以原玉米淀粉为原料，在醇相中制备了高取代度羧甲基淀粉，采用红外光谱仪、扫描电镜、X 射线衍射仪、DV-I Prime 旋转黏度仪和紫外分光光度计对其理化性质进行了测定和分析，并与原玉米淀粉进行比较． 结果表明: 原玉米淀粉分子上成功接入了羧甲基官能团，而且取代度大于1. 0; 羧甲基淀粉颗粒发生膨胀，裂纹明显，表面粗糙，颗粒中心出现大的爆裂孔; 羧甲基淀粉的结晶结构被破坏，甚至结晶区消失; 羧甲基淀粉透明度和冻融稳定性远远优于原玉米淀粉，而且取代度越高透光率和冻融稳定性越好．

Firstly,carboxymethyl starches ( CMS) with high degree of substitution ( DS) were prepared from native corn starch via a reaction in aqueous alcohol.Secondly,the physicochemical properties of the prepared starches were measured and analyzed by means of FT-IR,SEM,XRD,DV-I Prime rotary viscometry and ultraviolet spectrophotometry,which were then compared with those of native corn starch.The results indicate that ( 1) after the reaction,native corn starch is successfully carboxymethylated with a DS of more than 1. 0,and starch granules are rough,swollen and cracked,with huge burst holes in the their center; ( 2) the crystalline sharp peaks of CMS damage and even disappear after the carboxymethylation; and ( 3) in comparison with native corn starch,CMS possesses much better transparency and freeze-thaw stability that are both positively related to DS.