The Heat Resistance Modification Of Polypropylene And The Influence Of Out-of-Phase Particles On Crystallization Of Polybutylene-1

This paper was divided into two parts. In the first chapter, the process of the heat resisting modifying was researched, mainly through the enhanced modification. The PP/glass fiber aggregates were prepared by using twin-screw extruder. The standard samples of PP/glass fiber aggregates were injected by the plastic injection machine. Then the mechanical properties and the heat resistant performance of composite were tested;Through the mechanical properties, heat resistance test, the tensile strength, bending modulus and vicat softening point of resin A was the best in the three kinds of resin, while toughness was not the best. With the addition of1.2wt%auxiliaries D, the toughness and the heat resistant of resin A were improved. When the glass fiber was added into the resin A matrix, composite had the mostIn the second chapter, the influence of talcum powder, carbon black (CB) and Montmorillonite (MMT) on the melting behavior and crystallization behavior, crystal morphology, crystallization kinetics and crystal transformation of polybutylene-1(PB-1) were studied by DSC, POM and XRD. The results were as follows:The intercalation phenomenon of MMT in PB did not happen. The addition of MMT promoted the shifting process of the crystal Ⅱ to crystal I of PB-1.The MMT was dispersed better in the matrix, the crystal had the higher rate of changing. The MMT acted as a out-of-phase nucleation agent, and to a certain extent it can improve the crystallization ability of PB-1. The influence degree of crystallization and melting behavior was different with the addition of components. As the MMT added to the PB-1, the crystallization nucleation rate of high temperature was observably improved and the perfection degree of spherulite was improved. PB-1originally had a high crystallization nucleation rate in the low temperature, while with the appropriate addition of MMT in the matrix, the quantity of crystal nucleus was obviously increased. Because of dense crystal nucleus, crystals attended by crowd and the deformation happened. With the addition of PP-g-MAH, the nucleation rate of PB was increased greatly, and the crystallization performance of the composites was improved.The crystallization process of PB-1was significantly promoted by1wt%general talcum powder, the crystallization temperature increased by5.4℃, ΔHc increased by2.7J.g-1, melting temperature increased by2.7℃, ΔHm increased by6.4J.g-1. When talcum powder increased from1wt%to10wt%, the crystallization temperature and melting temperature basically unchanged, but AHc and ΔHm reduced. It demonstrated that talcum powder had an impact on the nucleation of PB-1studied by POM, but the pattern of nucleation and three-dimensional growth mechanism of spherulite remained the same. XRD research showed that the crystal transformation of polybutylene-1was slightly promoted by talcum powder, the crystal transformation from Ⅱ to I was completed at55h after processing.The crystallization process of PB-1was significantly promoted by0.5wt%carbon black, increasing the crystallization temperature, improving the ΔHc and melting temperature. When carbon black increased from0.5wt%to3wt%, the crystallizing temperature was slightly increased with increase in carbon black content, the ΔHc changed a little. It demonstrated that carbon black had an obvious impact on the nucleation of PB-1studied by POM, and in some systems, the pattern of nucleation changed, but the three-dimensional growth mechanism of spherulite remained the same. XRD research showed that the crystal transformation of polybutylene-1was not promoted by carbon black. The crystal transformation from Ⅱ to Ⅰ was completed mostly at55h after processing.