不同增容剂对PUR-T/亮氨酸复合材料性能的影响

采用硅烷偶联剂KH–560、环氧树脂E44两种不同的增容剂改性热塑性聚氨酯(PUR-T)/亮氨酸(Leu)复合材料,利用核磁共振氢谱(1H-NMR)仪、傅立叶变换红外光谱(FTIR)仪对PUR-T的结构进行表征,通过万能试验机、X射线衍射(XRD)仪和热重(TG)分析仪对复合材料的性能进行测试。结合分子模拟技术,探讨了PUR-T与Leu的界面作用。研究结果表明,FTIR谱图中出现PUR-T的特征峰,说明合成的PUR-T为目标产物,1H-NMR谱图中的化学位移也证明了这一结果。当PUR-T/Leu=80/20,KH–560,E44添加量均为1%时,两种改性复合材料的力学性能显著提高,断裂伸长率分别提高了14.7%,5.3%,拉伸强度分别提高了6.1%,7.7%。此外,KH–560和E44中的—OH与Leu中的—OH形成H—O…H—O,同时与PUR-T相互吸附,形成C=O…H—O氢键作用,促使PUR-T与Leu间的界面结合增强,KH–560和E44增容改性的PUR-T/Leu复合材料的混合能和Flory-huggins相互作用参数均低于未改性复合材料,体系可混合性明显提高。

Influences of Different Compatilizers on Thermoplastic Polyurethane/Leucine Composites

Thermoplastic polyurethane elastomer (PUR-T)/leucine (Leu) composites were modified by two different com-patibilizers which included silane coupling agent KH–560 and epoxy resin E44. Nuclear magnetic resonance spectrometer (1H-NMR) and Fourier transform infrared spectrometer (FTIR) were employed to characterize the structure of PUR-T. Universal testing machine,X ray diffractometer (XRD) and thermogravimetric (TGA) analyzer were used to analyze the properties of composite. Besides,the interfacial interaction between PUR-T and Leu was further investigated by molecular simulation technique. The experi-mental results show that when the ratio of PUR-T and Leu is 80:20 and the content of compatibilizer KH–560 and E44 is 1%,the mechanical properties of two composites were significantly improved. The elongations at break increase by 14.7% and 5.3%,respec-tively. The tensile strengths of the composites increase by 6.1% and 7.7%,respectively. Moreover,there exists formation of H—O…H—O between —OH of PUR-T and —OH of KH–560,and then form adsorption with PUR-T. Hydrogen bonding of C=O…H—O is formed,which can enhance the interfacial bonding between PUR-T and Leu. E44 can form H—O…H—O with Leu and C=O—H—O with PUR-T. The mixing energy and Flory-huggins interaction parameters of KH–560 modified PUR-T/Leu composite are the lowest in three systems and the mixing ability of the system is improved obviously. The mixing energy and Flory-huggins interac-tion parameters of E44 modified PUR-T/Leu composite are the lower than unmodified PUR-T/Leu composite,which illustrates the interface compatibility is improved.