The Effect of Salt Splash on Nylon 6,6

One of the most common environmental exposures that nylon undergoes, when used for automotive applications, is that of salt splash, which commonly occurs during winter driving. This study looks at the effect of various salts (NaCl, KCl, CaCl2) on the thermal and mechanical properties of nylon when exposed to one and four molar aqueous salt solutions. It was found that the diffusion of salt solutions into nylon 6,6 occurred in a pseudo-Fickian manner. Also, it was found that the presence of salt had an effect on the rate of decrease of yield stress with increasing exposure time. The presence of residual salt was found to accelerated deterioration of nylon 6,6, possibly via hydrolysis. In addition, it was found that residual salt was left after water was removed from the system and that this salt was removable.