.79, 24.60, 15.08, 15.00, 14.94, 14.83.

[0504] 1519F NMR (376 MHz, DMSO-fifc) 6 -107.56 - -111.83 (m, 4F), -131.13 - -133.20 (m, 2F).

[0505] HR MS (ESI): m / z Calcd. for C33H32F6N2O2S2 ([M+H]+): 667.1888; Found: 667.1891.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0506] Preparation of BocDEc (Supplementary Scheme 10) (fig. 87)

[0507]

[0508] 5 Supplementary Scheme 10. Preparation of BocDEc.

[0509] A 1.5 mL quartz cell (path length 5 mm) equipped with a stir bar charged with BocDEo (25.2 mg) and acetone (1.5 mL). The reaction mixture was stirred at room temperature with irradiating UV (1 = 302 nm) for 1.5 h. After concentration, the crude residue was 10 purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate (0 to 11%) to afford BocDEc as a dark purple solid (12,1 mg, 48% yield).

[0510] 'H NMR (500 MHz, DMSO-tL) 68.75 - 8.73 (m, 2H), 7.66 (dd, J= 8.9, 2.1 Hz, 1H), 7.53 - 7.52 (m, 2H), 7.42 (d, J= 2.2 Hz, 1H), 7.21 (dd, J= 8.9, 2.2 Hz, 1H), 3.22-3.17 15 (m, 4H), 2.14 (s, 3H), 2.02 (dd, J= 3.5, 1.5 Hz, 3H), 1.44 (s, 9H), 1.10 (dd, J= 9.4, 6.7PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0511] Hz, 6H).

[0512] 13C NMR (126 MHz, DMSO-fifc) 6 156.97, 154.63, 153.57, 150.72, 148.35, 147.14, 142.59, 141.46, 128.49, 126.13, 126.13 123.21, 122.66, 118.43, 81.19, 72.30, 64.61, 38.09, 36.75, 29.00, 28.25, 22.47, 20.79, 14.73, 14.67.

[0513] 519F NMR (376 MHz, DMSO) 6 -101.69 (d, J= 262.9 Hz, IF), -103.06 (d, J= 261.6 Hz, IF), -106.74 (d, J= 254.1 Hz, IF), -117.38 (d, J= 254.1 Hz, IF), -131.26 (d, J = 247.3 Hz, IF), -132.35 (d, J= 241.1 Hz, IF).

[0514] HR MS (ESI): m / z Calcd. for C33H32F6N2O2S2 ([M+H]+): 667.1888; Found: 667.1890.

[0515] 10 Preparation of MeNDE (Supplementary Scheme 11) (Fig, 88)

[0516]

[0517] Supplementary Scheme 11. Preparation of MeNDE.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0518] A 50 mL round bottom flask charged with BocDEo (2.00 g, 3.0 mmol). 12.5 mL of cone. HC1 aq. (ca. 150 mmol) was slowly added. The reaction mixture was stirred at room temperature for 10 min. After the reaction, the homogenous solution was neutralized by NaOH aq. resulting in the formation of a precipitate that was collected 5 by filtration, washed with water, and dried under reduced pressure to afford MeNDE as yellow soild (1.67 g, 98% yield).

[0519] 'H NMR (400 MHz, DMSO-tL) 6 8.67 - 8.66 (m, 1.05H, ap), 8.59 - 8.57 (m, 0.95H, p), 7.58 - 7.57 (m, 1.05H, ap), 7.44 - 7.42 (m, 0.95H, p), 7.30 (td, J= 8.7, 2.1 Hz, 1H, 10 ap and p), 6.94 (dd, J = 4.0, 2.1 Hz, 1H, ap and p), 6.77 (ddd, J = 8.8, 4.8, 2.2 Hz, 1H, ap and p), 2.88 (dh, J= 13.4, 6.7 Hz, 1H, ap and p), 2.69 (d, J= 4.8 Hz, 3H, ap and p), 2.51 (d, J= 1.7 Hz, 1.43H, p), 2.29 (d, J= 3.0 Hz, 1.57H, ap), 2.08 (s, 1.57H, ap), 1.92 (s, 1.43H, p), 1.20 (dd, J= 11.5, 6.7 Hz, 3H, ap and p), 0.97 (d, J= 6.7 Hz, 1.43H, p), 0.87 (d, J = 6.7 Hz, 1.57H, ap).

[0520] 1513C NMR (101 MHz, DMSO-tL) 6 150.36, 149.89, 148.46, 148.03, 147.95, 143.25, 142.85, 139.93, 139.86, 136.04, 135.73, 132.78, 132.64, 127.69, 127.61, 126.63, 126.51, 123.76, 123.72, 122.91, 115.65, 114.01, 102.80, 30.51, 30.47, 29.58, 29.55,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0521] 26.11, 25.99, 24.75, 24.59, 15.30, 15.23, 15.19, 14.93.

[0522] 19F NMR (376 MHz, DMSO) 6 -107.35 - -111.87 (m, 4F), -131.17 - -133.18 (m, 2F).

[0523] HR MS (ESI): m / z Calcd. for C28H24F6N2S2 ([M+H]+): 567.1363; Found: 567.1368.

[0524] 5 Preparation of DEo (Supplementary Scheme 12) (fig, 89)

[0525] 1) CS2. NaOH, THF / water, r t, 16 2) methyl-2-bromopropionate, Acetone, r t, 1 h

[0526]

[0527] Supplementary Scheme 12. Preparation of DEo.

[0528] 10 A 40 mL round bottom flask equipped with a stir bar charged with MeNDE (891 mg,

[0529] 1.60 mmol), THF (1.6 mL) and water (1.6mL). NaOH (512 mg, 13 mmol) was added and dissolved completely. Carbon disulfide (CS2, 773 pL, 13 mmol) was then added and the resulting mixture was vigorously stirred at room temperature for 16 h. After the reaction, mixture was diluted with acetone and filtered. The filtrate was concentrated 15 under reduced pressure and resulting residue was washed with diethyl ether to affordPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0530] the dithiocarbamate sodium salt. This was used directly in the next step without further purification. The dithiocarbamate sodium salt was charged to a 40 mL round bottom flask equipped with a stir bar and dissolved into acetone (3mL). methyl-2- bromopropionate (200 pL, 1.7 mmol) was added and stirred at room temperature for 1 5 h. After evaporation, the crude residue was purified by silica gel column chromatography using a gradient of hexane s / ethyl acetate (0 to 25%) to afford DEo as slightly yellow solid (989 mg, 85% yield). The ratio of anti-parallel(ap) and parallel(p) isomer in DMSO-t / r, was 55 / 45.

[0531] 10 'HNMR (400 MHz, DMSO) 8 8.61 - 8.59 (m, 1.08H, ap), 8.51 - 8.49 (m, 0.92H, p), 8.16 - 8.10 (m, 1H, ap and p), 7.78 - 7.69 (m, 1H, ap and p), 7.70 (d, J= 8.6 Hz, 1H), 7.46 - 7.40 (m, 2.08H ap and p), 7.23 (d, J= 5.2 Hz, 0.92H, p), 4.49 (q, J= 7.5 Hz, 1H, ap and p), 3.69 (d, J= 4.3 Hz, 3H, ap and p), 3.59 (d, J= 9.0 Hz, 3H, ap and p), 3.09 - 2.96 (m, 1H, ap and p), 2.51 (s, 1.35H, p), 2.28 (d, J = 2.9 Hz, 1.65H, ap), 2.06 (s, 15 1.65H, ap), 1.89 (d, J= 1.9 Hz, 1.35H, p), 1.38 (d, J= 7.6 Hz, 3H, ap and p), 1.27 (dd, J= 14.5, 6.7 Hz, 3H, ap andp), 1.08 (dd, J=6.7, 1.9 Hz, 1.35H, p), 0.95 (d, = 6.7Hz, 1.65H, ap).PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0532] 13C NMR (126 MHz, DMSO) 6196.21, 172.17, 172.14, 172.13, 159.77, 159.41, 150.63, 150.61, 150.53, 142.14, 141.88, 140.93, 140.66, 138.16, 138.06, 137.57, 134.42, 134.37, 133.73, 133.59, 125.80, 124.75, 123.82, 123.25, 123.21, 123.01, 122.49, 115.82, 115.76, 52.93, 52.90, 49.54, 49.52, 49.49, 49.45, 46.57, 30.15, 30.08, 26.13, 5 25.96, 24.81, 24.56, 17.53, 17.51, 17.42, 15.13, 15.11, 15.08, 15.00, 14.93.

[0533] 19F NMR (376 MHz, DMSO) 6 -107.31 - -112.03 (m, 4F), -130.95 - -132.95 (m, 2F). HR MS (ESI): m / z Calcd. for C33H30F6N202S4([M+H]+): 729.1173; Found: 729.1173.

[0534] Preparation of DEc (Supplementary Scheme 13)

[0535] 10

[0536]

[0537] Supplementary Scheme 13. Preparation of DEc. (Fig. 90)

[0538] A 2 mL quartz NMR tube (diameter 5 mm) charged with DEo (15.0 mg) and acetonitrile 15 (2.0 mL). The reaction mixture was irradiating UV (k = 302 nm, 2.8 mW cm2), for 1.5PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0539] h. After evaporation, residue was purified by silica gel column chromatography using a gradient of hexanes / ethyl acetate (0 to 14%) to afford DEc was obtained as a dark purple solid (9,2 mg, 61% yield).

