通过注塑工艺制备无规共聚聚丙烯(PP–R)样条，并将样条置于热处理设备进行退火处理。运用差示扫描量热仪、广角X射线衍射仪、偏光显微镜和扫描电子显微镜等方法，分析了退火对PP–R的结晶行为和力学性能的影响。结果表明，退火可以消除热应力，促进结晶的完善，使得PP–R的结晶度从41.2%提高到48.4%，诱导β晶的生成，能有效改善材料的力学性能。退火使得PP–R的拉伸强度有所提高；对冲击性能影响明显，在25℃时，PP–R的冲击强度从41.67 kJ／m2提高到66.84 kJ／m2，提高了60.4%；在0℃时，PP–R的冲击强度从11.54 kJ／m2提高到32.68 kJ／m2，提高了1.8倍。%Random copolymer polypropylene (PP–R) sample was prepared by injection molding process. The samples were put into heat treatment equipment for annealing treatment. The effects of annealing treatment on crystallization behavior and mechanical properties of PP–R were analyzed by differential scanning calorimetry,wide-angle X ray diffraction, polarizing optical microscope and scanning electron microscope. The results show that annealing can eliminate thermal stress and promote crystallization,making crystallization of PP–R increased form 41.2% to 48.4% to induce β crystals forming, thus can effectively improve the mechanical properties of PP–R. Annealing makes tensile strength of PP–R increase. Annealing has a great influence on impact strength of PP–R,which increases from 41.67 kJ/m2 to 66.84 kJ/m2 going by 60.4%at 25 ℃ and increases from 11.54 kJ/m2 to 32.68 kJ/m2 going 1.8 times at 0℃.
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