製備PVDF接枝丙烯酸二氧化鈦薄膜

self-assembly of TiO2 on PVDF membrane grafted with acrylic acid

呂紹仲(Shao-Chung Lu)

指導教授 ： 游勝傑

中原大學/工學院/土木工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200091

摘要

由於薄膜操作時常有薄膜阻塞而導致通量下降之問題，因此本研究以電漿進行薄膜表面之聚合作用，使PVDF(polyvinylidene fluoride)高分子薄膜表面具有羧基之功能性基團，再進行表面二氧化鈦之塗佈，使二氧化鈦因自聚作用與表面粗糙度塗佈於薄膜表面上，以增加改質PVDF薄膜之親水性，進而提高薄膜通量，並擁有光催化作用並得到自淨作用的特性，以降低薄膜積垢物的現象。本研究針對PVDF薄膜進行改質，使用氬氣與氧氣使薄膜表面產生羧基之功能性基團，並改變不同操作電壓與時間，以尋找電漿最佳化操作參數，再藉由改變丙烯酸聚合條件，找出最佳聚合參數，最後塗佈不同含量之二氧化鈦，並進行模廠測試，以模擬薄膜實際操作過濾時之情況。其結果顯示，經由改質PVDF高分子薄膜由於親水性大幅提升，由116.4°轉為23.0°，使薄膜通量之提升並獲得減緩積垢之特性，在結果中發現過多的二氧化鈦添加會使得薄膜表面孔洞造成阻塞之現象，而降低薄膜通量及提高透膜壓力，發現有改質之TiO2薄膜具有較高的薄膜通量與良好的通量回復率，UV累積照射時間之通量提升達107%。

關鍵字

二氧化鈦 ； 光催化作用 ； 電漿 ； 自淨作用 ； 牛血清蛋白 ； PVDF高分子薄膜

並列摘要

In this study, poly(vinylidene fluoride) (PVDF) membrane was decorated with carboxylic acid groups by plasma-induced graft polymerization of acrylic acid and then coated with titanium(IV) oxide nanoparticles by self-assembly method in order to activate its surface with photocatalytic, bactericidal, self-cleaning, and anti-fouling properties. The plasma treatment parameters (RF power=75 to 125 W, plasma exposure time=60 to180 seconds) and acrylic acid grafting conditions (monomer concentration=40% to 80%, temperature=30 to 70oC, reaction time=0.5 to 6 hours) were optimized to produce the highest degree of grafting. Various TiO2 loadings (0.5, 1.5, and 3.0 wt%) were also tested. The modification procedure successfully reduced the contact angle of PVDF membrane from 116.4o to 23.0o, which led to higher flux and slower fouling. Flux recovery rate as high as 107% was achieved after UV exposure. However, excessive TiO2 loading caused pore blockage and degradation of flux.

並列關鍵字

PVDF membrane ； Plasma ； TiO2 ； Photocatalytic ； Self-cleaning ； BSA

參考文獻

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