废旧聚酯纺织品的再生扩链改性研究

Chain extension modification of recycled post-consumer polyester fabric

以均苯四甲酸二酐(PMDA)为扩链剂,对废旧聚酯纺织品(Post-PET)进行扩链改性,将PMDA与Post-PET按不同配比在Hakke转矩流变仪中进行反应挤出,制备了不同PMDA含量的扩链改性PET(RPET),研究了反应挤出工艺条件及R-PET的性能。结果表明:反应挤出最佳工艺条件为PMDA(相对PostPET)质量分数0.9%,反应温度280℃,反应时间300 s,转速40 r/min,在此条件下制得的R-PET的特性黏数为0.784 d L/g,端羧基含量为67.1 mol/t;与Post-PET比较,R-PET的差示扫描量热曲线中出现了熔融双峰,热失重曲线表明R-PET的热稳定性能没有明显降低;动态流变性能表明,R-PET具有明显的剪切变稀现象,其复数黏度、储能模量、损耗模量均高于Post-PET,满足了R-PET加工对于熔体粘弹性的要求。

Post-consumer polyester （ Post-PET ） fabric was exposed to chain extension modification with pyromellitic dian-hydride （ PMDA） as a chain extender and to reactive extrusion in different proportion from a Hakke torque rheometer to produce chain extension modified PET （ R-PET） with different PMDA content .The reactive extrusion process conditions and the proper-ties of R-PET were studied.The results showed that R-PET could be produced with the intrinsic viscosity of 0.784 dL/g and the carboxyl end group content 67.1 mol/t as the process conditions were optimized as followed：0.9%PMDA based on Post-PET by mass fraction, reaction temperature 280 ℃, reaction time 300 s, rotation speed 40 r/min;double melting peaks appeared in the differential scanning calorimetric curve of R-PET, and the thermal stability of R-PET did not obviously drop as compared with Post-PET;R-PET exhibited the obvious shear thinning phenomenon and higher complex viscosity , storage modulus and loss mod-ulus than Post-PET, and possessed the melt elasticity satisfying the processing requirements .