乙基纖維素稀薄溶液之本質性質

Investigation on Inherent Properties for Dilute Solutions of Ethylcellulose

賴良哲(Liang-Je Lai)

指導教授 ： 華繼中

國立中正大學/工學院/化學工程學系/碩士(2015年)

摘要

本研究利用本質黏度和動/靜態光散射系統性地探討不同分子量 (77~305kDa) 的乙基纖維素 (EC) 在三種溶劑系統 (α-Terpineol、2,2,4-Trimethyl-1,3-pentanediol emonoisobutyrate (TPIB) 和Tetrahydrofuran (THF) ) 中的本質性質。經本質黏度量測與其對應的溶液品質 (solvent qualities， ) 分析顯示出EC在三種溶劑下符合現今高分子溶液理論的良溶劑 (α>0.5)。另一方面，由光散射的結果發現EC並非以單一分子存在，而普遍在溶液中呈現極大的聚集體。這表示EC即使在極稀薄狀態，EC的本質性質亦為聚集狀態。因此EC溶液系統的本質黏度與溶液品質的物理意義仍有待釐清。

關鍵字

Mark-Houwink方程式 ； 聚集體 ； 光散射 ； 溶液品質 ； 本質黏度 ； 乙基纖維素(EC)

並列摘要

The inherent properties of ethylcellulose (EC) of varying molecular weight (77~305kDa) in three solvent systems (α-Terpineol, 2,2,4-Trimethyl-1,3-pentanediol emonoisobutyrate (TPIB), and Tetrahydrofuran (THF)) were systematically investigated using intrinsic viscosity measurement and dynamic/static light scattering. The corresponding solvent qualities ( ) retrieved from intrinsic viscosity measurement suggested that EC in all three solvent systems were in accord with good-solvent conditions according to existing theory on polymer solutions (α>0.5). In contrast, in light scattering analysis, EC revealed the prevalence of large aggregate clusters in all three solvent systems. Moreover, the results suggested that EC is inclined to form aggregates regardless of EC solutions being extremely dilute. Thus, the physical meaning of intrinsic viscosity and solvent quality in EC solution systems need to be carefully interpreted.

並列關鍵字

Aggregate ； Light scattering ； Solvent quality ； Intrinsic viscosity ； Ethylcellulose (EC) ； Mark-Houwink equation

參考文獻

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