Matrix‐assisted laser desorption/ionization time‐of‐flight analysis of the copolymerization reaction of an expanding monomer with a diepoxide

In search of a composite with low stress and low shrinkage properties, this study includes matrix‐assisted laser desorption/ionization time‐of‐flight analysis of the photoinitiated cationic polymerization between an expanding monomer [1,5,7,11‐tetraoxaspiro[5.5]undecane (TOSU)] and a diepoxide [bisphenol A diglycidyl ether (BADGE)]. Past studies using NMR and differential scanning calorimetry analyses concluded copolymerization indirectly on the basis of deviations from homopolymer product data. This is the first study to provide direct evidence of copolymerization between these species. Unlike previous research, this study enables the identification of the TOSU homopolymer and the absence of the BADGE homopolymer, suggesting initial cationic activation of TOSU. In addition to peaks that correspond to the presumed mechanism for six‐membered TOSU polymerization, many peaks have a net gain or loss of cyclic carbonate in support of a new polymerization mechanism participating in the reaction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5962–5970, 2005     

Preparation of novel poly(ethylene oxide‐co‐glycidol)‐graft‐poly(ε‐caprolactone) copolymers and inclusion complexation of the grafted chains with α‐cyclodextrin

A well‐defined comblike copolymer of poly(ethylene oxide‐co‐glycidol) [(poly(EO‐co‐Gly)] as the main chain and poly(ε‐caprolactone) (PCL) as the side chain was successfully prepared by the combination of anionic polymerization and ring‐opening polymerization. The glycidol was protected by ethyl vinyl ether to form 2,3‐epoxypropyl‐1‐ethoxyethyl ether (EPEE) first, and then ethylene oxide was copolymerized with EPEE by an anionic mechanism. The EPEE segments of the copolymer were deprotected by formic acid, and the glycidol segments of the copolymers were recovered after saponification. Poly(EO‐co‐Gly) with multihydroxyls was used further to initiate the ring‐opening polymerization of ε‐caprolactone in the presence of stannous octoate. When the grafted copolymer was mixed with α‐cyclodextrin, crystalline inclusion complexes (ICs) were formed, and the intermediate and final products, poly(ethylene oxide‐co‐glycidol)‐graft‐poly(ε‐caprolactone) and ICs, were characterized with gel permeation chromatography, NMR, differential scanning calorimetry, X‐ray diffraction, and thermogravimetric analysis in detail. The obtained ICs had a channel‐type crystalline structure, and the ratio of ε‐caprolactone units to α‐cyclodextrin for the ICs was higher than 1:1. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3684–3691, 2006     

Amphiphilic block and statistical copolymers with pendant glucose residues: Controlled synthesis by living cationic polymerization and the effect of copolymer architecture on their properties

Amphiphilic block and statistical copolymers of vinyl ethers (VEs) with pendant glucose residues were synthesized by the living cationic polymerization of isobutyl VE (IBVE) and a VE carrying 1,2:5,6‐di‐O‐isopropylidene‐D ‐glucose (IpGlcVE), followed by deprotection. The block copolymer was prepared by a two‐stage sequential block copolymerization, whereas the statistical copolymer was obtained by the copolymerization of a mixture of the two monomers. The monomer reactivity ratios estimated with the statistical copolymerization were r₁ (IBVE) = 1.65 and r₂ (IpGlcVE) = 1.15. The obtained statistical copolymers were nearly uniform with the comonomer composition along the main chain. Both the block and statistical copolymers had narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight ∼ 1.1). Gel permeation chromatography, static light scattering, and spin–lattice relaxation time measurements in a selective solvent revealed that the block copolymer formed multimolecular micelles, possibly with a hydrophobic poly(IBVE) core and a glucose‐carrying poly(VE) shell, whereas the statistical copolymer with nearly the same molecular weight and segment composition was molecularly dispersed in solution. The surface properties of the solvent‐cast films of the block and statistical copolymer were also investigated with the contact‐angle measurement. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 459–467, 2001     

