High molecular weight poly(alpha-methylstyrene) formed by free radical polymerization in emulsions

Citation
Sc. Pilcher et Wt. Ford, High molecular weight poly(alpha-methylstyrene) formed by free radical polymerization in emulsions, J POL SC PC, 39(4), 2001, pp. 525-529
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
ISSN journal
0887-624X → ACNP
Volume
39
Issue
4
Year of publication
2001
Pages
525 - 529
Database
ISI
SICI code
0887-624X(20010215)39:4<525:HMWPFB>2.0.ZU;2-E
Abstract
Free radical polymerizations of ol-methylstyrene (AMS) were performed in di spersions of oil in water using a mixture of nonionic nonylphenoxy poly(eth ylene glycol) surfactants and initiated with ascorbic acid/hydrogen peroxid e at temperatures ranging from 3 to 45 degreesC. A bimodal distribution of high (similar to 60,000 g/mol) and low molecular weight components (similar to 8000 g/mol) was analyzed by size-exclusion chromatography (SEC). The re lative amount of the low molecular weight fraction increased with increasin g the polymerization temperature. The polymer yields decreased from 52% at 3 degreesC to 3% at 45 degreesC. The syndiotactic content of PAMS decreased from 70% rr at 3 degreesC to 58% rr at 45 degreesC. (C) 2001 John Wiley & Sons, Inc.