【摘要】 采用HNO3/H3PO4-NaNO2氧化体系选择性氧化棉织物得到单羧基纤维素,然后与壳聚糖溶液发生酰胺交联反应,制备出壳聚糖接枝改性的单羧基棉织物。通过研究HNO3/H3PO4-NaNO2氧化时间对单羧基棉织物羧基含量、断裂强力及壳聚糖接枝后棉织物增重率的影响,得出氧化时间在45 min时壳聚糖接枝棉织物的最大增重率为5.52%。固相CP/MAS13C NMR、FT-IR、SEM和XRD等测试方法分析表明,HNO3/H3PO4-NaNO2体系将棉纤维葡萄糖单元中C6位伯羟基选择性氧化成羧基,壳聚糖分子中的氨基与氧化棉织物上的活性羧基反应形成C—N酰胺化学键,壳聚糖在织物表面共价交联成膜。壳聚糖接枝反应后,单羧基棉织物的结晶度从65.37%下降到60.86%,壳聚糖改性棉织物的断裂强力、白度及毛细效应有所减小,但折皱回复角明显提高。更多还原

【Abstract】 Cotton fabrics were selectively oxidized by HNO3/ H3PO4-NaNO2system and obtained monocarboxyl cellulose,followed by amide crosslinking reaction in chitosan solution,thus prepared chitosan graft-modified monocarboxyl cotton fabric. Effects of oxidation time of HNO3/ H3PO4-NaNO2on the carboxyl content,breaking strength and weighting percentage of the graft modified cotton fabric were studied and it was found that the maximum weighting percentage of 5. 52% was obtained when the oxidation time is 45 min. CP / MAS13C NMR,FT-IR,SEM and XRD tests demonstrated that the primary hydroxyl at C6 site in glucose units of cotton cellulose was selectively oxidized into carboxyl group by HNO3/ H3PO4-NaNO2system,subsequently the amido bond of C—N was formed between amino groups in chitosan and active carboxyl groups on theoxidized cotton fabrics and chitosan film formed on the surface of the oxidized cotton fabrics by the covalent crosslinking. After chitosan graft reaction,the crystallinity of monocarboxyl cotton fabric decreased from 65. 37% to 60. 86%,the breaking strength,whiteness and capillary effect slightly reduced,whereas the wrinkle recovery angle significantly increased.更多还原