Termination Rate Constants Research Articles

Kinetic and ESR Studies of Ring-Opening Radical Polymerization of 1,1-Bis(ethoxycarbonyl)-2-vinylcyclopropane

Ring-opening radical polymerization of 1,1-bis(ethoxycarbonyl)-2-vinylcyclopropane (BEVCP) with dimethyl 2,2‘-azobisisobutyrate (MAIB) was investigated kinetically in benzene. The overall activation energy (Ea = 94 ± 4 kJ/mol) was calculated from the polymerization rate (Rp) obtained at 30−60 °C. Rp (40 °C) is given by Rp = k[MAIB]0.6±0.1[BEVCP]1.0±0.1, which is similar to that of conventional radical polymerizations involving bimolecular termination. The present polymerization system involves ESR-observable polymer radicals under the actual polymerization conditions. The total polymer radical concentration ([P•]) was determined at different temperatures by ESR. Using Rp, [P•], and the initiation rate obtained separately, the apparent rate constants of propagation (kp) and termination (kt) were estimated at different temperatures. The kp (71 L/mol·s, 60 °C) and kt (5.8 × l04 L/mol·s, 60 °C) values are much lower than those of typical vinyl monomers such as methyl methacrylate (MMA) and styrene. Owing to t...

EPR study of the radical polymerization of 3-[tris(trimethylsilyloxy)silyl]propyl methacrylate

The kinetics of the radical polymerization of 3-[tris(trimethylsilyloxy)silyl]propyl methacrylate was studied in benzene and dioxane/hexane solutions at different conditions of temperature, monomer and initiator concentrations by using ultraviolet and electron paramagnetic resonance spectroscopic techniques. The values of the ratios between the propagation rate constant and the square root of the termination rate constant (kp/kt1/2) were determined by UV spectroscopy by measuring the changes of absorbance with time at several wavelengths in the range 275–285nm, where appropriate changes in absorbance were observed. The values of kp/kt1/2, in the temperature interval 50–70°C, lie in the range 0.40–0.53l−1/2mol−1/2s−1/2. Measurements of the radical concentrations, the efficiency factor of the initiator and of the absolute rate constants kp and kt were carried out using electron paramagnetic resonance techniques. The values of kp are in the range 500–1000lmol−1s−1 in the temperature interval 50–70°C, in fair agreement with those extrapolated from results obtained by pulsed-laser/size-exclusion chromatography at lower temperatures.

Pyrolysis Kinetics for Long-Chain n-Alkylcyclohexanes

We report new experimental data and a general, mechanism-based structure−reactivity relationship for the pyrolysis of long-chain n-alkylcyclohexanes. The relationship has as its foundation the previously deduced free-radical reaction mechanism for alkylcyclohexane pyrolysis. The model is general because it incorporates the effect of the alkyl chain length on the global kinetics by accounting for the chain-length-dependent reaction path degeneracy of the initiation, β-scission, and hydrogen-abstraction steps. The global kinetics determined from the model for pyrolyses at 400 °C and an initial reactant concentration of 0.13 mol/L are in good accord with the experimentally determined rate constants for nine different n-alkylcyclohexanes with aliphatic substituents ranging from butyl (n-C4) to octadecyl (n-C18). A sensitivity analysis reveals that the rate constants for initiation, termination, and β-scission to form a primary radical had the greatest influence on the calculated pyrolysis rate. This work prov...

Kinetic study by differential scanning calorimetry of the bulk copolymerization of 2‐hydroxyethylmethacrylate with ethyleneglycoldimethacrylate

AbstractThis article presents a kinetic study of the copolymerization of 2‐hydroxyethylmethacrylate (HEMA) with ethyleneglycoldimethacrylate (EGDMA). First, the rate constant of decomposition, kd, of azobisisobutyronitrile (AIBN) used to initiate the copolymerization was investigated. Then, the reactivity ratios, r1 and r2, of the monomers (HEMA and EGDMA), and the termination rate constant, kt, were determined. Rate constants were obtained by differential scanning calorimetry (DSC) experiments. The decomposition rate constant of AIBN follows an Arrhenius law in the temperature range 320–400 K. Copolymerizations were carried out in the pans of the DSC apparatus at 353 K. The reactivity ratios, determined after analysis of the mixture composition by gas chromatography, exploitation of the data using the Meyer and Lowry equation, and a numerical method, were found equal to r1 = 0.811 and r2 = 6.548. Also from the reaction rate obtained by DSC, the dependence of the termination rate constant with conversion and temperature has been established. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1220–1228, 2001