[0540] 5 'HNMR (500 MHz, DMSO) 88.79 - 8.73 (m, 2H), 7.79 (dd, J= 8.7, 2.3 Hz, 1H), 7.58 (d, J= 2.1 Hz, 1H), 7.56 - 7.55 (m, 2H), 4.55 (qd, J= 7.4, 4.7 Hz, 1H), 3.66 (s, 3H), 3.64 (d, J = 1.1 Hz, 3H), 3.20 (hept, J = 6.7 Hz, 1H), 2.18 (s, 3H), 2.03 (d, J = 4.0 Hz, 3H), 1.45 (d, J= 7.3 Hz, 3H), 1.11 (dd, J= 11.6, 6.7 Hz, 6H).

[0541] 13C NMR (126 MHz, DMSO) 6195.72, 172.08, 159.05, 156.52, 150.69, 149.05, 147.10, 10 141.39, 140.63, 132.80, 127.09, 126.25, 125.38, 123.22, 122.02, 110.52, 72.54, 64.65, 52.99, 49.56, 49.50, 45.87, 38.59, 29.45, 22.30, 20.93, 17.48, 14.76, 14.63.

[0542] 19F NMR (376 MHz, DMSO) 6 -100.56 (d, J = 259.2 Hz, IF), -103.96 (d, J = 257.7 Hz, IF), -105.64 (d, J= 255.8 Hz, IF), -118.63 (d, J= 255.8 Hz, IF), -130.44 (d, J = 242.3 Hz, IF), -133.30 (d, J= 242.1 Hz, IF).

[0543] 15 HR MS (ESI): m / z Calcd. for C33H30F6N202S4([M+H]+): 729.1173; Found: 729.1173.

[0544] (iv) Synthesis of polymersPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0545] Preparation of poly(dodecyl acrylate) with BocDEo and BocDEc (Supplementary Scheme 14)

[0546]

[0547] 5

[0548] Supplementary Scheme 14. Preparation of poly(dodecyl acrylate) with (a) BocDEo and (b) BocDEc. Fig. 91

[0549] A stock solution was prepared by dissolving dodecyl acrylate (DDA, 0.65 mL, 2.4 mmol), AIBN (0.55 mg, 3.3 pmol), and toluene (0.54 mL). An aliquot (0.40 10 mL) of this stock solution was added to BocDEo or BocDEc (10.6 mg, 16 pmol), and the resulting mixtures were transferred to 2 mL amber glass ampoules equipped withPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0550] micro stir bars. The ampoules were degassed using three freeze-pump-thaw cycles and subsequently sealed under reduced pressure. Polymerization was conducted by heating and stirring the ampoules at 70 °C for 2 h, with a molar ratio of DDA: BocDE: AIBN = 50: 1: 0.07. The molar concentration of DDA in the reaction mixture was 5 2.0 M. Each polymer was purified by precipitation with methanol.

[0551] Supplementary Table 1. Molecular weights and monomer conversions of poly(dodecyl acrylate) prepared with BocDEo and BocDEc at 70 °C for 2 h.

[0552] Entry AdditivesaM

[0553]

[0554] SECx l05 bA / w / MnbConv. (%)c1 BocDEo 1.65 3.06 89 2 BocDEc 1.41 2.76 88 3 — 1.47 2.77 91 10

[0555] aAdditives were used from BocDEo (Supplementary Scheme 9) and BocDEc (Supplementary Scheme 10) as diarylethene backbone which does not have RAFT moiety.bNumber-average molecular weights and dispersities were determined by sizeexclusion chromatography using polystyrene standards.

[0556] 15cConversions were determined by1H NMR of a crude aliquot of the reaction mixture.

[0557] Preparation of polytmethyl acrylate) using DEo and DEc (Supplementary Scheme 15)PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0558] o MA, Al BN

[0559]

[0560] Supplementary Scheme 15. Preparation of poly(m ethyl acrylate) using (a) DEo and (b) DEc RAFT reagents. Fig. 92

[0561] 5 A stock solution was prepared by dissolving methyl acrylate (MA, 1.37 mL, 15.1 mmol), AIBN (1.24 mg, 7.6 pmol), and 2,2,2-trifluoroethanol (TFE, 2.41 mL). An aliquot (1.26 mL) of this stock solution was added to DEo or DEc (36.7 mg, 50 pmol) to mixture was prepared. Each resulting mixture was further divided into four portions (0.25 mL each) and transferred to four individual 2 mL amber glass ampoules equipped 10 with micro stir bar, yielding a total of eight ampoules. The ampoules were degassed using three freeze-pump-thaw cycles and subsequently sealed under reduced pressure. Polymerization was conducted by heating and stirring the ampoules at 70 °C with a molar ratio of MA: DE: AIBN = 100: 1: 0.05. The molar concentration of MA in the reaction mixture was 4.0 M.

[0562] 15PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0563] Supplementary Table 2. Molecular weights and monomer conversions data of poly(methyl acrylate) prepared using DEo and DEc at 70°C.

[0564] Entry Time (h) Mthx l03 aMSECx l03 bMv / MbConv. (%)

[0565]

[0566] cld1 3.3 12.6 1.78 30 2d2 6.3 12.1 1.83 65 3d3 8.0 12.3 1.90 85 4d4 8.4 12.2 1.92 89 5e1 3.2 6.4 1.73 29 6e2 4.9 7.9 1.63 48 7e3 6.3 9.2 1.55 65 8e4 7.7 10.1 1.51 81aA / nth= [MA] / [CTA] x conv.(MA) x A- / (MA) + A7(CTA).bNumber-average molecular 5 weights and dispersities were determined by size-exclusion chromatography using polystyrene standards.

[0567] cConversions were determined by1H NMR of a crude aliquot of the reaction mixture.dDEo was used as CTA.eDEc was used as CTA.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0568] Preparation of poly (vinyl acetate) using DEo and DEc (Supplementary Scheme 16)

[0569]

[0570] 5 Supplementary Scheme 16. Preparation of poly(vinyl acetate) using DEo and DEc. Fig. 93

[0571] A stock solution was prepared by dissolving vinyl acetate (VAc, 0.70 mL, 7.5 mmol), l,l'-Azobis(cyclohexane-l -carbonitrile) (V-40, 5.81 mg, 24 pmol), DEo (55.0 10 mg, 75 mol), and ethyl acetate (AcOEt, 0.60 mL). This stock solution was further divided into five portions (0.23 mL each) and transferred to five individual 2 mL amber glass ampoules equipped with micro stir bar, The ampoules were degassed using three freeze-pump-thaw cycles and subsequently sealed under reduced pressure. Polymerization was conducted by heating and stirring the ampoules at 75 °C with a 15 molar ratio of VAc: DEo: V-40 = 100: 1: 0.3. The molar concentration of VAc in the reaction mixture was 7.5 M.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0572] For comparison, polymerizations with DEc were also performed under otherwise identical conditions, except that the RAFT agent was replaced with DEc; two ampoules were prepared in this case.

[0573] 5 Supplementary Table 3. Molecular weights and monomer conversions of poly(vinyl acetate) prepared using DEo at 75°C.

[0574] Entry Time (h) Mthx l0

[0575]

[0576] 3 aMSECx l03 bMv / MbConv. (%)cld12 3.2 2.9 1.47 29 2d16 4.2 3.7 1.41 40 3d22 5.2 5.3 1.38 51 4d28 6.7 6.5 1.39 64 5d37 7.1 7.7 1.36 74 6d45 7.5 8.0 1.37 78 7e22 3.2 0.7 1.02 3 8e45 7.5 0.8 1.03 12

[0577] aMi111= [VAc] / [CTA] * conv.(VAc) x A / (VAc) + A / (CTA).bNumber-average 10 molecular weights and dispersities were determined by size-exclusion chromatography using polystyrene standards.

[0578] cConversions were determined by1H NMR of a crude aliquot of the reaction mixture.dDEo was used as CTA.eDEc was used as CTA.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0579] Preparation of poly(dodecyl acrylate) (DEcPDDA) using DEc (Supplementary Scheme 17) (Fig, 94)

[0580] DDA, Al BN Toluene, 70 □, 1 5 h DEc

[0581]

[0582] Supplementary Scheme 17. Preparation of poly(dodecyl acrylate) (DEcPDDA) using DEc.

