丝素酰胺改性棉织物的结构及性能

Structure and properties of cotton fabric by amide modification of silk fibroin

为获得多功能生态棉织物,采用HNO3/H3PO4-Na NO2体系选择性氧化棉织物引入活性羧基,然后与丝素蛋白反应形成酰胺化学键。研究了HNO3/H3PO4-Na NO2氧化时间对氧化棉织物羧基含量、断裂强力的影响,分析了氧化时间、丝素质量浓度和处理时间对氧化棉织物接枝率的影响,得出氧化时间1 h和接枝时间2 h时,氧化棉织物的丝素接枝率为10.43%。利用红外光谱、扫描电镜等测试手段分析表明:HNO3/H3PO4-Na NO2将棉纤维分子中C6位伯羟基选择性氧化成羧基,丝素的氨基与氧化棉织物的羧基反应生成C—N酰胺键,丝素在织物表面交联成膜;丝素改性棉织物的机械强力、白度稍有降低,而折皱回复性和吸湿性明显提高;丝素改性棉织物承载和缓释的金银花提取物为原棉织物的3.45倍,金银花处理的丝素改性棉织物经30次水洗后仍有较高的抑菌活性。

For producing muhifunctional ecological cotton fabrics, cotton fabrics were selectively oxidized by HNOs/H3PO4-NaNO2 mediate system to introduce the carboxyl groups in cellulose, and then fibroin was bonded with oxidized cotton fabric by the amide reaction. The influence of oxidation time of HNO3/ H3PO4-NaNO2 on carboxyl content and tensile strength of oxidized cotton fabrics was studied, and the influence of oxidation time, mass concentration and treatment time of fibroin on graft yield of oxidized cotton fabric was investigated and the fibroin graft yield of 10.43% was obtained when the oxidation time and graft time were chosen as 1 h and 2 h, respectively. The analysis of NMR, FT-IR, SEM and XPS illustrated that the primary hydroxyl in C6 position in glucose units of cotton fiber was selectively oxidized to carboxyl group by HNO3/H3PO4-NaNO2 system, subsequently the amido bond of C-N was formed by the reaction between amino groups in silk fibroin and carboxyl groups in oxidized cotton fabric and the fibroin film covered on the surface of oxidized cotton fabrics by the covalent crosslinking. The breaking strength and whiteness of fibroin grafted cotton fabrics slightly decreased, whereas the properties of wrinkle recovery and moisture adsorption of modified fabrics markedly increased. 3.45 times as much honeysuckle extract adsorbed on the fibroin grafted cotton fabric was released than original cotton fabric. Furthermore, the fibroin grafted carboxylic cotton fabric treated with honeysuckle extract had a good antimicrobial activity against Staphylococcus aureus and Escherichia coli after 30 washes by water.