改性聚丙烯再生料的非等温结晶动力学研究  

Study on Non-Isothermal Crystallization Kinetics of Polypropylene Modified with Recycled Material

作　　者：张仲荣 赵一权 李明贺 谢宇 ZHANG Zhongrong;ZHAO Yiquan;LI Minghe;XIE Yu(CATARC Component Technology(Tianjin)Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]中汽零部件技术(天津)有限公司,天津300300

出　　处：《上海塑料》2024年第4期8-17,22,共11页Shanghai Plastics

摘　　要：采用差示扫描量热仪研究了再生料改性聚丙烯(PP)的样品在4种不同降温速率下的非等温结晶行为,采用Jeziorny法、莫志深法、Friedman法、Kissinger法分析了PP的非等温结晶动力学。结果表明:随着PP再生料在PP中的质量分数从0%递增至50%,PP结晶峰温度逐渐降低,半结晶时间变短;随着降温速率的上升,结晶温度下降,结晶时间缩短,结晶速率提高。采用Jeziorny法分析得出在初期相对结晶度为5%以内时,Avrami指数n在4附近;当相对结晶度为5%~50%且降温速率在5~20 K/min时,Avrami指数n为4~6,而当降温速率为40 K/min时,n则回落到4附近。采用莫志深法分析得出随着相对结晶度的增大,各PP的F(T)均增大,结晶速度降低,而相同相对结晶度下各PP之间的F(T)基本相近,结晶速度大致相当,PP再生料的添加对相对结晶度没有影响。采用Friedman法分析得出随着相对结晶度的增大,活化能增大,在相同相对结晶度下,PP再生料对于活化能有一定影响,表现为随着PP再生料添加质量分数从10%增加至50%,活化能呈现下降趋势,结晶温度稍有提高。采用Kissinger法分析得出随着PP再生料的添加,表观活化能略有增加。The non-isothermal crystallization behavior of polypropylene(PP) modified by recycled materials was studied by differential scanning calorimeter at 4 different cooling rates.The non-isothermal crystallization kinetics of PP was analyzed by Jeziorny method,Mo Zhishen method,Friedman method,and Kissinger method.The results showed that the crystallization peak temperature of PP gradually decreases and the semi-crystallization time shortens as the mass fraction of PP recycled materials in PP increases from 0% to 50%.With the increase of cooling rate,the crystallization temperature and crystallization time both decrease,and the crystallization rate increases.The results of Jeziorny method showed that Avrami index(n) of PP is about 4 when relative crystallinity is less than 5%.When the relative crystallinity ranges from 5%-50%,Avrami index(n) is between 4 and 6 for cooling rates with 5-20 K/min,and Avrami index(n) is about 4 for 40 K/min.The results of Mo Zhishen method showed that the F(T) value of each PP increases and the crystallization rate decreases with the increase of relative crystallinity,and at the same relative crystallinity the F(T) is similar and the crystallization rate is approximately the same,so the addition of recycled materials has no effect on the crystallinity.According to Friedman method results,the activation energy increases with the increase of crystallinity,and at the same relative crystallinity the PP recycled material has a slight effect on the activation energy,and with the increase of the content of recycled PP from 10% to 50%,the activation energy decreases and the crystallization temperature increases a little.Kissinger method results showed that the apparent activation energy of the sample increases slightly with the addition of PP recycled material.

关 键 词：聚丙烯 再生料 DSC 非等温结晶动力学 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]