[0583] A solution of dodecyl acrylate (DDA, 1.15 mL, 4.2 mmol), AIBN (2.41 mg, 15 pmol), DEc (152.9 mg, 0.21 mmol) and toluene (0.95 mL) prepared. The solution 10 was transferred to 5 mL amber glass ampoule equipped with a stir bars. The ampoule was degassed using three freeze-pump-thaw cycles and subsequently sealed under reduced pressure. Polymerization was conducted by heating and stirring the ampoule at 70 °C for 1.5 h, with a molar ratio of DDA: DEc: AIBN = 20: 1: 0.07. The molar concentration of DDA in the reaction mixture was 2.0 M. After 1.5 h. The mixture was 15 poured into cold methanol and separated oil was collected, washed with cold methanol and dried to afford controlled poly(dodecylacrylate) DEcPDDA as 749.1 mg of dark purple oil (76% conversion, Mn: 4,6 kPa, MvdMn: L43,),

[0584]

[0585] Complete photo-isomerization of DEcPDDA to poly(dodecyl acrylate) having DEo chain end (DEoPDDA) by Vis (1= 530 nm) irradiation (Supplementary Scheme 18)

[0586]

[0587] PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0588]

[0589] Supplementary Scheme 18. Preparation of poly(dodecyl acrylate) having DEo chain end (DEoPDDA) through photo isomerization. Fig. 95

[0590] 5 A 500 mL round bottom flask equipped with a stir bar charged with DEcPDDA

[0591] (Mn: 4.6 kDa, Đ / Mn: 1.43, 700 mg, 0.15 mmol) and hexanes (300 mL). The reaction mixture was stirred at room temperature with irradiating Vis (λ = 530 nm) for 2 h. As the irradiation time progressed, the color of the solution gradually changed from dark purple to colorless and transparent. After evaporation, DEoPDDA was obtained as a

[0592] 10 pale yellow oil. 700 mg (quant.).

[0593] Preparation of poly(vinyl acetate)-b-poly(dodecyl acrylate) (PDDA-b-PVAc) using DEoPDDA as a macro-CTA (Supplementary Scheme 19)

[0594]

[0595] Supplementary Scheme 19. Preparation of poly(vinyl acetate)-Z>-poly(dodecylPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0596] acrylate) (PDDA-b-PVAc) using DEoPDDA. Fig. 96

[0597] A solution of VAc (0.89 mL, 9.6 mmol), V-40 (10.1 mg, 41 μmol), DEoPDDA (632.0 mg, 0.137 mmol) and AcOEt (0.71 mL) was prepared. The solution was 5 transferred to 5 mL amber glass ampoule equipped with a stir bars. The ampoule was degassed using three freeze-pump-thaw cycles and subsequently sealed under reduced pressure. Polymerization was conducted by heating and stirring the ampoule at 75 °C for 23 h, with a molar ratio of VAc: DEoPDDA: V-40 = 70: 1: 0.3. The molar concentration of VAc in the reaction mixture was 6.0 M. After 23 h. The mixture was 10 poured into cold methanol precipitate was collected, washed with cold methanol and dried to afford controlled poly(vinyl acetate)-b-poly(dodecyl acrylate) (PDDA-b-PVAc) as a pale yellow solid (89% conversion, Mn: 12.6 kDa,

[0598]

[0599] : 1.30),

[0600] Chromatographic Fractionation of PDDA-b-PVAc

[0601] Automated flash chromatography was performed using a Biotage Selekt equipped with an external evaporative light scattering detector (ELSD). A commercial Biotage Sfar 50g silica column was used with a flow rate of 40 mL / min. Suitable gradients were determined through thin-layer chromatography experiments (Figure 80) and a linear gradient from 33% THF in toluene to 66% THF in toluene over 20 column 20 volumes (CV) was established. The column was equilibrated with two CV of the initial 33% THF in toluene eluent prior to loading the polymer. After equilibration, 825 mg of polymer was dissolved in 3.0 mL of the initial eluent, loaded directly onto the column,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0602] and subjected to the defined gradient. All chromatographic solvents were ACS grade or better and used without further purification. Elution was monitored through both the ELSD and the absorption at 300 nm from a photodiode array detector and the eluent was collected in 22 mL increments yielding 72 fractions. Fractions were dried using 5 a Genevac EZ-2 4.0 Series Centrifugal Evaporator followed by overnight in a 50°C vacuum oven. The mass recovery was taken to be the ratio between the collected and injected mass (Figure 81). Fractions were combined into 25 samples of approximately equal mass (>17.5 mg) and completely dried. Volume fractions were determined through1H NMR and overall molecular weights and dispersities were determined 10 through SEC (Supplementary Table 4).

[0603] Supplementary Table 4. Molecular characterization for the fractionated diblock copolymer library from the as-synthesized PDDA-b-PVAc.

[0604] Entry Fraction21Mass (mg)b / vcMnSECx 103 dĐ

[0605]

[0606] ndAs-Synthesized — 825 0.49 12.6 1.30

[0607] 501 2 34.7 0.14 11.2 1.32 502 3 70.5 0.21 9.8 1.43 503 4 37.0 0.27 9.2 1.48 504 5 29.1 0.30 9.7 1.43 505 6 22.2 0.33 10.0 1.39 506 7 17.7 0.37 10.2 1.34 507 8-9 29.4 0.41 10.7 1.29PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0608] 508 10-11 28.9 0.43 11.6 1.27 509 12-13 32.9 0.46 12.5 1.25 510 14 19.5 0.49 13.1 1.24 511 15 21.3 0.51 13.6 1.24 512 16 25.3 0.53 13.9 1.22 513 17 29.0 0.56 14.3 1.22 514 18 32.9 0.59 14.8 1.21 515 19 32.1 0.61 15.1 1.21 516 20 28.1 0.61 15.1 1.20 517 21 24.9 0.62 15.2 1.21 518 22 22.6 0.62 15.3 1.21 519 23 20.4 0.63 15.3 1.19 520 24 18.7 0.63 15.4 1.20 521 25-26 32.2 0.64 15.5 1.20 522 27-28 27.0 0.65 15.7 1.21 523 29-30 22.2 0.65 15.9 1.22 524 31-33 25.4 0.65 16.0 1.22 525 34-38 27.6 0.64 16.4 1.22

[0609] aFraction as referred to as the numbered test tube that was collected. Range of numbers indicates samples that were made from combined test tubes.bMass of the polymer sample were determined by weighing test tubes before and after fractionation.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0610] cVolume fractions were determined by H NMR and calculated using reference values of homopolymer densities ( ρv = 1.171, ρD = 0.942).dNumber-average molecular weights and dispersities were determined by size-exclusion chromatography using polystyrene standards.

[0611] 5

[0612] Estimation of Statistical Segment Lengths and Conformational Asymmetry, (ε = bV / bD)

[0613] To quantify the statistical segment lengths, b, of the constituent polymers, we turned to reference linear viscoelastic data. Approximations relied on the empirical 10 relationship between the molecular weight between entanglements, Me, density, p, and the packing length, p, which is established by Fetters et al.:3

[0614] Me = 361.9NAρp³ = 218ρp³

[0615] This is a temperature-independent relationship that has been established for various polymer classes, including polydienes, polyalkenes, poly(meth)acrylates, and others. The packing length is defined as the ratio of the occupied volume of a polymer chain (M / ρNA) to its mean end-to-end distance (⟨R²⟩₀) such that:

[0616] 20 =M=M°=

[0617]

[0618] P~ {R2)0pNAb2pNAb2

[0619] Here, the reference volume vo will be taken as a standard value, which isPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0620] selected to be 118 Å3in accordance with literature precedent.

[0621] To calculate the molecular weight between entanglements, we derive it from the plateau modulus (GN°) or plateau compliance (

[0622]

[0623] / °):

[0624] _ KpRT _ 1

[0625] Gn“ Me " 75

[0626] 5 where R, T, and K are the universal gas constant, temperature, and a constant that is either 0.8 or 1 depending on the model respectively. For internal consistency, we use K = 1. Molecular characteristics of PVAc and PDDA are summarized below in Supplementary Table 6. Using these values, we derive the conformational asymmetry for the system to be ε = bv / bD ~ 1.65.

[0627] 10

[0628] Supplementary Table 5. Molecular characterization of polymers from reference rheological data.

[0629] Entry ρ (g / cm3) G°N (kPa) T (°C) Me (kg / mol) b (Å)

[0630]

[0631] PVAc 1.171357435 8.4 6.1 PDDA 0.94217.2225 135 3.7

[0632] Small Angle X-ray Scattering.

[0633] Supplementary Table 6. Molecular and morphological characterization data for 15 the fractionated diblock copolymer library.

[0634] Entry / vaA / nSECx l03 bNcMorphology4TODT (°C)eAs-Synthesized 0.49 12.6 169 HEX — S01 0.14 11.2 162 BCC 50PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0635] 502 0.21 9.8 140 BCC 130 503 0.27 9.2 129 G 140 504 0.30 9.7 135 HEX 170 505 0.33 10.0 138 HEX 200 506 0.37 10.2 140 HEX 190 507 0.41 10.7 146 GYR 180 508 0.43 11.6 157 HEX / LAM 240 509 0.46 12.5 168 LAM

[0636] 510 0.49 13.1 175 LAM

[0637] 511 0.51 13.6 181 LAM

[0638] 512 0.53 13.9 184 LAM

[0639] 513 0.56 14.3 188 LAM

[0640] 514 0.59 14.8 194 LAM

[0641] 515 0.61 15.1 197 LAM

[0642] 516 0.61 15.1 197 LAM

[0643] 517 0.62 15.2 198 LAM

[0644] 518 0.62 15.3 199 LAM

[0645] 519 0.63 15.3 198 LAM

[0646] 520 0.63 15.4 200 LAM

[0647] 521 0.64 15.5 201 LAM

[0648] 522 0.65 15.7 203 LAM

[0649] 523 0.65 15.9 205 LAMPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0650] S24 0.65 16.0 207 LAM

[0651] S25 0.64 16.4 212 LAM —aVolume fractions were determined by 'H NMR and calculated using reference values of homopolymer densities (oρv = 1.171, ρD = 0.942).bNumber-average molecular weights and dispersities were determined by size-exclusion chromatography using polystyrene standards.cVolumetric degree of polymerizations were determined using 5 a reference volume of 118 Å3.dMorphology was determined through small-angle X- ray scattering. BCC, a, HEX, GYR, and LAM represent body-centered cubic spheres (Im3m), the c Frank-Kasper sphere phase (P42 / mnm), hexagonally-packed cylinders (p6mm), double-gyroid (Ia3d), and alternating lamellae respectively.eOrder-disorder transition temperature was determined through variable-temperature small-angle X-ray 10 scattering measurements in 10 °C increments and was taken as the last temperature an ordered morphology was observed. No order-disorder transition was observed for the as-synthesized material and S09-S25 due to thermal limitations.

