基于二硫键的自修复水性聚氨酯的制备与性能研究

以芳香二硫化合物2，2'?二氨基二苯二硫醚（AD）为原料，制备了一种自愈性水性聚氨酯（WPU）材料。利用全反射傅里叶变换红外光谱仪、拉曼光谱仪、热失重分析仪、粒径分析仪、热台偏光显微镜和接触角仪对改性材料进行了结构表征与性能测试，探讨了聚氨酯材料的热稳定性、表面疏水性、自修复性能的变化。另外，通过拉伸测试，定量评价了材料的拉伸性能和自愈合效率。结果表明，AD成功引入到WPU分子链中；随着AD含量的增加，改性材料的热稳定性逐渐下降；表面疏水性提升，样品WPU?3的静态接触角达到了81.2 °；拉伸强度由WPU?0的1.1 MPa增至WPU?3的5.6 MPa；同时，在中等愈合温度（80 ℃）下，样品WPU?1加热3 h后可以使拉伸应变的愈合效率达到81 %左右。

Preparation and properties of self?healing waterborne polyurethane based on disulfide bonds

A series of self?healing waterborne polyurethane materials （WPUs） was prepared using a aromatic disulfide compound， 2，2'?diaminodiphenyldisulfide （AD）， as a raw material. The resulting WPUs were characterized using FTIR spectrometer， Raman spectrometer， thermogravimetric analyzer， particle size analyzer， hot?stage polarized light microscope， and contact angle meter. Their thermal stability， surface hydrophobicity and self?healing properties were investigated together with its tensile properties and self?healing efficiency evaluated quantitatively though a tensile experiment. The results showed that AD was successfully introduced into the molecular chain of WPUs. The thermal stability of WPUs decreased gradually with an increase in AD content， and its surface hydrophobicity increased as well. The sample WPU?3 presented a static contact angle of 81.2 ° and tensile strength of 5.6 MPa. However， WPU?0 only has tensile strength of 1.1 MPa. On the other hand， WPU?1 has a tensile strain healing efficiency of 81 % after heating for 3 h under a moderate healing temperature of 80 ℃.