Chain transfer by addition-substitution mechanism, 4. Alkyl permethacrylates — a new class of polymerization regulators
✍ Scribed by Philippe Chaumont; Daniel Colombani
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 432 KB
- Volume
- 196
- Category
- Article
- ISSN
- 1022-1352
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
tert‐Butyl permethacrylate (__t__BPM)Systematic names; t BPM: tert‐butyl peroxymethacrylate, CPM: α,α‐dimethylbenzyl peroxymethacrylate.
and cumyl permethacrylate (CPM)^b^ act as chain transfer agents in the free radical polymerization of methyl methacrylate and styrene at 50°C. Thermal degradation of the peresters occurs as a side‐reaction during the polymerization process. A modified Mayo equation (including the first‐order decomposition of the chain transfer agents) is proposed to calculate the chain transfer constants. The thermolysis activation energy of CPM (E~a,th~ = 121 ± 5kJ/mol) was estimated from the Arrhenius plot of the homolytic decomposition rate constants, K~th'~ at various temperatures.