[0652] Estimation of the PDDA-PVAc interaction parameter was done by collecting SAXS data on S01 (fv = 0.14) in the disordered state owing to its low TODT (50 °C). This is done to minimize effects of fluctuations that become stronger near the orderdisorder boundary. To account for changes in N due to thermal changes in the block densities, we use the following thermal dependencies of the densities of PDDA5and PVAc6where T is the temperature in °C:

[0653] 20 ρD = 0.95297 - 0.00063949TPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0654] 1

[0655] ρv = 0.82485 + 5.855 × 10-4T + 2.82 × 10-7T2

[0656] The SAXS scattering data was fitted to the random phase approximation structure factor previously derived for systems with asymmetric statistical segment 5 lengths using the following relationships:7

[0657] I

[0658] , raia22

[0659] ■ S(q) = CS(q)

[0660] S(q) = N[F(q) - 2χN]-1+ 2 / (1 - n / iup / ife) + (i - / )2gfo) / 2(1 - f)2[g{x1)g(x2) - h2{x1)h2(x2)] 2(% “I- 6~X— 1) 1 — 6~Xg(x) = - - -; / i(x) = -

[0661] x₁ = q²R²g,1, x₂ = q²R²g,2,1 1. D2, Nz2b2z1—~r

[0662]

[0663] Here, / (q) is the intensity as a function of q, which is related to the structure factor, S(q) through a scalar C that is a prefactor that covers the arbitrary intensity use, Rt is the radius of gyration of the zth block, and / is the volume fraction of block 1, 15 designated here to be the PVAc block. During the fit, we allow bD, f, and C to float while fixing all other parameters. We note that b of both blocks will vary withPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0664] temperature, but these effects are ignored here as its effects are expected to be minor. After extracting an estimate of x at various temperatures, we assume that χ takes the form A / T + B and linearly regress χ as a function of 1000 / T to capture its temperature dependencies to generate the phase diagram.

[0665] 5

[0666] Advantages and Improvements (citations refer to references for example 7), Block copolymers of acrylates and vinylesters are expected to exhibit useful functionality. Block copolymers are versatile building blocks for constructing ordered nanostructures owing to the spontaneous self-assembly into archetypal morphologies 10 with domain spacings of 10-100 nm--, thereby enabling applications in membranes-’-, photonics2, lithography- —, and drug delivery—’—.

[0667] However, there are only very limited methods for creating these block copolymers. Reliable access to the full phase diagram of diblock copolymers derived from acrylates (More activated monomers, MAMs) and vinyl esters (Less activated monomers, LAMs), which possess different reactivities have been hindered by synthetic constraints, side reactions, and the extremely narrow stability windows of certain morphologies.

[0668] One major obstacle is the block copolymerization of MAMs and LAMs. These monomers exhibit fundamentally different reactivities toward general

[0669] 20 controlled polymerization methods. Atom transfer radical polymerization (ATRP)— —, living anionic polymerization— —, and nitroxide mediated polymerization— — are well suited for the polymerization of more activated monomers (MAMs), in which thePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0670] active species are relatively stable. In contrast, the controlled polymerization of less activated monomers (LAMs), where the active species are less stable, can be achieved by living cationic polymerization—’—, iodine-transfer polymerization (ITP)— —, or cobalt-mediated radical polymerization (CMRP)— —. In other words, each

[0671] 5 polymerization method is optimized for the reactivity of the corresponding monomer.

[0672] In this context, reversible addition-fragmentation chain transfer (RAFT) polymerization— — is particularly unique in that, by selecting the appropriate substituents of the corresponding dithio compound, it can be applied to the controlled polymerization of both MAMs and LAMs. In RAFT polymerization, acrylates are 10 controlled by trithiocarbonates or dithiobenzoates— —, whereas vinyl esters require dithiocarbamates or xanthates with higher chain-transfer rates38. As a result, MAM- LAM block copolymerizations have typically suffered from homopolymer contamination and poor compositional control. Previous attempts to address this mismatch have included combining multiple controlled radical polymerizations through end-group transformation— —, employing acid-base responsive RAFT agents— —, or designing RAFT agents with intermediate reactivity toward both MAMs and LAMs—’—. Nevertheless, no approach has successfully switched the intrinsic reactivity of a RAFT agent without external additives.

[0673] In this study, we report a photo switchable RAFT agent that overcomes these 20 manufacturing barriers by enabling an innovative synthesis technique. Various examples presented herein demonstrate that photo switchable RAFT agents (e.g., incorporating a diarylethene) enables controlled radical polymerization of the blockPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0674] copolymerization of acrylates (MAMs) and vinyl acetate (LAMs). In one illustrative example, by reversibly switching the electronic state of the RAFT center under UV and visible light irradiation, direct synthesis of poly(dodecyl acrylate)-Z»-poly(vinyl acetate) was enabled without the need for changing RAFT agents or employing 5 complex multistep procedures. In combination with automated chromatographic fractionation, this approach yielded high-purity, narrowly dispersed libraries that systematically cover a wide range of block compositions. SAXS analysis across the library revealed a complete sequence of representative microphase morphologies — including the Frank-Kasper G phase — captured with high reproducibility, and, 10 critically, enabled the clear identification of phases with exceptionally narrow windows of stability.

[0675] Thus, the present disclosure demonstrates that integrating light-switchable RAFT agents with fractionation technology not only overcomes a long-standing synthetic barrier but also establishes a new framework for aligning experimental phase behavior with theoretical predictions. Furthermore, the approaches described herein can be extended to diverse MAM-LAM systems and other stimuli-responsive designs, accelerating the development of nanostructured materials for applications in membranes, photonics, lithography, and beyond.

[0676] 20 References for example 7

[0677] The following references are incorporated by reference herein.

[0678] 1. Leibler, L. Theory of microphase separation in block copolymers.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0679] Macromolecules 13, 1602-1617 (1980). https: / / doi. Org / 10.1021 / ma60078a047

[0680] 2. Matsen, M. W. & Bates, F. S. Unifying weak- and strong-segregation block copolymer theories. Macromolecules 29, 1091-1098 (1996).

[0681] http s: Z / d oi. org / 10, 1021 / a951138i

[0682] 5 3. Albert, J. N. L. & Epps, T. H. Self-assembly of block copolymer thin films.

[0683] Mater. Today 13, 24-33 (2010). h tips: / / doi. org / 10.1016 / S 1369-7021 ( 10)70106- 1

[0684] 4. Bates, F. S. & Fredrickson, G. H. Block copolymer thermodynamics: theory and experiment. Annu. Rev. Phys. Chem. 41, 525-557 (1990).

[0685] https: / / doi. org / 10.1146 / annurev.pc.41.100190.002521

[0686] 10 5. Abetz, V. Isoporous block copolymer membranes. Macromol. Rapid Commun. 36, 10-22 (2015). https: / / doi. org / 10.1002 / marc.201400556

[0687] 6. Moon, J. D., Freeman, B. D., Hawker, C. J. & Segalman, R. A. Can selfassembly address the permeability / selectivity trade-offs in polymer membranes? Macromolecules 53, 5649-5654 (2020).

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[0689] 7. Wang, Z., Chan, C. L. C., Zhao, T. H., Parker, R. M. & Vignolini, S. Recent advances in block copolymer self-assembly for the fabrication of photonic films and pigments. Adv. Optical Mater. 9, 2100519 (2021).

[0690] https: ZZdoi.org / 10.1002 / adom.20210Q519

[0691] 20 8. Kim, S. O., Solak, H. H., Stoykovich, M. P., Ferrier, N. J. & Nealey, P. F.

[0692] Epitaxial self-assembly of block copolymers on lithographically defined nanopatterned substrates.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0693] Nature 424, 411-414 (2003). h tips: / / doi. org / 10.1038 / n atureO 1775

[0694] 9. Bang, J., Jeong, U., Ryu, D. Y, Russell, T. P. & Hawker, C. J.

[0695] Block copolymer nanolithography: Translation of molecular level control to nanoscale patterns.

[0696] 5 Adv. Mater. 21, 4769-4792 (2009). https: / / doi.org / 10.1002 / adma.2008033Q2

[0697] 10. Jeong, S.-J., Kim, J. Y, Kim, B. H., Moon, H.-S. & Kim, S. O. Directed self-assembly of block copolymers for next generation nanolithography. Mater. Today 16, 468-476 (2013). htt s: / / doi. org / 10.1016 / j.matto:2013, 11.002

[0698] 11. Discher, B. M., Won, Y.-Y, Ege, D. S., Lee, J. C.-M. & Discher, D. E.