Radical and cationic polymerizations of 3‐ethyl‐3‐methacryloyloxymethyloxetane

Abstract3‐Ethyl‐3‐methacryloyloxymethyloxetane (EMO) was easily polymerized by dimethyl 2,2′‐azobisisobutyrate (MAIB) as the radical initiator through the opening of the vinyl group. The initial polymerization rate (Rp) at 50 °C in benzene was given by Rp = k[MAIB]0.55 [EMO]1.2. The overall activation energy of the polymerization was estimated to be 87 kJ/mol. The number‐average molecular weight (M̄n) of the resulting poly(EMO)s was in the range of 1–3.3 × 105. The polymerization system was found to involve electron spin resonance (ESR) observable propagating poly(EMO) radicals under practical polymerization conditions. ESR‐determined rate constants of propagation (kp) and termination (kt) at 60 °C are 120 and 2.41 × 105 L/mol s, respectively—much lower than those of the usual methacrylate esters such as methyl methacrylate and glycidyl methacrylate. The radical copolymerization of EMO (M1) with styrene (M2) at 60 °C gave the following copolymerization parameters: r1 = 0.53, r2 = 0.43, Q1 = 0.87, and e1 = +0.42. EMO was also observed to be polymerized by BF3OEt2 as the cationic initiator through the opening of the oxetane ring. The M̄n of the resulting polymer was in the range of 650–3100. The cationic polymerization of radically formed poly(EMO) provided a crosslinked polymer showing distinguishably different thermal behaviors from those of the radical and cationic poly(EMO)s. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1269–1279, 2001

KINETICS OF THE NON-STATIONARY PHOTOPOLYMERIZATION OF SOME DIACRYLATE MONOMERS

The kinetics of non-stationary photopolymerization (post- polymeryzation) of some diacrylate monomers at the wide range of initial conversions was investigated. All kinetic curves has two regions: quick and short, and slow and long. Experimental data were compared with the kinetic model of the photoinitial three-dimensional photopolymerization. It was determined that the kinetic model allows us to describe the post-polymerization process in the whole range of conversions. The rate constants of the linear termination of primary and secondary chains in the interphase layer were estimated. The increasing rate constants in the interphase are similar for investigated diacrylates and do not depend on the glycol chain lengths.

The Persistent Radical Effect in Nitroxide Mediated Polymerization: Experimental Validity

The free-radical polymerization of styrene has been studied at 123°C in the presence of a betaphosphonylated alkoxyanine (diethyl[(1,1-dimethylethyl)(1-phenylethoxy)amino]-2,2-dimenthylpropyl phosphonate) (stryl-DEPN). The persistent radical effect is undoubtedly observed experimentally until the effect of viscosity on the rate constant of termination is no longer negligible. The kinetic laws of the persistent radical effect allow us to calculate the pseudo equilibrium constant of dissociation/combination between dormant and active species k polystyryl-DEPN = 6.1 x 10 -9 mol . L ―1 at 123°C. We have verified the reliability of this constant by computer simulation in comparision with the experimental data.

A general solution of the closed-loop kinetic scheme for the thermal oxidation of polypropylene

A general solution of the closed-loop kinetic scheme for the thermal oxidation of hydrocarbon polymers is presented in which no assumptions are made concerning the concentration of oxygen, the kinetic chain length, the ratio of termination rate constants or the existence of a steady-state for the concentration of radicals. The proposed model is used to simulate the thermal oxidation of unstabilized polypropylene films under ambient air at 80–150 °C, with reaction and diffusion parameters that result in realistic estimates of induction times, hydroperoxide concentrations and oxygen uptakes. Simulation results indicate that the oxidation of films 10–100 μm thick is likely to become oxygen-diffusion-limited before the end of the induction time for oxygen absorption, with heterogeneous degradation predominating as the process approaches stationary conditions. The model is used, among others, to identify operating conditions under which the oxidation process may be considered free of oxygen mass transfer limitations.

