Thermally induced twin polymerization of 4H-1,3,2-benzodioxasilines.
The twin monomer 2,2'-spirobi[4H-1,3,2-benzodioxasiline] (1) can be polymerized to nanostructured SiO2/phenolic-resin composite material by thermally induced twin polymerization. Thermally induced twin polymerization represents a way to produce nanocomposites simply by thermal induction of twin monomers. Besides 1, the thermal reaction of several related salicylic (2-oxybenzylic) silicon molecules has been investigated. The thermal cleavage of the molecules is studied by using several trapping reagents (e.g., vinyl compounds). A significant occurrence of quinone methide adducts indicates that the thermal mechanism proceeds not only by a ring opening at the oxymethylene position, but also with the ortho-quinone methide as a central or alternative intermediate. This is supported by product analyses of thermally initialized reactions of 1 and its substituted analogues as well as by quantum chemical calculations.
Department of Polymer Chemistry, Chemnitz University of Technology, Strasse der Nationen 62, 09111 Chemnitz (Germany), Fax: (+49) 371-531-21239.
Patrick
P
Kempe
Tina
T
Löschner
Alexander A
AA
Auer
Andreas
A
Seifert
Gerhard
G
Cox
Stefan
S
Spange
nanostructures; polymerization; quinones; ring-opening polymerization; silicon