低取代度糯玉米淀粉醋酸酯的制备

Preparation for Starch Acetate from Waxy Corn with Low Degree of Substitution

以糯玉米淀粉为原料,醋酸酐为乙酰化试剂,氢氧化钠为催化剂,硫酸钠为膨胀抑制剂,制备了低取代度糯玉米淀粉醋酸酯。考察了醋酸酐用量、膨胀抑制剂用量、pH值、反应温度、反应时间等因素对糯玉米淀粉醋酸酯乙酰基含量和反应效率的影响。试验结果表明,醋酸酐用量、硫酸钠用量、pH值、反应温度和反应时间对糯玉米淀粉醋酸酯的取代度有影响。通过试验得到制备低取代度糯玉米淀粉醋酸酯的较佳工艺条件为:pH值9.0,反应温度30℃,反应时间60min,硫酸钠用量2%(以淀粉干基质量计)。

A study was conducted to prepare starch acetate using waxy corn starch as material, acetic anhydride as acetylation reagent, sodium hydroxide as catalyst and sodium sulfate as gelatinization inhibitor. Effects of factors such as amount of acetic anhydride, reaction time, reaction temperature, pH value and amount of sodium sulfate on acetyl content of acetate starch and reaction efficiency were discussed. Results showed that amount of acetic anhydride, amount of sodium sulfate, pH value, reaction time and reaction temperature had certain effect on the degTee of substitution of starch acetate. The optimal technical conditions were obtained as pH 9.0, reaction temperature 30 ℃, reaction time 60 minutes, amount of sodium sulfate 2% （calculate by the dry weight of starch）.