Ring‐opening polymerization of ε‐caprolactone via the bismuth‐2‐mercaptoethanol complex

A complex consisting of one Bi³⁺ ion and two 2‐mercaptoethanol units (BiME₂) was used as initiator for the ring‐opening polymerization of ε‐caprolactone in bulk. A kinetic comparison showed that BiME₂ is as reactive as initiator as Sn‐octanoate and more reactive than Bi‐hexanoate. The difference to BiHex₃ decreased at higher temperatures and upon addition of an alcohol as coinitiator. When tetra(ethylene glycol) was used as coinitiator, it was completely incorporated into the poly(εCL) chain, so that telechelic polylactones having two OH‐endgroups were formed. In the absence of a coinitiator, 2‐mercaptoethanol or its disulfide were incorporated in the form of ester groups. Furthermore, it was found by MALDI‐TOF mass spectrometry that small amounts of cyclic oligolactones (detected up to a degree of polymerization of 17) were formed under all reaction conditions. Higher temperatures and longer times favored a higher content of cycles. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3175–3183, 2006     

Cationic ring‐opening polymerization of ϵ‐thionocaprolactone: Selective formation of polythioester

Cationic ring‐opening polymerization of ϵ‐thionocaprolactone was examined. The corresponding polythioester with the number‐average molecular weight (M_n ) of 57,000 was obtained in the polymerization with 1 mol % of BF₃ · OEt₂ as an initiator in CH₂Cl₂ at 28 °C for 5 h with quantitative monomer conversion. The M_n of the polymer increased with the solvent polarity and monomer‐to‐initiator ratio. No polymerization took place below −30 °C, and the monomer conversion and M_n of the polymer increased with the temperature in the range of −15 to 28 °C. The increase of initial monomer concentration was effective to improve the monomer conversion and the M_n of the obtained polymer. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4057–4061, 2000     

Syntheses of trimethoxysilyl‐endcapped polylactones via 3‐mercaptopropyl trimethoxysilane

Monofunctional polylactones were prepared by Bu₂Sn(OMe)₂‐initiated ring‐opening polymerization of ε‐caprolactone (εCL) followed by acylation with bromoacetylbromide. Telechelic polylactones and polylactides were prepared via ring‐expansion polymerization with 2,2‐dibutyl‐2‐stanna‐1,3‐dioxepane (DSDOP) or 2,2‐dibutyl‐2‐stanna‐pentaoxacyclotridecane (Bu₂SnTEG) as cyclic initiator. In situ combination of the polymerization with condensation by means of bromoacetylbromide yielded polylactones having bromoacetate endgroups. These endgroups were subjected to nucleophilic substitution with 3‐mercaptopropyl trimethoxysilane (3‐MPTMS). Analogous experiments were conducted with dl‐lactide. The telechelic trimethoxysilyl‐endcapped polylactones were characterized by viscosity, ¹H and ¹³C NMR‐spectroscopy, and MALDI‐TOF mass spectrometry. The mass spectra revealed small amounts of cyclic oligolactones as byproducts in all samples. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3667–3674, 2005     

Synthesis of a new monomer N′‐(β‐methacryloyloxyethyl)‐2‐pyrimidyl‐(p‐benzyloxycarbonyl)aminobenzenesulfonamide and its copolymerization with N‐phenyl maleimide

The new monomer N′‐(β‐methacryloyloxyethyl)‐2‐pyrimidyl‐(p‐benzyloxy‐ carbonyl)aminobenzenesulfonamide (MPBAS) (M₁) is synthesized using sulfadiazine as parent compound. It could be homopolymerized and copolymerized with N‐phenyl maleimide (NPMI) (M₂) by radical mechanism using AIBN as initiator at 60 °C in dimethylformamide. The new monomer MPBAS and polymers were identified by IR, element analysis and ¹H NMR in detail. The monomer reactivity ratios in copolymerization were determined by YBR method, and r₁ (MPBAS) = 2.39 ± 0.05, r₂ (NPMI) = 0.33 ± 0.02. In the presence of ammonium formate, benzyloxycarbonyl groups could be broken fluently from MPBAS segments of copolymer by catalytic transfer hydrogenation, and the copolymer with sulfadiazine side groups are recovered. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2548–2554, 2000     

