IN-SITU COMPATIBILIZATION OF PBT ABS BLENDS THROUGH REACTIVE COPOLYMERS/

Styrene-acrylonitrile-glycidyl methacrylate (SAG) copolymer with ethyl triphenyl phosphonium bromide (ETPB) catalyst has been used successful ly as in situ compatibilizer to compatibilize the immiscible and incom patible blends of poly(butylene terephthalate) (PBT) and acrylonitrile -butadiene-styrene (ABS). This SAG copolymer contains reactive glycidy l groups that are able to react with PET end groups (-COOH or -OH) und er melt conditions to form SAG-g-PET copolymer. However, the rate of t he grafting reaction is slow without the presence of catalyst. The ETP B catalyst is highly efficient: even at a concentration as low as 50 p pm, it is able to promote the grafting reaction to obtain the maximum achievable properties. The compatibilized PBT/ABS blend has smaller ph ase domain, higher viscosity, and significantly improved mechanical pr operties compared to the corresponding non-compatibilized blend.