[0699] 10 Polymersomes: tough vesicles made from diblock copolymers. Science 284, 1143— 1146 (1999). https: / / doi.org / 10.1126 / science.284.5417, 1143

[0700] 12. Discher, D. E. & Eisenberg, A. Polymer vesicles. Science 297, 967-973 (2002). https: / / d0i.0rg / 10.1126 / science.1074972

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[0703] 14. Kato, M., Kamigaito, M., Sawamoto, M. & Higashimura, T. Polymerization of methyl methacrylate with the carbon tetrachloride / dichlorotris- 20 (triphenylphosphine)ruthenium(II) / methylaluminum bis(2,6-di-tert-butylphenoxide) initiating system: possibility of living radical polymerization. Macromolecules 28, 1721-1723 (1995). https: / / d0i.0rg / l 0.1021 / maOO 109a056PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0704] 15. Wang, J.-S. & Matyjaszewski, K. Controlled / "living" radical polymerization. Halogen atom transfer radical polymerization promoted by a Cu(I) / Cu(II) redox process. Macromolecules 28, 7901-7910 (1995).

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[0706] 5 16. Matyjaszewski, K., Jakubowski, W., Min, K., Tang, W. & Tsarevsky, N. V.

[0707] Diminishing catalyst concentration in atom transfer radical polymerization with reducing agents. Proc. Natl Acad. Sci. USA 103, 15309-15314 (2006).

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[0749] 39. Chiefari, J., Mayadunne, R. T. A., Moad, C. L., Moad, G. & Thang, S. H. Thiocarbonylthio compounds (SC(Z)S-R) in free-radical polymerization with reversible addition-fragmentation chain transfer (RAFT polymerization): effect of the activating group Z. Macromolecules 36, 2273-2283 (2003).

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[0751] 40. Mayadunne, R. T. A., Rizzardo, E., Chiefari, J., Chong, Y. K. & Thang, S. H. Living radical polymerization with reversible addition-fragmentation chain 20 transfer (RAFT polymerization) using dithiocarbamates as chain transfer agents.

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[0754] Hybridization of CMRP and ATRP: a direct living chain extension from poly(vinyl acetate) to poly(methyl methacrylate) and polystyrene. Macromolecules 48, 6832- 6838 (2015). htt s: / / doi. org / 10.1021 / ac s. m a crom ol.5 b 01101

[0755] 42. Nicolay, R., Kwak, Y. & Matyjaszewski, K. Synthesis of poly(vinyl 5 acetate) block copolymers by successive RAFT and ATRP with a bromoxanthate iniferter. Chem. Commun. 42, 5336-5338 (2008). https: / / doi org / 10.10 9 / B 810778 E 43. Debuigne, A., Wamant, J., Jerome, R., Voets, I., de Keizer, A., Cohen Stuart, M. A. & Detrembleur, C. Synthesis of novel well-defined poly(vinyl acetate)- Z»-poly(acrylonitrile) and derivatized water-soluble poly(vinyl alcohol)-Z»-poly(acrylic 10 acid) block copolymers by cobalt-mediated radical polymerization. Macromolecules 41, 2353-2360 (2008). https: / / doi.org / 10.1021 / ma702341v

[0756] 44. Altintas, O., Speros, J. C., Bates, F. S. & Hillmyer, M. A. Straightforward synthesis of model polystyrene-Z> / ocA poly(vinyl alcohol) diblock polymers. Polym. Chem. 9, 4243-4250 (2018). http: / 7doi. org / 10.1039 / C8P Y 00937F

[0757] 45. Benaglia, M., Chiefari, J., Chong, Y. K., Moad, G. & Thang, S. H.

[0758] Universal (switchable) RAFT agents. J. Am. Chem. Soc. 131, 6914-6915 (2009). h tips '. / / doi. or / 10 1021 / j a901955n

[0759] 46. Stace, S. J., Moad, G., Fellows, C. M. & Keddie, D. J. The effect of Z- group modification on the RAFT polymerization of A-vinyl pyrrolidone controlled by 20 “switchable” Y-pyridyl -functional dithiocarbamates. Polym. Chem. 6, 7119-7126 (2015). http s: / / doi. or / 10.1039 / C 5 P Y01021

[0760] 47. Keddie, D. J., Guerrero- Sanchez, C., Moad, G., Mulder, R. J. & Thang, S.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0761] H. Chain transfer kinetics of acid / base switchable A -aryl -A -pyridyl dithiocarbamate RAFT agents in methyl acrylate, / -vinylcarbazole and vinyl acetate polymerization. Macromolecules 45, 4205-4215 (2012). htt s: / / doi. org / 10.1021 / ma'300616g 48. Destarac, M., Charmot, D., Franck, X. & Zard, S. Z. Dithiocarbamates as 5 universal reversible addition-fragmentation chain transfer agents. Macromol. Rapid Commun. 21, 1035-1039 (2000). https: / / doi.org / ] 0.1002 / 1521 - 3927(20001001)21: 15<1035:: AID-MARC 1035>3,0. CO;2-5

[0762]

[0763] 49. Gardiner, J., Martinez-Botella, I., Tsanaktsidis, J. & Moad, G. Dithiocarbamate RAFT agents with broad applicability: the 3,5-dimethyl-lH- 10 pyrazole-1 -carbodithioates. Polym. Chem. 7, 481-492 (2016).

[0764] https: / / doi. org / 10.1039 / C 5PY01382H

[0765] 50. Irie, M., Fukaminato, T., Matsuda, K. & Kobatake, S. Photochromism of diarylethene molecules and crystals: memories, switches and actuators. Chem. Rev.

[0766] 114, 12174-12277 (2014). h ttps: / / doi.org / 10 1021 / cr500249p

[0767] 51. Irie, M. Diarylethene molecular photoswitches: concepts and functionalities (Wiley-VCH, 2021). ht.tps: / / doi.org / 10.1002 / 9783527822850

[0768] 52. Nagorny, S., Lederle, F, Udachin, V., Weingartz, T. & Schmidt, A.

[0769] Switchable mesomeric betaines derived from pyridinium-phenolates and bis(thienyl)ethane. Eur. J. Org. Chem. 2021, 3178-3189 (2021).

[0770] 20 https: / / doi. org / 10.1002 / ej oc.202100279

[0771] 53. Murphy, E. A., Chen, Y.-Q., Albanese, K., Blankenship, J. R. & Hawker, C. J. Efficient creation and morphological analysis of ABC triblock terpolymerPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0772] libraries. Macromolecules 55, 8875-8882 (2022).

[0773] h ttp s: / / doi. org / 10.1021 / acs. macromol.2c01480 <>

[0774] 54. Murphy, E. A., Skala, S. J., Kottage, D., Kohl, P. A. & Bates, C. M.

[0775] Accelerated discovery and mapping of block copolymer phase diagrams. Phys. Rev.

[0776] 5 Mater. 8, 015602 (2024). https: / / doi.org / 10.1103ZPhysRevMaterials.8.015602

[0777] 55. Murphy, E. A., Zhang, C., Bates, C. M. & Hawker, C. J. Chromatographic separation: a versatile strategy to prepare discrete and well-defined polymer libraries. Acc. Chem. Res. 57, 1202-1213 (2024). https: / / doi org / 10.1021 Zacs. accounts:4c00059

[0778] 56. Fang, X., Murphy, E. A., Kohl, P. A., Li, Y. & Gu, M. Universal phase 10 identification of block copolymers from physics-informed machine learning. J.

[0779] Polym. Sci. 63, 1433-1440 (2025). https: / / doi. org / 10.1002 / pol,2,0241063

[0780] 57. Murphy, E. A., Roth, K. G., Bates, M. W., Murphy, M. C. & Hawker, C. J. High-throughput generation of block copolymer libraries via click chemistry and automated chromatography. Macromolecules 58, 8369-8376 (2025).

[0781] https: / / doi.org / 10.1021 / acs.macromol.5c01024

[0782] 58. Princi, E., Vicini, S. & Pedemonte, E. Effect of ester group bulkiness of polyacrylates on miscibility with poly(vinyl acetate). Polym. Int. 58, 656-664 (2009).

[0783] 59. Schulze, M. W., Lewis, R. M., Lettow, J. H., Hickey, R. J. & Bates, F. S. Conformational asymmetry and quasicrystal approximants in linear diblock

[0784] 20 copolymers. Phys. Rev. Lett. 118, 207801 (2017)

[0785] https: / / doi. org / 10.1103 / PhysRevLett.118,207801

[0786] 60. Liberman, L., Coughlin, M. L., Weigand, S., Edmund, J. & Lodge, T. P.

[0787] IllPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0788] Impact of side-chain length on the self-assembly of hnear-bottl ebrush diblock copolymers. Macromolecules 55, 4947-4955 (2022).

[0789] / / doi. org / 10.1021 / ac s. macromol.2 cOO 758

[0790] 61. https: / / onlineHbrary.wiley.com / doi / pdf710. I002 / %28SICI%291Q99- 5 0488%2819970430%2935%3A6%3C945%3A%3AAID-POLB9%3E3.0. CO%3B2-G 62. https: / / doi o 10.1 OO2 / (S1CI)1099-0488(19990515)37: 10< I 023:: AID- POLB7>3.0. CO;2-T

[0791] 63. https: / / doi:org / 10,1021 / m a60042a037

[0792]

[0793] 64.' Universal (Switchable) RAFT Agents. Massimo Benaglia,f John Chiefari, 10 Yen K. Chong, Graeme Moad,* Ezio Rizzardo,* and San H. Than J. AM. CHEM.

