耐热聚乙烯管材专用树脂的结构与性能

Structure and properties of PE-RT special resins for pipe use

研究了3种耐热聚乙烯管材专用树脂的结构与性能。它们的共同特征为熔体流动速率低于0．7g／10min，密度为0．930～0．944g/cm3，相对分子质量为（1．5～2．5）×10^5，可以为窄相对分子质量分布，也可以为中等相对分子质量分布。1-己烯共聚产品与1-辛烯共聚产品性质较为接近，都是窄相对分子质量分布，而1-丁烯共聚产品具有相对分子质量高（2．0×10^5以上），相对分子质量分布中等（10左右），熔体流动速率低（低于0．3g／10min）、密度高（大于0．940g／cm3）、拉伸屈服强度高、弯曲模量高、熔融峰温高、结晶峰温高的特点。相同条件下，1-丁烯共聚产品具有较高的黏度和模量。

The structure and properties of three kinds of thermo-resistant polyethylene （PE-RT） special resins for pipe use were studied. These three PE-RT materials commonly features melt flow index below 0.7 g/10 rain, density of 0.930-0.944 g/cm3, relative molecular mass of （1.5-2.5） × 10^5 and narrow or middle relative molecular mass distribution. The 1-hexene copolymerized products have properties similar to those of the 1-octene copolymerized products, and both have narrow relative molecular mass distribution. The 1-butylene copolymerized products have characteristics of high relative molecular mass （above 2.0 × 10^5）, middle relative molecular mass distribution （about 10）, low melt flow index （below 0.3 g/10 min）, high density （over 0.940 g/cm3）, high tensile strength at yield, high flexural strength, high peak melting temperature, high peak crystallization temperature, high viscosity and high modulus under the same conditions.