| 摘要 |
PURPOSE:To produce a hydrogel having a controlled gelation rate and improved strength and stability by allowing partially acidified sodium carboxymethylcellulose to gel with a polyvalent metal ion. CONSTITUTION:A strong acid in an amount equivalent to 0.5-5.0 N with respect to the chemical equivalent of the carboxymethyl groups of CMC is added to an aqueous solution containing 2-7wt.% CMC of an average degree of carboxymethylation of 0.30-1.50 and a viscosity (in a 1wt.% aqueous solution at 25 deg.C and 60rpm) of 10-10000cp, and the mixture is allowed to stand under agitation for 1-3hr to obtain a partially acidified sodium carboxymethylcellulose. An aqueous solution containing 0.5-10wt.% polyvalent metal salt (e.g. potassium alum) is added to an aqueous solution containing 0.5-10wt.% partially acidified sodium carboxymethylcellulose to obtain a hydrogel comprising the partially acidified carboxymethylcellulose polyvalent metal salt. |