Anionic polymerization of cyclic ester and amide in miniemulsion: Synthesis and characterization of poly(ε‐caprolactone) and poly(ε‐caprolactone‐co‐ε‐caprolactam) nanoparticles

For the first time, poly(ε‐caprolactone) and poly(ε‐caprolactone‐co‐ε‐caprolactam) nanoparticles were successfully obtained by anionic polymerization of ε‐caprolactone and anionic copolymerization of ε‐caprolactone with ε‐caprolactam, respectively, in heterophase by the miniemulsion technique. After polymerization the resulting dispersions are stable for hours in case of the pure polyester and days for the copolymer. The syntheses were carried out with different continuous phases, amounts of surfactant, initiator, and monomers. The influence of the reaction parameters on the molecular weight of the polymers and on colloidal characteristics like size and morphology of the nanoparticles were studied by dynamic light scattering, gel permeation chromatography, differential scanning calorimetry, nuclear magnetic resonance, and Fourier transform infrared spectroscopy. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Isothiourea‐based lewis pairs for homopolymerization and copolymerization of 2,2‐dimethyltrimethylene carbonate with ε‐caprolactone and ω‐pentadecalactone

In this study, the homopolymerization of 2,2‐dimethyltrimethylene carbonate (DTC) and its copolymerizations with ε‐caprolactone (CL) were carried out in detail using the isothiourea‐based Lewis pairs comprised 2,3,6,7‐tetrahydro‐5H‐thiazolo(3,2‐a)pyrimidine and magnesium halides (MgX₂) with benzyl alcohol (BnOH) as the initiator. The copolymerization of DTC and CL via one‐pot addition produced randomly sequenced copolymers. On the other hand, a well‐defined linear poly(ε‐caprolactone)–block–poly(2,2‐dimethyltrimethylene carbonate) (PCL‐b‐PDTC) diblock copolymer was prepared by simple sequential ring‐opening polymerization of CL and DTC. In addition, poly(ω‐pentadecalactone)–block–PDTC diblock copolymer was successfully prepared by the same strategy. Moreover, PDTC–poly(ethylene glycol) (PEG)–PDTC triblock copolymer was synthesized in the presence of PEG 2000. The effects of different polymerization conditions on the polymerization reactions have been systematically discussed. The resulting polymers were characterized by the ¹H and ¹³C NMR spectra, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐ToF MS). The block copolyester structures were confirmed by the ¹³C NMR spectroscopy and DSC characterizations. These results indicated that the supposed mechanism was a dual catalytic mechanism. The proposed mechanism involved activation of the monomer via coordination to the MgX₂, and the initiator alcohol was deprotonated by base. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2349–2355     

Living copolymerization of ethylene/1‐octene with fluorinated FI‐Ti catalyst

Living copolymerization of ethylene and 1‐octene was carried out at room temperature using the fluorinated FI‐Ti catalyst system, bis[N‐(3‐methylsalicylidene)‐2,3,4,5,6‐pentafluoroanilinato] TiCl₂/dried methylaluminoxane, with various 1‐octene concentrations. The comonomer incorporation up to 32.7 mol % was achieved at the 1‐octene feeding ratio of 0.953. The living feature still retained at such a high comonomer level. The copolymer composition drifting was minor in this living copolymerization system despite of a batch process. It was found that the polymerization heterogeneity had a severe effect on the copolymerization kinetics, with the apparent reactivity ratios in slurry significantly different from those in solution. The reactivity ratios were nearly independent of polymerization temperature in the range of 0–35 °C. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Stabilizer‐free dispersion copolymerization of maleic anhydride and vinyl acetate. I. Effects of principal factors on microspheres

