Radical/Cation Transformation Polymerization and Its Application to the Preparation of Block Copolymers

✍ Scribed by Hai-Qing Guo; Atsushi Kajiwara; Yotaro Morishima; Mikiharu Kamachi

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 296 KB
• Volume: 8
• Category: Article
• ISSN: 1042-7147
• DOI: 10.1002/(sici)1099-1581(199704)8:4<196::aid-pat628>3.0.co;2-m

✦ Synopsis

Propagating radicals could be transformed into corresponding cations in the radical polymerization process of vinyl monomers in the presence of an electron acceptor. The electron transfer reaction from the propagating radicals to the acceptor was confirmed by an electron spin resonance study and by the model compound reaction. The radical/cation transformation polymerization was effectively applied to the preparation of a new type of block copolymer compound of radically polymerized segments and cationically polymerized segments by the one shot method. Thus, a block copolymer of p-methoxystyrene (MOS) and cyclohexene oxide (CHO) was prepared by the radical polymerization of MOS in the presence of Ph 2 I + PF Ϫ

6 and CHO. The formation of the block copolymer was confirmed by extraction separation, 1 H-NMR (nuclear magnetic resonance), thin layer chromatography and turbidimetric titration.