Shrinkability of ethylene vinyl acetate/polyurethane blends and their characterization

Abstract

Heat shrinkability of the polymer, which depends on the elastic memory, is being utilized in various applications, mainly in the field of encapsulation. The elastic memory is introduced into the system in the form of an elastomeric phase. Here the blends of ethylene vinyl acetate and polyurethane were studied with reference to their shrinkability, introducing crosslinking in both the phases. It is found that with increase in elastomer content the shrinkage increased to a certain level and then decreased. With increase in cure time shrinkage is decreased. It is seen that high‐temperature (HT) stretched samples showed higher shrinkage than room temperature (RT) stretched one. Generally, the crystallinity of the HT stretched sample is higher than that of low‐temperature stretched sample, which is again higher than that of original sample. From high temperature differential scanning calorimetry it is found that with increase in PU content stability towards oxygen is increased and further high temperature processing decreases the initial degradation temperature but enhances the rate of degradation. From scanning electron microscopy it is seen that an HT stretched sample is more elongated than an RT stretched one. Copyright © 2000 John Wiley & Sons, Ltd.

Development of recyclable electron beam radiation crosslinked LDPE/‘EVA-embedded nanoclay’ nanocomposites

“…10 For pure LDPE and LE73 blends in presence and absence of clay, peak positions of polymer crystals and half width remained unchanged, which led to the conclusion that crystal type and crystallite sizes were unchanged. 16,17 Total amount of crystallinity was also almost same. After irradiation at 100 kGy doses there was no change of crystallinity and crystal type.…”

ENGAGE compatibilized HDPE/EPDM blends: Modification of some industrially pertinent properties and morphology upon incorporation of Mg(OH)2 filler and electron beam crosslinked network

“…The d ‐space, crystallite size ( P ), and interchain distance ( r ) of neat, unirradiated, and irradiated blends and composites are calculated as follows where K is considered here as 0.90 and λ is 1.54 Å wavelength of Cu X‐ray source.…”

Self-Reinforcing Composite Based on Ethylene Acrylic Elastomer (AEM)/Liquid Crystalline Polymer (LCP) Blend

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