Reactions of some anhydride-containing copolymers with gamma-aminopropyltriethoxysilane

This work describes the synthesis and macromolecular reactions of maleic an hydride (MA)-methyl methacrylate (MMA) binary and MA-trans-stilbene (Stb)-n -butyl methacrylate (BMA) ternary reactive copolymers with gamma -aminoprop yltriethoxysilane (APTS) as a polyfunctional crosslinker. Copolymers with g iven compositions of MA-MMA (77.7 mol%) and MA (22.7 mol%)-Stb-BMA (54.2 mo l%) are synthesised by radical binary and ternary copolymerisations with be nzoyl peroxide as an initiator in toluene at 70 degreesC and initial monome r ratios 1:4 and I:1:1, respectively. It is shown that the network structur e is formed in MA-MMA/APTS and MA-Stb-BMA/APTS in methyl ethyl ketone (MEK) solutions by intermolecular reactions between the anhydride unit and the a mine group, as well as between the ethoxysilyl fragment and the free carbox yl group formed after the amidisation of the anhydride unit. Swelling param eters, such as the beginning time of xerogel-formation, initial rate of swe lling and equilibrium swelling, are determined for the copolymer/APTS/MEK s ystem with various polymer/crosslinker ratios. Formation of a hyperbranched network structure through the fragmentation of side-chain reactive groups in the studied systems is confirmed by FTIR, TGA and DSC methods. (C) 2001 Published by Elsevier Science Ltd.