制备工艺对果胶/壳聚糖复合膜力学性能的影响

Effect of Preparation Process on the Mechanical Properties of Pectin/Chitosan Composite Membrane

采用5种不同工艺制备果胶/壳聚糖(PEC/CS)复合膜,研究了成膜因素对膜力学性能的影响,并利用FT-IR、XRD、SEM表征其结构。结果表明:先将壳聚糖/果胶在乙酸溶液中生成絮状沉淀,再用甲酸溶解后制备的复合膜光滑透明,拉伸强度能达到45.38MPa。FT-IR分析显示,果胶和壳聚糖通过-COOH和-NH2之间的静电作用和氢键作用生成复合物。XRD分析显示,果胶的加入降低了壳聚糖的结晶度,形成网络结构,提高了复合膜整体的力学性能。SEM分析显示,果胶/壳聚糖复合絮状沉淀的表面,可见明显纵横交错的条痕,说明果胶和壳聚糖分子之间发生了复合反应。

Five kinds of process were applied to prepare pectin/chitosan（PEC/CS） composite membranes and the effect of membrane-forming conditions on the mechanical properties were explored,FT-IR,XRD and SEM were adopted to describe the structure of membrane. The results indicated that,the membrane prepared by dissolving the flocculent precipitate（formed by dissolving PEC/CS in the solution of acetic acid） with formic acid solution was smooth and transparent,and its tensile strength could reach 45.38MPa,which was 1.42 times as that of gelatin membrane. The result of FT-IR analysis indicated that,a polyelectrolyte reaction happened between pectin and chitosan molecules through electrostatic and hydrogen bond interaction between-COOH and-NH2,and in this way,a composite material was formed. The result of XRD analysis showed that,the adding of pectin reduced the crystallinity of chitosan,a network structure was formed,and the mechanical property of the composite membrane was improved. The result of SEM analysis showed that,clear streaks could be observed in the surface of PEC/CS composite flocculent precipitate,and this indicated the poly-reaction occurred between pectin and chitosan molecules. Based on these experiment results.