在本研究中，我們探討了透過摻入BaTiO3奈米棒以增強聚偏氟乙烯（PVDF）膜複合材料的特性，採用相轉化技術進行最佳化，並以退火作為後期處理。將直徑介於80至150微米的BaTiO3（BT）奈米棒按不同體積分數（10%、20%、30%、40%）添加至聚合物基材中。透過掃描式電子顯微鏡（SEM）觀察到淬火相轉化導致了形態上產生變化，如孔隙的形成或聚合物基材結構的改變。相轉化與退火技術的結合使純PVDF中的β相增加，並且過程中在膜內形成更多孔隙，而此種現象則與退火過程相關。然而當陶瓷顆粒佔據可用空間時，造成β相的含量從82.67%逐漸降低至63.65%，此一現象透過傅立葉變換紅外光譜（FTIR）分析和X射線繞射（XRD）得到驗證。
PVDF/BT複合膜的相態行為經過差示掃描量熱法（DSC）的熱分析後，可觀察到隨著BT含量的增加而產生了顯著變化。當BT奈米棒含量增加時，結晶發生的溫度從165.95°C下降至164.33°C。此外，PVDF的玻璃轉變溫度從初始的36°C大幅上升至109°C，隨著BT奈米棒含量的增加，對複合材料的溫度特性方面產生重大影響。因此了解熱行為及其對充電動力學的影響，對於在能源收集應用中提高複合材料效率至關重要。
透過自製的螺線管設備和數位示波器進行的輸出電壓反應評估了該材料在機械力作用下的壓電潛能。令人注目的是，儘管含有30wt% BT棒的複合材料的β相有所降低，但其展現出最大的輸出電壓，達到7.11伏。這是由於BT奈米棒在材料系統中的產生了主導作用。根據拉伸測試的結果顯示，當添加BT奈米棒時，PVDF複合材料的拉伸強度最高達到42.29 Mpa並且伸長率降低，該聚合物的機械性質得到顯著增強。
總結而言，本研究著重於PVDF/BT複合物的結合，深入探究了調整不同參數之間的相互作用，尤其是不同濃度的BT奈米棒添加物對複合材料的影響。研究結果顯示對於優化PVDF/BT複合膜以提升性能具有重要意義，這些發現對於從薄膜技術到先進材料科學的多元應用領域均具有廣泛的影響。

This work examines the enhanced polyvinylidene fluoride membrane composite properties through BaTiO3 nanorod and nanopowder incorporation. The investigation utilizes a phase inversion technique to optimize, with heat treatment as a post-treatment. BaTiO3 (BT) nanorod, with an average diameter ranging from 80 to 150 µm and nm respectively, were added to the polymer matrix at different weight total (10%, 20%, 30%, and 40%). Phase inversion that follows the quenching results in morphological changes, such as the formation of pores or changes in the polymer matrix structure; this formation is observed using a Scanning Electron Microscopy (SEM). The phase inversion and queenching technique combined increased the β phase in the pure PVDF. The phenomenon is related to the annealing process, which creates more pores inside the membrane. The β phase gradually decreases from 82.67% to 63.65% for nanorod. This phenomenon is validated with Fourier Fourier-transformed infrared Spectroscopy (FTIR) analysis and X-ray Diffraction (XRD).
The phase behaviour of the PVDF/BT composite membrane shows notable alterations, with increased BT as shown by Thermal investigation using Differential Scanning Calorimetry (DSC). An observable decrease in the temperature at which crystallization occurs, from 165.95 to 164.33 °C, was noticed as BT nanorods increased. Furthermore, the glass transition temperature of PVDF, which was initially 36°C, significantly increased to 109°C as the amount of BT nanorods increased, indicating significant changes in the thermal characteristics of the composite. Understanding the thermal behaviour and its implications on the charging kinetics is essential for maximizing the efficiency of the composite in energy harvesting applications.
Output voltage response tests conducted using a custom-made solenoid setup and a digital oscilloscope revealed the material's piezoelectric potential under mechanical force application. Surprisingly, the composite with 30wt% BT rods displayed the most significant output voltage, reaching 7.11 V even though the β phase decreased. However, it happened because of a BT nanorod takeover in the material system. However, based on the tensile test, it is evident that the characteristics of the PVDF composite change improvements when BT nanorods are added. The polymer demonstrated enhanced stiffness, as evidenced by its improved tensile strength, reaching a maximum of 42.29 Mpa, and reduced strain.
In conclusion, this work examines the incorporation of PVDF/BT composite, elucidating to comprehensively understand the interplay of variables, particularly the impact of varying concentrations of BT nanorod filler. The findings are expected to contribute valuable insights into optimizing PVDF/BT composite membranes for enhanced performance, with implications for diverse applications ranging from membrane technologies to advanced materials science.

Keyword: Phase Inversion, Electrospinning, BaTiO3, Nanorod, Nanoparticle

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