通过差示扫描量热仪、拉伸性能、冲击性能、弯曲性能和负荷变形温度测试，研究不同β成核剂对低熔体流动速率均聚聚丙烯性能影响，筛选出综合性能优异的改性低熔体流动速率均聚聚丙烯，并与市场同类产品对比。结果表明：β成核剂的加入使低熔体流动速率均聚聚丙烯发生晶型转变，材料常、低温冲击和负荷变形温度提高。其中，α晶的熔融温度和结晶温度升高，形成的β晶是冲击性能改善的原因；当β成核剂添加量为500 mg/kg时，冲击强度最高可达98.9 kJ/m²，提升390%；稀土类β成核剂改性低熔体流动速率均聚聚丙烯具有良好的综合性能。

The influence of various β nucleating agents on low melt flow rate homopolymer polypropylene was studied through differential scanning calorimeter, tensile properties, impact properties, bending properties, and heat distortion temperature testing, to identify a modified low melt flow rate homopolymer polypropylene with excellent comprehensive properties which was compared with similar products in the market. The results showed that the crystallization form was transformed due to the addition of nucleating agents, and the impact resistance of the materials at both ambient and low temperatures, as well as its load-deformation temperature, have been improved. Wherein, the melting temperature and crystallization temperature of α crystallization increased, and the formation of β crystallization was the reason for the improvement of the impact properties. When the addition of β-nucleating agent was 500 mg/kg, the impact strength could reach as high as 98.9 kJ/m², representing an increase of 390%. The low melt flow rate homopolymer polypropylene modified by rare earth β-nucleating agents exhibits excellent comprehensive properties.