Cr. Kumar et al., Transport of water through polyamide-nitrile rubber blends and its influence on mechanical properties, POLYM POL C, 9(4), 2001, pp. 247-256
Polyamide-nitrile rubber blends of high polyamide content (100/0, 70/30, 50
/50) were prepared by melt mixing in a Haake Rheocord. The diffusion of wat
er through the blends was investigated at various temperatures; 28, 45, 65
and 75 degreesC. The temperature dependence of the diffusion characteristic
s indicates that the transport mechanism varied with blend composition, mor
phology and temperature. The weight gain curves for pure polyamide and blen
ds rich in polyamide showed a maximum followed by a decrease (overshoot eff
ect). The enthalpy and entropy of sorption have been computed from the sorp
tion data. Transport was found to follow the Fickian type mechanism. The ef
fects of water uptake on the mechanical behaviour of the blends have also b
een analysed. The mechanical properties were found to decrease considerably
as a result of water absorption.