Flammability and Thermal Properties of Polyamide 11-Alumina Nanocomposites

Neat polyamides 11 and 12 lack high strength/high heat resistance and flame retardancy. The incorporation of selected nanoparticles is expected to enhance these properties to a level that is desired and required for performance driven applications. This enhancement may result in additional market opportunities for the polyamide 11 and 12 polymer manufacturers. The objective of this study is to develop polyamide 11 polymer nanocomposites with enhanced thermal, flammability, and mechanical performance for selective laser sintering (SLS) rapid manufacturing. Three types of nano-alumnia (X-0 needle, X-25SR, and X-0SR) with different organic treatments were melt-compounded into polyamide 11 in three different weight loadings of the nanoparticles (2.5%, 5%, and 7.5%). Injection molded specimens were fabricated for thermal, flammability, and mechanical properties characterization. Although nano-alumina was uniformly dispersed in polyamide 11 and better thermal stability of the nanomodified materials was observed, the desired FR characteristics of the nanomodified polyamide 11 was not achieved. None of the materials passed the desired UL 94 V0 rating.