不同浓度下乙醇-水溶液的缔合状态  

Association State in Ethanol-Water Solution with Different Ethanol Concentration

作　　者：曾新安[1] 杨星[1] 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2010年第12期120-123,共4页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(21076088);广东省自然科学基金资助项目(9151008901000159)

摘　　要：为了研究不同浓度的乙醇-水溶液的缔合状态,采用1HNMR对其氢键缔合展开分析.发现:溶液中弱氢键C H…O随浓度变化的幅度较小,其中CH2比CH3更易形成弱氢键,也更易受浓度波动的影响;至于强氢键O H…C,乙醇分子OH比水分子更易受浓度变化的影响,溶液在乙醇摩尔分数x=0.550时出现最强的氢键缔合网络结构.根据缔合强度大小把溶液浓度范围大致分为3个区间:0<x<0.236时,水分子缔合结构占主要地位;0.236≤x≤0.735时,乙醇分子和水分子相互作用,形成更强、更广的氢键缔合网络结构;0.735<x<1.000时,乙醇分子缔合结构占据主要地位.This paper deals with the interaction between hydrogen bond association and ethanol content in ethanol-water solution by means of 1H NMR.The results show that（1）the weak hydrogen bond CH…O slightly changes with ethanol concentration;（2）CH2 is easier to form weak hydrogen bond and is more sensitive to ethanol concentration than—CH3;and（3） as for the strong hydrogen bond OH…O,OH groups in ethanol molecule are more sensitive to the concentration than water,and the strongest hydrogen bond association occurs at a mole fraction of ethanol（x） of 0.550.Furthermore,according to the association strength of hydrogen bond,the ethanol concentration can be approximately divided into three regions,namely,0x0.236,0.236≤x≤0.735 and 0.735x1.000.In the first region,there is a leading association in water molecule,while in the third region,there is a leading association in ethanol molecule,and,in the second region,the strongest and the widest hydrogen bond association net is formed by the interaction of ethanol and water molecules.

关 键 词：乙醇-水溶液 氢键缔合 乙醇浓度 氢核磁共振谱 

分 类 号：TS261.2[轻工技术与工程—发酵工程] O645.11[轻工技术与工程—食品科学与工程]