Failure Analysis Case Studies in Plastic UV Stabilization

Plastics are ubiquitous worldwide in sectors such as consumer goods, construction, transportation, oil and gas, and beyond. Plastics for outdoor use can be damaged by ultraviolet (UV) light, which induces generation of free radicals that damage constituent polymers via chain scission and cross-linking. These UV-induced reactions cause oxidation, embrittlement, and discoloration. Typically, manufacturers mitigate these harms by including UV-blocking additives such as calcium carbonate and/or additives that react with and neutralize free radicals such as hindered amine light stabilizers (HALS) and antioxidants (AOx). We regularly encounter clients who need assistance in evaluating premature failures of products due to UV-induced degradation. This talk will utilize several case studies that demonstrate the type of issues our clients encounter when they develop and/or commercialize plastics intended for outdoor use. For example, understanding difficulties in formulating HALS for use in thin films, investigation of UV-induced discoloration, and more. For each case study, we will provide a synopsis of what was at stake for the client, describe the relevant polymer formulation, and summarize the steps we took to investigate the observed failures.