聚苯咪唑/二甲基乙醯胺溶液及磺酸化聚苯咪唑水溶液物理性質

Physical Properties of Polybenzimidazole/N, N’-dimethylacetamide Solutions and Sulfonated Polybenzimidazole/Water Solutions

陳奕中(Yi-Chung Chen)

指導教授 ： 林秀麗

元智大學/工程學院/化學工程與材料科學學系/碩士(2006年)

摘要

本研究中，分別合成聚苯咪唑(PBI)和不同磺酸化比例之磺酸化聚苯咪唑(PBI-BS)。利用動態光散射(DLS)、動態黏彈儀(DVA)和界達電位(Zeta potential)研究PBI加入氯化鋰(LiCl)在N,N’-二甲基乙醯胺(DMAc)溶液和PBI-BS水溶液之物理性質。在動態光散射實驗中，PBI/LiCl/DMAc溶液中有兩個鬆弛形式(relaxation modes)但在PBI-BS水溶液僅存在一個鬆弛形式。快鬆弛形式(fast mode)是一種擴散的行為；而慢鬆弛形式(slow mode)代表離子的聚集。黏彈性質測試顯示PBI/LiCl/DMAc溶液中在[LiCl]/[BI]莫爾比為3.62時，角頻率為1.07 rad/sec之剪切黏度最小，在PBI/DMAc溶液中會因為加入LiCl而產生電荷遮蔽效應。在相同磺磺酸化比例下剪切黏度會隨著PBI-BS濃度增加而變大，而界達電位與濃度無關。

關鍵字

聚苯咪唑 ； 磺酸化聚苯咪唑 ； 動態光散射 ； 動態黏彈儀 ； 界達電位

並列摘要

In this study, polybenzimidazole (PBI) was synthesized from 3, 3’-diaminobenzidine and isophthalic acid. Polybenzimidazole- butanesulfonic acids (PBI-BS) with various degrees of sulfonation were prepared by sulfonating PBI with 1, 4-butanesultone (BS). The physical properties of PBI in N, N’-dimethylacetamide (DMAc) mixed LiCl and PBI-BS aqueous solutions were investigated using dynamic light scattering (DLS), dynamic viscoelasticity analyzer (DVA), and Zeta- potential. The DLS experimental results revealed two relaxation modes in PBI/LiCl/DMAc solutions, and only one mode in PBI-BS/H2O solutions. The fast mode in both two solutions was diffusion process relaxations, and the slow mode for PBI/LiC/DMAc solutions was due to the ionic aggregation. Viscoelasticity measurements showed a lowest shear viscosity for PBI/LiCl/DMAc solution at a [LiCl]/[BI] molar ratio of 3.62 (at angluar frequency ω= 1.07 rad/sec). Electrostatic screening effect occurred with presence of LiCl in PBI/DMAc solutions in Zeta potential measurements. Shear viscosity increased with raising concentration in PBI-BS aqueous solutions. Zeta potential was independent of PBI-BS concentration at fixed degree of sulfonation in PBI-BS aqueous solutions.

並列關鍵字

polybenzimidazole ； polybenzimidazole butanesulfonic acid ； dynamic light scattering ； dynamic viscoelasticity analyzer ； Zeta potential.

參考文獻

[3] 衣寶廉，燃料電池-原理與應用，五南出版社，2005.

[21] 鄭建邦，“PBI及PBI-BS合成與PBI薄膜製備”，碩士論文

[12] 程惠斌，“Nafion/甲基甲醯胺溶液之黏彈性與光散射研究”

[13] 賴楨嵐，“Nafion/二甲基甲醯胺溶液之黏彈性與光散射究”

[41] Hunter Robert J., “Foundations & Colloid Science”, Oxford 2004.