STONE IMPACT DAMAGE TO PAINTED PLASTIC SUBSTRATES

Through utilization of a ''precision paint collider'' impact damage on varying thermoplastic olefin (TPO), reaction injection molded urethan e (RIM), sheet molded compound (SMC), and Xenoy (a thermoplastic alloy composed of polycarbonate and polybutylene terephthalate) was assesse d via digital imaging analysis of the impacted area. Failures in the i mpact area resulted largely from paint delamination. In the case of TP O, often times cohesive substrate tested, the greater the temperature at which impact was performed, the greater the amount of damage inflic ted upon the substrate. On RIM, however, the opposite occurred. For tw o-component topcoats (those crosslinked with isocyanates), SMC perform ed better than Xenoy, RIM, and TPO, respectively. For one-component to pcoats (those crosslinked with melamine), RIM performed better than TP O. In general, one-component paints afforded better impact resistance than two-component paints.