本体光交联对热塑性淀粉塑料性能的影响

将光引发剂二苯甲酮直接与淀粉和甘油共混，并通过挤出注塑工艺制备了热塑性淀粉（TPS）塑料，研究了不同紫外光照时长对其力学、动态热力学、热稳定和耐水性能的影响。结果表明，当紫外光照时长为15 min时，TPS可形成最佳的交联网络结构，显著提高其性能，拉伸强度，弯曲强度，冲击强度分别可达4.57 MPa、7.1 MPa及69.39 kJ/m2；储能模量有所提高，玻璃化转变温度达到最高，Tβ和Tα分别为-35.63 ℃和53.96 ℃；最大分解速率对应的峰值温度（Tp）由TPS的317.81 ℃提高到330.48 ℃；表面接触角由纯TPS的42.3 °增加至77.2 °，显著提高了耐水性能。

Effect of Bulk Photo-crosslinking on Properties of Thermoplastic Starch Plastics

Thermoplastic starch (TPS) was prepared by twin-screw extruder with benzophenone as a photoinitiator and glycerin as a plasticizer, and the effect of UV irradiation time on the mechanical properties, dynamic thermo-mechanical properties, thermal stabilities and water resistance of the resulting TPS were investigated. The results indicated that an optimum crosslinked network structure was formed with UV irradiation for 15 min, which led to an effective enhancement in mechanical properties and water resistance. The tensile strength, bending strength and impact strength of TPS were 4.57 MPa, 7.1 MPa, 69.39 kJ/m2, respectively, and its storage modulus was also improved. Moreover, the glass transition temperature reached a maximum value at this condition with a Tβ of -35.63 ℃ and a Tα of 53.96 ℃. The peak temperature of TPS corresponding to the maximum decomposition rate increased from 317.81 ℃ to 330.48 ℃, and its contact angle increased from 42.3 ° to 77.2 °, indicating the water resistance and water absorption of TPS were improved effectively.