Mechanical properties and reactions of PBT/PTW blends

The new rubbery poly(ethylene-butylacrylate-glycidyl methacrylate) (PTW) containing epoxy groups was used as a toughener for poly(butylene terephthalate) (PBT). The morphology and mechanical property of the PBT/PTW blend was studied. The reactions between PBT and PTW resulted in improvement of toughness, and were affected by the content of PTW. The reaction during the blending process was followed using an internal mixer. The simulated interfacial reaction between PBT and PTW was studied using the ARES rheometer. The complex viscosity curve could be divided into three stages to characterize the interfacial reactions between PBT and PTW at different temperatures. The temperature strongly affected the rates of the interfacial reaction and diffusion. The reaction of the mixture of PBT and PTW in the internal mixer was much faster than that at the simulated interfacial region. Finally, the differences between the simulated interfacial reaction and the reaction during the real processing were discussed.