Chain‐growth condensation polymerization approach to synthesis of well‐defined polybenzoxazole: Importance of higher reactivity of 3‐amino‐4‐hydroxybenzoic acid ester compared to 4‐amino‐3‐hydroxybenzoic acid ester

Application of chain‐growth condensation polymerization (CGCP) to obtain well‐defined polybenzoxazole (PBO) was examined. CGCP of both phenyl 3‐{(2‐methoxyethoxy)methoxy (MEM‐oxy)}‐4‐(octylamino)benzoate ( 1b ) (para‐substituted monomer) and phenyl 4‐MEM‐oxy‐3‐(octylamino)benzoate ( 3b ) (meta‐substituted monomer) was examined in the presence of metal disilazide base and phenyl 4‐nitro‐ or methylbenzoate 2 as an initiator. Polymerization of the latter monomer, but not the former, afforded polymer with controlled molecular weight based on the feed ratio of monomer to initiator and with a narrow molecular weight distribution. Accordingly, monomer 3c , in which the octyl group on the amino nitrogen of 3b was replaced with a 4‐(octyloxy)benzyl (OOB) group, was polymerized in the presence of lithium 1,1,1,3,3,3‐hexamethyldisilazide (LiHMDS), phenyl 4‐methylbenzoate ( 2b ), and LiCl in THF at 0 °C to yield poly 3c with well‐defined molecular weight (M_n = 4520–9080) and low polydispersity (M_w/M_n ≤ 1.11). Treatment of poly 3c with trifluoroacetic acid simultaneously removed the MEM and OOB groups, affording poly(o‐hydroxyamide) (poly 4 ) without scission of the amide linkages. Cyclodehydration of poly 4 proceeded at 350 °C to yield PBO (poly 5 ), which was insoluble in organic solvents and acids. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1730–1736     

Microwave‐assisted ring‐opening polymerization of ϵ‐caprolactone

Ring‐opening polymerization of ?‐caprolactone was carried out smoothly and effectively with constant microwave powers of 170, 340, 510, and 680 W, respectively, with a microwave oven at a frequency of 2.45 GHz. The temperature of the polymerization ranged from 80 to 210 °C. Poly(?‐caprolactone) (PCL) with a weight‐average molar mass (M_w) of 124,000 g/mol and yield of 90% was obtained at 680 W for 30 min using 0.1% (mol/mol) stannous octanoate as a catalyst. When the polymerization was catalyzed by 1% (w/w) zinc powder, the M_w of PCL was 92,300 g/mol after the reaction mixture was irradiated at 680 W for 270 min. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1749–1755, 2002     

Polymerization of higher linear α‐olefins with (CH3)2Si(2‐methylbenz[e]indenyl)2ZrCl2

Poly‐α‐olefins ranging from poly‐1‐pentene to poly‐1‐octadecene with narrow polydispersities were synthesized with (CH₃)₂Si(2‐methylbenz[e]indenyl)₂ZrCl₂ and methylaluminoxane at polymerization temperatures (T_p 's) ranging from −15 to 180 °C and were characterized by gel permeation chromatography, NMR spectroscopy, and differential scanning calorimetry. The molar masses of the homopolymers obtained with (CH₃)₂Si(2‐methylbenz[e]indenyl)₂ZrCl₂ were notably higher than those of poly‐α‐olefins synthesized with other zirconium‐based metallocenes under similar conditions. The temperature dependence of the molar mass distribution of the poly‐α‐olefins can be described by a common exponential decay function regardless of the investigated monomer. At T_p 's ranging from 20 to 100 °C, moderate isotacticity prevailed, but outside this temperature range, the polymers were less stereoregular. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2333–2339, 2000     

Radical polymerization of new functional monomer: Methacryloyl isocyanate containing 4‐chloro‐1‐phenol

