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Carboxymethyl cellulose (CMC) is a cellulose obtained by chemical modification of a natural polymer derivative having a ethers structure , containing a large number of carboxyl and hydroxyl groups in the macromolecular chains , has a certain reactivity . Sodium carboxymethyl cellulose (CMC-Na) and the esterification reaction of the long chain fatty acid molecule , the more difficult, and the low degree of esterification . This paper attempts to a higher degree of esterification hydrophobically modified sodium carboxymethyl cellulose in the preparation of a new solvent . First through the stearic acid with thionyl chloride in a medium of n - heptane reacting n- octadecyl chloride , and then use it as a reaction raw material and sodium carboxymethyl cellulose (CMC-Na) esterified in the medium , n - heptane reaction preparing hydrophobically modified sodium carboxymethyl cellulose , sodium carboxymethyl cellulose, by examining in a solvent the ratio of the mass concentrations , octadecyl chloride and carboxymethyl cellulose sodium , the reaction temperature and time influence on the reaction , identified optimum reaction conditions , the product was obtained as the degree of esterification of up to 0.6. Then , under the same reaction conditions , with the n- 10 chloride , dodecyl chloride , tetradecyl chloride , cetyl chloride and stearyl chloride , respectively, and the molar ratio of sodium carboxymethyl cellulose, a glucose unit for 0.08:1 , prepared a series of hydrophobically modified water - soluble sodium carboxymethyl cellulose , and the determination of the HLB value of these modified carboxymethyl cellulose sodium , and the surface tension and the critical micelle concentration, modified product showed certain surfactants . The paper attempts to the coordination crosslinking with eight kinds of metal salts and modified sodium carboxymethyl cellulose found the AlCl 3 Fe (NO3) 3 · 9H < sub > 2 O do crosslinking agent may be prepared with a pH value different occurrence of solid-liquid two phase change of the hydrogel , and the hydrogel samples were characterized by infrared spectroscopy on the formation mechanism of the hydrogel .
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