本研究針對幾丁聚醣(chitosan)與果膠(pectin)這兩種天然的多醣類高分子進行複合材料的研究。由於幾丁聚醣分子帶正電而果膠帶負電,故兩種分子能以離子鍵的作用方式形成離子型複合材料。另一作用方式則是在離子鍵之外,再透過以EDC及NHS的交聯作用使兩種分子之間還有共價鍵的形成,稱之為離子與共價型複合材料。從機械性質測定的結果顯示,離子型複合基質在果膠比例提高的情況下,其強度從0.05 MPa上升一倍至0.12 MPa左右。另外在離子與共價型複合基質方面,隨著交聯劑濃度的提高,複合基質在強度上從0.08 MPa上升至0.12 MPa左右,但在延展性方面卻不受影響。另外在離子型複合材料方面,當果膠比例提高時,複合材料之親水性也隨之上升,而在離子與共價型複合材料方面,隨著交聯劑濃度上升,複合材料之親水性也跟著變佳。從DSC的結果,在離子型或離子與共價型複合材料,其兩種物質之間都因為內部作用力的增強,使其熱性質發生變化,Tg值上升。果膠的添加亦增加了幾丁聚醣之降解性與細胞相容性。本研究成功的以幾丁聚醣與果膠這兩種多醣類高分子,以離子鍵或離子與共價鍵的方式進行複合,開發出新型的複合材料,此一複合材料具有強度較高、親水性佳、細胞相容性較優等特點,故它在生醫材料及其相關領域具有其應用的潛力和價值。
In this research, chitosan and pectin, two kinds of natural polysaccharide were used to form composite materials. Because chitosan is poly-cationic and pectin is poly-anionic, the ionic interaction between these two polymers form polyelectrolyte. Besides, another kind of composite material was formed by not only the ionic interaction, but also the covalent bond between two polymers by the addition of the cross-linking agents—EDC & NHS. The mechanical tests indicated that with the increase of the ratio of pectin/chitosan, the mechanical strength of composite material formed by the ionic interaction increased from 0.05 MPa to about 0.12 MPa. Besides, the mechanical strength of the composite material formed by the (ionic and covalent) bond increased from 0.08 MPa to 0.12 MPa, but the strain at max. load didn’t decrease. The measurement of contact angles revealed that with the increase of the ratio of pectin/chitosan, the hydrophilicity of the composite materials increased. With the increase in the crosslinking agent concentration, the hydrophilibility of the composite materials increased, too. The DSC analysis showed that the interactions between two the polymers increased the values of Tg(glass transition temperature). The rate of degradation and the biocompatibility of chitosan were also enhanced by the addition of pectin. In this research, new composite materials were successfully made of chitosan and pectin using either ionic only or (ionic and covalent bond)interactions. Because of the good mechanical strength, high hydrophilicity, and excellent cytocompatibility, these composite materials have application potential in biomaterial-related fields.