New functional monomer methacryloyl isocyanate containing 4‐chloro‐1‐phenol (CPHMAI) was prepared on reaction of methacryloyl isocyanate (MAI) with 4‐chloro‐1‐phenol (CPH) at low temperature and was characterized with IR, ¹H, and ¹³C‐NMR spectra. Radical polymerization of CPHMAI was studied in terms of the rate of polymerization, solvent effect, copolymerization, and thermal properties. The rate of polymerization of CPHMAI has been found to be smaller than that of styrene under the same conditions. Polar solvents such as dimethylsulfoxide (DMSO) and N,N‐dimethyl formamide (DMF) were found to slow the polymerization. Copolymerization of CPHMAI (M₁) with styrene (M₂) in tetrahydrofuran (THF) was studied at 60°C. The monomer reactivity ratio was calculated to be r₁ = 0.49 and r₂ = 0.66 according to the method of Fineman—Ross. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 469–473, 2000     

Synthesis and characterization of L‐leucine containing chiral vinyl monomer and its polymer,poly(2‐(methacryloyloxyamino)‐4‐methyl pentanoic acid)

A chiral monomer containing L ‐leucine as a pendant group was synthesized from methacryloyl chloride and L ‐leucine in presence of sodium hydroxide at 4 °C. The monomer was polymerized by free radical polymerization in propan‐2‐ol at 60 °C using 2,2′‐azobis isobutyronitrile (AIBN) as an initiator under nitrogen atmosphere. The polymer, poly(2‐(Methacryloyloxyamino)‐4‐methyl pentanoic acid) is thus obtained. The molecular weight of the polymer was determined to be: M_w is 6.9 × 10³ and M_n is 5.6 × 10³. The optical rotation of both chiral monomer and its polymer varies with the solvent polarity. The amplification of optical rotation due to transformation of monomer to polymer is associated with the ordered conformation of chiral monomer unit in the polymeric chain due to some secondary interactions like H‐bonding. The synthesized monomer and polymer exhibit intense Cotton effect at 220 nm. The conformation of the chain segments is sensitive to external stimuli, particularly the pH of the medium. In alkaline medium, the ordered chain conformation is destroyed resulting disordered random coils. The ordered coiling conformation is more firmly present on addition of HCl. The polymer exhibits swelling‐deswelling characteristics with the change of pH of the medium, which is reversible. The Cotton effect decreases linearly with the increase of temperature which is reversible on cooling. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2228–2242, 2009     

Poly(ε‐caprolactone) by combined ring‐opening polymerization and azeotropic polycondensation—the role of cyclization and equilibration

Using three different catalysts, water‐initiated polymerizations of ε‐caprolactone were conducted in bulk with variation of the monomer/water ratio. The resulting CH₂OH and CO₂H‐ terminated polylactones were subjected in situ to azeotropic polycondensations. With Bi‐triflate and temperatures, the polycondensations were not much successful and involved side reactions. With ZnCl₂, and especially SnCl₂, considerably higher molar masses were achieved. The substitution of toluene for chlorobenzene for refluxing gave better results. The polycondensations broadened the molar mass distribution of the ROP‐based prepolymers, and polydispersities between 1.4–1.8 were obtained. The MALDI–TOF mass spectra revealed that the polycondensations significantly enhanced the fraction of rings due to efficient “end‐biting” reactions. By comparison with copolymerization experiments and Sn methoxide‐initiated polymerizations, it was demonstrated that equilibration reactions, such as the formation of rings by “back‐biting,” did not occur. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Chain‐growth condensation polymerization of 4‐aminobenzoic acid esters bearing tri(ethylene glycol) side chain with lithium amide base

Chain‐growth condensation polymerization of p‐aminobenzoic acid esters 1 bearing a tri(ethylene glycol) monomethyl ether side chain on the nitrogen atom was investigated by using lithium 1,1,1,3,3,3‐hexamethyldisilazide (LiHMDS) as a base. The methyl ester monomer 1a afforded polymer with low molecular weight and a broad molecular weight distribution, whereas the polymerization of the phenyl ester monomer 1b at ?20 °C yielded polymer with controlled molecular weight (M_n = 2800–13,400) and low polydispersity (M_w/M_n = 1.10–1.15). Block copolymerization of 1b and 4‐(octylamino)benzoic acid methyl ester ( 2 ) was further investigated. We found that block copolymer of poly 1b and poly 2 with defined molecular weight and low polydispersity was obtained when the polymerization of 1b was initiated with equimolar LiHMDS at ?20 °C and continued at ?50 °C, followed by addition of 2 and equimolar LiHMDS at ?10 °C. Spherical aggregates were formed when a solution of poly 1b in THF was dropped on a glass plate and dried at room temperature, although the block copolymer of poly 1b and poly 2 did not afford similar aggregates under the same conditions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1357–1363, 2010     

