Chamakh Mariem M, Mrlík Miroslav, Leadenham Stephen, Bažant Pavel, Osička Josef, AlMaadeed Mariam Al Ali, Erturk Alper, Kuřitka Ivo
Center for Advanced Materials, Qatar University, Doha 2713, Qatar.
Centre of Polymer Systems, Tomas Bata University in Zlin, Trida T. Bati 5678, 760 01 Zlin, Czech Republic.
Nanomaterials (Basel). 2020 Nov 26;10(12):2345. doi: 10.3390/nano10122345.
This study deals with the effect of zinc oxide (ZnO) star-like filler addition to the poly(vinylidene fluoride) (PVDF) matrix, and its effect on the structural and physical properties and consequences to the vibration sensing performance. Microwave-assisted synthesis in open vessel setup was optimized for the preparation of the star-like shape of ZnO crystalline particles. The crystalline and star-like structure was confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDX). Furthermore, the PVDF-based composites were prepared using a spin-coating technique from solution. An investigation of the transformation of the crystalline phase to the crystalline phase of the neat PVDF matrix and with various filler concentrations was performed using Fourier-Transform infrared (FTIR) spectroscopy, which shows an enhanced -phase from 44.1% to 66.4% for neat PVDF and PVDF with 10 wt.% of particles, respectively. Differential scanning calorimetry (DSC) measurements and investigation showed enhanced crystallinity and melting enthalpy of the composite systems in comparison to neat PVDF, since ZnO star-like particles act as nucleating agents. The impact of the filler content on the physical properties, such as thermal and dynamic mechanical properties, which are critical for the intended applications, were investigated as well, and showed that fabricated composites exhibit enhanced thermal stability. Because of its dynamic mechanical properties, the composites can still be utilized as flexible sensors. Finally, the vibration sensing capability was systematically investigated, and it was shown that the addition of ZnO star-like filler enhanced the value of the thickness mode piezoelectric constant from 16.3 pC/N to 29.2 pC/N for neat PVDF and PVDF with 10 wt.% of ZnO star-like particles.
本研究探讨了向聚偏二氟乙烯（PVDF）基体中添加氧化锌（ZnO）星状填料的效果，及其对结构和物理性能的影响以及对振动传感性能的影响。在敞口容器装置中对微波辅助合成进行了优化，以制备星状的ZnO晶体颗粒。通过X射线衍射（XRD）、扫描电子显微镜（SEM）和能量色散光谱（EDX）确认了晶体和星状结构。此外，采用溶液旋涂技术制备了基于PVDF的复合材料。使用傅里叶变换红外（FTIR）光谱对纯PVDF基体以及不同填料浓度下从晶相到晶相的转变进行了研究，结果表明，纯PVDF和含10 wt.%颗粒的PVDF的β相分别从44.1%提高到66.4%。差示扫描量热法（DSC）测量和研究表明，与纯PVDF相比，复合体系的结晶度和熔化焓有所提高，因为ZnO星状颗粒起到了成核剂的作用。还研究了填料含量对物理性能（如热性能和动态力学性能）的影响，这些性能对于预期应用至关重要，结果表明制备的复合材料具有增强的热稳定性。由于其动态力学性能，该复合材料仍可作为柔性传感器使用。最后，系统地研究了振动传感能力，结果表明，对于纯PVDF和含10 wt.% ZnO星状颗粒的PVDF，添加ZnO星状填料使厚度模式压电常数的值从16.3 pC/N提高到29.2 pC/N。
