羧甲基棉花纤维素的制备与结构表征

Synthesis and characterization of the Carboxymethyl Cotton Cellulose

以脱脂棉作为纤维素原料,氯乙酸作为反应试剂,探讨了不同碱化条件下脱脂棉羧甲基化反应,并用红外光谱初步对产物进行了结构表征,以酸碱滴定测定了取代度。结果表明:用质量分数为25%NaOH溶液,以脱脂棉纤维素(单元)与氢氧化钠物质的量之比为1:4,碱化一小时,脱脂棉纤维素(单元)与氯乙酸物质的量之比为7:20,保温65℃,反应时间为7h。得到的羧甲基化脱脂棉纤维素取代度最高,为7。313%。

Cotton and chloro-acetic acid were used as raw materials, under alkaline condition, the carboxy-methyl cotton cellulosewas synthesized, and characterized by IR, thedegreeof substitution was detected by acid-basetitration. Theresult indicated the best procedure for the synthesis of carboxy-methyl cotton cellulose was that, cotton treated with 25% NaOH for 1 hour, theratio of cellulose/ NaOH was1:4, chloro-acetic acid solution wasadded dropwise, and theratio of cellulose/ chloro-acetic acid was7:20, keep thetemperatureat 65℃ for 7 hours, thehighest degreeof substitution was7.313%.