[0794] SOC. 2009, 131, 6914-6915

[0795] Supplementary References for example 7 found in example 8

[0796] The following references are incorporated by reference herein.

[0797] 1. Sirianni, A. F., Tremblay, R. & Puddington, I. E. The molecular weight of polyvinyl acetate. Can. J. Chem. 36, 543-549 (1958).

[0798] https: / / doi.org / 10.1139 / v58-076

[0799] 2. Barbon, S. M., Song, J.-A., Chen, D., Zhang, C., Lequieu, J., Delaney, K. T., Anastasaki, A., Rolland, M., Fredrickson, G. H., Bates, M. W., 20 Hawker, C. J. & Bates, C. M. Architecture effects in complex spherical assemblies of (AB)n-type block copolymers. ACS Macro Lett. 9, 1745-1752 (2020).

[0800] https: / / doi.org / 10.1021 / acsmacrolett.0c00704PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0801] 3. Fetters, L. J., Lohse, D. J. & Graessley, W. W. Chain dimensions and entanglement spacings in dense macromolecular systems. J. Polym. Sci. B Polym. Phys. 37, 1023-1033 (1999). https: / / doi.org / 10.1002 / ( SICI) 1099- 0488(19990515)37:10<1023:: AID-POLB7>3.0. CQ:2-T

[0802] 5 4. Plazek, D. J. The temperature dependence of the viscoelastic behavior of poly(vinyl acetate). Polym. J. 12, 43-53 (1980).

[0803] https: / / doi.org / 10.1295 / polymj.12.43

[0804] 5. Pojman, J. A., Chekanov, Y., Wyatt, V., Bessonov, N. & Volpert, V. Numerical simulations of convection induced by Korteweg stresses in a miscible 10 polymer-monomer system: Effects of variable transport coefficients, polymerization rate and volume changes. Microgravity Sci. Technol. 21, 225-237 (2009).

[0805] https: / / doi.org / 10.1007 / s12217-008-9071-y

[0806]

[0807] 6. McKinney, J. E. & Simha, R. Configurational thermodynamic properties of polymer liquids and glasses. I. Poly(vinyl acetate). Macromolecules 7, 894-901 (1974). htt s: / / doi. org / 10.1021 Zm a60042a037

[0808] 7. Bates, F. S., Rosedale, J. H. & Fredrickson, G. H. Fluctuation effects in a symmetric diblock copolymer near the order-disorder transition. J. Chem. Phys.

[0809] 92, 6255-6270 (1990). https: / / doi.org / 10.1063 / 1.458350

[0810] 8. https: / / pubs.aip.org / aip / icp / article-abstract / 92 / 10 / 6255 / 784894 / Fluctuation- 20 effects-in-a-symmetriC"diblock?redirectedFrom=fulltext / PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0811] Composition of matter and method embodiments.

[0812] Embodiments of the present invention include, but are not limited to the following (referring to the Figures for example implementations).

[0813] 1. A composition of matter (e.g., RAFT agent) useful in a RAFT polymerization process, comprising:

[0814] a RAFT moiety (e.g., 102) coupled to an electron acceptor (e.g., 104) and a photo-switchable compound (e.g., 106).

[0815] 2. The composition of matter of clause 1, wherein the RAFT agent / moiety comprises a dithiocarbamate, a xanthate, or a thiuram disulfide.

[0816] 3. The composition of matter of clause 1 or 2, wherein the electron acceptor comprises a pyridine, pyridinium or its derivatives as following structural formula which R1, R2, and R3on the structural formula of the acceptor shown in Clause 3 are hydrogen, or alkyl, alkenyl, and aryl groups with 1 to 12 carbons.

[0817]

[0818] 4. The composition of matter of any of the clauses 1-3, wherein the photo-switchable compound comprises a diarylethene or a compound that reversibly switches a polymerization property of the RAFT agent in response to two different frequencies (e.g., visible and UV) of electromagnetic radiation.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0819] 5. The composition of matter of any of the clauses 1-4 comprising the

[0820]

[0821] 6. A polymer comprising a moiety of the composition of matter of any 5 of the clauses 1-5 or a structure formed from the RAFT agent during polymerization of a monomer mediated by the RAFT agent.

[0822] 7. The polymer of clause 6 comprising a polyvinylester or a polyacrylate, wherein the photo-switchable compound is reversibly photo-switchable between:

[0823] 10 a first state activating the RAFT agent to mediate the polymerization of a vinyl ester monomer (e.g., vinyl acetate) to form the polyvinylester;

[0824] a second state activating the RAFT agent to mediate the polymerization of an acrylate monomer (e.g., methyl acrylate) to form the polyacrylate; and

[0825] wherein control of a molecular weight of the polyacrylate during a RAFT 15 process using the RAFT agent activated by the photo-switchable compound in the second state is more accurate and predictable (e.g., experimental molecular weightPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0826] Mn better matches the predicted theoretical molecular weight) than when using the photo-switchable compound in the first state.

[0827] 8. A copolymer comprising a moiety of the composition of matter of any of the clauses 1-7 or clauses 18-22 or a structure derived from the composition of matter 5 of any of the clauses 1-7 or 18-22 during a polymerization reaction in a presence of a monomer and the composition of matter, or comprising the polymer of clause 6 or 7, the copolymer further comprising a MAM-LAM block copolymer, a polyacrylate and a polyvinylester, or an A-B block copolymer where A comprises a polyacrylate and B comprises a polyvinylester.

[0828] 10 9. The copolymer of clause 8, wherein the polyacrylate comprises polymethylacrylate and the polyvinylester comprises polyvinylacetate.

[0829] 10. The polymer or copolymer of any of the clauses 6-9 wherein the polymers have a poly dispersity (e.g., less than 1.5 or less than 1.3) and molecular weight in ranges (e.g., 1 kD to 50 kD or lOOkD) wherein the polacrylate and the 15 polyvinylester can be phase separated.

[0830] 11. A composition comprising the copolymer of clauses 8-10 wherein the polyacrylate and the polyvinylester are phase separated.

[0831] 12. A composition of matter of the structure:PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0832]

[0833] PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0834]

[0835] 13. Fig. 97 illustrates a method of polymerizing a monomer, comprising

[0836] obtaining (Block 1000) a compound comprising a RAFT moiety coupled to a 10 photoswitch (e.g., of any of the clauses 1-12 or synthesized according to the methodPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0837] of clause 27);

[0838] irradiating the photoswitch so as to switch the photoswitch into a first state (Block 1002) or a second state (Block 1004);

[0839] reacting the compound with a monomer so as to form a polymer, wherein the 5 photoswitch:

[0840] in the first state activates the RAFT agent to mediate polymerization of a first monomer to form a first polymer; and

[0841] in the second state activates the RAFT agent to mediate polymerization of a second monomer to form a second polymer

[0842] 10 so as to form a copolymer (Block 1006).

[0843] 14. The method of clause 14, further comprising:

[0844] irradiating the photoswitch in a composition comprising the first polymer (the macro-CTA) so as to switch the photoswitch into the second state;

[0845] reacting the composition comprising the photoswitch in the second state with the second monomer so as to form a copolymer comprising the first polymer and the second polymer.

[0846] 15. A polymer of any of the clauses 6-10 formed using the method clause 14.

[0847] 16. A copolymer of any of the clauses 6-10 formed using the method of 20 clause 14.

[0848] 17. The method or composition of any of the clauses, wherein the photoswitch is a photochrome or photo-isomerizable compound.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0849] 18. A composition of matter useful as a RAFT agent comprising the structure I or II:

[0850]

[0851] 5 or

[0852] wherein:

[0853] X is a sulfur atom or an oxygen atom,

[0854] Y is a substituted sulfur, nitrogen or an oxygen atom;

[0855] 10 R1is an aryl group, a fluoroalkyl group, or an alkyl group having from 1 to 12 carbon atoms,

[0856] R2is an alkyl group, a fluoroalkyl group, or an aryl group having from 1 to 12 carbon atoms,

[0857] R3and R4are each independently an alkyl group, an aryl group, a fluoroalkyl 15 group, or a fluoroaryl group having from 1 to 12 carbon atoms,

[0858] R5is an alkyl group having from 1 to 12 carbon atoms, andPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0859] R6is an organic group comprising carbon, hydrogen, optionally nitrogen and optionally oxygen.

[0860] 5

[0861] 19. The composition of matter of clause 18, wherein Y is the substituted nitrogen comprising an alkyl group having from 1 to 12 carbon atoms or an aryl group.

[0862] 20. The composition of matter of any of the clauses 18-19 wherein the 10 aryl groups include phenyl groups having from 0 to 5 substituents, pyridyl or quatemized pyridinium groups having from 0 to 4 substituents, pentafluorophenyl and perfluorotolyl groups and the substituents include at least one of an alkyl group having from 1 to 12 carbon atoms, a fluoro group, a cyano group, a trifluorom ethylPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0863] group, a nitro group, a pyridyl or N-methyl-2,6-dimethylpyndimum group or a fluoroalkyl group including perfluoroalkyl groups having from 1 to 12 carbon atoms.

