以玉米淀粉为原料，戊二酸酐为酯化剂，蒸馏水为反应溶剂，研究并分析了在制备戊二酸淀粉酯的过程中淀粉乳初始浓度、反应时间、反应温度、体系pH值和戊二酸酐用量对产物取代度的影响。通过单因素实验和正交实验，得出制备戊二酸淀粉酯的最佳工艺条件：淀粉乳浓度为40%（质量分数，下同），反应时间为2 h，反应温度35 ℃，体系pH为8.5。采用傅里叶变换红外光谱(FT-IR)、X射线衍射仪(XRD)及扫描电子显微镜(SEM)对原玉米淀粉和不同取代度的产物进行了结构表征分析。FT-IR显示戊二酸淀粉酯在1733 cm-1处和1555 cm-1处出现了新的吸收峰，其中1733 cm-1处为C=O的伸缩振动吸收峰，1555 cm-1处为游离的-COO-的反对称伸缩振动吸收峰，表明了淀粉分子中成功接入了戊二酸基团；XRD分析显示改性后的淀粉仍属于A型结晶结构，表明了反应主要发生在无定形区。

Glutaric acid starch ester was prepared from native corn starch by aqueous-phase method, using glutaric anhydride (GA) as the esterifying agent, and distilled water as the reaction solvent. The effects of initial starch slurry concentration, reaction time, reaction temperature, pH value and the amount of glutaric anhydride on the degree of substitution (DS) during the preparation were also investigated. Optimum reaction conditions for GA starch preparation, obtained by single-factor and orthogonal testing were as follows: starch slurry concentration 40% (m/m), reaction time 2 h,reaction temperature 35 ℃ and pH 8.5. The structures of native corn starch and GA starch were characterized and analyzed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). FTIR results showed that two new absorption peaks appeared at 1733 cm-1 and 1555 cm-1, attributed to C=O stretching vibration and free -COO- antisymmetric stretching vibration, respectively, indicating that GA was successfully introduced into the starch molecules. The results of XRD analysis revealed that GA starch still showed a Type-A crystal structure, suggesting that the reaction occurred mainly in the amorphous region.

广州市对外科技合作项目（201508030020）。