Preparation And Properties Of Thermoplastic Polyester Elastomer Composites

Thermoplastic Polyester Elastom(TPEE), a new kind of Thermoplastic Elastom(TPE), consists hard segments(crystalline phase) with high melting point and soft segments(amorphous) with low glass transition temperature. Due to its polarity, rigid and crystalline of hard segmengt, TPEE has good heat resistance, oil resistance and solvent resistance. In addition, the polyether soft segment has low glass transition temperature, which make material with excellent anti-aging performance and mechanical performance.Besides, TPEE have both excellent melt stability, thermoplastic and good processability which can use a variety of thermoplastic processing technology, and quickly developed into a kind of green environmental protection material which solve the problem of the rubber products cannot be reused to a certain extent. Although TPEE has excellent comprehensive performance, but the tensile strength is low which limits its application scope. So it is necessary to improve the tensile strength by modification of TPEE carry out the modification on the premise of guarantee the other properties. Moreover, studying crystallization behavior of crystalline polymer has great research value and significance in both academic and industrial production application. Compared with isothermal crystallization, non-isothermal crystallization is closer to the actual production and processing conditions, and can provide better guidance for the actual production.In this work, we study the crystallization of TPEE composites which prepared by melt blending with diffient partical size, content and type of nano silica.After that, TPEE was modified by melt blending with other nano fillers and ploymer to improve its Tensile Strength. Morphology characterization, Rheology, Dynamic Mechanical Analysis and other kinds of characterization methods was used to study the relationship between structure and properties of composite materials wtih relevant mechanism.(1) TPEE composites were prepared by melt blending with nano silica which modified by the silane coupling agent. X-ray diffraction (XRD) analysis show that the crystal structure of the polymer substrate did not change by addition of nano silica fillier. In the non-isothermal crystallization process, nano silica had obvious heterogeneous nucleation effect to promote the matrix nucleus formation. The modified nano silica increased nucleation temperature more, while the big particle size nano silica increased the crystallization rate of matrix more obvious.(2) Graphene oxide (GO) was successfully prepared by modified Hummers method using improved. Then, GO was reduced by chemical reduction method and modified with 4,4-diphenylmethane diisocyanate (MDI). Finally, the product was characterized by XRD and Raman spectroscopy (Raman) and the results show that graphene nanosheets (GNS)and modified graphene nanosheets (fGNS) have been successfully made.Composites were prepared by melt blending with 0.1% and 1% fillers.Rheology analysis indicates that fGNS has better dispersibility in the matrix materials which provides composites a better Tensile Strength.At the same time, both GNS and fGNS can promote the crystallization of TPEE.(3) Composites were prepared by melt blending with different components of TPEE and Polybutylece Terephthalate.Scanning Electronic Microscope (SEM) and rheology study show that two phase have a good compatibility and the interface bonding between them is hard.Through the test on the properties of composites, we found that the PBT performs a good enhancement effect on TPEE and also TPEE shows a well toughening effects on PBT. When two phase have the same component, the Tensile Strength of composites had increased by 32% compared with pure TPEE, while the Impact Strength of composites had increased by 200% compared with pure PBT.