Kinetic and ESR studies on the radical polymerization of α‐n‐(α′‐methylbenzyl) β‐ethyl itaconamates derived from racemic and (s)‐α‐methylbenzylamines

The polymerization of α-N-(α′-methylbenzyl) β-ethyl itaconamate derived from racemic α-methylbenzylamine (RS-MBEI) by initiation with dimethyl 2,2′-azobisisobutyrate (MAIB) was studied in methanol kinetically and with ESR spectroscopy. The overall activation energy of polymerization was calculated to be 47 kJ/mol, a very low value. The polymerization rate (Rp ) at 60 °C was expressed by Rp = k[MAIB]0.5±0.05[RS-MBEI]2.9±0.1. The rate constants of propagation (kp ) and termination (kt ) were determined by ESR. kp was very low, ranging from 0.3 to 0.8 L/mol s, and increased with the monomer concentration, whereas kt (4–17 × l04 L/mol s) decreased with the monomer concentration. Such behaviors of kp and kt were responsible for the high dependence of Rp on the monomer concentration. Rp depended considerably on the solvent used. S-MBEI, derived from (S)-α-methylbenzylamine, showed somewhat lower homopolymerizability than RS-MBEI. The kp value of RS-MBEI at 60 °C in benzene was 1.5 times that of S-MBEI. This was explicable in terms of the different molecular associations of RS-MBEI and S-MBEI, as analyzed by 1H NMR. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4137–4146, 2000

The effect of TMEDA on the kinetics of the anionic polymerization of methyl methacrylate in tetrahydrofuran using lithium as counterion

The kinetics of the anionic polymerization of methyl methacrylate in presence of N,N,N', -tetramethylethylenediamine (TMEDA) in THF are investigated using 1,1-diphenyl-hexyllithium as initiator in a temperature range between -20°C and 0°C in a flow-tube reactor. The rate constants of propagation determined in the presence of TMEDA are compared to those obtained in the absence of a chelating agent. For propagation, the reaction order with respect to active centers is found to be 0.5 in both cases which indicates that the chelation of the lithium cation does not effectively perturb the aggregation of the enolate ion pair. Both the rate constants of propagation via non-aggregated ion pairs, k ± , and the equilibrium constants of aggregation, K A , are not significantly affected by TMEDA. The rate constants of termination in absence and presence of TMEDA are also comparable. Thus, it is concluded that TMEDA is not a better ligand for lithium ester enolates than THF. Even the addition of a cyclic tertiary polyamine (crown amine) such as 1,4,8,11-tetramethyltetraazacyclotetradecane, does not lead to a significant change in the propagation rate constant, however, no termination is observed at -20°C. Extrapolation of the observed rate constants at two temperatures gives estimates for the equilibrium constants of aggregation, K A , and the corresponding enthalpy and entropy. It is shown, that aggregation of PMMA-Li in THF is an endothermic, entropy-driven process (ΔH A ; ΔS A > 0), similar to the dimer-tetramer equilibrium of model ester enolates.

Chemilumunescence of Isotactic Polypropylene Induced by UV Irradiation

The kinetics of the weak Chemilumunescence (CL) and peroxyl radical decay after UV irradiation of isotactic polypropylene (PP) have been studied. The correlation has been found between CL and the reaction of chain termination under the PP post-oxidation at room temperature in air. Kinetics of CL decay, its compliance with kinetics of peroxyl radical decay, relative quantum yield of CL per one act of radical termination and effects of the plasticizer, accelerating both radical termination and CL decay, have been determined. Kinetic features of CL decay indicates the distributions of peroxyl radicals on both rate constants of termination and quantum yields of CL in the acts of the disproportionation of two peroxyl radicals. In terms of these distributions it is possible to describe quantitatively observed kinetics of CL decay under the post oxidation of PP after the UV irradiation in air.

