Poly(arylene ether ether nitrile)s containing flexible alkylsulfonated side chains for polymer electrolyte membranes

A series of poly(arylene ether ether nitrile)s with different chain lengths of the alkylsulfonates (SPAEEN‐x: x refers number of the methylene units) are successfully synthesized for fuel cell applications. The polymers produced flexible and transparent membranes by solvent casting. The resulting membranes display a high thermal stability, oxidative stability, and higher proton conductivity than that of Nafion 117 at 80 °C and 95% relative humidity (RH). Furthermore, the SPAEEN‐12 with the longest alkylsulfonated side chain exhibits a higher proton conductivity at 30% RH than that of SPAEEN‐6 despite the lower IEC value, which indicates that the introduction of longer alkylsufonated side chains to the polymer main chain induces an efficient proton conduction by the formation of a well‐developed phase‐separated morphology. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 21–29     

New hybrid membranes based on phosphonic acid functionalized silica particles for PEMFC

This work concerns the development of hybrid organic/inorganic membranes from styrenic phosphonic polymers. The phosphonic charge, composed phosphonic polymers grafted onto silica nanoparticles, was obtained by “grafting onto” method. It consists of synthesizing first the polymer, and then the terminal functions of the latter react with silanol groups of silica. The phosphonated polymer was isolated in two steps, that is, an ATRP polymerization of 4‐chloromethylstyrene followed by Mickaelïs‐Arbusov reaction. After the grafting onto silica, membranes are prepared through formulation containing the charge and the polymer matrix PVDF‐HFP, which are dispersed in DMF. The acid form is obtained by hydrolysis in chlorydric acid. The membrane possessing a 40 wt % charge ratio (IEC = 1.08 meq g^?1) was selected as reference. A proton conductivity of 65 mS cm^?1 at 80 °C was measured in immersed conditions. When the membrane is no more immersed, the value decreases drastically (0.21 mS cm^?1 at 120 °C and 25% RH). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Highly phosphonated poly(N‐phenylacrylamide) for proton exchange membranes

A novel highly phosphonated poly(N‐phenylacrylamide) ( PDPAA ) with an ion‐exchange capacity (IEC) of 6.72 mequiv/g was synthesized by the radical polymerization of N‐[2,4‐bis(diethoxyphosphinoyl)phenyl]acrylamide ( DEPAA ), followed by the hydrolysis with trimethylsilyl bromide. Then, the crosslinked PDPAA membrane was successfully prepared by the electrophilic substitution reaction between the aromatic rings of PDPAA and the carbocation formed from hexamethoxymethylmelamine (CYMEL) as a crosslinker in the presence of methanesulfonic acid. The crosslinked PDPAA membrane had high oxidative stability against Fenton's reagent at room temperature. The proton conductivity of the crosslinked PDPAA membrane was 8.8 × 10^?2 S/cm at 95% relative humidity (RH) and 80 °C, which was comparable to Nafion 112. Under low RH, the crosslinked PDPAA membrane showed the proton conductivity of 1.9 × 10^?3 and 4.7 × 10^?5 S/cm at 50 and 30% RH, respectively. The proton conductivity of the crosslinked PDPAA membrane lied in the highest class among the reported phosphonated polymers, and, consequently, the very high local concentration of the acids of PDPAA (IEC = 6.72 mequiv/g) achieved high and effective proton conduction under high RH. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Proton conducting membranes based on poly(vinyl chloride) graft copolymer electrolytes

