Novel Cost-effective Alternative to Conventional Flame Retardant Styrenic Alloy Formulations (PPT)

摘要

Historically, electronic enclosures have been manufactured from high-impact polystyrene (HIPS) or acrylonitrile-butadiene-styrene (ABS) resins mainly due to their inherent properties allowing for lower cost-in-use while maintaining a necessary performance level. However, advancements in display technology have driven to more demanding resin requirements. A growing trend in this market is to alloy HIPS and ABS with more thermally stable and mechanically robust resins such as polyphenylene ox ide (PPO) and polycarbonate (PC), respectively, to provide a compounded final product with enhanced thermal-mechanical and flammability properties than that of solely HIPS or ABS. Current PPO/HIPS and PC/ABS solutions use phosphate esters as flame retar-dants due to the difference in cost-in-use between phosphorous flame retardant (PFR) vs. brominated flame retardant (BFR) alloys, caused by escalating antimony trioxide (ATO) pricing increasing the BFR solution cost. A major disadvantage of the PFR solution for styrenic alloys is the limitation it imposes on the styrenic loading of these alloys, due to their plasticizing nature and lower FR efficiency compared to BFRs. Use of BFRs could potentially increase the use of HIPS or ABS, thereby reducing the overall cost of the base resin alloy, with the likelihood of also minimizing or eliminating the use of ATO. The present invention provides flame retardancy to PPO/HIPS and PC/ABS styrenic alloys through incorporation of a polymeric BFR with and without the use of ATO andpolytetrafluoroethylene (PTFE). Key points of understanding were developed for the relationships between the chosen independent variables to gain knowledge regarding optimal additive loadings.