不同干燥条件下壳聚糖膜表面的微观结构及微观力学性能

以自然风干(NW)、真空干燥(VD)及红外干燥(ID)三种干燥方式制备了壳聚糖膜.利用原子力显微镜(AFM)研究这三种壳聚糖膜的表面形貌及微观力学性能.实验结果表明VD和ID改善了膜材料的表面平整度,膜表面粗糙度分别为(5.47±1.34)和(2.79±0.93)nm,均显著低于NW膜((30.67±8.06)nm).干燥条件对壳聚糖膜的微观力学性能有较大影响:ID壳聚糖膜的粘附力((2595.0±68.5)pN)显著大于NW壳聚糖膜((982.6±149.3)pN)和VD壳聚糖膜((1817.9±279.2)pN);而ID壳聚糖膜的杨氏模量((158.8±15.2)MPa)则低于NW壳聚糖膜((204.3±22.7)MPa)和VD壳聚糖膜((195.8±14.6)MPa)的.

Microstructure and Micromechanical Properties of Chitosan Films under Different Drying Conditions

Chitosan films were prepared by wet casting followed by natural withering (NW), vacuum drying (VD), and infrared drying (ID). Atomic force microscope (AFM) was used to study the effects of these three drying methods on the microstructural and micromechanical properties of the chitosan films. Results showed that VD and ID effectively enhanced the planeness and evenness of the chitosan films. The average roughness of the VD films ((5.47± 1,34) run) and the ID films ((2.79±0.93) nm) were lower than that of the NW films ((30.67±8.06) nm). The adhesion force of the ID films ((2595.0±68.5) pN) was larger than that of the NW films ((982.6±149.3) pN) and the VD films ((1817.9±279.2) pN). The Youngs modulus of the ID films ((158.8±15.2) MPa) was less than that of the NW films ((204.3±22.7) MPa) and the VD films ((195.8±14.6) MPa).