对SY 5093—92标准中取代度测定方法的修改商榷意见

Suggestion on the determination method of substitution degree in SY 5093 - 92

在长期的检测工作中发现,用SY 5093—92标准中取代度测定方法,即灰化灼烧法测定水媒法生产的CMC产品的取代度有一定的局限性,同一颗粒大小的样品提纯次数越多,纯度、取代度越低;样品颗粒越小其纯度、取代度受提纯方式的影响越大。通过实验和理论分析证实了这一现象。建议在现行SY 5093—92标准中增加酸化滴定法附则,用来测定水媒法生产的CMC产品的取代度。

Limitation appcares when determining the substitution degree of CMC produced with water-medium method using ashing showed in SY 5093 92. Purity and the substitution degree of CIVIC particles decrease as more purifying performed with the samesize particles and purification methods show greater effect on the two parameters as CMC particles became smaller. Tests and theoretical analysis proved these existence. It is suggested that acidizing treatment and titration should be appended to SY 5093 92 to determine the substitution degree of CMC produced with water-medium method.