柠檬酸甘油共混热塑性淀粉的制备及性质研究

The Preparation and Nature of Citric Acid /Glycerine Blending Thermoplastic Glutinous Rice Starch

以糯米淀粉为原料,加入甘油、柠檬酸制备热塑性淀粉。通过试验得到热塑性淀粉制备的最佳工艺条件,即反应时间60 min、反应温度120℃、柠檬酸与糯米淀粉质量比为0.4∶1、甘油与糯米淀粉质量比为0.3∶1,热塑性糯米淀粉达到最高取代度0.118。并通过红外图谱分析和差示扫描量热检测,证明柠檬酸甘油共混制备的热塑性糯米淀粉与原糯米淀粉相比透明度明显提高,黏度显著降低。处理后的淀粉发生了部分酯化反应,其热稳定性明显提高,增强了热塑性糯米淀粉的生产加工能力。

Glutinous rice starch was adopted as the raw material to prepare a thermoplastic starch with glycerin and citric acid. The best preparation technology condition was obtained in the experiment, as follows： reaction time was 60min, reaction temperature was 120℃, the mass ratio of citric acid and rice starch was 0.4： 1, the mass ratio of glycerol and rice starch was 0.3： 1, and the highest degree of substitution of thermoplastic starch was 0.118. IR spectra analysis and differential scanning calorimetry detection proved that thermoplastic starch blended with citric acid and glycerol had more advantages： while compared with original glutinous rice, the thermoplastic starch＇s transparency was distinctly enhanced and the viscosity was obviously reduced. After the processing, the partial esterifications had been found in starch, and the thermoplastic starch thermostble was distinctly enhanced, so as to improve the productive and processing capacities of thermoplastic starch.