Cationic ring-opening copolymerization of seven-membered cyclic sulfite and oxetane in one-shot feeding

✍ Scribed by Natsuhiro Azuma; Fumio Sanda; Toshikazu Takata; Takeshi Endo

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 153 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19970430)35:6<1007::aid-pola3>3.0.co;2-1

✦ Synopsis

Cationic copolymerization of seven-membered cyclic sulfite, 1,3,2-dioxathiepane-2-oxide ( 1) and oxetane ( 2) in one-shot feeding was carried out to obtain the corresponding copolymer. When a mixture of equimolar amount of 1 and 2 reacted at 0ЊC in the presence of methyl trifluoromethanesulfonate (T fOMe) as a cationic initiator, T fOMe and 2 were completely consumed without the consumption of 1. After rising the polymerization temperature up to 25ЊC, 1 started to be consumed to obtain the corresponding copolymer of 1 and 2. The obtained copolymer showed a unimodal GPC curve, and it afforded a polyether showing a unimodal GPC after alkaline hydrolysis. These results strongly suggested the occurrence of the block copolymerization in one-shot feeding. From the molecular orbital examination, the formation of block copolymerization in one-shot feeding was discussed to be caused by the much larger polymerizability of 2 than that of 1.