Enhancing the glass‐transition temperature of polyimide copolymers containing 2,2′‐bipyridine units by the coordination of nickel malenonitriledithiolate

Polyimide copolymers containing 2,2′‐bipyridine were synthesized and characterized. The glass‐transition temperatures (T_g's) of the polymers ranged from 260 to 300 °C. In contrast to most known organic chromophore‐containing polyimides, the polyimide copolymers in this study showed elevated T_g's (270–320 °C) after coordination with nickel malenonitriledithiolate inorganic chromophores. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 498–503, 2000     

Synthesis of polyphenylquinoxaline copolymers via aromatic nucleophilic substitution reactions of an A‐B quinoxaline monomer

A self‐polymerizable quinoxaline monomer (A‐B) has been synthesized and polymerized via aromatic nucleophilic substitution reactions. An isomeric mixture of self‐polymerizable quinoxaline monomers—2‐(4‐hydroxyphenyl)‐3‐phenyl‐6‐fluoroquinoxaline and 3‐(4‐hydroxyphenyl)‐2‐phenyl‐6‐fluoroquinoxaline—was polymerized in N‐methyl‐2‐pyrrolidinone (NMP) to afford high molecular weight polyphenylquinoxaline (PPQ) with intrinsic viscosities up to 1.91 dL/g and a glass‐transition temperature (T_g) of 251 °C. A series of comonomers was polymerized with A‐B to form PPQ/polysulfone (PS), PPQ/polyetherether ketone (PEEK), and PPQ/polyethersulfone (PES) copolymers. The copolymers readily obtained high intrinsic viscosities when fluorine was displaced in NMP under reflux. However, single‐electron transfer (SET) side reactions, which limit molecular weight, played a more dominant role when chlorine was displaced instead of fluorine. SET side reactions were minimized in the synthesis of PPQ/PS copolymers through mild polymerization conditions in NMP for longer polymerization times. Thus, the T_g's of PES (T_g = 220 °C), PEEK (T_g = 145 °C), and PS (T_g = 195 °C) were raised through the incorporation of quinoxaline units into the polymer. Copolymers with high intrinsic viscosities resulted in all cases, except in the case of PPQ/PEEK copolymers when 4,4′‐dichlorobenzophenone was the comonomer. © 2001 John Wiley & Sons, Inc. J Polym Sci A Part A: Polym Chem 39: 2037–2042, 2001     

Synthesis and properties of 4,4′-biphenyldicarboxylic acid and 2,6-naphthalenedicarboxylic acid

This article describes the synthesis and the properties of polyesters and copolyesters prepared from ethylene glycol, terephthalic acid, 4,4′ biphenyldicarboxylic acid (BDA), and 2,6-naphthlenedicarboxylic acid (NDA). The effect of incorporating varying levels of BDA and NDA on polyethylene terephthalate (PET) is described. Depending on the concentration, incorporation of BDA into PET leads to an improvement in glass transition temperature (T_g), strength, modulus, and barrier properties. Copolymers of PET containing up to about 50% BDA derived units are clear and have T_g's ranging from 85 to 105°C, making them suitable for applications where a high T_g along with clarity is important. Copolymers with higher BDA concentration are highly crystalline, with high rates of crystallization from the melt. Copolymerization of NDA with oligoethyleneterephthalate leads to copolymers that are generally amorphous. Crystallinity can be developed in copolymers with low concentration of NDA by thermal annealing. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3139–3146, 1999     

Synthesis and characterization of poly(arylene ether)s containing 6‐(4‐hydroxyphenyl)pyridazin‐3(2H)‐one or 6‐(4‐hydroxyphenyl)pyridazine moieties

