臺灣博碩士論文加值系統

本研究將聚乙烯醇（polyvinyl alcohol，PVA）的水溶液浸入凝聚槽中利用溼式相轉換法來製備親水性多孔膜。所選用的凝聚劑可分為兩種：(1) 飽和鹽類水溶液；(2) 醇類，包括甲醇、乙醇、正丙醇及正丁醇。
實驗結果顯示，以氯化鈉水溶液作為凝聚劑所製備而成的多孔膜，在乾燥時會因水與高分子界面張力的影響而收縮，導致多孔結構的破壞而成為緻密膜。此收縮現象與乾燥時膜中所含水份所造成的 Tg下降效應（Tg depression）有關，這是由於膜孔中的水對PVA具有塑化效應（plasticization），造成高分子鏈容易運動而導致的現象。要避免乾燥時的收縮，除了可利用冷凍乾燥來固化膜結構之外，亦可以利用醇類將膜孔中的水份置換出來，由於醇類是PVA的非溶劑，可以減少Tg下降的效應而固化膜結構。
研究中亦探討以醇類作為非溶劑的成膜過程，結果顯示不同碳數的醇類所製備出的膜結構也不同。藉由分析高分子和非溶劑間的親和性，並利用傅立葉轉換顯微紅外線光譜儀（FT-IR microscope）量測成膜過程中各成份的濃度變化，來探討醇類碳數對膜結構的影響。在PVA/H2O/強非溶劑的系統中，成膜時表面溶劑會快速被移除而形成高分子濃度較高的膠化層（gel layer），進而形成較緻密的表面結構。而在PVA/H2O/弱非溶劑的系統中，成膜時表面溶劑與非溶劑的質傳交換會使得非溶劑濃度提高而進入相分離區，進而形成多孔的表面結構。

Porous hydrophilic poly (vinyl alcohol) (PVA) membranes were prepared by the phase inversion method. Two kinds of coagulant were used in the present work: sodium chloride aqueous solution and alcohols, including methanol, ethanol, 1-propyl alcohol, 1-butyl alcohol.
Experimental results showed that porous membranes, using NaCl(aq) as coagulant, contracted to form dense structure at the drying stage because of Tg depression resulted from plasticization caused by the remaining water in the membrane before drying. The contraction during drying stage can be presented either by freeze drying or by replacing water with appropriate alcohols, which have lower degree of plasticization.
We have also investigated the possibility of using alcohols as coagulant because of their nonsolvency to PVA to prepared membranes. Analysis of the affinity between polymer and measurement of concentration change during membrane forming provide insight into how the porous structure was formed. For a PVA/H2O/strong nonsolvent system, the high solvent outflux resulted in a of high polymer concentration layer (gel layer), and then turned into a dense skin. On the other hand, for a PVA/H2O/weak nonsolvent system, the influx of coagulant to the cast film dominated, resulting in phase separation near the surface and a porous surface structure.

誌謝..…………………………………………..…….………… I
中文摘要..……………………………………..…….………… III
英文摘要..…………………………………….…..…………… V
目錄 ..…………………………….…………….…….……….. VII
圖索引…………………………….……………..…………….. IX
表索引………………………….……………..……………….. XI

第一章　緒論……………………………………..………... 1

第二章　文獻回顧…….……….……………….…………... 3
2.1　薄膜製備方法…………....…………………….. 3
2.2　影響成膜結構因素……………..………………. 6
2.3　成膜過程相關理論………………….………….. 7
2.3.1　熱力學.……….….…..…..…………………... 8
2.3.2　質傳動力學……….……..……..…………….. 11
2.4　PVA的性質與製膜方法..…………………..….. 14

第三章　實驗…………….………………….…………..…… 19
3.1　實驗藥品…………………….….………..…..…… 19
3.2　實驗儀器………………….….………..……..…… 20
3.3　實驗步驟………….…………………………..….. 21
3.3.1　PVA膜材製備.……….….…..…..………….. 21
3.3.2　掃描式電子顯微鏡……….…...……..……… 26
3.3.3　FTIR-microscope…………….……………….…. 26
3.3.4　霧點測試………….…...….………………… 29

