2,2′-双(2-噁唑啉)扩链尼龙6的研究

Study on the Chain Extension of PA6 with 2,2′-bis(2-oxazoline)

对2,2′-双(2-噁唑啉)(BOZ)作为扩链剂用于尼龙6的加成型化学扩链做了系统的研究,同时分析了扩链前后尼龙6的热性能和力学性能变化。结果表明,扩链剂用量存在最佳值。用量不足时,偶联反应不充分;用量过量时,封端反应加剧;当扩链剂的加入量为最佳值时,扩链后PA6的特性粘度从1.384 dl/g增加到1.636 dl/g,端羧基含量降低为初始值的40%左右;噁唑啉环在高粘熔体中的扩散速率是扩链反应的一个重要影响因素;扩链后尼龙6的结晶度有所下降,扩链后尼龙6在湿态条件下的缺口冲击强度、断裂伸长率和拉伸强度都有较大的提高。

A systemic study was performed for the chemical chain extension of Polyamide 6 （ PA6 ） in the mode of addition reaction with taking 2,2＇ -his（2 -oxazoline） as chain extender. It had been shown that there existed an optimal dosage of chain extender, lack of which caused deficiency of chain extension and excess of which led to more blocking reaction. When the optimum amount of chain exten.der was added in PA6, the intrinsic viscosity of chain - extended of PA6 increased from 1. 384 dL/g to 1. 636dL/g. At the same time, the carboxyl end - group concentration of the chain - extended PA6 decreased to 40% of initial carboxyl content of PA6. The diffusion rate of the oxazoline ring in melting PA6 was an important factor for the extent of chain extension. The degree of crystallinity decreased as the chain extender was added in PA6. Furthermore, the resultant products of Izod impact strength, tensile strength and elongation at break had dramatically improved under wet conditions.