반응표면분석법에 의한 양이온성 옥수수전분 생산의 최적화

Cationic starch is widely used in the paper-making process as a wet-end additive to improve sheet strength and to provide better retention of fines as well as fillers. Cationic corn starch is generally used in most grades of paper because of its cheapness and opulency. Low-substituted cationic starch which has a degree of substitution (DS) of below 0.03 is widely used but regulations pertaining to the total amount of lead present in anionic waste have made paper companies leery about its continued use. As a result, the need for a high-substituted cationic starch which has a DS above 0.04 has been growing. On the basis of the results of the alkali gelatinization initiation concentration (AGIC) of corn starch suspension, the optimization of corn starch cationization was performed by response surface methodology (RSM). When 8% (w/w) cationic reagent was added to the starch suspension with 1.89% (w/w) of Na₂SO₄ and NaOH, after which 6.75 meq/g-starch of AGIC was added at 38.48°C. It appears that cationic starch can be produced with a reaction yield of 67.28% (DS 0.0302) over the course of 18 h. If the cationic reagent is increased to 20% (w/w), more than 24 h was needed to reach the maximum reaction yield. Within 24 h, the optimized cationization process produced cationic corn starch which has a DS of 0.064.