Silicone-epoxy block hybrid network to achieve high-performance and transparent polydimethylsiloxane materials

The preparation of highly compatible polydimethylsiloxane/epoxy system has been a challenging task. Here, we designed and synthesized a vinyl-containing bifunctional epoxy resin, which was chemically bonded with polydimethylsiloxane by hydrosilylation. A silicone-epoxy block hybrid network with restricted micromorphology and outstanding macro-performance was formed. The phase separation scale of polydimethylsiloxane/epoxy system was strictly restricted by molecular structure design and the modified PDMS was transparent. The mechanical test results showed that the tensile strength, elongation at break and shear strength of the hybrid material were increased by 391%, 78% and 292% respectively. More importantly, the initial thermal decomposition temperature of the hybrid material increased, and its thermal residue at 800 °C was kept at a high level. All these results indicate that we have prepared a transparent, high-performance polydimethylsiloxane material, which is expected to be applied in many prospects such as heat resistant adhesive and transparent surface coating.