Radiation crosslinked Polyolefinic blends: exploring thermally tuned dual Shape Memory character

Abstract

Shape memory behavior of thermally triggered polymeric materials based on ethylene octene copolymer (EOC) and ethylene propylene diene rubber (EPDM) has been studied in details. Investigation of the shape memory behavior of uncrosslinked EOC–EPDM and electron beam crosslinked EOC–EPDM blends have been pursued thoroughly. Shape memory study has been carried out at 60°C, which shows that with the effect of electron beam radiation shape fixity behavior of the crosslinked blends becomes poor as compared with its uncrosslinked blend system whereas the improvement in shape recovery behavior takes place after the exposure to electron beam radiation. Morphology study by Atomic Force Microscopy (AFM) and crystallinity study by X-ray diffraction analysis also give the clear idea regarding the formation of crosslinked network structure. Improvement in gel content with increasing radiation dose supports the formation of network structure. Even after the crosslinking in presence of electron beam radiation also, it has been found that crosslinked EPDM rich blends is superior in terms of shape memory behavior point of view. Lower decay of stress value coupled with lower relaxation ratio of crosslinked EPDM rich blend support its superior shape memory behavior. Copyright © 2016 John Wiley & Sons, Ltd.