In this study the influence of nanoclay and glass fibre in the shrinkage and ejection forces
in polypropylene matrix in tubular parts moulded by injection moulding were analysed. An
instrumented mould was used to measure the part surface temperature and ejection forces in tubular
parts. The materials used were a polypropylene homopolymer Domolen 1100L nanoclay for
polyolefin nanocomposites P-802 Nanomax in percentages of 2%, 6% and 10% and a
polypropylene homopolymer with content of 10% of glass fibre Domolen P1-013-V10-N and 30%
of glass fibre Domolen P1-102-V30-N with 2% of nanoclay. The shrinkage and ejection forces
were analysed. The results show that the incorporation of nanoclays decreases the shrinkage and
ejection forces whereas glass fibre decreases the shrinkage and increase ejection forces due to the
increase of the elastic modulus. The nanoclays decrease the ejection force when compared with
glass fibre and pure PP. The effects of nanoclays are less pronounced than those of glass fibre.
The effect of the mould temperatures on the ejection forces in the mouldings produced with the
mentioned materials were also analysed. The ejection force decreases with the increase of the
temperature of the mould