Cationic macromolecular engineering via furan derivatives

General methodologies for the synthesis of linear and star-block copolymers and functional polymers using furan derivatives are reviewed, based on a study of addition reactions of 2-substituted furans to living polyisobutylene (PIB+). Rapid and quantitative mono-addition of 2-alkyl (and aryl)furans (2-R-Fu), a new class of non-(homo)polymerizable monomers, to PIB+ has been observed in conjunction with TiCl4 as Lewis acid in hexane/CH2Cl2 or CH3Cl 60/40 (v/v) at −80 °C and with BCl3 in CH3Cl at −40 °C, in the presence of proton trap. The resulting stable allylic cation (PIB-Fu+-R) was found to be an efficient initiating species for the polymerization of methyl vinyl ether (MeVE). Using 2,5-bis[1-furanyl)-1-methylethyl]-furan, coupling of living PIB was found to be rapid and quantitative in hexanes(Hex)/CH3Cl 60/40 or 40/60 (v/v) solvent mixtures at −80 °C in conjunction with TiCl4, as well as in CH3Cl at −40 °C with BCl3 as Lewis acid. The kinetics of addition of 2-R-Fu to PIB+ was investigated by UV-vis spectroscopy. Based on these results and those obtained with substituted 1,1-diarylethylenes earlier, the absolute rate constants of ionization (ki), reversible termination (k−i) and propagation (kp) in the polymerization of IB have been determined. By a similar approach the corresponding rate constants have also been determined for the polymerization of styrene.

Kinetic Study on Free Radical Polymerization of 2-Acetamidoacrylic Acid and Formation of Hydrogel

Radical polymerization of captodative (cd) substituted 2-acetamidoacrylic acid (1) was studied kinetically at 40°C. The rate constants of propagation (kp) and termination (kt) of 1 were estimated by a rotating sector and an inhibitor method using 1,3,5-triphenylverdazyl. Termination was depressed and kp/kt became high, which was responsible for the high radical polymerization reactivity of 1 in spite of the cd olefin. The hydrogel consisting of poly(acetyl dehydroalanine) network was synthesized by the copolymerization of 1 and bifunctional cross-linker with the structure analogous to 1. The swelling ratio of the gel was dependent on the cross-linker concentration and reached a maximum of 1334 at 2% cross-linker concentration in the feed. The gel showed stimuli-responce to pH and electric field, i.e., the gel volume increased to twice as much when transferred from an acidic solution into an alkaline solution and the gel bent toward an anode side within a few minutes when the electric field was applied. Biodegradability of the polymers was examined using α-chymotrypsin.

Radical polymerization of phenyl acrylate as studied by ESR spectroscopy: concurrence of propagating and mid-chain radicals

The electron spin resonance (ESR) spectrum of the propagating radical of phenyl acrylate (PhA) was successfully recorded in benzene as a non-polar solvent. The hyperfine coupling constants for the α and β-protons were evaluated on the basis of the spectra of the propagating radicals of PhA and phenyl acrylate-α-d. The simulated spectrum satisfactorily fits those observed during polymerization, and the spectrum of the poly(PhA) radical obtained at low conversion (<15%) was assigned to the propagating radical. The spectra observed at higher conversions (>15%) indicated the presence of two types of radical species, a propagating radical and a mid-chain radical produced by abstraction of the α-hydrogen of the monomeric unit. The content of branching in the polymers as a result of the formation of a mid-chain radical was found to be 1–3% by 13C NMR spectroscopy. The absolute rate constants for propagation (kp) and termination (kt) of PhA at low conversions were determined based on the quantification of the propagating radical by ESR spectroscopy at 60°C: kp = 3 580 dm3·mol–1·s–1 and kt = 6,8×106 dm3·mol–1·s–1. However, these seemed to be apparent values because the propagating radical is expected to be converted to the mid-chain radical by intra- and intermolecular hydrogen abstraction before the loss of its activity by bimolecular termination. Conversion from the propagating radical to the mid-chain radical followed by reinitiation was estimated to occur more than twenty times during the lifetime of each polymer chain.

Radical polymerization of phenyl acrylate as studied by ESR spectroscopy: concurrence of propagating and mid-chain radicals

The electron spin resonance (ESR) spectrum of the propagating radical of phenyl acrylate (PhA) was successfully recorded in benzene as a non-polar solvent. The hyperfine coupling constants for the α and β-protons were evaluated on the basis of the spectra of the propagating radicals of PhA and phenyl acrylate-α-d. The simulated spectrum satisfactorily fits those observed during polymerization, and the spectrum of the poly(PhA) radical obtained at low conversion (<15%) was assigned to the propagating radical. The spectra observed at higher conversions (>15%) indicated the presence of two types of radical species, a propagating radical and a mid-chain radical produced by abstraction of the α-hydrogen of the monomeric unit. The content of branching in the polymers as a result of the formation of a mid-chain radical was found to be 1–3% by 13C NMR spectroscopy. The absolute rate constants for propagation (kp) and termination (kt) of PhA at low conversions were determined based on the quantification of the propagating radical by ESR spectroscopy at 60°C: kp = 3 580 dm3·mol–1·s–1 and kt = 6,8×106 dm3·mol–1·s–1. However, these seemed to be apparent values because the propagating radical is expected to be converted to the mid-chain radical by intra- and intermolecular hydrogen abstraction before the loss of its activity by bimolecular termination. Conversion from the propagating radical to the mid-chain radical followed by reinitiation was estimated to occur more than twenty times during the lifetime of each polymer chain.

