Assessment of the Shrinkage and Ejection Forces of Reinforced Polypropylene Based on Nanoclays and Short Glass Fibre

Abstract

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.

Experimental study of shrinkage and ejection forces of reinforced polypropylene based on nanoclays and short glass fibers

“…This work aims to investigate the effect of glass fibers and nanoclays on the shrinkage and ejection forces in the injection molding process [22][23][24] being this a critical issue when using this processing technique since the force required to eject the part from the mold is a fundamental design variable that defines the project of the ejection system [2,16,25].…”