Scratch-healable automotive clearcoats
A new paper reports a novel scratch-resistant and healable automotive clearcoat that can not only protect the substrate surface but also facilitate scratch repair.
A self-healable disulfide polyurethane diol adduct (DSPUDA) was synthesised via step-growth polymerisation with bis(4-hydroxyphenyl) disulfide, isophorone diisocyanate, and poly(tetrahydrofuran).
Sufficient mechanical properties
The mechanical properties of the clearcoat surfaces were investigated using nano-indentation and pendulum hardness tests. The healing efficiency and mechanical properties of the prepared clearcoats exhibited an inverse trade-off relationship. Nevertheless, optimising the proportion of reversible disulfide bonds of the DSPUDA in the polyacrylate-based urethane networks not only resulted in superior scratch healing and scratch resistance but also maintained sufficient mechanical properties for the coatings to be used as automotive clearcoats.
The study has been published in Progress in Organic Coatings, Volume 161, December 2021.