苯基乙烯基低聚硅倍半氧烷的合成及乙烯基酯树脂复合物的性能

A phenyl and vinyl groups- containing polyhedral oligomeric silsesquioxanes (MPOSS) was synthesized by phenyltrimethoxysilane and methylacryloxypropyltrimethoxysilane, ¹H-NMR, ¹³C-NMR, ²⁹Si-NMR and MALDI- TOF- MS were used to characterize the structure of MPOSS. MPOSS is mainly T10 and T12 cage structure with good thermal stability and high carbon residue. MPOSS was applied to modify vinyl ester resin to produce VER/MPOSS composites, TGA, DSC and mechanical tests show that MPOSS can be crosslinked into vinyl ester resin network structure via free radical polymerization, the thermal stability, char residue and glass transition temperature of VER/MPOSS composites increase with the increase of MPOSS ratio. Compared with pure VER, the bending strength, bending modulus and breaking force of composites with 20% MPOSS added are increased by 203%, 365% and 200% respectively, MPOSS improves the mechanical properties significantly. Limiting oxygen index(LOI), CONE calorimetry (CONE) and TG- FTIR tests show that MPOSS promotes the formation of dense char layer and prevents the release of volatile organic products, thus reducing the heat release, smoke release and toxic gas release of VER, and enhancing the flame retardancy. Therefore, MPOSS has a good application prospect in the modification of vinyl ester resin.