Sr. Chowdhury et Ck. Das, Structure-shrinkability correlation in polymer blends of ethylene vinyl acetate and chlorosulfonated polyethylene, J APPL POLY, 78(4), 2000, pp. 707-715
Heat shrinkability, which is a collective Property of polymers, is being ut
ilized in various applications, mainly in the field of encapsulation. Elast
ic memory is introduced into the system in the form of an elastomeric phase
. Here the blends of ethylene vinyl acetate and chlorosulfonated rubber wer
e studied with reference to their shrinkability. It was found that an incre
ase in the elastomer content increased the shrinkage and an increase in cur
e time also increased the shrinkage. It was seen that high temperature (H-T
) stretched samples showed higher shrinkage than the low (room) temperature
(R-T) stretched one. Generally, the crystallinity of the H-T stretched sam
ple was higher than that of the low temperature stretched sample, which was
again higher than that of the original unstretched sample; but for the low
elastomer content blend the crystallinity of the R-T stretched sample was
found to be greater than the corresponding H-T stretched one. The H-T diffe
rential scanning calorimetry showed that an increase in the CSM content cau
sed the stability toward oxygen to increase. The first decomposition temper
atures were found to be higher and the second decomposition temperatures ap
peared to be lower for the H-T shrunk sample than the corresponding unstret
ched sample. The rate of degradation appeared to be enhanced initially, the
n after 50% decomposition the rate started going down compared to the usual
unstretched sample. From SEM it was seen that the H-T stretched sample was
more elongated than the R-T stretched one. (C) 2000 John Wiley & Sons, Inc
.