Poly(2,6-dimethyl-1,4-phenylene ether)/poly(phenylene sulfide)/styrenic block copolymer blends compatibilized with reactive polystyrene

Abstract

Blends of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and poly(phenylene sulfide) (PPS) have shown potential as a new class of high-performance engineering plastics by reciprocally complementing the drawbacks of each component. However, improving their inherently poor toughness remains a challenge. Here, we report the design of PPE/PPS-based quaternary blends with increased impact strength without a significant loss of mechanical and flame-retardant properties. Introducing reactive polystyrene (RPS) with an oxazoline functional group as a compatibilizer improved the miscibility between the discrete PPE domain and continuous PPS matrix phases. The impact modifier styrene-ethylene-butadiene-styrene (SEBS) was compatibilized within the PPS matrix phase in the presence of RPS, enabling extraordinary impact strength. The tensile strength of the quaternary blends decreased slightly with increasing SEBS content, but the values exceeded the criteria for engineering plastic. All quaternary blends passed the V-0 grade in the UL-94 test because of the inherently excellent flame retardancy of the majority components.