第四章　結果與討論..….………………….…………..……. 31
4.1　以鹽類水溶液為凝聚劑製備薄膜…………………... 31
4.1.1　PVA/H2O/NaCl三成份相圖………...………… 31
4.1.2　PVA膜製備程序…………………….….……. 33
4.1.3　以醇類避免膜在乾燥程序中的收縮…….……. 38
4.1.4　醇類交換時間對膜結構之影響.………..… 42
4.2　以醇類為凝聚劑製備薄膜………………………….. 47
4.2.1　乾燥溫度對膜結構的影響…………..…... 47
4.2.2　不同碳數之醇類凝聚劑對薄膜結構之影響………………………….………………… 52
4.2.3　不同結構的孔洞膜形成機制……………… 58
4.2.4　以FT-IR microscope分析成膜過程中表面的濃度變化………………………………… 64

第五章 結論..….…………………….…….…………..……. 79

參考文獻..….…………………….…….………………..……. 81

1.M. Mulder, Basci Principles of Membrane Technology, Kluwer Academic Publishers (1997).
2.L. Y. Lafreniere, F. D. F. Talbot, T. Matsuura, and S. Sourirajan, “Effect of Polyvinylpyrrolidone Additive on the Performance of Polyethersulfone Ultrafiltration Membranes”, Ind. Eng. Chem. Res., 26, 2385 (1987).
3.H. A. Tsai, L. D. Li, K. R. Lee, Y. C. Wang, C. L. Li, J. Huang, and J. Y. Lai, “Effect of Surfactant Addition on Morphology and Pervaporation Performance of Asymmetric Polysulfone Membranes”, J. Membr. Sci., 176, 97 (2000).
4.I. C. Kim and K. H. Lee, “Effect of Varies Additives on Pore Size of Polysulfone Membrane by Phase-Inversion Process”, J. Appl. Polym. Sci., 89, 2562 (2003).
5.J. H. Kim and K. H. Lee, “Effect of PEG Additive on Membrane Formation by Phase Inversion”, J. Membr. Sci., 138, 153 (1998).
6.F. C. Lin, D. M. Wang, J. Y. Lai, “Asymmetric TPX Membranes with High Gas Flux”, J. Appl. Polym. Sci., 110, 25 (1996).
7.C. Stropnik, V. Musil, and M. Brumen, “Polymeric Membrane Formation by Wet-Phase Separation; Turbidity and Shrinkage Phenomena as Evidence for the Elementary Process”, Polymer, 41, 9227 (2000).
8.H. Tanaka, “Viscoelastic Phase Separation”, J. Phys.: Condens. Matter, 12, 207 (2000).
9.J. E. Mark, Polymer Data Handbook, New York: Oxford University Press (1999)
10.H. R. Allcock, F. W. Lampe, “Contemporary Polymer Chemistry”, New Jersey: Prentice Hall (1990).
11.I. Sakurada, Polyvinyl Alcohol Fibers. New York and Basel: Marcel Dekker (1985).
12.M. L. Brannon, and N. A. Peppas, “Solute Diffusion in Swollen Membranes Part VIII. Characterization of and Diffusion in Asymmetric Membranes”, J. Membr. Sci,. 32, 125-138 (1987).
13.S. G. Kim, Y. I. Kim, H. G. Yun, G. T. Lim, and K. H. Lee, “Preparation of Asymmetric PVA Membranes Using Ternary System Composed of Polymer and Cosolvent”, J. Appl. Polym. Sci., 88, 2884 (2003).
14.K. Komatsu, and O. Kusudo, “Polyvinyl Alcohol-based Hollow Fiber Membrane and Process for Producing the Same”, U.S. patent 5,976,433 (1997).
15.蔡榮進, “兩水相系統之液液相平衡熱力學模式”, 化工, 53, 2, 15 (2006).
16.T. H. Young, N. K. Yao, R. F. Chang, and L. W. Chen, “Evaluation of Asymmetric Poly(vinyl alcohol) Membranes for Use in Artificial Islets”, Biomaterials, 17, 2139 (1996).
17.W. Y. Chung, T. H. Young, and W. Y. Chiu, “The Effect of Acetic Acid on the Structure and Filtration Properties of Poly(vinyl alcohol) Membranes”, J. Membr. Sci., 172, 241 (2000).