A series of novel soluble pyridazinone‐ or pyridazine‐containing poly(arylene ether)s were prepared by a polycondensation reaction. The pyridazinone monomer, 6‐(4‐hydroxyphenyl)pyridazin‐3(2H)‐one ( 1 ), was synthesized from the corresponding acetophenone and glyoxylic acid in a simple one‐pot reaction. The pyridazinone monomer was successfully copolymerized with bisphenol A (BPA) or 1,2‐dihydro‐4‐(4‐hydroxyphenyl)phthalazin‐1(2H)‐one (DHPZ) and bis(4‐fluorophenyl)sulfone to form high‐molecular‐weight polymers. The copolymers had inherent viscosities of 0.5–0.9 dL/g. The glass‐transition temperatures (T_g's) of the copolymers synthesized with BPA increased with increasing content of the pyridazinone monomer. The T_g's of the copolymers synthesized from DHPZ with different pyridazinone contents were similar to those of the two homopolymers. The homopolymers showed T_g's from 202 to 291 °C by differential scanning calorimetry. The 5% weight loss temperatures in nitrogen measured by thermogravimetric analysis were in the range of 411–500 °C. 4‐(6‐Chloropyridazin‐3‐yl)phenol ( 2 ) was synthesized from 1 via a simple one‐pot reaction. 2 was copolymerized with 4,4′‐isopropylidenediphenol and bis(4‐fluorophenyl)sulfone to form high‐T_g polymers. The copolymers with less than 80 mol % pyridazinone or chloropyridazine monomers were soluble in chlorinated solvents such as chloroform. The copolymers with higher pyridazinone contents and homopolymers were not soluble in chlorinated solvents but were still soluble in dipolar aprotic solvents such as N‐methylpyrrolidinone. The soluble polymers could be cast into flexible films from solution. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3328–3335, 2006     

Synthesis of novel cyclic olefin polymers with excellent transparency and high glass‐transition temperature via gradient copolymerization of bulky cyclic olefin and cis‐cyclooctene

Novel cyclic olefin polymers (COPs) with excellent transparency and high glass‐transition temperature (T_g) synthesized from bulky norbornene derivative, exo‐1,4,4a,9,9a,10‐hexahydro‐9,10(1',2')‐benzeno‐l,4‐methanoanthracene (HBMN), and cis‐cyclooctene (COE) by ring‐opening metathesis copolymerization utilizing the “first‐generation Grubbs” catalyst, RuCl₂(PCy₃)₂(CHPh), and subsequent hydrogenation was reported herein. To get amorphous copolymers, it was of great importance to control the feed ratios and the polymerization time for gradient copolymerization. All these copolymers showed very high T_gs (141.1–201.2 °C), which varied with the content of HBMN. The films of the gradient copolymers with only one T_g were highly transparent. On the contrary, all the block copolymers synthesized through sequential addition showed two thermal transition temperatures, T_g and melt temperature (T_m), and the films of these block copolymers were opaque. The mechanical performances of the COPs were also investigated. It is the first report that transparent COP could be prepared from bulky norbornene derivative and monocyclic olefin. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3240–3249     

Breadth of glass transition temperature in styrene/acrylic acid block,random, and gradient copolymers: Unusual sequence distribution effects

Block, random, and gradient copolymers of styrene (S) and acrylic acid (AA) are synthesized by conventional or controlled radical polymerization, and their glass transition temperature (T_g) behaviors are compared. The location and breadth of the T_gs are determined using derivatives of differential scanning calorimetry heating curves. Each S/AA random copolymer exhibits one narrow T_g, consistent with a single phase of limited compositional nanoheterogeneity. Block copolymers exhibit two narrow T_gs originating from nanophase separation into ordered domains with nearly pure S or nearly pure AA repeat units. Each gradient copolymer exhibits a T_g response with a ～50–56 °C breadth that extends beyond the upper T_g of the block copolymers. For copolymers of similar composition, the maximum value in the gradient copolymer T_g response is consistent with that of a random copolymer, which has an enhanced T_g relative to poly(acrylic acid) due to more effective hydrogen bonding when AA units are separated along the chain backbone by S units. These results indicate that gradient copolymers with ordered nanostructures can be rationally designed, which exhibit broad glass transitions that extend to higher temperature than the T_gs observed with block copolymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2842–2849, 2007     

Synthesis of copolymers of poly(ether sulfone ether ketone ketone) and poly(ether ketone diphenyl ketone ether ketone ketone) by electrophilic Friedel–Crafts solution polycondensation

A new monomer, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl(BPOBDP), was synthesized via a two‐step synthetic procedure. A series of novel poly(ether sulfone ether ketone ketone)/poly(ether ketone diphenyl ketone ether ketone ketone) copolymers were prepared by electrophilic Friedel–Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of 4,4′‐diphenoxydiphenylsulfone (DPODPS) and 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP), in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers with 10–50 mol% DPODPS are semicrystalline and have remarkably increased T_gs over commercially available PEEK and PEKK. The copolymers with 40–50 mol% DPODPS had not only high T_gs of 170–172°C, but also moderate T_ms of 326–333°C, which are extremely suitable for melt processing. These copolymers have tensile strengths of 96.5–108.1 MPa, Young's moduli of 1.98–3.05 GPa, and elongations at break of 13–26% and exhibit excellent thermal stability and good resistance to acidity, alkali, and common organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.     

