Abstract:

Photo-curable silicone materials combine the advantages of photo-curing by high efficient, energy saving and low impact on environment in application with the excellent heat and weather resistance, and electrical insulation properties of silicone materials. In this work, the photocuring behaviors, the optical properties and thermal stability of the cured materials of a series of photo-curable phenyl-silicone prepolymes (KDS-10, KMDS-03, KMS-03) are studied. It has been found that the refractive index increases with the increasing of phenyl units in the silicone prepolymer: when the phenyl content increased from 22.3% to 37.7%, the refractive index of the prepolymer increased from 1.496 of KMS-03 to 1.542 of KDS-10. The silicone prepolymers are well compatible with acrylate diluents. The photo-curing mixture exhibits higher curing rate and vinyl conversion with difunctional TPGDT as the diluents. TPO is the most efficient photoinitator in curing rate and conversion. The photo-cured film prepared by prepolymer KDS-10 shows excellent optical properties with transmittance over 92.54% at 550 nm and excellent thermal stability with the initial thermal degradation temperature of 385℃ with glass transition temperature about-17.4℃.

Key words: silicone, prepolymer, UV-curing, sealing, device