经甘油增塑的淀粉对湿度敏感、易老化.本研究采用一步法制备超支化聚均苯三甲酸丁二醇酯(H),并与甘油(G)作为玉米淀粉(CS)的共增塑剂混合制备淀粉薄膜.采用傅里叶变换红外光谱(FTIR)和核磁共振氢谱(1 H NMR)证实了超支化聚均苯三甲酸丁二醇酯的结构,并研究了共增塑剂对淀粉相互作用、结晶度、拉伸性能、抗老化性、热稳定性、透光率和吸湿性的影响.结果表明,聚均苯三甲酸丁二醇酯/甘油对淀粉薄膜的韧性、抗老化、透光性和吸湿性有协同作用.聚均苯三甲酸丁二醇酯/甘油配比为5/25 的淀粉薄膜(CS/H5G25)具有最大的断裂伸长率、最高的透光率、最佳的抑制淀粉重结晶的能力以及最低的吸湿率(RH>68%).CS/H2G28 薄膜储存3、15 和30d的断裂伸长率分别为85.9%、103.1%和77.2%,分别是CS/G薄膜的2.8 倍、2.3 倍和3.7 倍.这不仅取决于各组分之间的相互作用,还可能与组分之间的相容性有关.聚均苯三甲酸丁二醇酯/甘油在增塑淀粉方面具有潜在的应用价值.
Starch plasticized by glycerol was sensitive to humidity and aging easily.In this study,hyperbranched poly(butanediol trimesic acid ester)was prepared via one-step method,and it was mixed with glycerol as co-plasticizer of corn starch(CS)to prepare starch films.The Fourier transform infrared spectroscopy(FTIR)and hydrogen nuclear magnetic resonance(1 H NMR)were used to certify the structure of hyperbranched poly(butanediol trimesic acid ester).The interaction,crystallinity,mechanical properties,anti-aging,thermal stability,transmittance and moisture absorption of starch were studied.The results illustrate that poly(butanediol trimesic acid ester)/glycerol shows synergistic effect on the toughness,anti-aging,transmittance and moisture adsorption of starch films.The starch film with poly(butanediol trimesic acid ester)/glycerol at 5/25(CS/H5G25)has the maximum elongation at break,the highest transmittance,the optimal ability to inhibit the long-term degradation of starch,and the lowest moisture absorption above RH 68%.Elongation at break of CS/H5G25 film stored for 3,15 and 30 d are 85.9%,103.1%and 77.2%,respectively,which are 2.8,2.3 and 3.7 times that of CS/G film.These not only depend on the interaction between the components,but also may be related to the compatibility between the components.Poly(butanediol trimesic acid ester)/glycerol has potential application value in plasticized starch.