Pseudopoly(amino acid)s: Copolymerization of trans‐4‐hydroxy‐L‐proline and α‐hydroxy acids

A series of novel copolymers of trans‐4‐hydroxy‐L ‐proline (Hpr) and α‐ hydroxy acids [D,L ‐mandelic acid (DLMA) and D,L ‐lactic acid (DLLA)] were synthesized via direct melt copolymerization with stannous octoate as a catalyst. These new copolymers had pendant amine functional groups along the polymer backbone chain. The optimal reaction conditions for the synthesis of the copolymers were obtained with 4 wt % stannous octoate at 140 °C under vacuum for 16 h. The synthesized copolymers were characterized by IR spectrophotometry, proton nuclear magnetic resonance, differential scanning calorimetry, and Ubbelohde viscometry. The effects of the kinds of comonomers and the comonomer molar ratio on the polycondensation and glass‐transition temperature (T_g) were investigated. The T_g's of the copolymers shifted to lower temperatures with an increasing comonomer molar ratio. As expected, the T_g's of the N‐Z‐Hpr/DLMA copolymers were higher than the N‐Z‐Hpr/DLLA copolymers, the pendant groups on the monomers (N‐Z‐Hpr) became larger and more flexible, and the T_g's of the resulting polymers declined. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 724–731, 2001     

Poly(silarylene–siloxane)polyimides from allyl‐terminated oligoimides and hydride‐functional silarylene–siloxanes via hydrosilylation polymerization

This research was focused on the design and execution of new synthetic routes to low‐temperature‐curable poly(silarylene–siloxane)polyimides. The synthesis of individual oligoimide and silarylene–siloxane blocks was followed by hydrosilylation polymerization to produce crosslinked copolymers. The silarylene–siloxane and polyimide blocks were structurally characterized by IR and ¹H NMR spectroscopy and size exclusion chromatography. The high‐temperature resistance of the copolymers was evaluated through the measurement of heat distortion temperatures (T_HD's) via thermomechanical analysis and by the determination of the weight loss at elevated temperatures via thermogravimetric analysis. Glass‐transition temperatures (T_g's) of the silarylene–siloxane segments were measured by differential scanning calorimetry. Hydrosilylation curing was conducted at 60 °C in the presence of chloroplatinic acid (H₂PtCl₆). The copolymers displayed both high‐temperature resistance and low‐temperature flexibility. We observed T_g of the silarylene–siloxane segment as low as ?77 °C and T_HD of the polyimide segment as high as 323 °C. The influence of various oligoimide molecular weights on the properties of copolymers containing the same silarylene–siloxane was examined. The effect of various silarylene–siloxane molecular weights on the properties of copolymers containing the same oligoimide was also examined. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4922–4932, 2005     

Poly(methyl methacrylate) copolymers containing multiple,pendent plasticizing groups

New ether dimer (ED‐Eh) and diester (EHDE) derivatives of α‐(hydroxymethyl)acrylate, each having two 2‐ethylhexyl side chains, and an amine‐linked di(2‐ethylhexyl)acrylate (AL‐Eh), having three 2‐ethylhexyl side chains, were synthesized and (co)polymerized to evaluate the effects of differences in the structures of the monomers on final (co)polymer properties, particularly glass transition temperature, T_g. The free radical polymerizations of these monomers yielded high‐molecular–weight polymers. Cyclopolymer formation of ED‐Eh and AL‐Eh was confirmed by ¹³C NMR analysis and the cyclization efficiencies were found to be very high (～100%). Copolymers of ED‐Eh, EHDE, and AL‐Eh with methyl methacrylate (MMA) showed significant T_g decreases over poly(methyl methacrylate) (PMMA) due to 2‐ethylhexyl side groups causing “internal” plasticization. Comparison of the T_g's of the copolymers of 2‐ethylhexyl methacrylate, ED‐Eh, EHDE, and AL‐Eh with MMA revealed that the impacts of these monomers on depression of T_g's are identical with respect to the total concentration of the pendent groups. This is consistent with an earlier study involving copolymers of monomers comprising one and two octadecyl side groups with MMA. That is, the magnitude of decrease in T_g's was quantitatively related to the number of the 2‐ethylhexyl pendent groups in the copolymers rather than their placement on the same or randomly incorporated repeat units. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2302–2310, 2010     

Radical copolymerization of alkyl 2‐norbornene‐2‐carboxylate with alkyl acrylates: Facile incorporation of norbornane framework into poly(alkyl acrylate)s

