Modification of epoxy resin with diphenyl silanediol and its thermal stability

Modification of epoxy resin with organic silicone is an effective method to prepare the new thermosetting epoxy resin with high thermal stability, low shrinkage, and good mechanical properties. Diphenyl silanediol and bisphenol A epoxy resins (E-44) were used to prepare the silicone-epoxy resins and the cured materials. The chemical structure and thermal mechanical properties of the modified resins were characterized by thermal mechanical analyzer (TMA), thermogravimetric analysis (TGA), infrared spectroscopy (IR), etc. The optimized synthesis conditions are determined by the orthogonal and single-factor experimental design as molar ratio (diphenyl silicone diol/E-44) (1:4), reaction temperature (110°C), and reaction times (2 hours). The results show that the coefficient of thermal expansion and thermal stress parameter of the diphenyl siliconediol modified epoxy resins decrease 33.2% and 36.3% respectively, the decomposition temperature increase 15°C and the glass transition temperature has no significant decline compared with those of unmodified epoxy resin, exhibiting good thermal stability.