摘要
采用热重分析法测定了在氮气气氛中5℃/min、10℃/min、15℃/min和20℃/min不同升温速率下的石蜡、保形聚合物(PP与HDPE的混合物)、石蜡/保形聚合物和碳化钨(WC-10%Ni)粉末注射成形专用料的热解过程,采用Kissinger法和Flynn-Wall-OZAWA法对4种专用料的热分解动力学进行分析,并用Coats-Redfern研究反应级数。结果表明,用Kissinger法分析不能很好地反映混合物的复杂的热解过程,不能支持碳化钨粉末注射成形一步热脱脂的工艺制定。用Flynn-Wall-OZAWA法分析,石蜡的热分解活化能在59~72 k J/mol,保形聚合物的热分解活化能在143~252 k J/mol,石蜡/保形聚合物的热分解活化能在60~240 k J/mol和WC-10%Ni的专用料的热分解活化能在93~220 k J/mol。用CoatsRedfern法分析,石蜡与保形聚合物的热解可用一级反应来描述,而石蜡/保形聚合物与WC-10%Ni的专用料的热解则适用3个连续一级反应来描述。
In this paper,the decomposition process of paraffin waxes,conformal polymers( mixtures of PP and HDPE),paraffin/conformal polymerization( PP/HDPE) and tungsten carbide( WC-10% Ni) Ni powder injection molding feedstock was analyzed by thermogravimetric methodin nitrogen at four different heating rates( 5 ℃/min,10℃/min,15 ℃/min and 20 ℃/min). The thermal decomposition kinetics of these four materials was analyzed by Kissinger method and Flynn-Wall-OZAWA method,and the reaction order was studied by Coats-Redfernformulation. The results show that the Kissinger method does not reflect the complex pyrolysis process of the mixture welland can not support the one-step thermal debinding process of tungstencarbide powder for feedstock injection molding. Determined by Flynn-Wall-OZAWA method,the pyrolysis activation energy of paraffin wax,conformal polymer,paraffin/conformal polymer and tungsten carbide( WC-10% Ni) nickel powder injection molding feedstock is respectively 59 ~ 72 k J/mol,143 ~ 252 k J/mol,60 ~ 240 k J/mol and 93 ~ 220 k J/mol respectively. The pyrolysis of paraffin and conformal polymers can be described by the first order reaction,while the mixture of paraffin/conformal polymer and WC-10% Ni is described by three successive first-order reactions.
作者
刘春林
史安康
吴盾
陆颖
张钱鹏
刘刚
Chunlin Liu;Ankang Shi;Dun Wu;Ying Lu;Qianpeng Zhang;Gang Liu(Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials,School of Materials Science and Engineering,Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering,Changzhou University,Changzhou 213164,China)
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2018年第7期107-113,共7页
Polymer Materials Science & Engineering
基金
江苏省产学研联合创新资金-前瞻性联合研究项目(BY2016029-06)
关键词
热重分析法
活化能
动力学
碳化钨
thermogravimetric analysis
activation energy
kinetics
tungsten carbide