Radical copolymerization of alkyl 2‐norbornene‐2‐carboxylates (alkyl = Me 1a , nBu 1b ) with alkyl acrylates (alkyl = ethyl, methyl, and n‐butyl) was investigated. Copolymerization of 1a,b with the alkyl acrylates initiated by 1,1′‐azobis (cyclohexane‐1‐carbonitrile) at 85 °C proceeded to give random copolymers, although the homopolymerization of 1a,b did not proceed efficiently under the same conditions. Typically, bulk copolymerization of 1a with ethyl acrylate in a feed ratio of 1:3 ([ 1a ]:[EA]) afforded a copolymer with M_n = 33,300 containing 19.4 mol % of 1a unit in the composition. An increase of T_g derived from the incorporation of the rigid norbornane framework was observed, although the extent of the temperature rise was rather moderate. The ternary radical copolymerization of 1a,b /alkyl acrylate/N‐phenylmaleimide proceeded to give copolymers with the three repeating units in the main chain. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4597–4605, 2007     

Synthesis of repeating sequence copolymers of lactic,glycolic, and caprolactic acids

Repeating sequence copolymers of poly(lactic‐co‐caprolactic acid) (PLCA), poly(glycolic‐co‐caprolactic acid) (PGCA), and poly(lactic‐co‐glycolic‐co‐caprolactic acid) (PLGCA) have been synthesized by polymerizing segmers with a known sequence in yields of 50–85% with M_ns ranging from 18–49 kDa. The copolymers exhibited well‐resolved NMR resonances indicating that the sequence encoded in the segmers used in their preparation is retained and that transesterification is minimal. The exact sequences allowed for unambiguous assignment of the NMR spectra, and these standards were compared with the data previously reported for random copolymers. The glass transition temperatures (T_gs) of the PLCA and PGCA copolymers were found to depend primarily on monomer ratio rather than sequence. Sequence dependent T_gs were, however, noted for the PLGCA polymers with 1:1:1 L:G:C ratios; poly LGC and poly GLC exhibited T_gs that differed by nearly 8 °C. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Synthesis and polymerization of new di‐octadecyl ester derivatives of α‐hydroxymethyl acrylate: A structure‐property correlation for their copolymers with methyl methacrylate

New ether dimer (ED‐Od) and diester (ODE) derivatives of α‐hydroxymethylacrylate, each having two octadecyl side chains, were synthesized and (co)polymerized to evaluate the effects of differences in the structures of the monomers on final (co)polymer properties, particularly glass transition temperature. The free radical polymerizations of both monomers yielded high‐molecular weight polymers. Cyclopolymer formation of ED‐Od was confirmed by ¹³C NMR analysis and the cyclization efficiency (0.95 or greater) was found to be as high as the cyclization efficiencies of the cyclopolymerizations of ether dimers of various alkyl α‐hydroxymethylacrylates synthesized previously. Copolymers of both ED‐Od and ODE with methyl methacrylate (MMA) showed significant T_g decreases over PMMA due to octadecyl side groups causing “internal” plasticization. Comparison of the T_g's of the copolymers of octadecyl methacrylate, ED‐Od and ODE with MMA revealed that the impacts of these monomers on depression of T_g's are identical. That is, the magnitude of decrease in T_g's was quantitatively related to the number of the octadecyl side groups in the copolymers rather than their placement on the same or randomly incorporated repeat units. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7785–7793, 2008     

Glass transition temperature of allyl methacrylate‐n‐butyl acrylate gradient copolymers in dependence on chemical composition and molecular weight

Glass transition temperatures (T_gs) of P(AMA‐co‐BA) copolymers and the corresponding homopolymers, where AMA is allyl methacrylate and BA is n‐butyl acrylate, obtained by means of atom transfer radical polymerization were measured using differential scanning calorimetry. Because of the (pseudoliving) nature of this polymerization technique an increase in molecular weight (MW) is produced as the reaction progresses, which gives rise to an increase in T_gs. This increment can be adequately described by the Fox–Flory's equation in both homopolymers. However, in the spontaneous gradient copolymers of P(AMA‐co‐BA), the expected increase in T_g with the augment of the monomer conversion is compensated by the enrichment of BA as the polymerization reaction progresses. These opposite effects with respect to the T_g values almost balance each other, and therefore no significant influence on the MW or on conversion is found. This fact establishes that T_gs can be used to describe the profile of these gradient copolymers, and can be theoretically determined because of its dependence on the molar fraction in the copolymer. From this dependence on chemical composition along with the experimental behavior, a prediction of the T_g variation with the MW was performed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1845–1855, 2007     