Synthesis and characterization of poly(3,3 bis(azidomethyl)oxetane‐co‐ε‐caprolactone)s

The quasi‐living cationic copolymerization of 3,3‐bis(chloromethyl)oxetane (BCMO) and ε‐caprolactone (ε‐CL), using boron trifluoride etherate as catalyst and 1,4‐butanediol as coinitiator, was investigated in methylene chloride at 0°C. The resulting hydroxyl‐ended copolymers exhibit a narrow molecular weight polydispersity and a functionality of about 2. The reactivity ratios of BCMO (0.26) and ε‐CL (0.47), and the T_g of the copolymers, indicate their statistical character. The synthesis of poly(3,3‐bis(azidomethyl)oxetane‐co‐ε‐caprolactone) from poly(BCMO‐co‐ε‐CL) via the substitution of the chlorine atoms by azide groups, using sodium azide in DMSO at 110°C, occurs without any degradation, but the copolymers decompose at about 240°C. All polymers were characterized by vapor pressure osmometry or steric exclusion chromatography, ¹H‐NMR and FTIR spectroscopies, and DSC. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1027–1039, 1999     

Controllable ring‐opening copolymerization of L‐lactide and (3S)‐benzyloxymethyl‐(6S)‐methyl‐morpholine‐2,5‐dione initiated by a biogenic compound creatinine acetate

Ring‐opening copolymerization (ROCP) of L ‐lactide (L ‐LA) and (3S)‐benzyloxymethyl‐(6S)‐methyl‐morpholine‐2,5‐dione [(3S, 6S)‐BMMD] initiated by creatinine acetate, a biogenic organic compound, was performed in the bulk at 130 °C. The copolymerization was well controlled as evidenced by that both the measured values of number‐average molecular weight (M_n,NMR(OH) and M_n,NMR(COOH)) and serine molar fraction (F_Bz.ser) of synthesized copolymers were close to the corresponding theoretical values; and that the higher isotacticity of synthesized copolymers (85–86%) and lower racemization degree of the ROCP. After removing O‐benzyls of the copolymers with Et₃SiH/Et₃N/CH₂Cl₂ under catalysis of PdCl₂, functional biodegradable copolymers of L ‐lactic acid (L ‐Lac) and L ‐Ser with designed molar fraction of serine (F_ser 1.35%, 3.57%, 5.41%), narrow molecular weight distribution (polydispersity index 1.10–1.36), and improved hydrophilicity (θ_stat 82.3–89.6°) were finally obtained. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Cationic polymerizations of 2‐alkyloxazolines catalyzed by bismuth salts

Acidic bismuth salts, such as BiCl₃, BiBr₃, BiJ₃, and Bi‐triflate catalyzed the ring‐opening polymerization of 2‐methoxazoline (MOZ) in bulk at 100 °C, whereas less acidic salts such as Bi₂O₃ or Bi(III)acetate did not. Bi‐triflate‐catalyzed polymerizations of 2‐ethyloxazoline (EtOZ) were performed with variation of the monomer–catalyst ratio (M/C). It was found that the molecular weights were independent of the M/C ratio. The formation of cationic chain ends and the absence of cycles was proven by reactions of virgin polymerization products with N,N‐dimethyl‐4‐aminopyridine or triphenylphosphine. The resulting polymers having modified cationic chain ends were characterized by ¹H NMR spectroscopy and MALDI‐TOF mass spectrometry. The polymerization mechanism including chain‐transfer reactions is discussed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4777–4784, 2008     

