Studies in chain-transfer. Part 2.—Catalyzed polymerization of methyl methacrylate

Abstract

The chain-transfer constants of methyl methacrylate with fourteen solvents, using 2 : 2'-azobisisobutyronitrile as initiator has been determined at 60" and 80". The values of chain-transfer as determined at 60" are of the same order as with styrene, showing that the two monomers behave similarly in abstracting an cc-hydrogen atom from a solvent. The values of the absolute chain-transfer rates at 60" have been calculated and are found to be approximately half as compared with those of styrene. The energies of activation (Et,, s -E') and frequency factors [In ( A t , s/AP)] for various solvents have also been calculated.The chain-transfer reaction of methyl methacrylate at 80" C with a variety of solvents in the absence of any catalyst has been studied by Basu, Sen and Palit.1 These workers 2 have also made a study of the benzoyl-peroxide-catalyzed polymerization of the same monomer in toluene. In the present paper we report our * The previous publication, " Chain-transfer in the phenylazotriphenylmethane catalyzed polymerization of styrene in toluene " (Chadha and Misra, Makromol. Chem., 1954, 14, 97) is regaided as part 1 of this series.

Polymerization of mono‐, Di‐, and trichloroethyl methacrylates: A study in chain transfer

“…Measurements on the chloromethane set of compounds enable a comparison of C T magnitudes with those of the ClnEtOAc model compounds (Chart ). The CCl 4 > CHCl 3 > CH 2 Cl 2 order of chain transfer activity is in good agreement with previous reports that have studied this compound set with the MMA monomer, and the same ranking of activity is generally observed with other monomers . With respect to degree of chlorine substitution, the trend of this chloromethane compound set is opposite to that for the ClnEtOAc compound set and to that of the crosslinking activity observed for the PClnEMA polymerizations.…”

Use of Deep Eutectic Solvents in Polymer Chemistry–A Review

“…As a result, a polymer with a lower molecular weight is produced. Among classic organic solvents with high transfer effect, tetrahydrofuran, isopropanol, diisopropyl ether, chloroform and alkylated benzenes [54] can be mentioned. When polymerization occurs in a solvent with a low chain transfer rate (e.g., tert -butanol, water, benzene), a polymer with a high molecular weight is formed.…”

Studies on the Radical Polymerization of Methyl Methacrylate in Bulk and in Benzene Using Totally Deuterated Monomer Technique

“…2). The chain transfer constant to the solvent is reported to be 0.4 x 10-5 in the polymerization of MMA in benzene at 60°C, 32 and the degree of polymerization of the PMMA-d 8 to be less than 4 x 10 2 • The effect of the transfer reaction to benzene can thus be ignored. Then, the number of initiator fragments obtained here, 1.135 , is directly related to the relative importance of the disproportionation and combination reactions and indicates that 86.5% of Polymerization of MMA-d 8 was carried out in benzene at 60°C with BPO at the initial monomer concentration of 0.91 moll-1 .…”