以溶膠凝膠、溶液分散及熔融插層方式製備 有機/無機奈米複合材料及其性質之研究

Synthesis and Properties of Organic-Inorganic Nanocomposite Materials Prepared by Sol-Gel, Solution Dispersion and Melt Intercalation Approaches

陳啟倫(Chi-Lun Chen)

指導教授 ： 葉瑞銘

中原大學/理學院/化學研究所/博士(2005年)

https://doi.org/10.6840/cycu200500633

摘要

本論文是以不同的合成技術與材料，製備一系列的有機∕無機混成材料（高分子奈米複合材料），進行結構、性質的分析。 本研究主要分為三個部份：

第一部份，是利用3-(Trimethoxysilyl)propylmethacrylate (MSMA)當作導電高分子 — 聚乙烯咔唑（Poly(vinylcarbazole)）與四乙氧基矽烷（Tetraethoxysilane, TEOS）間的偶合劑，以「溶膠凝膠法」製備聚乙烯咔唑∕二氧化矽奈米複合材料。 若將導電高分子塗佈在鐵片上，會促使表面形成惰性金屬氧化物保護層，避免或延緩鐵片繼續腐蝕，而TEOS的導入，一方面加強與鐵片的表面形成Si-O-Fe之共價鍵結，可有效提升導電高分子附著於鐵片的能力，藉此增加塗層防蝕時效性；另一方面，溶膠-凝膠反應所形成矽氧無機網狀結構的疏水性，使水分子不易滲入塗層，且增加水氣的穿透路徑，可延遲水氣附著於鐵片上，達到防蝕效果。 本實驗結合上述四種防蝕機制，以不同比例之MSMA與聚乙烯咔唑形成共聚物後，再與TEOS進行溶膠-凝膠反應，製備出聚乙烯咔唑∕二氧化矽奈米複合材料。 研究中以反射式紅外線光譜儀佐證Si-O-Fe共價鍵的產生，百格測試證實塗層在此鐵片上附著性的提升，水滴接觸角的增加證實了矽氧無機網狀結構對塗層疏水性的強化，最後再利用電化學的防腐蝕測試證明SiO2的導入，能有效提升塗層材料的抗腐蝕性能。

第二部份，是以「溶液分散法」製備可溶性聚醯亞胺∕黏土奈米複合材料。 本研究為增加聚醯亞胺的加工性，以立體障礙結構較大的1,4-Bis(4-aminophenoxy)-2-tert-butylbenzene (BATB) 以及2,2-Bis[4-(dicarboxyphenoxy)phenyl]propane dianhydride (BSAA) 為單體，以化學醯亞胺化來合成可溶性聚醯亞胺（SPI），而後再利用「溶液分散法」將親油性改質黏土均勻分散在其中，製備出可溶性聚醯亞胺∕黏土奈米複合材料。 再藉由電化學腐蝕測試發現，隨黏土含量的增加，金屬的耐腐蝕性有明顯的提升。 而其他熱性質、機械性質、阻隔性質等特性，亦隨黏土含量的增加，而有明顯增強、變好的趨勢。

第三部份，是利用「熔融插層法」來製備聚碳酸酯∕黏土複合材料，其過程中不需要溶劑，可減少環境的污染，且製程設備可直接套用於生產線，是未來高分子奈米複材商品化時最有可能使用的方法。 本研究以商業考量，選用五大泛用工程塑膠裡最具發展潛力的聚碳酸酯，以及方便、便宜可購得之商業用親油性改質黏土為原物料，經雙螺桿押出機混摻造粒後，以射出成型機射出啞鈴型拉力試片，再以此試片進行一連串的性質試驗分析。 而聚碳酸酯∕黏土複合材料的機械性質、難燃等性質，都明顯較聚碳酸酯來得優異，此外該奈米複合材料的熱傳導性質的探討，也是本研究的另一重點。

關鍵字

溶膠凝膠法 ； 溶液分散法 ； 熔融插層法 ； 黏土 ； 奈米複合材料

並列摘要

In this research, we prepared three kinds of organic-inorganic hybrid materials (polymer nanocomposites) by different nano-technologies and materials. This essay is divided into three parts.

