THE UNIFORMITY OF DISTRIBUTION OF SUBSTITUENTS ALONG THE CHAIN OF CARBOXYMETHYL CELLULOSE SYNTHESIZE

来源 :Chinese Journal of Polymer Science | 被引量 : 0次 | 上传用户:sam008
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Based on the property that carboxymethylcellulose (CMC ) can be de-graded to anhydroglucose residues by cellulase, the rate constant (K) of enzymatic degra-dation of CMC synthesized in the benzene-ethanol medium has been determined. Further-morel experimental equation K = 2.71× 10~(-2)(DS)~(-1.2) reflecting the relationship betweenK and the degree of substitution (DS) is correlated and used to describe chemical mi-crostructure uniformity of the distribution of substituents along chains effectively. Chainstructure parameters of enzymatic degradation products of CMC-the number of chainbreaks and the percentage of glucose released have been also measured. Average length ofsubstituted and unsubstituted chain segments are calculated simultaneously. Through thestudy of static and dynamic procedures of enzymatic degradation, the method to charac-terize the distribution of substituents of CMC along the chain has been improved. Based on the property that carboxymethylcellulose (CMC) can be de-graded to anhydroglucose residues by cellulase, the rate constant (K) of enzymatic degradation-dation of CMC synthesized in the benzene-ethanol medium has been determined. Further-morel experimental equation K = 2.71 × 10 ~ (-2) (DS) ~ (-1.2) reflecting the relationship between K and the degree of substitution (DS) is correlated and used to describe chemical mi-crostructure uniformity of the distribution of substituent along chains effectively. parameters of enzymatic degradation products of CMC-the number of glucose released have been also measured. Average length of substituted and unsubstituted chain segments are calculated simultaneously. Through the study of static and dynamic procedures of enzymatic degradation, the method to charac- terize the distribution of substituents of CMC along the chain has been improved.
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