Effect of the coupling agent's reactivity on the shrinkability of the blends consisting of grafted poly (ethylene vinyl acetate) and polyurethane elastomer

Blend prepared by the melt mixing of thermoplastic elastomer has gained con siderable attention in recent years from heat shrinkability point of view. Present study deals with the measurement of the heat shrinkability of the m aleic anhydride grafted poly (ethylene vinyl acetate) and polyurethane elas tomer blend. Two samples have been prepared to study the effect of the coup ling agent's reactivity on the shrinkability of the blend. The used couplin g agents are 4,4 ' diamino diphenyl sulphone (DDS) and 4,4 ' diamino diphen yl methane (MDA). It is revealed that heat shrinkability increases as the r eactivity of the coupling agent increases. The reactivity as well as the sh rinkability is more when the used coupling agent is 4,4 ' diamino diphenyl methane. The mechanism of interchain crosslinking reaction is confirmed by IR spectroscopy. (C) 2001 Elsevier Science B.V. All rights reserved.