Cationic polymerization of 1,3-dioxepane in the presence of 2,2-bis(hydroxymethyl)butanol

✍ Scribed by Cai-Yuan Pan; Ye Liu; Wei Liu

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 140 KB
• Volume: 36
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19981130)36:16<2899::aid-pola8>3.0.co;2-j

✦ Synopsis

Cationic polymerization of 1,3-dioxepane (DOP) initiated by triflic acid was carried out in the presence of 2,2-bis(hydroxymethyl)butanol (BHMB). The structure and molecular weight of the products were characterized by GPC and NMR spectra. The results showed that molecular weight of the polyacetal obtained could be controlled by the initial mole ratio of DOP/BHMB. GPC showed that as the mole ratio of BHMB/ DOP increased, the content of cyclic oligomers also increased. Proton, 13 C and 2D HMQC-fg NMR demonstrated that no hydroxymethyl group of BHMB appeared as an end group. It was also illustrated by proton NMR that some BHMB units existed in cyclic oligomers. The mechanism of formation of cyclic oligomers was discussed.