尼龙6固相缩聚及结构性能研究

Study on solid state polycondensation and property of nylon 6

对萃取后的尼龙6切片进行了固相缩聚以提高其相对黏度(η_r),研究了不同反应时间和温度对增黏效果的影响。采用乌式黏度计、端基滴定法、热重分析法(TGA)、X射线衍射法(XRD)和毛细管流变仪对样品进行了测试。实验结果表明,尼龙6切片的热稳定性基本不变,切片所含晶型只有α单斜晶系,并未出现晶型的转变,出现了晶面的择优取向生长现象。在反应温度为190℃,反应时间为12h时,固相缩聚后的尼龙6切片相对黏度达到3.2,初始分解温度为412.3℃,最大分解温度为469.5℃,性能得到提高。

To increase the relative viscosity of extractive nylon 6 pellets,the solid state polycondensation（SSP）was used.The influence of different time and temperature was studied by ubbelohde viscometer,end group analysis process,thermogravimetric analyses（TGA）,X-ray diffraction（XRD）and capillary rheometer.The results showed that changes of relative viscosity and end-group concentration were evident at the first 6 hours.During the process,there was little change of the thermostability.In the nylon 6 pellets there was onlyαcrystalline phase and no new crystalline phase appeared,but a phenomenon called preferred orientation growth occurred.The relative viscosity could be 3.2 at 190℃ after 12 h.The primary thermal decomposition temperature was 412.3℃ and the maximum decomposition temperature was 469.5℃.The performance was enhanced.