Scratch resistance of mineral‐filled polypropylene materials

Pigmented mineral‐filled polypropylene (PP‐PMF) is marketed as a potential alternative to acrylonitrile‐butyldiene‐styrene (ABS) and Polycarbonate/ABS for automotive interior components. PP‐PMF is more easily damaged by surface scratch/mar, thus limiting its acceptance for such applications. This study focuses on investigating the scratch/mar mechanisms of PP‐PMF having different mineral fillers and additives. A new method is introduced to characterize the scratch visibility by image analysis. A correlation is found between scratch visibility and scratch hardness measured by interferometer. It is found that Wollastonite filler imparts higher scratch/mar resistance. Addition of an interface modifier and a lubricant can further improve scratch/mar resistance. It is also found that Talc‐filled PP‐PMF has poor scratch/mar resistance, irrespective of the addition of an interface modifier or a lubricant.