The use of plastics in different applications, such as automotive interiors and consumer electronics, has increased mainly due to their low density and light weight, convenient processability and balance of cost and performance. However, many plastics require a coating to protect the surface from scratches and abrasion to maintain their surface appearance and quality. This is particularly challenging in low gloss coatings (≤ 5 gloss units at 60°) where the film damage is easily visible. The thin films used also limits the ability of some additive technologies to improve coating durability.
This paper presents a study of different synthetic silica matting agents in combination with other additives in four different plastic coating formulations and compares their effects on scratch and abrasion resistance of the final coating. Conventional silica matting agents offer good dispersibility and matting efficiency, but their scratch and abrasion resistance does not meet end-user expectations. Organic / polymeric matting agents have better scratch and abrasion resistance but are less efficient in matting. Combinations of silica matting agents with other technologies, such as nylon powders or polyethylene waxes can dramatically improve the scratch resistance without side effects. Abrasion resistance can be enhanced using combinations of matting agents with novel small-sized, spherical silica particles..