A novel dispersion copolymerization of maleic anhydride (MAn) and vinyl acetate (VAc) without adding stabilizer is developed, which gives uniform copolymer microspheres with tunable sizes. Some principal factors affecting the microspheres, such as reaction time, monomer concentration and feed ratio, reaction media, and cosolvent, were investigated. It was found that the stabilizer‐free dispersion copolymerization of MAn and VAc is a rapid process, and the particle size grows in accordance with the evolution of polymerization. The chemical composition of the copolymer microspheres was characterized by FT‐IR and ¹³C NMR spectroscopies. Over a wide range of monomer concentrations, the microspheres can always be formed and stably dispersed, with uniform sizes ranging from 180 nm to 740 nm. The yield of copolymer microspheres reaches a maximum at 1:1 feed ratio of MAn to VAc, owing to the alternating copolymerization between the binary monomers by a known charge‐transfer‐complex mechanism. However, the diameter of microspheres drastically increases when MAn content is enhanced. Only some specific alkyl ester solvents, such as n‐butyl acetate, isobutyl acetate, n‐amyl acetate, are desirably fit for this unique stabilizer‐free dispersion polymerization. Furthermore, we found that when some acetone is added as a cosolvent, the copolymer microspheres can still be formed, with much larger diameters. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3760–3770, 2005     

Synthesis and enzymatic degradation of 2‐methylene‐1,3‐dioxepane and methyl acrylate copolymers

Copolymers of 2‐methylene‐1,3‐dioxepane (MDO) and methyl acrylate (MA) containing ester units both in the backbone and as pendant groups were synthesized by free‐radical copolymerization. The influence of reaction conditions such as the polymerization time, temperature, initiator concentration, and comonomer feed ratio on the yield, molecular weight, and copolymer composition was investigated. The structure of the copolymers was confirmed by ¹H NMR, ¹³C NMR, and IR spectroscopy. Differential scanning calorimetry indicated that the copolymers had a random structure. An NMR study showed that hydrogen transfer occurred during the copolymerization. The reactivity ratios of the comonomers were r_MDO = 0.0235 and r_MA = 26.535. The enzymatic degradation of the copolymers obtained was carried out in the presence of proteinase K or a crude enzyme extracted from earthworms. The experimental results showed that the higher ester molar percentage in the backbone caused a faster degradation rate. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2898–2904, 2003     

Random copolymerization of l‐lactide and ε‐caprolactone by aluminum alkoxide complexes supported by N2O2 bis(phenolate)‐amine ligands

The bowl‐shaped aluminum alkoxide complexes bearing N₂O₂ bis(phenolate)‐amine ligands having different side arms as pyridine ( 1 ), dimethyl amine ( 2 ), and diethyl amine ( 3 ) were shown to be highly efficient and well behaved in the homopolymerization and copolymerization of l ‐lactide (LA) and ε‐caprolactone (ε‐CL) at 100 °C. The rates of copolymerization are similar for Complexes 1 – 3 where nearly full conversions were achieved in 60 h for [LA]:[CL]:[Al] ratio of 50:50:1. The minor adjustment of the side arms of the Catalysts 1 – 3 gave profound differences in the LA/ε‐CL copolymer sequences where tapered, gradient, and highly random structures were obtained in one system, respectively. The chelation of LA to Al metal after ring‐opening process and suitable steric hindrance of the side arms were believed to participate and saturate the aluminum metal centers giving different copolymer structures. The random LA/ε‐CL copolymer structure was confirmed by nuclear magnetic resonance and differential scanning calorimetry analysis. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1635–1644     

Properties of well‐defined alternating and random copolymers of methacrylates and styrene prepared by controlled/living radical polymerization

The physical properties of well‐defined alternating copolymers poly(methyl methacrylate‐alt‐styrene) and poly(n‐butyl methacrylate‐alt‐styrene), prepared by reversible addition–fragmentation chain transfer polymerization in the presence of Lewis acids, were investigated with differential scanning calorimetry, wide‐angle X‐ray scattering, and dynamic mechanical measurements. The properties were compared with those of random copolymers of the same overall composition and the corresponding homopolymers. Wide‐angle X‐ray scattering data showed that the alternating copolymers possessed a more regular comonomer sequence than the random copolymers. The thermomechanical properties of alternating copolymers and random copolymers were quite similar and typical for amorphous polymers, but in one of the cases studied the glass‐transition temperature for alternating copolymer was remarkably higher than for the random copolymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3440–3446, 2005     

Synthesis and cationic ring‐opening polymerization of oxetane monomer containing five‐membered cyclic carbonate moiety via highly chemoselective addition of CO2

