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对壳聚(寡)糖化学改性合成不同取代度长链的棕榈酸壳聚(寡)糖酯,于8%氢氧化钠、6.5%硫脲、8%尿素溶剂中制备出棕榈酸壳聚(寡)糖酯/复合膜并研究其性能。FT-IR结果表明,棕榈酸壳聚(寡)糖酯与纤维素能形成氢键,具有一定的相容性;XRD谱图表明,棕榈酸壳聚糖酯的加入会稍微降低复合膜的结晶度,而棕榈酸壳寡糖加入会使复合膜的结晶度增加15.8%;复合膜的接触角随棕榈酸壳聚(寡)糖酯含量的增加分别由19.9%增加到39.0%和39.6%,疏水性能增加。最大拉伸应力在棕榈酸壳聚(寡)糖酯含量6%时达到最大,分别为23.6MPa和33.1MPa,比纯纤维素膜提高了0.56倍和1.80倍。抗菌性能测试显示,复合膜对大肠杆菌的抗菌性大于纤维素膜,且随棕榈酸壳寡糖酯含量的增加先增强再减弱,在6%时达到最大的2.39cm抑菌圈直径,比未改性壳寡糖纤维素膜抑菌圈直径增大14.9%。
Poly (oligo) sugar palmitate with different degree of substitution was synthesized by chemical modification of chitosan (oligo) saccharides, and chitosan was prepared from 8% sodium hydroxide, 6.5% thiourea and 8% urea. (Oligo) sugar ester / composite membrane and study its performance. FT-IR results showed that the poly (oligo) sugar ester of palmitic acid shell could form hydrogen bond with cellulose, and had certain compatibility. The XRD spectrum showed that the addition of chitosan palmitate could reduce the crystallization of the composite film slightly While the addition of palmitic chitooligosaccharides increased the crystallinity of the composite membrane by 15.8%. The contact angle of the composite membrane increased from 19.9% to 39.0% and 39.6% with the increase of poly (oligo) Hydrophobicity increased. The maximum tensile stress reached the maximum at 6% poly (oligo) glycol palmitate, which was 23.6 MPa and 33.1 MPa, respectively, which were 0.56 times and 1.80 times higher than those of pure cellulose film. The antibacterial test showed that the antibacterial activity of the composite membrane against Escherichia coli was higher than that of cellulose membrane, and then increased and then decreased with the increase of the content of palmitic acid chitooligosaccharides, reaching the maximum diameter of 2.39cm at 6% Modified chitooligosaccharide membrane inhibition zone diameter increased by 14.9%.