Degree of Polymerization and Chain Transfer in Methyl Methacrylate
Abstract
The chain-transfer constants of twenty-six solvents in the polymerization of methyl methacrylate have been calculated, using Mayo's equation for chain-transfer reaction, from the measured values of degree of polymerization of the product formed in these solvents at different concentrations at 80 degrees C. The increase in transfer constants in hydrocarbons, alcohols, ketones, acids and ester may be effectively accounted for by the the increased polarization of the C\chembond{1,0} H bond at the α -position, by adjacent electron-attracting groups. In the case of chloro-compounds the activity has been found to depend not on the number of halogen atoms in the molecule as was suggested by Mayo but on the extent of C\chembond{1,0} Cl bond forces. Further, it is shown that simple chain transfer reactions with solvents cannot fully account for all the observed discrepancies in the kinetic measurements in solution.
- Publication:
-
Proceedings of the Royal Society of London Series A
- Pub Date:
- August 1950
- DOI:
- 10.1098/rspa.1950.0114
- Bibcode:
- 1950RSPSA.202..485B