微波辐射增强改性三维壳聚糖棒材

Three Dimensional Chitosan Rods Reinforced by Microwave Irradiation

通过微波辐射热致交联的方法增强改性三维壳聚糖棒材。结果表明,辐射一定时间后发生的交联反应提高了壳聚糖溶液的旋转粘度;继续增加辐射时间,由于壳聚糖的热交联反应和热分解碳化同时并存,壳聚糖溶液的旋转粘度反而下降了。交联和高温碳化对壳聚糖分子链产生化学和物理的固定作用,使其吸水膨胀困难,从而降低了壳聚糖棒材的吸水率。热交联反应使壳聚糖分子链间形成体型网络状结构,从而有效地改善了三维壳聚糖棒材的力学性能。微波辐射4 min后,壳聚糖棒材的弯曲强度和弯曲模量可达182.8MPa、5.6GPa,比未辐射的壳聚糖棒材分别提高了97.8%、36.6%。

The chitosan（CS） rods were reinforced by thermal cross-linking method through microwave irradiation.The results show that the rotary viscosity of CS solution was increased due to thermal cross-linking reaction,but much more irradiation time would decrease its solution viscosity because of thermal decomposition.Crystallinity of CS was reduced due to the formation of network structure.Bending strength and bending modulus of microwave irradiated CS rods maximized at 182.8 MPa and 5.6 GPa,increased by 97.8%and 36.6%respectively,compared with untreated CS rods.The improvement of mechanical properties can be attributed to the formation of network structure.