CROSS-LINKING COPOLYMERIZATION OF EPOXY METHACRYLATES AS STUDIED BY FOURIER-TRANSFORM RAMAN-SPECTROSCOPY

Bisphenol-A-bis(2-hydroxypropyl methacrylate) (BisGMA) was copolymeriz ed with methyl derivatives of styrene initiated by di-tert-butyl perox ide in the presence of 76 wt% of silica filler at 150 degrees-200 degr ees C. The Raman bands of the C=C stretching vibrations at 1630 and 16 37 cm(-1) were found to be suitable for determining the conversion of C=C double bonds of the styrene and the methacrylate monomer simultane ously in dependence on the copolymerization time. The C=O Raman band o f the BisGMA monomer at 1702 cm(-1) vanishes during the copolymerizati on, whereas the intensity of the C=O band at 1718 cm(-1) decreases. Co pyright (C) 1996 Elsevier Science Ltd.