Characterization of toughened bonded interface against fracture and impact loads

Joining components of polymer composites through adhesive bonds is becoming increasingly popular. Since the strength of adhesively bonded interface is not high, the interface is designed to be of a large area in most cases. The interface of widely used adhesives like epoxy-based Epibond 1590 A/B is inherently brittle and therefore it is susceptible to fail through fracture. In this study, adhesive Epibond 1590 A/B is modified to make the interface tough by adding a small percentage of high molecular weight carboxylated acrylonitrite butadiene (XNBR). The interface is studied for four candidate proportions 0%, 5%, 7.5% and 10% of XNBR for determining toughness under static and dynamic loading conditions. Modes I and II fracture toughnesses are determined under static conditions and impact-induced damage area of the interface under impact conditions. The Epibond 1590 A/B adhesive modified with 7.5% XNBR by weight gives the best performance for the three properties studied.