| The goal of this dissertation was to study the properties and morphology in the glass fiber (GF) reinforced polypropylene(PP) composites. It contributed to severals compatibilizers which were efficient on improving the morphology and mechanical properties of GF/PP composites.Polypropylene (PP) was one of the most important general-purpose polymers widely used in various fields such as automobile industry, electric appliances, packing and construction industry etc. But poor toughness and brittleness in low temperature of PP restricts its application. GF is an important inorganic material of excellent properties, for instance, high-strength, high-modulus and the low price, which was proved to be the reinforcement. The main problem of preparation of GF/PP composite was poor mechanical properties because GF and PP was incompatibility. Because of importance of GF and PP in practice, compose of the two materials containing specific properties were both theoretical and practical issues.PP-MAH, BMI, PP-MAH/BMI, PP-AMH/MMA and PP-MAH/MDI could promote the mechanicl properties of GF/PP composites. PP-MAH and BMI could produce the chemical bond and hydrogen bond in the interface to improve the interfacial adhesion respectively. PP-MAH/BMI, PP-MAH/MMA and PP-MAH/MDI could make synergistic effect to improve the interfacial adhesion.The results were obtained by studying the influence of compatibilizer on the morphology, mechanical properties and melt flow rate of GF/PP. Now our work as follow:(1) The results showed that the tensile strength of GF/PP composites reached the maximum value when the content of GF was30%, while the impact strength reached the maximum value when GF content was20%. The MFR of the composite was decreased as the addition of GF. DSC depicted that the degree of crystallinity was increased, which attributed to the heterogeneous nucleation by the addition of GF. SEM showed that plenty of GF extracted in the interface of GF/PPcomposites, which illustrated the interfacial incompatibility of GF and PP.(2) The PP-MAH additives were able to enhance the interfacial adhesion as the compatibilizer. The tensile strength of the GF/PP-MAH/PP composites was increased obviously while the impact strength and MFR had little change. But the content of PP-MAH exceeded5%, the mechanical properties had not increased. The addition of BMI showed the tensile strength of composite increased a little, the impact strength and MFR changed little. When PP-MAH/BMI was added to the GF/PP composite as the compound compatibilizers, the tensile strength and MFR were increased sharply while the impact strength had no obvious change. The properties were excellent as the content of compatibilizers was0.8%.(3) The PP-MAH/MMA or PP-MAH/MDI additives were able to enhance the tensile strength sharply while the impact strength showed little change as the compound compatibilitizers. The tensile strength was maximum value when the content of MMA and MDI were0.8%and1.0%respectively. As the MMA and MDI content increased, MFR of composites were increased and decreased respectively.(4) Compared to the morphology of different additives compatibilizing GF/PP composites, a little resin adhered to GF in the interface of GF/PP-MAH/PP and GF/BMI/PP composites, while plenty of resin adhered to GF in the interface of GF/PP-MAH/BMI/PP, GF/PPMAH/MMA/PP and GF/PP-MAH/MDI/PP composites. It revealed that the compatibility of composites with compound copatibilizers were the best.(5) Compared to the degree of crystallity of additives compatibilizing GF/PP composites, PP-MAH and MMA availed the heterogeneous nucleation in the GF/PP composites while BMI and MDI blocked GF nucleated in the composites.(6) According to above result, compatibilizing mechanism was discussed primarily, major factor include:PP-MAH and BMI could produce the chemical bond and hydrogen bond in the interface to improve the interfical adhesion respectively. PP-MAH/BMI, PP-MAH/MMA and PP-MAH/MDI could produce synergistic effect to improve the interfical adhesion. |
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