HDPE/Na_(2)SO_(4)复合材料的热降解动力学研究  

ThermalDecomposition Kinetics of HDPE/Na_(2)SO_(4) Composites

作　　者：谢锦辉 严伟[2] 尚晓煜 孙俊卓 谭芳 宝冬梅[1] 秦舒浩 张道海[1] XIE Jinhui;YAN Wei;SUN Junzhuo;SHANG Xiaoyu;TAN Fang;BAO Dongmei;QIN Shu Hao;ZHANG DaoHai(School of chemical engineering,Guizhou University for nationalities,Guiyang 550025;School of chemistry and materials engineering,Guiyang University,Guiyang 550002;National EngineeringResearch Center for Compounding and Modification of Polymeric Materials,Guiyang 550014)

机构地区：[1]贵州民族大学化学工程学院,贵阳550025 [2]贵阳学院化学与材料工程学院,贵阳550002 [3]国家复合改性聚合物材料工程技术研究中心,贵阳550014

出　　处：《塑料工业》2023年第S01期55-62,共8页China Plastics Industry

基　　金：国家自然科学基金项目(52163001,51863004);贵州省科学技术基金项目(黔科合基础[2020]1Y211);贵州民族大学科研平台资助项目(GZMUGCZX[2021]01);贵州省2018年度高层次创新型人才培养-千层次人才项目(项目负责人:宝冬梅);贵阳市专家工作站(ZJGZZ2021-07);贵阳市白云区科技计划项目(白科合同[2019]34号,白科合同[2020]28号,白科合同[2019]21号)。

摘　　要：利用硅烷偶联剂(KH570)改性Na_(2)SO_(4) 填充高密度聚乙烯(HDPE)制备HDPE/Na_(2)SO_(4) 复合材料。通过TG-DTG方法分析复合材料的热降解过程;利用Kissinger法、Flynn-Wall-Ozawa法及Coast-Redfern 方程分析HDPE/Na_(2)SO_(4) 复合材料的非等温热降解动力学数据,计算其活化能、指前因子并推测热降解反应机理及动力学方程。结论显示:(1)Na_(2)SO_(4) 的掺杂提升了HDPE/Na_(2)SO_(4) 复合材料的残炭量及初始降解温度和峰温值,并产生热滞后效应。(2)HDPE/Na_(2)SO_(4) 复合材料样品(9-1,8-2,7-3,6-4,5-5,HDPE)通过Kissinger法计算出活化能为240.262kJ/mol,229.104 kJ/mol,225.723 kJ/mol,238.885 kJ/mol,256.021 kJ/mol,244.110 kJ/mol;lgA K 分别为19.485,18.669,18.497,19.382,20.549,19.648;FWO法对应的平均活化能为:234.57 kJ/mol,235.08 kJ/mol,228.19 kJ/mol,225.03 kJ/mol,189.50 kJ/mol,262.8 kJ/mol;而 Coast-Redfern 方程得到HDPE/Na_(2)SO_(4) 复合材料热降解机理函数为g( α )=[-ln(1- α )] 3/4 ,反应级数=3/4,热降解机理为随机成核和随后生长反应。HDPE/Na_(2)SO_(4) composites were prepared by filling HDPE with silane coupling agent KH570 modified sodium sulphate(Na_(2)SO_(4)).Then,TG-DTG method was used to analyze the thermal degradation process of the composites.Also,Kissinger method,Flynn-Wall-Ozawa method and Coast-Redfern equation were used to analyze the non-isothermal thermal degradation kinetics of the composites.In this way,the activation energy and preexponential factor of the composites were calculated,and the reaction mechanism and kinetic equation were deduced.And the results show that:(1)The doping of Na_(2)SO_(4) increases the carbon residue,initial degradation temperature and peak temperature(maximum decomposition temperature)of HDPE/Na_(2)SO_(4) composites,resulting in thermal hysteresis effect.(2)The activation energies of composites HDPE/Na_(2)SO_(4)(9-1,8-2,7-3,6-4,5-5,HDPE)calculated by Kissinger method are 240.262 kJ/mol,229.104 kJ/mol,225.723 kJ/mol,238.885 kJ/mol,256.021 kJ/mol,244.110 kJ/mol,respectively.And the lgA K are 19.485,18.669,18.497,19.382,20.549 and 19.648,respectively.Also,the corresponding activation energies of FWO method are 234.57 kJ/mol,235.08 kJ/mol,228.19 kJ/mol,225.03 kJ/mol,189.50 kJ/mol and 262.8 kJ/mol.Moreover,the Coast-Redfern equation obtains the thermal degradation mechanism function of HDPE/Na_(2)SO_(4) composite as g(α)=[-ln(1-α)]3/4,reaction order=3/4.And the thermal degradation mechanism is random nucleation and subsequent growth reaction.

关 键 词：高密度聚乙烯 硫酸钠 热降解动力学 活化能 指前因子 复合材料 

分 类 号：TQ325.1[化学工程—合成树脂塑料工业]