On the (im)possibility of evaluating correct individual rate constants of chain propagationkp and chain terminationkt by combiningkp2/kt andkp/kt data for chain-length dependent termination

On the basis of simulated data two ways of evaluating individual rate constants by combining kp2/kt and kp /kt (kp , kt = rate constants of chain propagation and termination, respectively) were checked considering the chain-length dependence of kt. The first way tried to make use of the fact that pseudostationary polymerization yields data for kp2/kt as well as for kp /kt referring to the very same experiment, in the second way kp2/kt (from steady state experiments) and kp/kt data referring to the same mean length of the terminating radical chains were compared. In the first case no meaningful data at all could be obtained because different averages of kt are operative in the expressions for kp /kt and kp2/kt. In spite of the comparatively small difference between these two averages (≈15% only) this makes the method collapse. The second way, which can be regarded as an intelligent modification of the “classical” method of determining individual rate constants, at least succeeded in reproducing the correct order of magnitude of the individual rate constants. However, although stationary and pseudostationary experiments independently could be shown to return the same kt for the same average chain-length of terminating radicals within extremely narrow limits no reasonable chain-length dependence of kt could be derived in this way. The reason is an extreme sensitivity of the pair of equations for kp/kt and kp2/kt towards small errors and inconsistencies which renders the method unsuccessful even for the high quality simulation data and most probably makes it even collapse for real data. This casts a characteristic light on the unsatisfactory situation with respect to individual rate constants determined in the classical way, regardless of a chain-length dependence of termination. As a consequence, all efforts of establishing the chain-length dependence of kt are recommended to avoid this way and should rather resort to methods based on inserting a directly determined kp into the equations characteristic of kp2/kt or kp/kt, properly considering the chain-length dependent character of kt.

Kinetic study on the radical polymerization of 2-methacryloyloxyethyl phosphorylcholine

Polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) was kinetically investigated in ethanol using dimethyl 2,2′-azobisisobutyrate (MAIB) as initiator. The overall activation energy of the homogeneous polymerization was calculated to be 71 kJ/mol. The polymerization rate (Rp) was expressed by Rp = k[MAIB]0.54±0.05 [MPC]1.8±0.1. The higher dependence of Rp on the monomer concentration comes from acceleration of propagation due to monomer aggregation and also from retardation of termination due to viscosity effect of the MPC monomer. Rate constants of propagation (kp) and termination (kt) of MPC were estimated by means of ESR to be kp = 180 L/mol · s and kt = 2.8 × 104 L/mol · s at 60 °C, respectively. Because of much slower termination, Rp of MPC in ethanol was found at 60 °C to be 8 times that of methyl methacrylate (MMA) in benzene, though the different solvents were used for MPC and MMA. Polymerization of MPC with MAIB in ethanol was accelerated by the presence of water and retarded by the presence of benzene or acetonitrile. Poly(MPC) showed a peculiar solubility behavior; although poly(MPC) was highly soluble in ethanol and in water, it was insoluble in aqueous ethanol of water content of 7.4–39.8 vol %. The radical copolymerization of MPC (M1) and styrene (St) (M2) in ethanol at 50 °C gave the following copolymerization parameters similar to those of the copolymerization of MMA and St; r1 = 0.39, r2 = 0.46, Q1 = 0.76, and e1 = +0.51. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 509–515, 2000

Influence of the stereochemical configuration on the radical polymerization of methacrylic monomers:cis- andtrans-(2-cyclohexyl-1,3-dioxan-5-yl) methacrylate

