| Abstract: | 本研究主要探究的方向為二氧化矽奈米粉體對聚偏二氟乙烯（Poly(vinyld- ene fluoride）薄膜的影響，並分別針對二氧化矽粒子與有機無機混成薄膜進行探討。第一階段首先以溶膠凝膠法（Sol- Gel）製備奈米級二氧化矽粒子，以三甲基乙氧基矽烷（Trimethylethoxysilane，TMES）作為封頭劑進行表面修飾，合成出不同R值的二氧化矽溶膠後，製成具有可回溶性質的奈米粉體，如此可以改善製程中溶劑影響的問題，亦可解決大顆粒粉體因聚集而不易分散的問題。製備的過程中以FTIR鑑定反應官能基的變化；以DLS量測顆粒粒徑，並觀察奈米粉體分散於溶劑中的情形，並以TEM觀察顆粒型態；利用量測zeta potential的結果證實，二氧化矽具有帶負電的特性；然而粉體分散於特定溶劑中，其粒徑檢測的結果也有所不同。
本研究的第二階段是以利用乾式相換法製備緻密型聚偏二氟乙烯/二氧化矽（Poly(vinylidene fluoride)/Silica）混成薄膜，以UV-Vis檢測穿透度、以POM觀察結晶尺寸，其結果顯示隨著粉體添加量的增加，會提升薄膜的光穿透度，降低結晶尺寸；以XRD、DSC檢測結晶度的結果顯示，添加粉體會造成結晶度下降；薄膜的熔點不會因添加粉體而有影響，但結晶溫度則會因粉體添加越多而有下降的趨勢；測試機械性質的結果顯示，因粉體與薄膜之間無較強的鍵結，故添加越多的粉體則會造成薄膜機械性質減弱。
In this study, we focus on the effect of Poly(vinylidene fluoride) membranes with silica nano- powder, and we discuss silica particles and organic-inorganic hybrid membranes individually. First, we prepared nano-order silica particles by Sol-Gel method. Trimethylethoxysilane (TMES) is termination agent, we increased TMES to silica sol for surfaces were modified, and synthesis silica sol with different R values, and nano-powder with re-dissolved property were prepared.This achievement improves issues of solvents and particles aggregation.
In the preparation, we analysed functional groups by FTIR. The particle size, dispersion of nano-powder were measured by DLS and TEM. Silica with negative charges were verified by results of zeta potential. Powder were dispersed in specific solvents, we obtained different sizes. In this paper, preparation of densified Poly(vinylidene fluoride)/Silica hybrid by dry phase inversion in second stage.the transparency and crystal sizes measured by UV-Vis and POM. The result explains, the transparency of membranes was improved by raised powder content, but crystal sizes was reduced. The crystallinity and thermal property were determined by XRD and DSC, the result of crystallinity was redused by increased addition of powder, However, addition of powder did not influence the melt point of membranes. Via the performance of mechanical properties were measured, we could see that because bonding were not strong between powder and membranes, therefore, the performance of mechanical properties was abated with increased more powder. |
