摘要
用光度滴定法测定了羧甲基菊粉的取代度。采用0.8×10-3mol/L的CuSO4溶液滴定0.5 g/L的羧甲基菊粉钠溶液,在241 nm处检测滴定过程中溶液吸光度的变化。当溶液吸光度趋于恒定时,羧甲基菊粉钠已完全与Cu2+螯合。由消耗CuSO4溶液的体积确定羧甲基的含量,进而求得在m(菊粉)∶m(氯乙酸)=1∶1.1、1∶1.6、1∶2.2时制得的3种不同羧甲基菊粉的取代度分别为0.34、0.43和0.48。
Degree of substitution （DS） of carboxymethylinulin was analysed by spectrophotometric titration. When the solution of sodium salt of carboxymethylinulin（0. 5 g/L） is titrated with the solution of CuSO4（0. 8 × 10^-3 mol/L）,the chelate of carboxymethylinulin and Cu^2＋ is formed which has the maximum absorbance at 241 nm. The absorbance remains unchanged when the sodium salt of carboxymethylinulin was chelated by Cu^2＋ completely. Then, the content of carboxymethyl group can be obtained by the consumed volume of CuSO4 and the DS of carboxymethylinulin can be calculated. DS of three kinds of carboxymethylinulin prepared with m（inulin） ：m（chlorracetic acid） = 1：1.1,1：1.6 and 1：2. 2 were 0. 34,0. 43 and 0.48 respectively.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2007年第1期83-85,共3页
Fine Chemicals
关键词
羧甲基菊粉
取代度
光度滴定法
carboxymethylinulin
degree of substitution
spectrophotometric titration
