## Abstract 1,1,2,2‐Tetraphenyl‐1,2‐diphenoxyethane (TPPA) initiates at 70°C the polymerization of methyl methacrylate. In the first period oligomers of the type **1** with two phenoxydiphenylmethyl end groups (__P__~n~ ≈ 1 – 20) magnified image are formed by primary radical termination. These tele
Polymerisationsauslösung mit substituierten ethanen, 4. Kinetik der polymerisation von methylmethacrylat mit 1,1,2,2-tetraphenyl-1,2-diphenoxyethan
✍ Scribed by Błedzki, Andrzej ;Balard, Henri ;Braun, Dietrich
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1981
- Weight
- 492 KB
- Volume
- 182
- Category
- Article
- ISSN
- 0025-116X
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✦ Synopsis
Abstract
The polymerisation of methyl methacrylate (MMA) by 1,1,2,2‐tetraphenyl‐1,2‐diphenoxyethane is characterised by three steps: during the initial period oligomers from MMA and initiator radicals are formed by primary radical termination. These oligomers produce free macroradicals and initiator radicals by cleavage at the bonds between the last monomer unit and the end group from the initiator. After consumption of the initiator radicals with increasing conversion the normal propagation and termination processes occur. The kinetics derived from this reaction scheme is in good agreement with the experimental results.
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