18.W. T. Chung, T. H. Young, W. Y. Chiu, and C. Y. Lin, “The Effect of Polymeric Additives on the Structure and Permeability of Poly(vinyl alcohol) Asymmetric Membranes, Polymer, 41, 5633 (2000).
19.蔡逸文，”鹼處理對聚乙烯醇薄膜滲透蒸發效能之影響”，碩士論文，台灣大學化工系，中華民國九十三年。
20.林敬二、林宗義，儀器分析，美亞書版股份有限公司，台北 (1994)
21.R. M. Hodge, T. J. Bastow, G. H. Edward, G. P. Simon, and A. J. Hill, “Free Volume and the Mechanism of Plasticization in Water-Swollen Poly(vinyl alcohol)”, Macromolecules, 29, 8137 (1996).
22.R. M. Hodge, G. H. Edward, and G. P. Simon, “Water Absorption and States of Water in Semicrystalline Poly(vinyl alcohol) Films”, Polymer, 37, 8, 1371 (1996).
26.E. B. Bagley, T. P. Nelson, J. M. Sciglian, “3-dimesional Solubility Parameters and Their Relationship to Internal Pressure Measurement in Polar and Hydrogen Bonding Solvent”, J. Paint Technol., 43, 35 (1971).
27.F. E. Eichie, R. S. Okor, R. Groning, “Application of Solubility Parameters to the Formulation of Acrylate Methacrylate Film Coating System”, J. Appl. Polym. Sci., 87, 1339 (2003).
28.A. F. M. Barton, CRC Handbook of Solubility Parameters and Other Cohesion Parameters, Florida: CRC Press, Inc. (1988).
29.J.H. Hildebrand, J.M. Prausnitz and R.L. Scott, Regular and related solutions : the solubility of gases, liquids, and solids, New York : Van Nostrand Reinhold Co. (1970).
30.T. H. Young and L. W. Chen, “A Two Step Mechanism of Diffusion-Controlled Ethylene Vinyl Alcohol Membrane Formation”, J. Membr. Sci., 57, 69 (1991).
31.L. W. Chen and T. H. Young, “Effect of Nonsolvent on the Mechanism of Wet-Casting Membrane Formation from EVAL copolymers”, J. Membr. Sci., 59, 15 (1991).
32.G. Socrates, Infrared Characteristic Group Frequencies, Chichester: John Wiley & Sons (1998).
33M. G. Cascone, L. Lazzeri, E. Sparvoli, M. Scatena, L. P. Serino and S. Danti, “Morphological Evaluation of Bioartificial Hydrogels as Potential Tissue Engineering”, J. Mater. Sci. Mater. Med., 15, 1309 (2004).
34C. Weis, E. K. Odermatt, J. Kresser, Z. Funke, T. Wehner and D. Freytag, “Poly(vinyl alcohol) Membranes for Adhesion Prevention”, J. Biomed. Materi. Res. Part B-Applied Biomaterials, 70B, 2, 191 (2004).
35A. J. Reuverse, F. W. Altena and C. A. Smolders, “Demixing and Gelation Behavior of Ternary Cellulose Acetate Solution”, J. Polym. Sci. Polym. Phys., 24, 793 (1986).
36X. F. Wang, D. F. Fang, K. Yoon, B.S. Hsiao and B. Chu, “High Performance Ultrafiltration Composite Membranes Based on Poly(vinyl alcohol) Hydrogel Coating on Crosslinked Nanofibrous Poly(vinyl alcohol) Scaffold”, J. Membr. Sci., 278, 1-2, 261 (2006).
37I. C. Kim and K. H. Lee, “Dyeing Process Wastewater Treatment Using Fouling Resistant Nanofiltration and Reverse Osmosis Membranes”, Desalination, 192, 1-3, 246 (2006).
38X. F. Wang, X. M. Chen, K. Yoon, D. F. Fang, B.S. Hsiao and B. Chu, “High Flux Filtration Medium Based on Nanofibrous Substrate with Hydrophilic Nanocomposite Coating”, Environ. Sci. Technol. 39, 19, 7684 (2005).