医用棉纱布的羧甲基化改性

Carboxymethylation of Medical Cotton Gauze

采用两步加碱水媒法,并通过浸轧的方式对医用棉纱布进行羧甲基化改性,制备高吸水性医用敷料。考察了烧碱浓度、烧碱与氯乙酸的配比对样品的取代度、吸水性、透气性和力学性能的影响,确定了最佳工艺条件。结果表明:随着第一步烧碱浓度和第二步烧碱与氯乙酸的摩尔比的增加,羧甲基化医用棉纱布的取代度和吸水性均呈现明显的上升趋势。当第一步加碱的烧碱浓度为20%,烧碱与氯乙酸的摩尔比为2.7:1时,样品的拉伸断裂强力及伸长率上升到最大值,羧甲基化医用棉纱布表现出良好的柔韧性,同时也具有较好的透气性。此时,样品的取代度为0.17,吸水率达到170.98%,纱布表面形成了均匀有效的水凝胶保护层。

Two step alkalization process and padding method have been adopted on carboxymethylation of gauze（CM-gauze） in aqueous medium to prepare superabsorbent wound dressing.The influences of sodium hydroxide concentration and stoichiometric ratio of sodium hydroxide and chloroacetic acid on the degree of substitution（DS）,absorption,mechanical properties and air permeability were investigated.The results showed that the DS and absorption of CM-gauze were both raised with the increases of the concentration of sodium hydroxide at first step and ratio of sodium hydroxide and chloroacetic acid at second step.When the concentration of sodium hydroxide at first step was 20% and ratio of sodium hydroxide and chloroacetic acid was 2.7：1,CM-gauze reached the maximum tensile strength and elongation at break.The sample with good flexibility and air permeability had DS of 0.17 and absorption of 170.98% under optimal conditions.And a uniform layer of effective hydrogel was formed on the surface of CM-gauze.