The direct preparation of proton conducting poly(vinyl chloride) (PVC) graft copolymer electrolyte membranes using atom transfer radical polymerization (ATRP) is demonstrated. Here, direct initiation of the secondary chlorines of PVC facilitates grafting of a sulfonated monomer. A series of proton conducting graft copolymer electrolyte membranes, i.e. poly(vinyl chloride)‐g‐poly(styrene sulfonic acid) (PVC‐g‐PSSA) were prepared by ATRP using direct initiation of the secondary chlorines of PVC. The successful syntheses of graft copolymers were confirmed by ¹H‐NMR and FT‐IR spectroscopy. The images of transmission electron microscopy (TEM) presented the well‐defined microphase‐separated structure of the graft copolymer electrolyte membranes. All the properties of ion exchange capacity (IEC), water uptake, and proton conductivity for the membranes continuously increased with increasing PSSA contents. The characterization of the membranes by thermal gravimetric analysis (TGA) also demonstrated their high thermal stability up to 200°C. The membranes were further crosslinked using UV irradiation after converting chlorine atoms to azide groups, as revealed by FT‐IR spectroscopy. After crosslinking, water uptake significantly decreased from 207% to 84% and the tensile strength increased from 45.2 to 71.5 MPa with a marginal change of proton conductivity from 0.093 to 0.083 S cm^?1, which indicates that the crosslinked PVC‐g‐PSSA membranes are promising candidates for proton conducting materials for fuel cell applications. Copyright © 2008 John Wiley & Sons, Ltd.     

The impact of alkyl tri‐methyl ammonium side chains on perfluorinated ionic membranes for electrochemical applications

Three different perfluorinated type polymers as anion exchange membranes for electrochemical applications were studied. They have a sulfonamide linkage to a spacer methylene chain attached to a tri‐methyl ammonium cation, specifically using a three carbon spacer chain (PFAEM_H_C3), and methylated imide polymers with three (PFAEM_CH3_C3) and six carbon spacer chain (PFAEM_CH3_C6). There are significant number of zwitterionic side chains in the PFAEM_H_C3 polymer and very few in the PFAEM_CH3_C3 or the PFAEM_CH3_C6 polymer. They have similar halide conductivity, but the PFAEM_CH3_C6 showed highest OH^? conductivity, 122 mS cm^?1 at 80 °C and 95% RH. The larger spacer chain polymer, PFAEM_CH3_C6 has a higher water uptake value (λ = 9) compared to PFAEM_CH3_C3(λ = 7) at 60 °C and 95% RH in the Cl^? form. Therefore, it has a larger domain spacing of 4.9 nm versus 4.1 nm from small angle X‐ray scattering data. The polymer was characterized by FTIR and DFT was used to fully assign the spectra. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 700–712     

Chitosan‐based composite membranes containing chitosan‐coated carbon nanotubes for polymer electrolyte membranes

Considering the poor dispersion and inert ionic conduction ability of carbon nanotubes (CNTs), functionalization of CNTs is a critical issue for their application in polymer electrolyte membranes. Herein, CNTs were functionalized by the polyelectrolyte, chitosan (CS), via a facile noncovalent surface‐deposition method. The obtained CS‐coated CNTs (CS@CNTs) were then incorporated into the CS matrix and fabricated composite membranes. The CS coating can enhance the compatibility between CNTs and the matrix, thus ensuring the homogenous dispersion of CS@CNTs and effectively improved the mechanical properties of the composites. Moreover, the CS coating can make CS@CNTs act as an additional proton‐conducting pathway through the membranes. The CS/CS@CNTs‐1 composite shows the highest proton conductivity of 3.46 × 10⁻² S cm⁻¹ at 80°C, which is about 1.5‐fold of the conductivity of pure CS membrane. Consequently, the single cell equipped with CS/CS@CNTs‐1 membrane exhibits a peak power density of 47.5 mW cm⁻², which is higher than that of pure CS (36.1 mW cm⁻²).     

Poly(tetrafluorostyrenephosphonic acid)–polysulfone block copolymers and membranes

