A. Amash et P. Zugenmaier, Morphology and properties of isotropic and oriented samples of cellulose fibre-polypropylene composites, POLYMER, 41(4), 2000, pp. 1589-1596
Thermal, morphological and dynamic mechanical properties of polypropylene (
PP)-cellulose fibre (CF) composites were investigated. Two types of CF and
a compatibilizer were used. Calorimetric measurements exhibited an increase
in the crystallization temperature and crystallinity of the PP component.
This is attributed to the nucleating effects of the fibre surfaces, resulti
ng in the formation of transcrystalline regions observed by an optical meth
od. The dynamic mechanical spectra of the composites revealed an increase i
n the stiffness and a reduction in the damping values with an increasing CF
content. The results are consistent with morphological observations, which
verify an improved interfacial adhesion between fibre and matrix. The effe
cts of drawing on the structure and physical properties of PP-CF composites
were also studied. Increasing draw ratio, the melting peak of PP component
was shifted to higher temperatures suggesting a constrained melting, and t
he uniaxial elastic modulus was considerably enhanced. The biggest influenc
e was observed for the samples of PP-spun cellulose and the lowest for neat
PP. In addition to the fibrillar structure of the oriented PP, the highly
CF orientation and the efficient compatibilization in composites are respon
sible for the effects observed in the drawn samples. (C) 1999 Elsevier Scie
nce Ltd. All rights reserved.