Liu Y Z, Zhang H, Yu J X, Huang Z Y, Wang C, Sun Y
Department of Astronautic Science and Mechanics, Harbin Institute of Technology Harbin China
School of Chemistry and Chemical Engineering, Harbin Institute of Technology Harbin China.
RSC Adv. 2020 May 5;10(29):17377-17386. doi: 10.1039/d0ra01769h. eCollection 2020 Apr 29.
Poly(vinylidene difluoride) (PVDF) and its copolymers as the polymers with the highest piezoelectric coefficient have been widely used as sensors and generators. However, their relatively low performances limit their applications in some harsh environments. In this work, piezoelectric poly(vinylidene-trifluoroethylene) P(VDF-TrFE) matrices with different amounts of polyhedral oligomeric silsesquioxane (POSS) were prepared by a low temperature solvent evaporation method and thermal poling. The morphology, surface performance, crystalline phase, and piezoelectric and ferroelectric properties of the nanocomposites were investigated and the influence of POSS on these performances was studied. POSS had good compatibility with P(VDF-TrFE) and did not affect the crystalline phase formation of the matrix. The composites presented good piezoelectric properties. Piezo- and triboelectric nanogenerators were designed and fabricated. The voltage and current outputs were analyzed and the polarization effect was evaluated. The average output voltage and the current density of the matrix were 3 V and 0.5 μA cm when subjected to a force of 38 N on an area of 1 cm. The mechanical properties of P(VDF-TrFE)/POSS nanocomposites were also studied by the nanoindentation test. The hardness and modulus of samples increased 20% and 17% with a low addition of POSS. Atomic oxygen erosion properties of the composites were numerically simulated by the Monte Carlo method. The erosion cavity shape and depth were compared and studied. The influence of POSS addition on the P(VDF-TrFE) matrix and the associated reinforcing mechanism were analyzed.
聚偏氟乙烯（PVDF）及其共聚物作为具有最高压电系数的聚合物，已被广泛用作传感器和发电机。然而，它们相对较低的性能限制了其在一些恶劣环境中的应用。在这项工作中，通过低温溶剂蒸发法和热极化制备了具有不同含量多面体低聚倍半硅氧烷（POSS）的压电聚（偏氟乙烯-三氟乙烯）P（VDF-TrFE）基体。研究了纳米复合材料的形态、表面性能、晶相以及压电和铁电性能，并研究了POSS对这些性能的影响。POSS与P（VDF-TrFE）具有良好的相容性，且不影响基体的晶相形成。复合材料呈现出良好的压电性能。设计并制备了压电和摩擦电纳米发电机。分析了电压和电流输出，并评估了极化效应。当在1平方厘米的面积上施加38牛的力时，基体的平均输出电压和电流密度分别为3伏和0.5微安/平方厘米。还通过纳米压痕试验研究了P（VDF-TrFE）/POSS纳米复合材料的力学性能。在低添加量的POSS情况下，样品的硬度和模量分别提高了20%和17%。通过蒙特卡罗方法对复合材料的原子氧侵蚀性能进行了数值模拟。比较并研究了侵蚀腔的形状和深度。分析了POSS添加对P（VDF-TrFE）基体的影响及其相关的增强机制。
