以即時X光散射鑑定電紡製程之聚(偏氟乙烯-三氟乙烯)之變形機制以及壓電性質

Using in-situ X-ray Scattering to Identify the Deformation Mechanism and Piezoelectric Properties of Poly(vinylidene fluoride-trifluoroethylene) by Electrospinning

王盈之(Ying-Jhih Wang)

指導教授 ： 黃爾文

國立交通大學/工學院/材料科學與工程系所/碩士(2018年)

摘要

近年來，壓電材料被廣泛地運用在微電子智慧元件中(如: 生物感測器、穿戴式電子設備)。雖然傳統的壓電材料(如: 石英、陶瓷(鋯鈦酸鉛PbTiO3)
等材料)，有著非常高的壓電性能，但是若要將他們應用在可撓式的電子設備裡，其缺乏延展性的劣勢會導致無法應用於可撓式穿戴需求，故利用電紡製程之PVDF(聚偏氟乙烯)材料被引進壓電領域中。PVDF擁有至少四種不同的結晶相，其中發現β相因為其分子排列結構為(TTTT)(全反式)，這種排列一致的結構使其內部電偶極都從氟原子指向氫原子，累積的淨電偶極使之具有極性，故具有壓電性。而P(VDF-TrFE)聚(偏氟乙烯-三氟乙烯)是PVDF與TrFE (三氟乙烯)的共聚物，本實驗透過電紡(Electrospinning)製程，且引入退火熱處理使P(VDF-TrFE)的β相增加進而提升壓電性，探討經處理後此材料的機械性質變化。另外透過量測壓電電荷常數(d33)，發現不同階段的應變量會造成d33值有所差異，因此使用即時性的SAXS (Small-angle X-ray scattering)和WAXS (Wide-angle X-ray scattering)拉伸實驗結合顯微技術觀測影像，分別利用Origin和Powder Cell繞射峰多峰擬合(Multi peak retvield)的功能，取得材料晶格結構、微結構資訊等，研析在不同應變時內部變形機制和對壓電訊號之貢獻，目標能透過調整退火的參數達到最佳化應用於人體生理監控的應用例如：脈搏、心跳、血壓等，期望可提供更舒適與高感度生理感。

關鍵字

高分子壓電 ； 機械性質 ； 感測器 ； 電紡製程 ； 聚(偏氟乙烯-三氟乙烯)

並列摘要

The use of piezoelectric polymer films and layers for sensing and ultrasonic transduction purposes has been known for several decades. Semi-crystalline polymer, poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] copolymer is a high mechanical flexibility piezoelectric material and availability in large areas that would be difficult to achieve by conventional materials. Using the electrospinning method and controlling the parameters such as annealing temperature and molecular chain orientation to design smart skin. This study investigated the mechanical and piezoelectric properties of P(VDF-TrFE) by in-situ X-ray diffraction experiment, d33 meter. We express the deformation in terms of three mechanisms of microstructure activity in P(VDF-TrFE) under tensile loading. The second stage of deformation mainly affects the piezoelectric properties, that is the lamella structure region in the microstructure. It can be deformed into the second stage by using post-treatment in this study for P(VDF-TrFE)-based sensor which is thin and relatively sensitive piezoelectric properties.

並列關鍵字

polymer piezoelectricity ； mechanical properties ； sensor ； electrospinning ； P(VDF-TrFE)

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