ISSN:
0887-624X
Keywords:
cationic ring-opening polymerization
;
poly(1,3-dioxepane) triol
;
2,2-bis(hydroxymethyl)butanol
;
transacetalization
;
activated monomer mechanism
;
activated chain mechanism
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
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, 13C 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. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2899-2903, 1998
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
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