聚丙烯腈电纺膜制备及其压电性能研究

发布时间：2018-05-08 22:24

  本文选题：聚丙烯腈 + BaTiO_3　； 参考：《天津工业大学》2017年硕士论文

【摘要】：聚丙烯腈作为一种广泛应用于过滤、吸附及复合材料等方面的聚合物,具有良好的耐气候性和耐化学试剂性。此外,其较高的偶极矩(3.5D)具备用作聚合物压电材料的潜质。因此本文选用PAN为原料并对其压电性能进行研究。本文通过静电纺丝技术,首先利用平板接收装置制备了杂乱无序的PAN和聚偏氟乙烯(PVDF)电纺膜,在同样的测试条件下对比得出了两者在输出电压、介电常数、介电损耗的优劣势。同时,通过改变PAN纺丝浓度和电纺膜热处理时间,制备了不同的PAN电纺膜样品,对其输出电压、介电常数、介电损耗、FTIR、XRD进行测试,研究了 PAN的压电性能以及构象对PAN压电性能的影响;其次,通过改变接收装置,采用辊筒接收制备了有序取向的PAN电纺膜,通过测试其输出电压、FTIR、XRD研究了辊筒转速和热处理方式对PAN构象及其压电性能的影响;最后,利用硅烷偶联剂(KH550)对钛酸钡(BaTiO_3)纳米粒子进行表面改性,将改性后的BaTiO_3与PAN混溶于DMF中,再利用平板接收装置制备了杂乱无序的PAN/BaTiO_3电纺膜。通过测试输出电压、介电常数、介电损耗、FTIR、XRD等研究了 PAN/BaTiO_3电纺膜的压电性能以及BaTiO_3纳米粒子对PAN构象的影响。(1)与PVDF电纺膜相比,PAN电纺膜的输出电压是PVDF的三分之一,介电常数是PVDF的七分之一,介电损耗却不到PVDF的二十分之一,说明PAN可弥补PVDF较高的介电损耗导致应用领域的缺憾。12wt.%的PAN电纺膜在140℃温度下松弛热处理5h具有最大的平面锯齿构象含量,其压电性能最佳。(2)通过改变辊筒转速,可制备有序取向的PAN电纺膜,且在转速为1200r/min时得到取向最好的PAN电纺膜。辊筒转速对PAN纤维的拉伸作用可促进31螺旋构象转变为平面锯齿构象,且在转速为1200r/min时得到平面锯齿构象最多的PAN电纺膜,使得其压电性能最佳。定长热处理可以在辊筒对PAN纤维拉伸作用基础上进一步对其进行拉伸,促进31螺旋构象转变为平面锯齿构象,使得定长热处理后,转速为1200r/min时PAN电纺膜压电性能更佳。而松弛热处理会促使平面锯齿构象向31螺旋构象的转变,使得其压电性能变差。(3)用硅烷偶联剂(KH550)处理后,BaTiO_3可均匀地分散在PAN纳米纤维内。与纯PAN电纺膜相比,当BaTiO_3含量为12.5%时 PAN/BaTiO_3电纺膜的输出电压提高了 300%,介电常数提高了 300%,而介电损耗却降低了67%。FTIR与XRD测试结果显示,BaTiO_3的加入可促进PAN从31螺旋构象向平面锯齿构象的转变,从而提高PAN压电性能。
[Abstract]:Polyacrylonitrile is a kind of polymer widely used in filtration, adsorption and composite materials, which has good weather resistance and chemical reagent resistance. In addition, its higher dipole moment 3.5D) has the potential to be used as a polymer piezoelectric material. Therefore, the piezoelectric properties of PAN are studied in this paper. In this paper, the disordered PAN and PVDF electrospun films were prepared by using the flat plate receiving device. Under the same test conditions, the advantages and disadvantages of the two films in the output voltage, dielectric constant and dielectric loss were obtained. At the same time, by changing the spinning concentration of PAN and the heat treatment time of electrospun film, different samples of PAN electrospun film were prepared. The output voltage, dielectric constant and dielectric loss of PAN electrospun film were measured. The piezoelectric properties of PAN and the effect of conformation on the piezoelectric properties of PAN were studied. Secondly, the ordered orientation PAN electrospun film was prepared by changing the receiving device. The effects of roll speed and heat treatment on the conformation and piezoelectric properties of PAN were studied by measuring its output voltage. Finally, the surface modification of barium titanate BaTiO3) nanoparticles was carried out by using silane coupling agent KH 550. The modified BaTiO_3 and PAN were mixed and dissolved in DMF, and then the disordered PAN/BaTiO_3 electrospun film was prepared by the flat plate receiving device. The piezoelectric properties of PAN/BaTiO_3 electrospun film and the effect of BaTiO_3 nanoparticles on the conformation of PAN were investigated by measuring the output voltage, dielectric constant, dielectric loss and the effect of BaTiO_3 nanoparticles on the conformation of PAN. The dielectric constant is 1/7 of PVDF, but the dielectric loss is less than 1/20 of PVDF. The results show that PAN can make up for the defect of PVDF due to the high dielectric loss. The 12wt.% PAN electrospun film has the largest plane sawtooth conformation content at 140 鈩，

本文编号：1863348