Introduction to the anti-ageing properties of plastic products for automobiles

Most automotive plastic products are made from polymer resins that are thermally processed and moulded. Polymer resins are microscopic monomers that are formed by chain polymerisation, addition or condensation, with thousands of microscopic units linked together to form polymer resin compounds with large molecular chain segments.

The resin is then shaped and prepared in several processes into variously shaped parts for automotive use, a process in which the polymer resin is subjected to thermal and mechanical shear, and the subsequent use of the resin, which is accompanied by erosive damage from oxygen, heat, light and water.

Under these damaging conditions, microstructural changes such as oxidative breakage, chain branching or chain cross-linking of the resin's molecular chains can occur, resulting in defects such as degradation of the material's macroscopic properties, discolouration and even cracking.

This damage can be inhibited or delayed by structural modification of the polymer resin or by the addition of anti-ageing additives, where oxidative degradation is more important than pure thermal degradation at lower temperatures, and where the damage to the macroscopic properties of the material is greatest.