Non-aqueous sol–gel synthesis of epoxy-functionalized and epoxy and vinyl-functionalized poly (borosiloxane) s

摘要: Boric acid (BA) was reacted with 3-glycidyloxypropyltrimethoxysilane (GPTMOS) in diethylene glycol dimethyl ether, 1,4-dioxane or without using any solvent under reflux condition to obtain epoxyborosiloxane resins. A gelled product was obtained irrespective of solvent (1,4-dioxane/diethylene glycol dimethyl ether) used when BA and GPTMOS were reacted in 0.5:1 mole ratio followed by the removal of solvent and methanol (byproduct) by flash evaporation. Epoxyborosiloxane resins soluble in common organic solvents and having epoxy value of 3.8–4.2 eqv/kg were obtained when BA and GPTMOS were reacted in 0.5:1.5 mole ratio in 1,4-dioxane followed by flash drying or freeze drying. These resins leave behind ceramic residue of 39–44% at 800 °C in inert atmosphere as indicated by thermogravimetric analysis. Epoxyborosiloxane resin exhibiting of 4070 and of 1600 and epoxy value of 4.4 eqv/kg was …