Composition-dependent properties of polyethylene/Kaolin composites - Part II - Thermoelastic behaviour of blow-moulded samples

Samples of the blow-moulding grade HDPE filled with Kaolin were characteriz ed by wide-angle X-ray scattering, microhardness and stretching calorimetry techniques. It is shown that crystallinity of the polymer matrix in the fi lled samples remains essentially the same as that in the neat polymer regar dless of the filler content. The thermoelastic behaviour of all samples bel ow the apparent yield point epsilon* is quantitatively described by classic al equations for elastic solids. The thermoelastic parameters of the bounda ry interphase (BI) are discussed in terms of predictions of the step-by-ste p averaging approach. The experimental values of the internal energy increm ent in the inelastic strain interval for unfilled and filled samples are an alyzed in the light of the filler debonding processes in the latter. (C) 19 99 Kluwer Academic Publishers.