The bicyclic amidinium iodide effectively catalyzed the reaction of carbon dioxide and the epoxy‐containing oxetane under ordinary pressure and mild conditions with high chemoselectivity to give the corresponding oxetane monomer containing five‐membered cyclic carbonate quantitatively. The cationic ring‐opening polymerization of the obtained monomer by boron trifluoride diethyl ether proceeded to give linear polyoxetane bearing five‐membered cyclic carbonate pendant group in high yield. The molecular weight of the polyoxetane was higher than that of polyepoxide obtained by the cationic ring‐opening polymerization of epoxide monomer containing five‐membered cyclic carbonate. The cyclic carbonate functional crosslinked polyoxetanes were also synthesized by the cationic ring‐opening copolymerization of cyclic carbonate having oxetane and commercially available bisoxetane monomers. Analyses of the resulting polyoxetanes were performed by proton nuclear magnetic resonance, size exclusion chromatography, thermogravimetric analysis, and differential scanning calorimetry. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2606–2615     

Poly(N‐phenylmaleimide‐co‐acrylic acid)–copper(II) and poly(N‐phenylmaleimide‐co‐acrylic acid)–cobalt(II) complexes: Synthesis,characterization, and thermal behavior

The free‐radical copolymerization of N‐phenylmaleimide (N‐PhMI) with acrylic acid was studied in the range of 25–75 mol % in the feed. The interactions of these copolymers with Cu(II) and Co(II) ions were investigated as a function of the pH and copolymer composition by the use of the ultrafiltration technique. The maximum retention capacity of the copolymers for Co(II) and Cu(II) ions varied from 200 to 250 mg/g and from 210 to 300 mg/g, respectively. The copolymers and polymer–metal complexes of divalent transition‐metal ions were characterized by elemental analysis, Fourier transform infrared, ¹H NMR spectroscopy, and cyclic voltammetry. The thermal behavior was investigated with differential scanning calorimetry (DSC) and thermogravimetry (TG). The TG and DSC measurements showed an increase in the glass‐transition temperature (T_g) and the thermal stability with an increase in the N‐PhMI concentration in the copolymers. T_g of poly(N‐PhMI‐co‐AA) with copolymer composition 46.5:53.5 mol % was found at 251 °C, and it decreased when the complexes of Co(II) and Cu(II) at pHs 3–7 were formed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4933–4941, 2005     

Controllability of radical copolymerization of maleimide and ethyl α‐(n‐propyl)acrylate using 1,1,2,2‐tetraphenyl‐1,2‐bis(trimethylsilyloxy) ethane as initiator

The radical copolymerization of maleimide (MI) and ethyl α‐propylacrylate was performed using 1,1,2,2‐tetraphenyl‐1,2‐bis(trimethylsilyloxy) ethane (TPSE) as initiator. The whole copolymerization process might be divided into two stages: in the first stage, the copolymerization was carried out on the common radical mechanism, the molecular weight of the copolymer increased rapidly in much lower conversion (< 85%), and did not depend on the polymerization time and conversion; in the second stage, molecular weight of the copolymer increased linearly with the conversion and the polymerization time. It was found, however, when the conversion was higher than a certain value, for example, more than 36%, the molecular weight of the copolymer was nearly unchangeable with the polymerization time and the molecular weight distribution was widened. The effect of reaction conditions on copolymerization was discussed and the reactivity ratios were calculated by the Kelen–Tudos method, the values were r_MI = 0.13 ± 0.03, r_EPA = 0.58 ± 0.06 for TPSE system and r_MI = 0.12 ± 0.03, r_EPA = 0.52 ± 0.06 for AIBN system. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2872–2878, 2000     

Synthesis of surfactant‐free carbon nanotube/poly(styrene‐co‐acrylamide) by dynamic interfacial emulsion polymerization under sonication

