The effect of weathering and thermal treatment on the scratch recovery characteristics of clearcoats

Abstract

The scratch and scratch recovery characteristics of two clearcoats, a polyurethane and an acrylic/ melamine/silane clearcoat, were measured by a variety of methods. On most size scales tested, the polyurethane possessed superior scratch and mar resistance. The polyurethane also possessed improved scratch recovery after warming for 2 h at 60°C. After 2000 h of accelerated weathering, the scratch recovery characteristics of the polyurethane were largely maintained, while the acrylic/melamine/silane showed a significant drop in scratch recovery performance. Performance of both coatings was related to T g , hardness, and crosslink density.

Synthesis and characterization of nanosilica ball—PMMA hybrid composites

“…The scratch resistance of the clearcoats was evaluated using a nanoscratch tester (Open Platform CSM Instruments, Switzerland) and Amtec‐Kistler car‐wash tester (Amtec, Germany) 32, 33. The nanoscratch testing method is a reproducible quantitative technique in which critical loads at which failures appear are used to compare the cohesive and adhesive properties of coatings.…”

An Overview of the Scratch Resistance of Automotive Coatings: Exterior Clearcoats and Polycarbonate Hardcoats

“…This healing is thought to occur due to reflow of the coating into the damaged area. Specific formulations of polyurethane clearcoats have the ability to recover between ~80%-90% of the scratch/mar's shoulder height and trough depth compared to current acrylic/melamine/silane formulations which recover between ~35%-60% [18]. While these thermally healing coatings have been shown to reduce the shoulder and trough heights/depths of mars/scratches, they cannot heal any cracks that occur during fracture scratch events.…”