Thermoplastic polyamide (PA) elastomers (TPAE) modified with terephthalic acid (PTA) were synthesized withε-caprolactam (CPL),PTA and polytetramethylene-oxide glycol (PTMG) through a one-step melt polymerization. PTA was used as the molecular weight control agent to replace the traditional adipic acid. Instrinsic viscosity and chemical structure were investigated by means of ubbelohde viscometer,FTIR and1H-NMR. The thermal properties were investigated by differential scanning calorim-etry (DSC) and thermogravimetric (TG) analysis. X-ray diffraction (XRD) results characterized the crystalline structure of the TPAE-modified by PTA. Meawhile,the mechanical properties were tested. The results of FTIR and1H-NMR show that the TPAE modified by PTA are successfully synthesized. The results of DSC show that the minimum melting temperature is 96.1℃and the maximum is 193.5℃. The TG results indicate that the 5% weight loss temperature is above 369℃ when the PA hard segment content higher than 35%. XRD results show that the crystallization of the TPAE increases with the content of PA hard segments increase. Moreover,the largest breaking strength and elongation at break are 0.901 cN/dtex and 1123.1%,respectively.%采用熔融缩聚法,以ε-己内酰胺(CPL),对苯二甲酸(PTA)和聚四氢呋喃醚二醇(PTMG)为原材料合成了一系列具有酰胺结构的PTA改性热塑性聚酰胺(PA)弹性体(TPAE).其中PTA是用来代替传统己二酸作为分子量控制剂.采用乌氏黏度计测试了PTA改性TPAE的特性黏度,通过傅立叶变换红外光谱(FTIR)、核磁共振氢谱(1H-NMR)确定PTA改性TPAE的分子结构,通过差示扫描量热(DSC)法、热重(TG)分析仪测试分析了PTA改性TPAE的热性能,采用X射线衍射(XRD)仪表征了PTA改性TPAE的结晶性能,同时还测试了PTA改性TPAE纤维的力学性能.通过FTIR和1H-NMR分析表明,成功合成了PTA改性的TPAE.DSC分析结果表明,合成的PTA改性的TPAE最低熔点为96.1℃,而最高可达到193.5℃.TG分析结果表明,当PTA改性TPAE中PA硬链段含量高于35%时,PTA改性TPAE的起始分解温度(失重5%)均高于369℃.XRD分析结果显示,随着PTA改性TPAE中PA硬链段含量的增加,即PTA含量的下降,PTA改性TPAE的结晶性能相应增加.由力学性能数据可知,合成的PTA改性的最大断裂伸长率为1123.1%,最大断裂强度为0.901 cN/dtex.
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