Structural modifications in imide-aryl ether phenylquinoxaline random copolymers

A rigid rod polyimide derived from biphenyldianhydride (BPDA) and p-phenylenediamine (PDA) was modified by the incorporation of diamines containing performed phenylquinoxaline and aryl ether linkages, and the morphology and mechanical properties of the resulting imide-aryl ether phenylquinoxaline copolymers were investigated. These phenylquinoxaline containing diamines, 1, 4-bis[6-(3-aminophenoxy)-3-phenyl-2-quinoxalinyl] benzene and 1, 4-bis[6-(4-aminophenoxy)-3-phenyl-2-quinoxalinyl] benzene, were prepared by a novel nucleophilic aromatic substitution reaction of 1,4-(6-fluoro-3-phenyl-2-quinoxalinyl) benzene with either 1, 3- or 1, 4-aminophenol in the presence of K₂CO₃, respectively. The diamines were utilized as co-monomers with BPDA and PDA to synthesize poly(amicacids.) Films were cast and cured (350°C) to effect imidization, affording films which showed high elongations and moduli. The copolymers with high phenylquinoxaline compositions displayed T_g's in the 300°C range, and the thermal stability of the copolymers was comparable to that of the parent polyimide. The copolymers also showed improved auto- or self-adhesion, particularly those which showed a T_g, allowing sufficient molecular motion for interdiffusion.     

Novel cyano-containing copolymers of vinyl esters for piezoelectric materials

The synthesis of a series of novel cyano-containing copolymers is described. Alternating copolymers of acrylonitrile with vinyl esters are obtained by increasing the electrophilic character of the nitrile monomers by complexation with zinc chloride. Copolymers of methyl and ethyl α-cyanoacrylates with vinyl esters are prepared using radical initiators in the presence of 7% acetic acid as inhibitor for anionic polymerization. The copolymers of methyl α-cyanoacrylate with the vinyl esters have T_g's above 140°C. Methyl vinylidene cyanide (MVCN) copolymerizes spontaneously with para-substituted styrenes to yield copolymers with high inherent viscosities and high T_g (160°C) and the copolymer of MVCN with vinyl acetate is also synthesized. The pyroelectric constants p for these polymers were measured and the values of p for the copolymers of vinyl acetate with methyl β,β-dicyanoacrylate, methyl α-cyanoacrylate, or MVCN were in the same range as the well-studied vinylidene cyanide/vinyl acetate copolymer. A higher concentration of dipoles generally results in higher T_g's and higher pyroelectric coefficients. © 1992 John Wiley & Sons, Inc.     

Property modification of poly(methyl methacrylate) through copolymerization with fluorinated aryl methacrylate monomers

Copolymers of methyl methacrylate (MMA) with 2,3,5,6‐tetrafluorophenyl methacrylate (TFPMA), pentafluorophenyl methacrylate (PFPMA), and 4‐trifluoromethyl‐2,3,5,6‐tetrafluorophenyl methacrylate (TFMPMA) were investigated. All the three systems showed a random copolymerization character. The composition, glass transition temperature (T_g), and refractive index of the copolymers obtained were studied. T_gs of TFPMA/MMA and PFPMA/MMA copolymers were found to deviate positively from the Gordon–Taylor equation. However, T_gs of TFMPMA/MMA copolymers were well fit with the Gordon–Taylor equation. These results indicated the existence of interaction between MMA and either TFPMA or PFPMA units in copolymers. This interaction resulted in the enhancement of the T_g of MMA polymers through the copolymerization with TFPMA and PFPMA. The refractive index and the light transmittance of copolymers were close to those of PMMA. Copyright © 2007 John Wiley & Sons, Ltd.     