Synthesis and characterization of poly(L‐lactide)s and poly(D‐lactide)s of controlled molecular weight

High molecular weight poly(L ‐lactide)s (PLLAs) and poly(D ‐lactide)s (PDLAs) were synthesized in toluene at 70 °C by ring‐opening polymerization of optically pure L ‐lactide and D ‐lactide, using tin(II) 2‐ethylhexanoate (SnOct₂) and 2‐(2‐methoxyethoxy)ethanol as initiator and coinitiator, respectively. Under these conditions, polarimetry as well as ¹³C NMR spectroscopy indicated that the synthesized poly(lactide)s (PLAs) are more than 99% isotactic. The molecular weight was successfully controlled by adjusting the monomer‐to‐initiator molar ratio. Gel permeation chromatography and MALDI‐TOF mass spectrometry analyses showed that the polydispersity index of the PLAs is below 1.1. Moreover, MALDI‐TOF spectra showed two different chain distributions, one characterized by an even number of lactic acid repeat units and the other by an odd number of lactic acid repeat units. The second distribution, indicative of the presence of intermolecular transesterification reactions, appears at the very beginning of the polymerization and its intensity increases with the polymerization time. Finally, a reversible reaction kinetic model was used to determine the monomer equilibrium concentration ([M]_eq = 1.4 ± 0.5%) and the propagation rate constant (k_p = 14.4 ± 0.5 L mol^?1 h^?1) of the polymerization. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1944–1955, 2007     

Polar,functionalized diene‐based materials. V. Free‐radical polymerization of 2‐[(N‐benzyl‐n‐methylamino)methyl]‐1,3‐butadiene and copolymerization with styrene

2‐[(N‐Benzyl‐N‐methylamino)methyl]‐1,3‐butadiene (BMAMBD), the first asymmetric tertiary amino‐containing diene‐based monomer, was synthesized by sulfone chemistry and a nickel‐catalyzed Grignard coupling reaction in high purity and good yield. The bulk and solution free‐radical polymerizations of this monomer were studied. Traditional bulk free‐radical polymerization kinetics were observed, giving polymers with 〈M_n〉 values of 21 × 10³ to 48 × 10³ g/mol (where M_n is the number‐average molecular weight) and polydispersity indices near 1.5. In solution polymerization, polymers with higher molecular weights were obtained in cyclohexane than in tetrahydrofuran (THF) because of the higher chain transfer to the solvent. The chain‐transfer constants calculated for cyclohexane and THF were 1.97 × 10^?3 and 5.77 × 10^?3, respectively. To further tailor polymer properties, we also completed copolymerization studies with styrene. Kinetic studies showed that BMAMBD incorporated into the polymer chain at a faster rate than styrene. With the Mayo–Lewis equation, the monomer reactivity ratios of BMAMBD and styrene at 75 °C were determined to be 2.6 ± 0.3 and 0.28 ± 0.02, respectively. Altering the composition of BMAMBD in the copolymer from 17 to 93% caused the glass‐transition temperature of the resulting copolymer to decrease from 64 to ?7 °C. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3227–3238, 2001     

Synthesis of three‐armed poly(trans‐4‐hydroxy‐N‐benzyloxycarbonyl‐L‐proline)‐block‐poly(ε‐caprolactone) copolymers

A series of novel types of three‐armed poly(trans‐4‐hydroxy‐N‐benzyloxycarbonyl‐L ‐proline)‐block‐poly(ε‐caprolactone) (PHpr‐b‐PCL) copolymers were successfully synthesized via melt block copolymerization of trans‐4‐hydroxy‐N‐benzyloxycarbonyl‐L ‐proline (N‐CBz‐Hpr) and ε‐caprolactone (ε‐CL) with a trifunctional initiator trimethylolpropane (TMP) and stannous octoate (SnOct₂) as a catalyst. For the homopolycondensation of N‐CBz‐Hpr with TMP initiator and SnOct₂ catalyst, the number‐average molecular weight (M_n) of prepolymer increases from 530 to 3540 g mol^?1 with the molar ratio of monomer to initiator (3–30), and the molecular weight distribution (M_w/M_n) is between 1.25 to 1.32. These three‐armed prepolymer PHpr were subsequently block copolymerized with ε‐caprolactone (ε‐CL) in the presence of SnOct₂ as a catalyst. The M_n of the copolymer increased from 2240 to 18,840 g mol^?1 with the molar ratio (0–60) of ε‐CL to PHpr. These products were characterized by differential scanning calorimetry (DSC), ¹H NMR, and gel permeation chromatography. According to DSC, the glass‐transition temperature (T_g) of the three‐armed polymers depended on the molar ratio of monomer/initiator that were added. In vitro degradation of these copolymers was evaluated from weight‐loss measurements and the change of M_n and M_w/M_n. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1708–1717, 2005     

