r-PTFE对PBT非等温结晶动力学的影响

Effect of Recycled PTFE on Non-isothermal Crystallization Kinetics of PBT

以回收聚四氟乙烯(r-PTFE)为成核剂,对聚对苯二甲酸丁二醇酯(BPT)进行成核结晶改性,采用差示扫描量热仪(DSC)研究了PBT/r-PTFE复合材料的非等温结晶行为,考察了不同降温速率对PBT/r-PTFE共混物结晶行为的影响,并对其DSC扫描数据采用Jeziorny法和Liu-Mo法进行处理,采用Kissiinger法计算体系结晶活化能。结果表明:r-PTFE对PBT具有异相成核作用,可明显提高PBT的结晶度及其结晶速率,且加入r-PTFE并不会改变PBT的成核和增长方式。由Kissinger法计算得出的结晶活化能结果表明,加入r-PTFE树脂能够明显降低PBT的结晶活化能,进一步验证r-PTFE对PBT具有成核促进作用。

The recycled polytetrafluoroethylene（r-TPFE）was used as nucleating agent to modify Poly（butylene terephthalate）（PBT）,and the non-isothermal crystallization behavior of Poly（ethylene terephthalate）and PBT/r-PTFE composite at different cooling rates was investigated by differential scanning calorimetry（DSC）,respectively.The Jeziorny and Liu-Mo methods were used to analyze the non-isothermal crystallization process of pure PBT and its composite,and the activation energies of the PBT and PBT/r-PTFE composite were calculated by Kissiinger method.The results show that rPTFE can act as efficient nucleating agent for the crystallization of PBT and obviously increase the crystallinity and crystallization rate of PBT.Compared with the Jeziorny method,the Liu-Mo method appropriately describes the non-isothermal crystallization of PBT and PBT/r-PTFE composite.Further analysis of results shows that the incorporation of r-PTFE does not obviously change the nucleation mechanism and crystal growth of PBT,but decreases the crystallization activation energy of PBT,which facilitates the crystallization of PBT.