A series of ionic ABA triblock copolymers having a central polysulfone (PSU) block and poly(2,3,5,6,‐tetrafluorostyrene‐4‐phosphonic acid) (PTFSPA) outer blocks with different lengths were prepared and studied as electrolyte membranes. PSU with terminal benzyl bromide was used as a bifunctional macroinitiator for the formation of poly(2,3,4,5,6‐pentafluorostyrene) (PPFS) blocks by atom transfer radical polymerization. Selective and complete phosphonation of the PPFS blocks was achieved via a Michaelis?Arbuzov reaction using tris(trimethylsilyl)phosphite at 170 °C. Copolymer films were cast from solution and subsequently fully hydrolyzed to produce transparent flexible proton conducting PTFSPA‐b‐PSU‐b‐PTFSPA membranes with a thermal stability reaching above 270 °C under air, and increasing with the PTFSPA content. Studies of thin copolymer electrolyte membranes by tapping mode atomic force microscopy showed phase separated morphologies with continuous proton conducting PTFSPA nano scale domains. Block copolymer membranes reached a proton conductivity of 0.08 S cm^?1 at 120 °C under fully hydrated conditions, and 0.8 mS cm^?1 under 50% relative humidity at 80 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4657–4666     

Polymer electrolyte membranes based on p‐toluenesulfonic acid doped poly(1‐vinyl‐1,2,4‐triazole): Synthesis,thermal and proton conductivity properties

Throughout this work, the synthesis, thermal as well as proton conducting properties of acid doped heterocyclic polymer were studied under anhydrous conditions. In this context, poly(1‐vinyl‐1,2,4‐triazole), PVTri was produced by free radical polymerization of 1‐vinyl‐1,2,4‐triazole with a high yield. The structure of the homopolymer was proved by FTIR and solid state ¹³C CP‐MAS NMR spectroscopy. The polymer was doped with p‐toluenesulfonic acid at various molar ratios, x = 0.5, 1, 1.5, 2, with respect to polymer repeating unit. The proton transfer from p‐toluenesulfonic acid to the triazole rings was proved with FTIR spectroscopy. Thermogravimetry analysis showed that the samples are thermally stable up to ～250 °C. Differential scanning calorimetry results illustrated that the materials are homogeneous and the dopant strongly affects the glass transition temperature of the host polymer. Cyclic voltammetry results showed that the electrochemical stability domain extends over 3 V. The proton conductivity of these materials increased with dopant concentration and the temperature. Charge transport relaxation times were derived via complex electrical modulus formalism (M*). The temperature dependence of conductivity relaxation times showed that the proton conductivity occurs via structure diffusion. In the anhydrous state, the proton conductivity of PVTri1PTSA and PVTri2PTSA was measured as 8 × 10^?4 S/cm at 150 °C and 0.012 S/cm at 110 °C, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1016–1021, 2010     

Polymer electrolyte membrane based on poly(ether sulfone) containing binaphthyl units with pendant perfluoroalkyl sulfonic acids

A novel poly(ether sulfone) containing binaphthyl units with pendant perfluoroalkyl sulfonic acids ( BNSH‐PSA ) was developed for a polymer electrolyte membrane (PEM). The BNSH‐PSA was prepared by the aromatic nucleophilic substitution reaction of 1,1′‐binaphthyl‐4,4′‐diol and 4,4′‐dichlorodiphenylsulfone, followed by the bromination with bromine, and then the Ullman coupling reaction with potassium 1,1,2,2,‐tetrafluoro‐2‐(1,1,2,2‐tetrafluoro‐2‐iodoethoxy) ethanesulfonate ( PSA‐K ). The ion exchange capacity (IEC) of BNSH‐PSA was estimated to be 1.91 mequiv/g, which corresponded to full conversion to the perfluroalkyl sulfonic acids. The BNSH‐PSA membrane prepared by solution casting showed high oxidative and dimensional stability. High proton conductivity comparable to the Nafion 117 membrane was accomplished in the range of 30–95% relative humidity (RH) due to the high acidity of the perfluoroalkyl sulfonic acids. Furthermore, atomic force microscopic observation supported the formation of the phase‐separated structure that the hydrophilic domains were well dispersed and connected to each other. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Synthesis of sulfonated poly(imidoaryl ether sulfone) membranes for polymer electrolyte membrane fuel cells

