HDPE超大口径双壁波纹管专用树脂的设计

Design of HDPE speciality resin for double wall corrugated pipe with ultra-large diameter

针对超大口径双壁波纹管的特定性能设计了高密度聚乙烯（HDPE）专用树脂7800M，并进行了产品质量认证。设计7800M的重均分子量为（3．0～4．5）×10^5，相对分子质量分布为双峰模式，分布值为40～60；共聚单体选用1-丁烯．且分布在高相对分子质量级分。质量认证结果表明：7800M设计合理，产品实现了高刚性与优异的耐环境应力开裂（ESCR）性能的合理均衡，其弯曲模量在1400MPa以上，ESCR（‰）在1000h以上，可满足超大尺寸管材制品对材料的要求。性能指标符合GB／T19472．1—2004中对埋地排水管专用树脂的要求。

A kind of high density polyethylene （HDPE） speciality resin 7800M for double wall corrugated pipe with an ultra-large diameter and particular performance was designed; the quality of the speciality resin was authenticated. 7800M possessed bimodal relative molecular mass distribution, Mw of （3.0 - 4.5）×10^5 and M/M. of 40 - 60. 1-butylene was taken as comonomer that was distributed in the fractions with high relative molecular mass. The quality authentication confirms that the design of 7800M is rational. The equilibrium between high stiffness and environmental stress crocking resistance （ESCR） in 7800M is realized advantageously. Having flexural modulus over 1 400 MPa and ESCR over 1 000 h, 7800M can satisfy the requirements of the material suitable for making pipes with ultra-large dimension and complicated shape. The performance of the pipes made of 7800M can meet the specification of the speciality resin for underground structured-wall pipe stipulated in national standard GB/T 19472.1-2004 of China.