Premium
Control of M n , M w / M n , end‐groups, and kinetics in living polymerization of cyclic esters
Author(s) -
Biela Tadeusz,
Duda Andrzej,
Penczek Stanislaw
Publication year - 2002
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/1521-3900(200207)183:1<1::aid-masy1>3.0.co;2-q
Subject(s) - molar mass , polymerization , kinetics , chemistry , polymer chemistry , molar mass distribution , metal , polyester , molar concentration , chain transfer , molar ratio , living polymerization , organic chemistry , polymer , radical polymerization , catalysis , physics , quantum mechanics
Factors affecting molar mass, molar mass distribution, end‐groups, and kinetics control in polymerization of ϵ‐caprolactone (CL) and L,L‐dilactide (LA) initiated by covalent alkylmetal alkoxides, metal alkoxides, and metal carboxylates are discussed. First, an importance of the reliable molar mass measurements of the resulting polyesters is stressed. Then, it is shown that R 2 AlOR', Al(OR) 3 , Sn(OR) 2 , and Sn[(O)OCR')] 2 /ROH initiators provide living polymerization of cyclic esters, in spite of the extensive aggregation phenomena. In LA polymerization Sn(II)‐alkoxides appeared to be particularly effective, allowing M n control in the range from 10 2 up to 10 6 . Conditions enabling side chain transfer reactions to be eliminated are also discussed.