1. Introduction
Polypropylene is the third most consumed polymer right after PVC and PE. This low-cost material has numerous advantages, such as a high modulus, excellent chemical resistance and easy conversion.
The addition of low-cost fillers such as calcium carbonate or talc was historically justified by the cost reduction; however, performance improvements and other benefits brought by the use of these materials are the cause of its increasing use in polypropylene systems. This explains why the use of this polymer has such significantly grown in automotive or appliances applications.
What is a filler?
A filler is a material based on insoluble particles (spheres, lamella, fibre...) chemically inert at polymer processing temperature. Fillers are mainly used to reduce cost and /or improve certain performance of the polymer (mechanical, electrical, chemical...). The yearly consumption of mineral filler in plastic industry reaches about 12 millions Mtons; Calcium carbonate is the most often used filler in plastics in general; Talc is the most common one in polypropylene systems.