Carsten Bolln, H. Frey, R. Mülhaupt
Apr 22, 1996
Citations
0
Influential Citations
10
Citations
Journal
Macromolecules
Abstract
Synthesis of the asymmetrically substituted 2-methylene-7-phenyl-1,4,6,9-tetraoxaspiro[4.4]nonane monomer in four steps and its polymerization are described. The spiromonomer is liquid at room temperature. Photoinitiated cationic polymerization of 2-methylene-7-phenyl-1,4,6,9-tetraoxaspiro[4.4]nonane at ambient temperature in bulk was investigated, using a cationic photoinitiator system based on (η5-2,4-cyclopentadiene-1-yl)[1,2,3,4,5,6-η](1-(methylethyl)benzene)iron(I) hexafluorophosphate (Irgacure 261). Upon irradiation, within 10 min quantitative double ring-opening polymerization to a structurally well-defined poly(alkylene−carbonate−ketone) with molecular weight average Mw of 27.000 (GPC) occurred. No elimination, vinylidene polymerization, or single ring-opening polymerization was detected, as commonly observed in the case of free-radical initiation of similar spiroorthocarbonates, spiroorthoesters, or methylenedioxolanes were detected. Despite quantitative double ring opening, no volume expansion o...