The synthesis of two new isomeric monomers, cis-(2-cyclohexyl-1,3-dioxan-5-yl) methacrylate (CCDM) and trans-(2-cyclohexyl-1,3-dioxan-5-yl) methacrylate (TCDM), starting from the reaction of glycerol and cyclohexanecarbaldehyde, is reported. The process involved the preparation of different alcohol acetals and esterification with methacryloyl chloride of the corresponding cis and trans 5-hydroxy compounds of 2-cyclohexyl-1,3-dioxane. The radical polymerization reactions of both monomers, under the same conditions of temperature, solvent, monomer, and initiator concentrations, were studied to investigate the influence of the monomer configuration on the values of the propagation and termination rate constants (kp and kt ).The values of the ratio kp /kt 1/2 were determined by UV spectroscopy by the measurement of the changes of absorbance with time at several wavelengths in the range 275–285 nm, where an appropriate change in absorbance was observed. Reliable values of the kinetics constants were determined by UV spectroscopy, showing a very good reproducibility of the kinetic experiments. The values of kp /kt 1/2, in the temperature interval 45–65 °C, lay in the range 0.40–0.50 L1/2/mol1/2s1/2 and 0.20–0.30 L1/2/mol1/2s1/2 for CCDM and TCDM, respectively. Measurements of both the radical concentrations and the absolute rate constants kp and kt were also carried out with electron paramagnetic resonance techniques. The values of kp at 60 °C were nearly identical for both the trans and cis monomers, but the termination rate constant of the trans monomer was about three times that of the cis monomer at the same temperature. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3883–3891, 2000

Kinetic and ESR studies on the radical polymerization of ?-n-(??-methylbenzyl) ?-ethyl itaconamates derived from racemic and (s)-?-methylbenzylamines

The polymerization of α-N-(α′-methylbenzyl) β-ethyl itaconamate derived from racemic α-methylbenzylamine (RS-MBEI) by initiation with dimethyl 2,2′-azobisisobutyrate (MAIB) was studied in methanol kinetically and with ESR spectroscopy. The overall activation energy of polymerization was calculated to be 47 kJ/mol, a very low value. The polymerization rate (Rp ) at 60 °C was expressed by Rp = k[MAIB]0.5±0.05[RS-MBEI]2.9±0.1. The rate constants of propagation (kp ) and termination (kt ) were determined by ESR. kp was very low, ranging from 0.3 to 0.8 L/mol s, and increased with the monomer concentration, whereas kt (4–17 × l04 L/mol s) decreased with the monomer concentration. Such behaviors of kp and kt were responsible for the high dependence of Rp on the monomer concentration. Rp depended considerably on the solvent used. S-MBEI, derived from (S)-α-methylbenzylamine, showed somewhat lower homopolymerizability than RS-MBEI. The kp value of RS-MBEI at 60 °C in benzene was 1.5 times that of S-MBEI. This was explicable in terms of the different molecular associations of RS-MBEI and S-MBEI, as analyzed by 1H NMR. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4137–4146, 2000

Kinetic and ESR studies on radical polymerization behavior ofN-(2-phenylethoxycarbonyl)methacrylamide

Polymerization of N-(2-phenylethoxycarbonyl)methacrylamide (PECMA) with dimethyl 2,2′-azobisisobutyrate (MAIB) was investigated in tetrahydrofuran (THF) kinetically and by means of electron spin resonance (ESR). The overall activation energy of the polymerization was calculated to be 58 kJ/mol. The initial polymerization rate (Rp) is expressed by Rp = k[MAIB]0.3[PECMA]2.3 at 60 °C. Such unusual kinetics may be ascribable to primary radical termination and to acceleration of propagation due to monomer association. Propagating poly(PECMA) radical was observed as a 13-line spectrum by ESR under practical polymerization conditions. ESR-determined rate constants of propagation (kp, 4.7–10.5 L/mol s) and termination (kt, 4.6 × 104 L/ml s) at 60 °C are much lower than those of methacrylamide and methacrylate esters. The Arrhenius plots of kp and kt gave activation energies of propagation (24 kJ/mol) and termination (25 kJ/mol). The copolymerizations of PECMA with styrene (St) and acrylonitrile were examined at 60 °C in THF. Copolymerization parameters obtained for the PECMA (M1) − St(M2) system are as follows: r1 = 0.58, r2 = 0.60, Q1 = 0.73, and e1 = +0.22. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4264–4271, 2000