Thermal and mechanical properties of random copolymers of diisopropyl fumarate with 1‐adamantyl and bornyl acrylates with high glass transition temperatures

We report the thermal, optical, and mechanical properties of random copolymers produced by radical copolymerizations of diisopropyl fumarate (DiPF) with 1‐adamantyl acrylate (AdA) and bornyl acrylate (BoA). The effects of a methylene spacer included in the main chain and bulky ester alkyl groups in the side chain on the copolymer properties are discussed. The produced copolymers are characterized by NMR and UV–vis spectroscopies, size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis (DMA). The copolymerization rate and the molecular weight of the copolymers increase with an increase in the acrylate content in feed during the copolymerization (M_w = 25–110 × 10³). The onset temperature of decomposition (T_d5) and the glass transition temperature (T_g) of the copolymers also increase according to the content of the acrylate units (T_d5 = 296–329 °C and 281–322 °C, T_g = 80–133 °C and 91–106 °C for the copolymers of DiPF with AdA and BoA, respectively). Transparent and flexible copolymer films are obtained by a casting method and their optical properties such as transparency and refractive indices are investigated (n_D = 1.478–1.479). The viscoelastic data of the copolymers are collected by DMA measurements under temperature control. The storage modulus decreases at a temperature region over the T_g value of the copolymers, depending on the structure and amount of the acrylate units. The sequence structure of the copolymers is analyzed based on monomer reactivity ratios and composition in order to discuss the copolymer properties related to chain rigidity and sequence length distribution. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 288–296     

Synthesis and polymerization of fluorinated monomers bearing a reactive lateral group. XIV. Radical copolymerization of vinylidene fluoride with methyl 1,1‐dihydro‐4,7‐dioxaperfluoro‐5,8‐dimethyl non‐1‐enoate

The radical copolymerization in solution of vinylidene fluoride (VDF; or 1,1‐difluoroethylene) with methyl 1,1‐dihydro‐4,7‐dioxaperfluoro‐5,8‐dimethyl non‐1‐enoate (MDP) initiated by di‐tert‐butyl peroxide is presented. Six copolymerization reactions were investigated with initial [VDF]₀/[MDP]₀ molar ratios of 35/65 to 80/20. Both of these comonomers copolymerized in this range of copolymerization. Moreover, these comonomers homopolymerized separately under these conditions. The copolymer compositions of these random copolymers were calculated by means of ¹⁹F NMR spectroscopy, which allowed the quantification of the respective amounts of each monomeric unit in the copolymers. The Tidwell–Mortimer method was used for the assessment of the reactivity ratios (r_i) of both comonomers, which showed a higher incorporation of MDP in the copolymers (r_MDP = 2.41 ± 2.28 and r_VDF = 0.38 ± 0.21 at 120 °C). The Alfrey–Price Q and e values of the trifluoroallyl monomer MDP were calculated to be 0.024 (from Q_VDF = 0.008) or 0.046 (from Q_VDF = 0.015) and 0.70 (vs e_VDF = 0.40) or 0.80 (vs e_VDF = 0.50), respectively, indicating that MDP was an electron‐accepting monomer. The thermal properties of these fluorinated copolymers were also determined. Except for those containing a high amount of VDF, the copolymers were amorphous. Each showed one glass‐transition temperature (T_g) only, and with known laws of T_g's, T_g of the MDP homopolymer was assessed. It was compared to that obtained from the direct radical homopolymerization of MDP and discussed. Indeed, these two values were close (T_g = ?3 °C). Thermogravimetric analyses were performed, and they showed that the copolymers were rather thermostable because the thermal degradation occurred at 280 °C. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3109–3121, 2003     

Oxyethylene copolymers with chloromethyl and (alkylthio)methyl or (alkylsulfonyl)methyl side groups: Syntheses and Tg/composition relationships

New classes of copolymers, poly[oxy(chloromethyl)ethylene]/poly[oxy-((alkylthio)methyl)ethylene] copolymers (CE-ATEs), poly[oxy((alkylthio)methyl)-ethylene]s (ATEs), poly[oxy(chloromethyl)ethylene]/poly[oxy((alkylsulfonyl)meth-yl)ethylene] copolymers (CE-ASEs), and poly[oxy((alkylsulfonyl)methyl)ethylene]s (ASEs) have been made for the first time. The thioether-containing polymers (CE-ATEs and ATEs) were synthesized by reacting poly[oxy(chloromethyl)ethylene] (CE, poly(epichlorohydrin)) with different amounts of sodium alkanethiolates. The sulfone-containing polymers (CE-ASEs and ASEs) were synthesized by oxidizing the CE-ATEs and ATEs using m-chloroperoxybenzoic acid. The Fox equation, a linear relationship, fit the T_g/composition data for most CE-ATEs. The T_g's of the CE-ASEs showed positive deviations from those calculated using the Fox equation. The Johnston equation, in which steric and/or polar interactions between dissimilar monomeric units are considered by using T_gAB (the T_g of the AB or BA dyad), fit the T_g/composition data for all copolymers in this study. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36 : 495–504, 1998