In the first part, 3-(trimethoxysilyl)propylmethacrylate (MSMA) was employed as a coupling agent to connect organic poly(vinylcarbazole) and inorganic TEOS to prepare a series organic-inorganic hybrid materials by sol-gel approach. It found to protect steel from corrosion as a result of four mechanisms：1. conductive polymers induce the inertly oxidative layer to avoid corrosion, 2. the covalent bond — Fe-O-Si configurating enhances adhesive ability of conductive polymers on steel, 3. the ≣Si-O-Si≣ structure is hydrophobic and prevents moistures from interpenetrating. 4. barrier property of the silicate SiO2 nanoparticles dispersing in a polymer matrix to increase the tortousity of the diffusion pathway of oxygen and water. Thus, this research proves the covalent bond — Fe-O-Si by ATR-FTIR spectroscopy, the adhesive ability by Scotch Tape Test and the hydrophobicity of ≣Si-O-Si≣ structure was proven by water contact angle and moisture absorption test. Finally, it found that the enhancement of anticorrosive ability due to ≣Si-O-Si≣ network inducting conductive polymers by electrochemical voltammetric test.

The second part, a series of polymer-clay nanocomposite (PCN) materials that consisted of soluble polyimide (SPI) and layered montmorillonite (MMT) clay are successfully prepared by the solution dispersing technique. SPI is first prepared by chemical imidization and followed by solution dispersing the clay platelets into the SPI matrix. PCN materials, in the form of coating, incorporating with low clay loading on cold-rolled steel (CRS) are found much superior in anticorrosion performance over those of bulk SPI on the basis of a series of electrochemical measurement of corrosion potential, polarization resistance, corrosion current and impedance spectroscopy in 5 wt% NaCl(aq) electrolyte. Effects of the material composition on the O2/H2O molecular permeability, optical clarity, thermal stability and mechanical strength of SPI along with PCN materials, in the form of membrane, were studied by molecular permeability analysis (GPA), ultraviolet-visible transmission spectra, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA), respectively.

The third part is concerned with the relative to the bulk polymer preparation and properties of polycarbonate/clay nanocomposite materials. We used polycarbonate (CHIMEI-ASAHI PC-110) and commercial organoclay (SCP Cloisite® 30B) to prepare PC/clay nanocomposites by melt intercalation through the twin-roller mixer. The as-prepared materials in the form of pellet were then shaped by injection-molding machine and the as-molded specimens were subsequently examined by chemical characterizations through powder X-Ray diffraction (XRD) and transmission electron microscopy (TEM). Effect of the organoclay on thermal stability, mechanical strength and surface wettability of PCN materials, in both the form of standard dumbbell shape and pellet, was studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), tensile test, hardness test and contact-angle measurements, respectively. The properties of PC/clay nanocomposite materials also exhibited much better performance than that of neat polymer.

並列關鍵字

Clay ； Solution dispersion ； Melt intercalation ； Nanocomposite ； Sol-Gel

參考文獻

42. 孫澄源, “陶瓷製造技術”, 中華民國陶業研究學會, 1992.

46. K. H. Wang, M. H. Choi, C. M. Koo, Y. S. Choi, I. J. Chung, Polymer, 2001, 42, 9819.

55. J. J. Lin, I. J. Cheng, R. Wang, R. J. Lee, Macromolecules, 2001, 34, 8832.

38. H. R. Dennis, D. L. Hunter, D. Chang, S. Kim, J. L. White, J. W. Cho, D. R. Paul, Polymer, 2001, 42, 9513.

27. A. G. MacDiamid, L. S. Yang, W. S. Huang, B. D. Humphrey, Synth. Met., 1987, 18, 393.