ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The anionic ring-opening polymerization of mixtures of 2,2-dimethyltrimethylene carbonate (5,5-dimethyl-1,3-dioxan-2-one) (1) and pivalolactone (2,2-dimethyl-3-propanolide) (3) in toluene as a solvent and with potassium dihydronaphthylide as initiator, results in formation of block copolymers with yields of ca. 90%. In tetrahydrofuran as a solvent the polymer yields are ca. 65% only. In toluene, 1 polymerizes first and subsequently 3 resulting in a blocky structure of the copolymer. According to a mechanistic study, the active species is first a 1-alcoholate, later a 3-alcoholate and finally a 3-carboxylate. The copolymers are soluble in deuterochloroform up to a mole fraction of pivalolactone of ca. 0,40. By means of 13C NMR spectroscopy the blocky structure of the copolymers prepared in toluene was confirmed. In tetrahydrofuran as a solvent 1-3 and 3-1-diads are formed to a significant extent. The copolymers were characterized by thermoanalytical and thermomechanical measurements.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1990.021910901
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