教師資料查詢 | 類別: 期刊論文 | 教師: 董崇民 Don, Trong-ming (瀏覽個人網頁)

標題:Free rradical degradation of chitosan with potassium persulfate
學年90
學期1
出版(發表)日期2002/01/01
作品名稱Free rradical degradation of chitosan with potassium persulfate
作品名稱(其他語言)
著者董崇民; Don, Trong-ming; Hsu, Shih-chang; Chiu, Wen-yen
單位淡江大學化學工程與材料工程學系
出版者
著錄名稱、卷期、頁數Polymer degradation and stability 75(1), pp.73-83
摘要A thermal dissociation initiator, potassium persulfate (KPS), is added to the chitosan solution at 70 °C; immediately, the solution viscosity and the molecular weight of chitosan decrease in a very short time. Size exclusion chromatography, nuclear magnetic resonance and electron spin resonance were used to study the degradation mechanism. A free radical degradation mechanism of chitosan by KPS is then proposed. When KPS is thermally dissociated into anionic radicals, they are attracted to the cationic amino group in the chitosan ring. Subsequently, the anionic radical attacks the C-4 carbon and transfers the radical to the C-4 carbon by subtracting the hydrogen from it. The presence of free radical at C-4 carbon eventually results in the breakage of the glycosidic C–O–C bond in the chitosan main chain. According to this mechanism, the concentrations of KPS, total free radicals and the degraded chitosan chain at different degradation times are all calculated by solving the rate equations. Finally, the calculated average molecular weights of the degraded chitosan chains at different reaction times agree with the experimental values.
關鍵字Chitosan;Potassium persulfate;Free radical;Degradation
語言英文
ISSN0141-3910;1873-2321
期刊性質國外
收錄於
產學合作
通訊作者
審稿制度
國別英國
公開徵稿
出版型式,電子版,紙本
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