Study On The Morphological Properties And Microstructure Of Toughened PBT And Mc Nylon

The engineering plastics are widely used in the automotive and electronic industries owning to their excellent properties. Compared with metal, the engineering plastics get conspicuously lower densities and specific strength with decreased energy consumption. On the other hand, when the heat resistance and electrical insulation are required, the engineering plastics are more attractive among the plastics.Nylon plays a leading role in the engineering plastics market due to its excellent general properties and low cost. Among the different kinds of Nylon, monomer casting nylon (Mc Nylon) holds a unique applied field due to its specific casting process. Polybutylene terephthalate (PBT) grows at a top speed among the engineering plastics since its industrialization in the 1970s. As commodity crystallization polymers, PBT and Mc Nylon are both notched sensitive although the high crystallity is helpful for their excellent rigidity and modulus.Blending with the elastomers is an efficient way to toughen plastics. The toughening ways may be various as the different properties of the polymer matrix. Generally, the impact energy is dissipated through the cavitations of elastomer particles and interfaces or the interaction between dispersed phase and the matrix. As a result, the interface status is significant for the performance of polymer blends. The compatibilizers are usually blended directly or in-situ induced to enhance the interface adhesion.In this thesis, the influence of reactivity of different groups on the in-situ reaction at the interface when prepared PBT/ABS alloys through melting extrusion was discussed. We found that the compatibilization with ASMA for PBT/ABS blends was unsubstantial as the low reactivity between ASMA and PBT. The addition of epoxy resin (EP) leads to the formation of the ASMA-EP-PBT graft copolymers that effectively compatibilized PBT/ABS blends. Fine phase morphologies with uniform particle dispersion were obtained. We also studied the linear viscoelastic properties of the blends. The PBT/ABS/ASMA/EP blends presented a more stable "solid-like" melt behavior compared with the blends without EP.Recently, the ultra fine full-vulcanized powdered rubber (UFPR) and core-shell impact modifiers received lots of attentions as the size, structure and the surface properties of these particles can be designed during the preparing process. We studied the modification of Mc Nylon with these particles. DSC study showed that the UFPR particles served as nucleating agents during the crystallization of Mc Nylon. The crystallization rate increased after introducing UFPR. XRD results indicated that the rubber particles did not changed the crystallization form of Mc Nylon. Only a form was observed both in Mc Nylon and modified Mc Nylon. Furthermore, as the mechanical test, we found that Mc Nylon was markedly toughened by the UFPR while its rigidities were kept.