New sulfonated poly(imidoaryl ether sulfone) copolymers derived from sulfonated 4,4′‐dichlorodiphenyl sulfone, 4,4′‐dichlorodiphenyl sulfone, and imidoaryl biphenol were evaluated as polymer electrolyte membranes for direct methanol fuel cells. The sulfonated membranes were characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis, and proton nuclear magnetic resonance spectra. The state of water in the membranes was measured with differential scanning calorimetry, and the existence of free water and bound water was discussed in terms of the sulfonation level. The 10 wt % weight loss temperatures of these copolymers were above 470 °C, indicating excellent thermooxidative stability to meet the severe criteria of harsh fuel‐cell conditions. The proton conductivities of the membranes ranged from 3.8 × 10^?2 to 5 × 10^?2 S/cm at 90 °C, depending on the degree of sulfonation. The sulfonated membranes maintained the original proton conductivity even after a boiling water test, and this indicated the excellent hydrolytic stability of the membranes. The methanol permeabilities ranged from 1.65 × 10^?8 to 5.14 × 10^?8 cm²/s and were lower than those of other conventional sulfonated ionomer membranes, particularly commercial perfluorinated sulfonated ionomer (Nafion). The properties of proton and methanol transport were discussed with respect to the state of water in the membranes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5620–5631, 2005     

Preparation of polymer electrolyte membranes based on poly(phenylene oxide) with different side chain lengths of phosphonic acid

A series of poly(phenylene oxide) (PPO) polymers bearing phosphonic acid groups on the methyl group and on the phenyl ring are synthesized as membrane materials for fuel cell applications. These phosphonic acid‐based PPO membranes exhibited high chemical resistance, dimensional stability, and good proton conductivity even under low humidity condition. Among the membranes, the one in which the phosphonic acid moiety is attached to the polymer main chain with ? CO(CH₂)₅? shows highest proton conductivity under overall conditions even though it has the lowest water uptake and IEC value. A well‐defined separation of the hydrophilic and hydrophobic phases suggests the phosphonic acid groups to form proton conduction channels via interchain hydrogen bonding. A high storage modulus of the membranes in various temperature ranges indicates that the membranes are suitable for use under a high temperature and low humidity conditions. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019     

Anhydrous proton conducting membranes based on crosslinked graft copolymer electrolytes

A comb-like copolymer consisting of a poly(vinylidene fluoride-co-chlorotrifluoroethylene) backbone and poly(hydroxy ethyl acrylate) side chains, i.e. P(VDF-co-CTFE)-g-PHEA, was synthesized through atom transfer radical polymerization (ATRP) using CTFE units as a macroinitiator. Successful synthesis and a microphase-separated structure of the copolymer were confirmed by proton nuclear magnetic resonance (¹H NMR), FT-IR spectroscopy, and transmission electron microscopy (TEM). This comb-like polymer was crosslinked with 4,5-imidazole dicarboxylic acid (IDA) via the esterification of the –OH groups of PHEA and the –COOH groups of IDA. Upon doping with phosphoric acid (H₃PO₄) to form imidazole–H₃PO₄ complexes, the proton conductivity of the membranes continuously increased with increasing H₃PO₄ content. A maximum proton conductivity of 0.015 S/cm was achieved at 120 °C under anhydrous conditions. In addition, these P(VDF-co-CTFE)-g-PHEA/IDA/H₃PO₄ membranes exhibited good mechanical properties (765 MPa of Young's modulus), and high thermal stability up to 250 °C, as determined by a universal testing machine (UTM) and thermal gravimetric analysis (TGA), respectively.     

Proton‐conducting polymer membrane based on sulfonated polystyrene microspheres and an amphiphilic polymer blend

A new type of amphiphic polymer blend comprising polystyrene (PS), polyethylene oxide (PEO) and microspheres of crosslinked polystyrene sulfonic acid (PSSA) was prepared by solution blending and followed by casting. Besides providing protons, PSSA plays a role in enhancing the miscibility of polystyrene (PS) and polyethylene oxide (PEO) according to the IR and the DSC studies. The resulting polymer blend is a proton electrolyte. The influence of the mixing extent between PS and PEO on the proton conductivity has been studied. It is also found that for those samples in which PEO and PS mix well, the hydrophobic PS component can effectively prevent water evaporation from the hydrophilic components at elevated temperatures, and therefore preserve the proton conductivity (10⁻⁴ S/cm) at the temperature as high as 80 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1530–1538, 2000     

