碳纳米管分散强化PVDF复合薄膜导热性能探究

采用多巴胺（DA）和3?氨基丙基?三甲氧基硅烷（APTMS）对碳纳米管（CNTs）进行DA辅助共修饰，并用溶剂浇铸法制备具有优异热性能和力学性能的聚偏氟乙烯（PVDF）复合薄膜；采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、差示扫描量热仪（DSC）、X射线光电子能谱仪（XPS）、热常数分析仪和电子单纱强力仪等对材料的微观形貌、结晶度、导热性能和力学性能进行了表征。结果表明，经DA和APTMS共修饰后的PDA?CNTs?NH₂具有良好的分散性能；PDA?CNTs?NH₂的加入，有利于改善PVDF复合薄膜的热稳定性；与纯PVDF薄膜和PVDF/CNTs复合薄膜相比，PVDF/PDA?CNTs?NH₂复合薄膜的导热性能和力学性能显著增强，在8 %（质量分数，下同） PDA?CNTs?NH₂的填料负载下，其热导率达到0.337 9 W/（m·K），是纯PVDF薄膜的1.78倍，其拉伸强度为52.67 MPa，是纯PVDF复合薄膜的1.36倍。

Study on Thermal Conductivity of Carbon Nanotube Dispersion Strengthened PVDF Composite Film

Carbon nanotubes （CNTs） were modified with dopamine （DA） and 3?aminopropyl?trimethoxysilane （APTMS），and then a solvent casting method was used to prepare poly（vinylidene fluoride） （PVDF） composite films with excellent thermomechanical properties. The microscopic morphology， crystallinity， thermal properties and mechanical properties were characterized by means of scanning electron microscope， transmission electron microscope， differential scanning calorimeter， X?ray photoelectron spectrometer， thermal constant analyzer， and electronic single yarn strength meter. The results indicated that the DA?APTMS?co?decorated CNTs （PDA?CNTs?NH₂） exhibited good dispersion properties. The addition of PDA?CNTs?NH₂ was benefical to improve the thermal stability of PVDF composite films. The thermal conductivity and mechanical properties of the PVDF/PDA?CNTs?NH₂ composite films were significantly enhanced compared to the pure PVDF and PVDF/CNTs composite films. Under a loading of 8 wt.% PDA?CNTs?NH₂ filler， the composite films achieved a thermal conductivity of 0.337 9 W/（m·K） and tensile strength of 52.67 MPa， increasing by 78 % and 36 % compared to pure PVDF film， respectively.