ZHOU Cai-rong,XU Min-qiang,WANG Xiao-song,WANG Hai-feng
Abstract:
In view of the actual problem and the characteristics of carboxymethyl cellulose ( CMC) synthesisprocess,the waste liquor of the viscose fiber industry as main raw materials with wood pulp was used for pro-ducing carboxymethyl cellulose (CMC). The effect of gradient heating in ethrification process,along with theaddition of urea,sodium silicate sodium in alkalization process and the addition of tetraborate in the etherifica-tion process on the properties of the modified CMC were studied and explored by single factor test.The resultsshow that the modified CMC with the best properties were obtained by third-order heating ( first-order tempera-ture of 55 ℃,temperature of the second order of 70 ℃,and third-order temperature of 80 C ) for etherifica-tion reaction. Meanwhile, 3% urea and 5% alkaline sodium silicate were also added in alkalization process,and 6% tetraborate was added in the etherification process.The viscosity of the product CMC was up to 2486.7 MPa· s,the substitution degree was 0.65,the acid-viscosity ratio was 0.416,salt-viscosity ratio was 0.547. Compared with previous modified CMc,the indexes were promoted by 97.17%,23.63%,57.53%and 45.55 % for aboved-mentioned performances,respectively.