含动态二硫键与硅氧键的环氧树脂复合材料的制备与表征

Preparation and characterization of epoxy composites containing dynamic disulfide and silicon-oxygen bonds

作为一类新兴的聚合物材料,类玻璃高分子(vitrimer)由于其交联网络中含有可动态交换的可逆共价键,可在外加刺激下展示出动态的特性而不影响交联网络的完整性,从而既具有热塑性材料的可加工性又具有热固性材料的交联结构,能够减少塑料废弃造成的环境污染和资源浪费,因而备受关注。为了有效改善因热固性环氧树脂不可回收而造成的环境问题,通过一锅法将硅氧键和二硫键引入环氧树脂交联网络,制备了一系列含双重动态共价键的多壁碳纳米管(MWCNTs)/vitrimer复合材料(EPGCSLx)。研究了MWCNTs不同掺杂量下材料的导电性、热力学性能、自修复性能、再加工和可降解性。结果表明,EPGCSL5(MWCNTs质量分数为5%)具有良好的导电性(电导率为2.09 S/m)和力学性能(拉伸强度为8.12 MPa,断裂伸长率为84.67%)。EPGCSL5还具有可再加工性、可降解性和光热性能,充分结合了vitrimer和环氧树脂复合材料的优点。此外,EPGCSL5被制备成人体运动传感器,证明了其作为运动传感器的应用潜力。

As emerging class of polymer materials,due to its crosslinked network contains reversible covalent bonds that can be stimulated to display dynamic properties without affecting the integrity of the crosslinked network,vitrimer has both the processability of thermoplastics and the crosslinked network of thermosets,can reduce the environmental pollution and waste of resources caused by waste of plastics,thus attracting much attention.To effectively ameliorate the environmental problems caused by the nonrecyclable of epoxy resins,a series of multi-walled carbon nanotubes(MWCNTs)/vitrimer composites(EPGCSLx)containing dual dynamic covalent bonds were prepared by introducing silicon-oxygen and disulfide bonds into the epoxy network via a one-pot method.The conductivity,thermomechanical,self-healing,reprocessing and degradability of the materials were investigated at different MWCNTs doping levels.The results show that EPGCSL5(5wt%of MWCNTs)has good electrical conductivity(2.09 S/m)and mechanical properties(tensile strength is 8.12 MPa,elongation at break is 84.67%).EPGCSL5 also possesses reprocessing,degradability,and photo-thermal properties,which fully combines the vitrimer and epoxy composites'advantages.In addition,EPGCSL5 was prepared as a human motion sensor,demonstrating its potential application as a motion sensor.