Abstract
Synthesis and properties of novel siloxane-modified epoxy resins (ESDGs) were studied. These epoxy resins were synthesized by the reaction of bisphenol-A type epoxy resin having allyl group with hydride terminated polydimethylsiloxanes. ESDGs were mixed with a commercial epoxy resin (DGEBA) in various ratios. The mixed resins were cured with triethyleneglycoldiamine. The effect of the amount of siloxane units on toughness, heat-resistance and adhesive properties of cured resins were investigated. The addition of 10wt% ESDG resulted in a 40% increase in the toughness (Klc) without reducing heat resistance. SEM showed that the improvement depended on the microphase-separated structure. Peel strength of adhesives were improved by the addition of ESDG.
