Thermoplastic Toughening of Semiaromatic Polyamides Using Amine-terminated Polyethylene
Semiaromatic commercial polyamides can be used for metal replacement in advanced engineering applications, as a way to decrease total weight and improve efficiency. However, they often suffer from an inherent lack of ductility. Here, we have incorporated amine-terminated polyethylene (PE) into semiaromatic polyamide HT1 using high-temperature melt blending, which we have envisaged to serve as a thermoplastic toughener. We have investigated the resulting materials microstructure and properties in comparison to materials blended with non-functional PE or the commercial impact modifier styrene-ethylene-butylene-styrene (SEBS). This analysis shows that significantly smaller and more uniform PE domains are present in the amine-terminated composition, resulting in superior mechanical performance.
Glass fibers are widely used to reinforce polyamides when increasing stiffness and strength are required; for this reason, we have reinforced our PE/polyamide materials with glass fibers and have observed a similar property profile to the of aliphatic polyamide PA6 with glass fibers. The primary advantage of our composite materials over a reinforced PA6 is the thermal stability of the matrix due to a higher melting temperature.