Proton conducting grafted/crosslinked membranes prepared from poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) copolymer

Poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) (P(VDF‐co‐CTFE)) backbone was grafted with crosslinkable chains of poly(hydroxyl ethyl acrylate) (PHEA) and proton conducting chains of poly(styrene sulfonic acid) (PSSA) to produce amphiphilic P(VDF‐co‐CTFE)‐g‐P(HEA‐co‐SSA) graft copolymer via atom transfer radical polymerization (ATRP). Successful synthesis and microphase‐separated structure of the copolymer were confirmed by ¹H NMR, FT‐IR spectroscopy, and TEM analysis. Furthermore, this graft copolymer was thermally crosslinked with sulfosuccinic acid (SA) to produce grafted/crosslinked membranes. Ion exchange capacity (IEC) increased continuously with increasing SA contents but the water uptake increased up to 6 wt% of SA concentration, above which it decreased monotonically. The membrane also exhibited a maximum proton conductivity of 0.062 S/cm at 6 wt% of SA concentration, resulting from competitive effect between the increase of ionic groups and the degree of crosslinking. XRD patterns also revealed that the crystalline structures of P(VDF‐co‐CTFE) disrupted upon graft polymerization and crosslinking. These membranes exhibited good thermal stability at least up to 250°C, as revealed by TGA. Copyright © 2009 John Wiley & Sons, Ltd.     

Sulfonated poly(ether sulfone)s with binaphthyl units as proton exchange membranes for fuel cell application

Sulfonated poly(ether sulfone)s containing binaphthyl units (BNSHs) were successfully prepared for fuel cell application. BNSHs, which have very simple structures, were easily synthesized by postsulfonation of poly(1,1′‐dinaphthyl ether phenyl sulfone)s and gave tough, flexible, and transparent membranes by solvent casting. The BNSH membranes showed low water uptake compared to a typical sulfonated poly(ether ether sulfone) (BPSH‐40) membrane with a similar ion exchange capacity (IEC) value and water insolubility, even with a high IEC values of 3.19 mequiv/g because of their rigid and bulky structures. The BNSH‐100 membrane (IEC = 3.19 mequiv/g) exhibited excellent proton conductivity, which was comparable to or even higher than that of Nafion 117, over a range of 30–95% relative humidity (RH). The excellent proton conductivity, especially under low RH conditions, suggests that the BNSH‐100 membrane has excellent proton paths because of its high IEC value, and water insolubility due to the high hydrophobicity of the binaphthyl structure. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5827–5834, 2009     

Alternating copolymer based on sulfonamide‐substituted phenylmaleimide and vinyl monomers as polymer electrolyte membrane

The alternating copolymerization of phenylmaleimide (PMI) with a pendant sulfonamide acid group (sa‐PMI) and n‐butyl vinyl ether (BVE) as the aliphatic vinyl monomer afforded proton‐conducting polymer electrolytes—sa‐PMI‐BVEs—and their properties were compared with those of sa‐PMI‐STs that were synthesized from sa‐PMI and styrene. The ion exchange capacities (IECs) can be easily controlled by partly replacing sa‐PMI with unsubstituted PMI. sa‐PMI‐BVE is more flexible than sa‐PMI‐ST, and therefore, forms thin membranes even at high IECs, while sa‐PMI‐ST membranes are rigid and brittle. However, sa‐PMI‐BVE exhibits rather low thermal and oxidative stability. To realize polymer electrolyte membranes with reliable mechanical strength and a high IEC, gel‐filled membranes were prepared by polymerization in the presence of a small amount of a crosslinker, divinylbenzene, in porous polytetrafluoroethylene membranes. By using the gel‐filled membrane, H₂/O₂ fuel cells could be operated at 80 °C with reasonable performance. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013     