This paper describes a study on emulsifier‐free ultrasonically assisted in‐situ copolymerization method of acrylamide and styrene in the presence of CNT, resulting in stable and uniform dispersions. The dispersions prepared were found stable for several months. Thermogravimetric analysis (TGA) curves and conversion measurements provided an insight regarding the polymerization mechanism and the nanocomposites structure. Films prepared of the polymerization products resulted in some clear and transparent coatings. The polymerization method described is simple and very fast compared with the other literature reported methods. TGA was extensively used as an analytical tool for determination of the composition of acrylamide–styrene copolymers. TGA and differential scanning calorimetry indicate that the polymerization product is largely a poly(styrene‐co‐acrylamide), where the acrylamide fraction is attached to the CNT surfaces. The copolymer produced, with and without CNT, is essentially a block copolymer, where each block contains small amounts of the other comonomer. To the authors' best knowledge, this report is the first one describing the production of stable dispersions of CNT in surfactant‐free poly(styrene‐co‐acrylamide) emulsion. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis of biodegradable copolymers with low‐toxicity zirconium compounds. IV. Copolymerization of glycolide with trimethylene carbonate and 2,2‐dimethyltrimethylene carbonate: Microstructure analysis of copolymer chains by high‐resolution nuclear magnetic resonance spectroscopy

The results of the copolymerization of glycolide with cyclic trimethylene carbonate and 2,2‐dimethyltrimethylene carbonate are described. The copolymerization was conducted in the presence of low‐toxicity zirconium(IV) acetylacetonate as an initiator. With this kind of initiator, the composition of the comonomer units in the copolymer chains was assumed to be obtained with high efficiency. Despite significant differences in the comonomer reactivity, in copolymers containing comparable amounts of glycolidyl and carbonate sequences, highly randomized chain structures were observed. This effect resulted from strong intermolecular transesterification that proceeded during the studied copolymerization and caused glycolidyl microblock randomization. The assignment of the spectral NMR lines to appropriate comonomer sequences of polymeric chains was performed in the region of methylene protons of glycolidyl units in ¹H NMR spectra of the copolymers and in the carbonyl region of carbon spectra. The equations were formulated for a detailed characterization of the obtained copolymer chains, the average lengths of the blocks, and the transesterification and randomization coefficients. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 98–114, 2006     

Heterograft copolymers of poly(ε‐caprolactone) prepared by combination of ATRA “grafting onto” and ATRP “grafting from” processes

This paper aims at reporting on the synthesis of a heterograft copolymer by combining the “grafting onto” process based on atom transfer radical addition (ATRA) and the “grafting from” process by atom transfer radical polymerization (ATRP). The statistical copolymerization of ε‐caprolactone (εCL) and α‐chloro‐ε‐caprolactone (αClεCL) was initiated by 2,2‐dibutyl‐2‐stanna‐1,3‐dioxepane (DSDOP), followed by ATRA of parts of the chlorinated units of poly(αClεCL‐co‐εCL) on the terminal double bond of α‐MeO,ω‐CH₂?CH? CH₂? CO₂‐poly(ethylene oxide) (PEO). The amphiphilic poly(εCL‐g‐EO) graft copolymer collected at this stage forms micelles as supported by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The unreacted pendant chloro groups of poly(εCL‐g‐EO) were used to initiate the ATRP of styrene with formation of copolymer with two populations of randomly distributed grafts, that is PEO and polystyrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6015–6024, 2006     

Copper(0)‐mediated radical copolymerization of vinyl acetate and acrylonitrile in DMSO at ambient temperature

In this work, Cu(0)‐mediated radical copolymerization of vinyl acetate (VAc) and acrylonitrile (AN) was explored. The polymerization was carried out at 25°C with 2,2′‐bipyridine as ligand and dimethyl sulfoxide as solvent. The copolymerization proceeded smoothly producing moderately controlled molecular weights at low VAc feed ratios. The high VAc feed ratios generated low polymerization rate and poorly controlled molecular weights. FTIR, ¹H NMR, and differential scanning calorimetry confirmed the successful obtaining of the copolymers. Based on ¹H NMR spectra, the reactivity ratios of VAc and AN were calculated to be 0.003 and 1.605, respectively. This work conveyed the first example for the Cu(0)‐mediated radical polymerization of AN and VAc, wherein VAc cannot be homopolymerized by Cu(0)‐mediated radical polymerization technique. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Stimuli‐responsive reversible physical networks. I. Synthesis and physical network properties of amphiphilic block and random copolymers with long alkyl chains by living cationic polymerization