Anionic polymerization of N,N‐dialkyl‐2‐methylenebut‐3‐enamide: Effect of alkyl substituents on polymerization behavior

Anionic polymerizations of three 1,3‐butadiene derivatives containing different N,N‐dialkyl amide functions, N,N‐diisopropylamide (DiPA), piperidineamide (PiA), and cis‐2,6‐dimethylpiperidineamide (DMPA) were performed under various conditions, and their polymerization behavior was compared with that of N,N‐diethylamide analogue (DEA), which was previously reported. When polymerization of DiPA was performed at ?78 °C with potassium counter ion, only trace amounts of oligomers were formed, whereas polymers with a narrow molecular weight distribution were obtained in moderate yield when DiPA was polymerized at 0 °C in the presence of LiCl. Decrease in molecular weight and broadening of molecular weight distribution were observed when polymerization was performed at a higher temperature of 20 °C, presumably because of the effect of ceiling temperature. In the case of DMPA, no polymer was formed at 0 °C and polymers with relatively broad molecular weight distributions (M_w/M_n = 1.2) were obtained at 20 °C. The polymerization rate of PiA was much faster than that of the other monomers, and poly(PiA) was obtained in high yield even at ?78 °C in 24 h. The microstructure of the resulting polymers were exclusively 1,4‐ for poly(DMPA), whereas 20–30% of the 1,2‐structure was contained in poly(DiPA) and poly(PiA). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3714–3721, 2010     

Reactions of vinyl ethers with 2‐cyano‐2‐propyl and benzoyloxy radicals

tert‐Butyl, cyclohexyl, n‐propyl, and n‐dodecyl vinyl ethers have been used as comonomers with styrene and methyl methacrylate using ¹³C‐enriched samples of azobis(isobutyronitrile) and benzoyl peroxide as initiators at 60°C. Examination by ¹³C‐NMR spectroscopy of either (¹³CH₃)₂C(CN) or Ph¹³COO end‐groups in the products has shown that the vinyl ethers have low reactivities toward the 2‐cyano‐2‐propyl radical but high reactivities toward the benzoyloxy radical. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 771–777, 1999     

Polymerization of 1,3‐dienes with functional groups. II. Free‐radical polymerization of N‐(2‐methylene‐3‐butenoyl)piperidine

The free‐radical homopolymerization and copolymerization behavior of N‐(2‐methylene‐3‐butenoyl)piperidine was investigated. When the monomer was heated in bulk at 60 °C for 25 h without an initiator, about 30% of the monomer was consumed by the thermal polymerization and the Diels–Alder reaction. No such side reaction was observed when the polymerization was carried out in a benzene solution with 1 mol % 2,2′‐azobisisobutylonitrile (AIBN) as an initiator. The polymerization rate equation was found to be R_p ∝ [AIBN]^0.507[M]^1.04, and the overall activation energy of polymerization was calculated to be 89.5 kJ/mol. The microstructure of the resulting polymer was exclusively a 1,4‐structure that included both 1,4‐E and 1,4‐Z configurations. The copolymerizations of this monomer with styrene and/or chloroprene as comonomers were carried out in benzene solutions at 60 °C with AIBN as an initiator. In the copolymerization with styrene, the monomer reactivity ratios were r₁ = 6.10 and r₂ = 0.03, and the Q and e values were calculated to be 10.8 and 0.45, respectively. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1545–1552, 2003