[0864] 21. The composition of matter of any of the clauses 18-20 wherein: For the polymerization of methacrylate using the RAFT agent, R6is a 2- 5 cyanopropyl group, or

[0865] for the polymerization of acrylate, styrene, vinylester and vinylamide, R6is a 2-methoxycarbonylpropyl group, a 2 -methoxycarbonyl ethyl group, a 2-cyanoethyl group, or a cyanomethyl group.

[0866] 22. The composition of matter of any of the clauses 18-21 wherein 10 In Formula I, Ar is a monocyclic, bicyclic or large aromatic moiety, e.g., a phenylene group, or absent, or.

[0867] In general formula (II), Ar is a monocyclic, bicyclic or large aromatic moiety, e.g., a benzene ring.

[0868] 23. The composition of matter of any of the clauses 18 -22 wherein R6is a 2-cyanopropyl group, a, 2-cyanoethyl group, a cyanomethyl group or a 2- alkoxycarbonylpropyl group, or a 2-alkoxycarbonylethylgroup, or an alkoxycarbonylmethyl group each of which groups comprise from 1 to 12 carbon atoms on an alkyl group.

[0869] 24. The composition of matter of any of the clauses 18-22 wherein R6is 20 selected according to the reactivity of the monomer used in a polymerization of the monomer using the RAFT agent.

[0870] 25. A copolymer comprising or synthesized using the composition ofPCT / US25 / 58397 05 December 2025 (05.12.2025)

[0871] matter of any of the claims 18-24.

[0872] 26. The method of any of the claims 14-17 wherein the compound comprises the composition of matter of any of the clauses 18-22 or clauses 1-5 or clause 12.

[0873] 5 27. A method of making composition of matter useful as a RAFT agent, comprising:

[0874] coupling or combining an electron acceptor with a photo-switchable compound and a RAFT moiety or otherwise synthesizing the electron acceptor in combination with a phot-switchable compound and the RAFT moiety.

[0875] 10 28. The composition of matter of any of the claims 1-5, 12, or 18-24 manufactured or synthesized using the method of claim 27.

[0876] 29. A composition of matter, comprising:

[0877] a polymer composition comprising a plurality of diblock copolymer chains (e.g., 3702) each comprising a repeating unit comprising a MAM block (e.g. 3706) covalently bonded to a LAM block (e.g., 3708), wherein the MAM blocks and the LAM blocks are microphase separated so as to form a mixture of different microphases 3711 with different ordering.

[0878] 30. The composition of matter of clause 29, wherein the MAM block is 20 a polyacrylate and the LAM block is a polyvinylester.

[0879] 31. A composition of matter, comprising

[0880] 323PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0881] a polymer composition comprising a plurality of diblock copolymer chains (e.g., 3702) each comprising a repeating unit comprising a polyacrylate (having an alkyl sidechain having at least two or at least 4 carbon atoms) covalently bonded to a polyvinylester; and

[0882] 5 wherein the polyacrylate and the polyvinylester are microphase separated.

[0883] 32. The composition of matter of any of the clauses 29-31, wherein the ordered microphases are characterized by the presence of one or more diffraction peaks (e.g., 4000 in Fig. 40) in a diffraction measurement of the polymer composition.

[0884] 10

[0885] 33. The composition of clause 32, wherein the polymer composition comprises one or a mixture of two or more (or all of the) microphases comprising at least one of a BCC microphase 3710 (or a phase characterizable by the diffraction peaks associated with a BCC microphase), a hexagonal microphase 3712 (or a phase characterizable by the diffraction peaks associated with a hexagonal microphase), a sigma Frank-Kasper microphase (or a phase characterizable by the diffraction peaks associated with a sigma microphase), a gyroidal microphase 3717 (or a phase characterizable by the diffraction peaks associated with a gyroidal microphase), or a lamellar microphase 3716 (or a phase characterizable by the diffraction peaks

[0886] 20 associated with a lamellar microphase).

[0887] 34. The composition of matter of any of the clauses 29-33, wherein onePCT / US25 / 58397 05 December 2025 (05.12.2025)

[0888] or more of the microphases each comprise a minority phase 3718, comprising domains, in a majority phase 3720 comprising a matrix, and

[0889] the polyacrylate / MAM block is the minority phase and the polyvinylester / LAM block is the majority phase, or

[0890] 5 the polyacrylate / MAM block is the majority phase and the polyvinylester / LAM block is the minority phase.

[0891] 35. The composition of matter of any of the clauses 29-34, wherein adjacent ones of the domains or separated microphases have a center to center distance d in a range of 10 nanometers (nm)-100 nm.

[0892] 10 36. The composition of matter of any of the clauses 29-35, wherein the phases each have a volume fraction of at least 14%.

[0893] 37. The composition of matter of any of the clauses 29-36, wherein the microphases comprise at least one of:

[0894] a minority phase having a volume fraction in a range of 14%-26% and / or in a range so as to form the polymer composition having a BCC microphase structure, a minority phase having a volume fraction in a range of 27%-29% and / or in a range so as to form the polymer composition having a sigma microphase structure, a minority phase having a volume fraction in a range of 30%-40% and / or in a range so as to form the polymer composition having a hexagonal microphase

[0895] 20 structure,

[0896] a minority phase having a volume fraction in a range of 41%-43% and / or in a range so as to form the polymer composition having a gyroidal microphase structure,PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0897] or

[0898] one of the phases having a volume fraction in a range of 46%-65% and / or in a range so as to form the polymer composition having a lamellar microphase structure.

[0899] 5 38. The composition of matter of any of the clauses 30-37, wherein the polyvinylester is polyvinylacetate.

[0900] 39. The composition of matter of any of the clauses 30-48, wherein the polyacrylate comprises an alkyl side chain with more than one carbon atom.

[0901] 40. The composition of matter of any of the clauses 30-39, wherein the 10 polyacrylate is or comprises polyethylacrylate.

[0902] 41. The composition of matter of any of the clauses 29-40 wherein the diblock copolymer is of the structure:

[0903]

[0904] where n, m, k are integers and k=l or more than 1, more than 4, or k is 2-20 15 and b indicates that the polyacrylate and poly(vinyl ester) segments are connected as a block copolymer and the RAFT moiety with photoswitch can be present or removed by further process.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0905] In one or more embodiments, the RAFT moiety or chain end in the polymers and copolymers can be removed by reduction or substitution reactions.

[0906] 42. The method of any of the clauses 14-17 or 26-27 further comprising reacting the first monomer at a first temperature and for a first reaction time 5 that is calibrated to obtain a length of the first polymer (the macro-CTA) having a first desired molecular weight;

[0907] reacting the second monomer at a second temperature and for a second reaction time that is calibrated to obtain a length of the second polymer having a second desired molecular weight, and

[0908] 10 switching the photoswitch or photoswitchable compound after time intervals that determined or control the reaction times.

[0909] 43. The composition of matter of any of the clauses 29-42 fabricated using the RAFT agent of any of the clausesl-13, 18-25, and / or the method of any of the clauses 14-17.

[0910] 44. The composition of matter or method of any of the clauses 1-44, wherein the first polymer and / or second polymer are combined to form the copolymer without further purification.

[0911] 45. The composition of matter or method of any of the clauses 1-44, wherein the intrinsic reactivity of the RAFT agent is switched toward the controlled

[0912] 20 polymerization of MAMs and L Ms without using any external chemicals or additives, see for example first paragraph on page 91.PCT / US25 / 58397 05 December 2025 (05.12.2025)

[0913] References

[0914] The following references are incorporated by reference herein.

[0915] 1Benaglia, M., Chiefari, J., Chong, Y. K., Moad, G., Rizzardo, E., Thang, S. H. J. Am. Chem. Soc., 2009, 131, 6914-6915.

[0916] 52Keddie, D. J., Sanchez, C. G., Moad, G., Mulder, R. J., Rizzardo, E., Thang, S. H. Macromolecules 2012, 45, (10), 4205-4215.

[0917] Conclusion

[0918] 10 This concludes the description of the preferred embodiment of the present invention. The foregoing description of one or more embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended 15 that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.

Claims

WHAT IS CLAIMED IS:

1. A composition of matter useful in a RAFT polymerization process, comprising:a Reversible addition - fragmentation chain transfer (RAFT) moiety coupled to an electron acceptor and a photo-switchable compound.

2. The composition of matter of claim 1, wherein the RAFT moiety comprises a dithiocarbamate, a xanthate, or a thiuram disulfide.

3. The composition of matter of claim 1, wherein the electron acceptor comprises a pyridine, pyridinium or its derivatives as shown in the following structural formula:wherein R1, R2, and R3are hydrogen, or alkyl, alkenyl, and aryl groups with 1 to 12 carbons.

4. The composition of matter of claim 1, wherein the photo-switchable compound comprises a diarylethene or a compound that reversibly switches a polymerization property of the composition of matter as a RAFT agent in response to two different frequencies of electromagnetic radiation.

5. The composition of matter of claim 1 comprising the structure:

6. A polymer comprising a moiety of the composition of matter of claim 1 or a structure formed from the composition of matter comprising a RAFT agent during polymerization of a monomer mediated by the RAFT agent.

