射线辐照HDPE及其与绢英粉共混体系的流变性能

A STUDY ON THE RHEOLOGICAL PROPERTIES OF GAMMA RAY IRRADIATED HDPE AND ITS BLEND WITH STC

采用高压毛细管流变仪及平行板流变仪研究了γ射线辐照高密度聚乙烯(γ-HDPE)及其与绢英粉(STC)共混体系的流变性能。结果表明,γ射线辐照使HDPE发生氧化降解,导致表观黏度降低;与HDPE/STC共混体系相比,γ-HDPE/t-STC(硅烷偶联剂处理的绢英粉)共混体系的熔体表观剪切应力、表观黏度和HDPE/STC基本相同,出现不稳定流动的临界剪切速率提高。γ-HDPE/t-STC共混体系的复数黏度、储能模量、损耗模量均略高于HDPE/STC共混体系,说明辐照增加了HDPE分子的极性,使HDPE分子链与t-STC粒子之间的界面相互作用增强,从而导致材料力学性能的提高。

The effect of gamma irradiation on the rheological properties of HDPE and its blend with STC was studied through high pressure capillary rheometer and advanced rheometric system (ARES) Rheometrics parallel-plate rheometer. The experimental results show that the apparent viscosity, complex viscosity(η~), storage modulus(G′) and loss modulus (G″) of gamma irradiated HDPE (γ-HDPE) are lower than those of HDPE due to the degradation of molecular chain during irradiation. Compared with that of HDPE/STC blend, the apparent viscosity of γ-HDPE/t-STC (silane treated STC) is almost unchanged. The complex viscosity, storage modulus and loss modulus of γ-HDPE/t-STC blend are a little higher than those of the HDPE/STC blend, which indicates that the interfacial adhesion between γ-HDPE and silane treated STC (t-STC) is strong since some oxygen-containing groups (mainly (C=O) group) are introduced onto the molecular chains of HDPE through gamma ray irradiation in air. Compared with HDPE/STC blend, The yield and notched izod impact strength of m(γ-HDPE)/m(t-STC)(60/40) are increased to (30.6) MPa and 547 J/m from (25.4) MPa and 63 J/m respectively.