聚己内酯的水热老化性能的研究

Hydrothermal Aging Properties of Polycaprolactone

以可降解塑料聚己内酯(PCL)为研究对象,对比研究了其在30、40和50℃三种不同温度下的水热老化降解性能,包括水热老化对其质量、力学性能、热稳定性能及熔融性能的影响。结果表明:随着水热老化的进行,PCL的质量起初略有增加,当水热老化到一段时间后,质量下降,特别是在50℃、水热老化450 min后,PCL的质量显著下降;外观照片显示,50℃水热老化510 min后,试样表面,特别是边缘部位,发生熔化现象;水热老化将导致PCL弯曲强度下降,但不能改变其韧性断裂的特征;反而在40℃或50℃水热老化510 min后,试样表现出比未老化试样更加优异的断裂伸长性能;水热老化将降低PCL的热稳定性,但对试样的熔融峰位置影响不大。结论:PCL可以采用热塑性塑料常规的加工工艺进行加工成型,但不适宜在50℃的水热环境中长期使用。

The degradable plastic,polycaprolactone(PCL),was chosen as the object,its degradability after hydrothermal aging at different temperatures were investigated,including the effects of hydrothermal aging on the mass,mechanical and thermal properties of PCL.The results show that,with the proceeding of hydrothermal aging,the mass of each specimen increases slightly at first,then decrease,especially after hydrothermal aging at 50℃for 450 min,the mass of PCL reduced dramatically,which is due to the melting on surface,especially at edge,as evidenced in photographs.The flexural strength of PCL will be slightly reduced when hydrothermal aged,while its flexible properties won’t be changed,on the contrary,the elogation at break will be better after being aged at 40℃or 50℃.The thermal stability of PCL will be worsened after hydrothermal aging while the temperature corresponding to the melting peak changes very little.Conclusion:PCL can be processed using the common processing methods for thermoplastics,but can’t be used in the hydrothermal environment at 50℃for a long time.