7. The polymer of claim 6 comprising a polyvinylester or a polyacrylate, wherein the photo-switchable compound is reversibly photo-switchable between:a first state activating the RAFT agent to mediate the polymerization of a vinyl ester monomer to form a polyvinylester;a second state activating the RAFT agent to mediate the polymerization of an acrylate monomer to form a polyacrylate; andwherein control of a molecular weight of the polyacrylate during a RAFT process using the RAFT agent activated by the photo-switchable compound in the second state is more accurate and predictable than when using the photo-switchable compound in the first state.

8. A copolymer comprising a moiety of the composition of matter ofclaim 1 or a structure derived from the composition of matter of claim 1 during a polymerization reaction in a presence of a monomer and the composition of matter, or comprising the polymer of claim 6 or 7, the copolymer further comprising a MAM-LAM block copolymer, a polyacrylate and a polyvinylester, or an A-B block copolymer where A comprises a polyacrylate and B comprises a polyvinylester.

9. The copolymer of claim 8, wherein the polyacrylate comprises polymethylacrylate and the polyvinylester comprises polyvinylacetate.

10. The polymer or copolymer of claim 6 wherein the polymers have a poly dispersity and molecular weight in ranges wherein the polacrylate and the polyvinylester can be phase separated.

11. A composition comprising the copolymer of claim 8 wherein the polyacrylate and the polyvinylester are phase separated.

12. A composition of matter of the structure:or§orwherein n and k can be any integer.

13. A method of polymerizing a monomer, comprisingobtaining a compound comprising a RAFT agent comprising a RAFT moiety coupled to a photoswitch;irradiating the photoswitch so as to switch the photoswitch into a first state or a second state;reacting the compound with a monomer so as to form a polymer, wherein the photoswitch:in the first state activates the RAFT agent to mediate polymerization of a first monomer to form a first polymer; andin the second state activates the RAFT agent to mediate polymerization of a second monomer to form a second polymer.

14. The method of claim 13, further comprising:irradiating the photoswitch in a composition comprising the first polymer so as to switch the photoswitch into the second state;reacting the composition comprising the photoswitch in the second state with the second monomer so as to form a copolymer comprising the first polymer and the second polymer.

15. A polymer or copolymer of claim 6 formed using the method of claim 14.

16. A polymer or copolymer of claim 8 formed using the method of claim 14.

17. The composition of matter of claim 1, wherein the photoswitch is a photochrome or photo-isomerizable compound.

18. A composition of matter useful as a Reversible addition - fragmentation chain transfer (RAFT) agent comprising the structure I or II:( I )orwherein:X is a sulfur atom or an oxygen atom,Y is a substituted sulfur, nitrogen or an oxygen atom;R1is an aryl group, a fluoroalkyl group, or an alkyl group having from 1 to 12carbon atoms,R2is an alkyl group, a fluoroalkyl group, or an aryl group having from 1 to 12carbon atoms,R3and R4are each independently an alkyl group, an aryl group, a fluoroalkylgroup, or a fluoroaryl group having from 1 to 12 carbon atoms,R5is an alkyl group having from 1 to 12 carbon atoms, andR6is an organic group comprising carbon, hydrogen, nitrogen and oxygen.

19. The composition of matter of claim 18, wherein Y is the substituted nitrogen comprising an alkyl group having from 1 to 12 carbon atoms or an arylgroup.

20. The composition of matter of claim 18 wherein the aryl groups include at least one of a phenyl group having from 0 to 5 substituents, a pyridyl orquatemized pyridinium group having from 0 to 4 substituents, or a pentafluorophenyl and perfluorotolyl group and the substituents include at least one of an alkyl group having from 1 to 12 carbon atoms, a fluoro group, a cyano group, a trifluoromethyl group, a nitro group, a pyridyl or N-methyl-2,6-dimethylpyridinium group or a fluoroalkyl group including a perfluoroalkyl group having from 1 to 12 carbon atoms.

21. The composition of matter of claims 18 wherein:for the polymerization of methacrylate using the RAFT agent, R6is a 2-cyanopropyl group, orfor the polymerization of acrylate, styrene, vinylester or vinylamide, R6is a 2-methoxycarbonylpropyl group, a 2 -methoxycarbonyl ethyl group, a 2-cyanoethyl group, or a cyanomethyl group.

22. The composition of matter of claim 18 whereinIn Formula I, Ar is a monocyclic, bicyclic or large aromatic moiety such as, a phenylene group, or absent, or,In general formula (II), Ar is a monocyclic, bicyclic or large aromatic moiety, such as a benzene ring.

23. The composition of matter of claim 18 wherein R6is a 2-cyanopropyl group, a 2-cyanoethyl group, a cyanomethyl group or a 2-alkoxycarbonylpropyl group, or a 2-alkoxycarbonylethylgroup, or an alkoxycarbonylmethyl group each of which groups comprise from 1 to 12 carbon atoms on an alkyl group.

24. The composition of matter of claim 18 wherein R6is selected according to the reactivity of the monomer used in a polymerization of the monomer using the RAFT agent.

25. A copolymer comprising or synthesized using the composition of matter of claim 18.

26. The method of claim 14 wherein the compound comprises the composition of matter of claim 18.

27. A method of making composition of matter useful as a RAFT agent, comprising:coupling or combining an electron acceptor with a photo-switchable compound and a RAFT moiety or otherwise synthesizing the electron acceptor in combination with a photo-switchable compound and the RAFT agent.

28. The composition of matter of claim 1 manufactured or synthesized using the method of claim 27.

29. A composition of matter, comprising:a polymer composition comprising a plurality of diblock copolymer chains each comprising a repeating unit comprising a MAM block covalently bonded to a LAM block, wherein the MAM blocks and the LAM blocks are microphase separated so as to form a mixture of different microphases with different ordering.

30. The composition of matter of claim 29, wherein the MAM block is a polyacrylate and the LAM block is a polyvinylester.

31. A composition of matter, comprisinga polymer composition comprising a plurality of diblock copolymer chains each comprising a repeating unit comprising a polyacrylate (having an alkyl sidechain having at least two or at least 4 carbon atoms) covalently bonded to a polyvinylester; andwherein the polyacrylate and the polyvinylester are microphase separated.

32. The composition of matter of claim 29, wherein the ordered microphases are characterized by the presence of one or more diffraction peaks in a diffraction measurement of the polymer composition.

33. The composition of claim 32, wherein the polymer composition comprises one or a mixture of two or more microphases comprising at least one of a BCC microphase (or a phase characterizable by the diffraction peaks associated with a BCC microphase), a hexagonal microphase (or a phase characterizable by the diffraction peaks associated with a hexagonal microphase), a sigma Frank-Kasper microphase (or a phase characterizable by the diffraction peaks associated with a sigma microphase), a gyroidal microphase (or a phase characterizable by the diffraction peaks associated with a gyroidal microphase), or a lamellar microphase (or a phase characterizable by the diffraction peaks associated with a lamellar microphase).

34. The composition of matter of claim 29, wherein one or more of the microphases each comprise a minority phase, comprising domains, in a majority phase comprising a matrix, andthe polyacrylate / MAM block is the minority phase and the polyvinylester / LAM block is the majority phase, orthe polyacrylate / MAM block is the majority phase and the polyvinylester / LAM block is the minority phase.

35. The composition of matter of claim 29, wherein adjacent ones of the domains or separated microphases have a center to center distance in a range of 10 nanometers (nm)-100 nm.

36. The composition of matter of claim 29, wherein the phases each have a volume fraction of at least 14%.

37. The composition of matter of claim 29, wherein the microphases comprise at least one of:a minority phase having a volume fraction in a range of 14%-26% and / or in a range so as to form the polymer composition having a BCC microphase structure, a minority phase having a volume fraction in a range of 27%-29% and / or in a range so as to form the polymer composition having a sigma microphase structure, a minority phase having a volume fraction in a range of 30%-40% and / or in arange so as to form the polymer composition having a hexagonal microphase structure,a minority phase having a volume fraction in a range of 41%-43% and / or in a range so as to form the polymer composition having a gyroidal microphase structure, orone of the phases having a volume fraction in a range of 46%-65% and / or in a range so as to form the polymer composition having a lamellar microphase structure.

38. The composition of matter of claim 30, wherein the polyvinylester is polyvinylacetate.

39. The composition of matter of claim 30, wherein the polyacrylate comprises an alkyl side chain with more than one carbon atom.

40. The composition of matter of claim 30, wherein the polyacrylate is or comprises polyethylacrylate.

41. The composition of matter of any of claim 29 wherein the diblock copolymer is of the structure:where n, m, k are integers and k is 4 or more and b indicates that the polyacrylate and poly(vinyl ester) segments are connected as a block copolymer and the RAFT moiety with photoswitch can be present or removed.

42. The method of claim 14 further comprisingreacting the first monomer at a first temperature and for a first reaction time that is calibrated to obtain a length of the first polymer having a first desired molecular weight;reacting the second monomer at a second temperature and for a second reaction time that is calibrated to obtain a length of the second polymer having a second desired molecular weight, andswitching the photoswitch or photoswitchable compound after time intervals that determine or control the reaction times.

43. The composition of claim 29 fabricated using the RAFT agent of claim 1, and / or the method of claim 14.

44. The method of claim 14, wherein the first polymer is not purified prior to using the RAFT agent for forming the copolymer (the copolymerization is applied to the unpurified first polymer or MACRO-CTA).

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