幾丁聚醣醋酸降解之動力學研究

Study of the Kinetics for Depolymerization of Chitosan by Using Acetic Acid

林煜登(Yu-Dung Lin)

指導教授 ： 謝國煌

國立臺灣大學/工學院/化學工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.01555

摘要

幾丁聚醣為近年來具有開發潛力的生醫材料，本實驗室目前投入幾丁聚醣分子量控制的研究，從文獻中可以發現分子量約在萬級的幾丁聚醣具有抗菌以及降解率較快等特點，故控制幾丁聚醣分子量為重要的課題，在降解幾丁聚醣的方法中，有超音波震盪法、酵素法、酸鹼法等，基於成本及量產的考量，本實驗室使用醋酸法製備較低分子量幾丁聚醣，並且以時間和醋酸的濃度為變因，去探討這些變因對幾丁聚醣分子量的影響，從結果我們可以發現在動力學的分析上，幾丁聚醣的濃度與幾丁聚醣的降解速度是呈零次關係，而醋酸的濃度如降解速率有一次關係的存在，而在溶解度方面，幾丁聚醣的分子量在十萬級以下便有不錯的水溶性，所以在作為生醫材料方法有不錯的潛力存在。

關鍵字

幾丁聚醣 ； 分子量 ； 降解 ； 醋酸

並列摘要

Chitosan is a novel medical material recently. Our lab is focus on controlling the molecular weight of chitosan. It was found that the chitosan with molecular weight at ten-thousand grades has some special characteristics, like antibiotic, faster degredational rate, etc... So it was important to control the molecular weight of chitosan. There are some methods to control the molecular weight of chitosan like supersonic waving,, enzyme methods, and acid-alkali methods, etc... In this paper, acid-handling method was chosen methods based on cost and mass-production. First we use different concentration of acetate to handle chitosan. Then we use acetone to extract the chitosan. We change the reaction time, the concentration of acetic acid, and fix other factors. Then we discuss how the time and the concentration of acetate affect the molecular weight of chitosan. From the view of kinetics, the depolymerization of chitosan is a zero-order reaction for the reactant (chitosan). The depolymerization of chitosan is a first-order reaction for the catalyst (acetic acid). TGA can prove the depolymerization of chitosan was happening and the solubility of chitosan is whole soluble for water if the molecular weight of chitosan is below 100,000.

並列關鍵字

chitosan ； molecular weight ； degradation ； depolymerization ； acetic acid

參考文獻

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