Highly sulfonated multiblock copoly(ether sulfone)s for fuel cell membranes

Highly sulfonated multiblock copoly(ether sulfone)s applicable to proton electrolyte fuel cells (PEFCs) were synthesized by the coupling reaction of corresponding hydroxyl‐ terminated oligomers in the presence of highly reactive decafluorobiphenyl (DFB) as a chain extender, followed by postsulfonation with concentrated sulfuric acid. Their molecular weights were reasonably high as determined by viscosity measurement (η_inh = 0.72–1.58 dL/g). It was also confirmed that postsulfonation selectively took place in hydrophilic segments to yield highly sulfonated multiblock copolymers (IEC = 1.90–2.75 mequiv/g). The resulting polymers gave transparent, flexible, and tough membranes by solution casting. The 4b membrane, as a representative sample, demonstrated good mechanical strength in the dry state regardless of high IEC value (2.75 mequiv/g). The 4a–c membranes with higher IEC values (IEC = 2.75–2.79 mequiv/g) maintained high water uptake (13.7–17.7 wt %) at 50% RH and it was still high (7.4–8.5 wt %) at 30% RH. Proton conductivity of all membranes at 80 °C and 95% RH was higher than that of Nafion 117. Furthermore, the 4a membrane showed high proton conductivity, comparable with Nafion 117 in the range of 50–95% RH, and maintained high proton conductivity (2.3 × 10^?3 S/cm) even at 30% RH. Finally, the surface morphology of the membrane was investigated by tapping mode atomic force microscopy, which showed well‐connected hydrophilic domains that could work as proton transportation channel. This phase separation and the high water uptake behavior probably contributed to high and effective proton conduction in a wide range of relative humidity. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2757–2764, 2010     

Locally sulfonated poly(ether sulfone)s with highly sulfonated units as proton exchange membrane

Novel locally sulfonated poly(ether sulfone)s with highly sulfonated units were successfully synthesized for fuel cell applications. Poly(ether sulfone)s were prepared by the nucleophilic substitution of bis(4‐fluorophenyl) sulfone with 1,2,4,5‐tetrakis([1,1′‐biphenyl]‐2‐oxy)‐3,6‐bis(4‐hydroxyphenoxy)benzene and bis(4‐hydroxyphenyl) sulfide, followed by oxidation using m‐chloroperoxybenzoic acid. The desired highly sulfonated units were easily introduced by postsulfonation and each one had ten sulfonic acid groups. The sulfonated polymers gave tough, flexible, and transparent membranes by solvent casting. The high contrast in polarity between highly sulfonated units and hydrophobic poly(ether sulfone) units enabled the formation of defined phase‐separated structures and well‐connected proton paths. The sulfonated polymers exhibited excellent proton conductivity over a wide range of relative humidities. The proton conductivity of the sulfonated polymer with an ion exchange capacity value of 2.38 mequiv/g was comparable to that of Nafion 117 even at 30% relative humidity. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3444–3453, 2009     

Synthesis and properties of amphoteric copolymer of 5‐vinyltetrazole and vinylbenzyl phosphonic acid

Amphoteric polymers have been studied for various applications such as separation of low molecular weight organic molecules from inorganic salt mixtures, selective ion transport, drug delivery through membranes of biological interest, separation of ionic drugs and proteins, and separation of alcohol and water. Typical amphoteric polymers consist of weak base and weak acid groups. In present study, the copolymerization of 5‐vinyltetrazole (VT) and diisopropyl‐p‐vinylbenzyl phosphate (DIPVBP) via free radical polymerization is studied. The reactivity ratio of VT and DIPVBP, which is calculated from Kelen‐Tudos plot, is 0.251 and 0.345, respectively. The amphoteric copolymer of VT and diisopropyl‐p‐vinylbenzyl phosphonic acid (poly(VT‐co‐VBPA)) is obtained from hydrolysis of the copolymer of VT and DIPVBP (poly(VT‐co‐DIPVBP)). Poly(VT‐co‐VBPA) is thermally stable under 190 °C. The anhydrous proton conductivity of amphoteric poly(VT‐co‐VBPA) can reach 1.54 × 10^‐4 S cm^?1 at 170 °C with an activation energy of 114.7 kJ mol^?1. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3486–3493