Study On Glass Fiber Modified P(3HB-co-4HB)/PLA Blends

In this thesis, the surface treatment of glass fiber(GF) and effect of glass fiber and chain extender on properties of poly (3-hydroxybutyrate-co-4-hydroxybutyrate)/polylactic acid[P(3HB-co-4HB)/PLA] blends were investigated, as well as the final formula of glass fiber reinforced P(3HB-co-4HB)/PLA blends and the process conditions were determined. Fourier transform infrared spectroscopy(FTIR), differential scanning calorimetric(DSC), electronic universal testing machine, capillary rheometer, melt flow index rheometer, thermo gravimetric analyzer(TGA), vicat softening temperature detector, scanning electron microscope(SEM), etc. were used to determine the mechanical properties, rheological properties, thermal properties, dimensional stability and section shape of composites. The results show that:(1) Glass fiber treated by acid etching, alkali etching, and coupling agent can improve the properties of P(3HB-co-4HB)/PLA blends, but acid etching and alkali etching result in damage of glass fiber surface of different degrees.(2) Glass fiber treated by coupling agent can be dispersed in P(3HB-co-4HB)/PLA matrix and have a great interfacial connection with the matrix.(3) With the addition of IPDI, the compatibility of P(3HB-co-4HB) and PLA was greatly improved, and the melt strength and toughness of composites were also increased.(4) An appropriate amount of glass fibers can significantly improve the mechanical properties of P(3HB-co-4HB)/PLA blends. In the glass fiber content of 30 %to 40%, the tensile strength, flexural strength, notched impact strength and hardness of the composites enhanced about 52.95%,58.63%,61.29% and 58.01%, respectively.(5) Melt viscosity, initial degradation temperature(IDT) and vicat softening temperature of composites were significantly improved by glass fiber.(6) Adding glass fiber also raised the dimensional stability of composites.