对二甲基氨基肉桂醛与天然棕色棉的显色反应特性

摘要

Since chemical components and structure of naturally brown cotton(NBC)and the common white cotton are quite similar,it is hard to identify the two by using common method.Based on the chemical characteristics of the pigments of NBC,aromatic aldehydes could react with the polyphenolic pigments of NBC to change the color of fiber,which could be used to identify the NBC.In this study, 2-Dimethylaminocinnamaldehyde was used as the reagent to study the effects of reagent concentration, HCl concentration,reaction temperature and reaction time on the color on color of NBC.The results show that NBC could be effectively identified under the following conditions:reaction temperature 50℃,3% HCl and 0.05% 2-Dimethylaminocinnamaldehyde,time 2 min.%天然棕色棉与普通白棉化学成分和结构十分接近,常规的鉴别方法难以快速、方便地鉴别两者.根据天然棕色棉色素的化学性质,利用芳香醛与纤维中的多酚色素反应改变纤维的颜色,可快速鉴别天然棕色棉.本研究选择了对二甲基氨基肉桂醛作为反应试剂,研究了反应试剂质量分数、盐酸体积分数、温度、时间对天然棕色棉纤维颜色的影响.结果表明:在50 ℃,盐酸体积分数3%,对二甲基氨基肉桂醛质量分数0.05%的条件下反应2 min,即可有效鉴别真假天然棕色棉纤维.