The living cationic polymerization of octadecyl vinyl ether (ODVE) was achieved with an 1‐(isobutoxy)ethyl acetate [CH₃CH(OiBu)OCOCH₃]/EtAlCl₂ initiating system in hexane in the presence of an added weak Lewis base at 30 °C. In contrast to conventional polymers, poly(octadecyl vinyl ether) underwent upper‐critical‐solution‐temperature‐type phase separation in various solvents, such as hexane, toluene, CH₂Cl₂, and tetrahydrofuran, because of the crystallization of octadecyl chains. Amphiphilic block and random copolymers with crystallizable substituents of ODVE and 2‐methoxyethyl vinyl ether (MOVE) were synthesized via living cationic polymerization under similar conditions. Aqueous solutions of the copolymers yielded physical gels upon cooling because of strong interactions between ODVE units, regardless of the copolymer structure. The product gels, however, exhibited different viscoelastic properties: A 20 wt % solution of a block copolymer (400/20 MOVE/ODVE) became a soft physical gel that behaved like a typical gel, whereas the corresponding random copolymer gave a transparent but stiff gel with a certain relaxation time. Differential scanning calorimetry analysis confirmed that the crystalline–amorphous transition of the octadecyl chains was a key step for inducing such physical gelation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1155–1165, 2005     

Synthesis and characterization of copolyperoxides of indene with styrene, α‐methylstyrene,and α‐phenylstyrene

The oxidative copolymerization of indene with styrene, α‐methylstyrene, and α‐phenylstyrene is investigated. Copolyperoxides of different compositions have been synthesized by the free‐radical‐initiated oxidative copolymerization of indene with vinyl monomers. The compositions of the copolyperoxides obtained from the ¹H and ¹³C NMR spectra have been used to determine the reactivity ratios of the monomers. The reactivity ratios indicate that indene forms an ideal copolyperoxide with styrene and α‐methylstyrene and alternating copolyperoxides with α‐phenylstyrene. Thermal degradation studies via differential scanning calorimetry and electron‐impact mass spectroscopy support the alternating peroxide units in the copolyperoxide chain. The activation energy for thermal degradation suggests that the degradation is dependent on the dissociation of the peroxide (? O? O? ) bonds in the backbone of the copolyperoxide chain. Their flexibility has been examined in terms of the glass‐transition temperature. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2004–2017, 2002     

Novel amorphous perfluorocopolymeric system: Copolymers of perfluoro‐2‐methylene‐1,3‐dioxolane derivatives

Perfluorotetrahydro‐2‐methylene‐furo[3,4‐d][1,3]dioxole (monomer I ) and perfluoro‐2‐methylene‐4‐methoxymethyl‐1,3‐dioxolane (monomer II ) are soluble in perfluorinated or partially fluorinated solvents and readily polymerize in solution or in bulk when initiated by a free‐radical initiator, perfluorodibenzoyl peroxide. The copolymerization parameters have been determined with in situ ¹⁹F NMR measurements. The copolymerization reactivity ratios are r _I = 1.80 and r _II = 0.80 in 1,1,2‐trichlorotrifluoroethane at 41 °C and r _I = 0.97 and r _II = 0.85 for the bulk polymerization. These data show that this copolymerization pair has a good copolymerization tendency and yields nearly ideal random copolymers. The copolymers have only one glass‐transition temperature from 101 to 168 °C, depending on the copolymer compositions. Melting endotherms have not been observed in their differential scanning calorimetry traces, and this indicates that all the copolymers with different compositions are completely amorphous. These copolymers are thermally stable (the initial decomposition temperatures are higher than 350 °C under an N₂ atmosphere) and have low refractive indices and high optical transparency from UV to near‐infrared. Copolymer films prepared by casting were flexible and tough. These properties make the copolymers ideal candidates as optical and electrical materials. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1613–1618, 2006