Why ABS Plastic Products Turn Yellow After Prolonged Use

  The yellowing of ABS plastic products over time results from material degradation processes influenced by several factors. Primarily, this discoloration occurs due to oxidation accelerated by exposure to heat, moisture, and ultraviolet light. During normal use, ABS components often experience thermal exposure from electrical operation, and when combined with humid   conditions, this environment promotes accelerated oxidation leading to both yellowing and embrittlement.

The manufacturing process itself can contribute to this problem when injection molding parameters are not optimized. Excessive residence time in the barrel or elevated processing temperatures beyond the recommended range (typically 60-70°C) can initiate material degradation during production.

  ABS possesses inherently poor UV resistance and limited antioxidant capacity, making it particularly susceptible to yellowing when exposed to sunlight or outdoor environmental conditions. Even high-quality ABS formulations will exhibit noticeable yellowing after extended light exposure without adequate stabilizers.

Many white ABS products incorporate whitening additives such as titanium dioxide to achieve their bright appearance. However, these additives can degrade under prolonged UV exposure, losing their whitening effect and resulting in irreversible yellowing that cannot be reversed to the original white state.

Preventive measures include selecting UV-stabilized ABS grades for applications with light exposure, optimizing processing parameters to minimize thermal degradation, and implementing proper storage conditions that shield products from direct sunlight and heat sources.