采用硝化棉(NC)含氮量及其分布均匀性测试仪,考察了硝化系数、精制棉的膨润预处理和超声预处理三因素对硝化棉含氮量及氮量分布均匀性的影响规律.结果表明,NC的含氮量随硝化系数的增大而增大.当硝化系数分别为40、50和80时,NC含氮量分布值Dε较小,当硝化系数为20或100时,Dε值均显著增大；采用硫脲和尿素水溶液预处理精制棉,对NC的含氮量没有影响,但可使NC的氮量分布变窄；随着精制棉超声处理时间的延长,NC的含氮量逐渐增大.当超声波处理时间分别为10和30 min时,NC的含氮量分布明显变宽,NC的相对分子质量降低.当处理时间为60 min时,NC的氮量分布与未处理前相比略微变窄,NC的相对分子质量略有增大.%The effect of three factors involving nitrification coefficient, swelling and ultrosonic pretreatment of cellulose on the nitrogen content and its distribution uniformity of nitrocellulose were investigated by a testing instrument for nitrogen content and distribution uniformity of NC. The results show that the nitrogen content of NC increased with increasing nitrification coefficient; the nitrogen distribution value Dε were low when the nitrification coefficient was 40,50 and 80, while it significantly increased at 20 or 100; Swelling pretreatment of cotton cellulose via thiou-rea and urea aqueous solution did not affect the nitrogen content of NC, but it can narrow NC's nitrogen distribution; prolonging the ultrasonic treatment time of cotton cellulose within the studing scale resulted in an increase of nitrogen content of NC. The nitrogen distribution of NC became significantly wider and the moleculor weight decreased after 10min or 30 min ultrasonic treatment, while the nitrogen distribution became slightly narrower comparing with that of untreatment when ultrasonic treatment time prolonged to 60min, and the molecular weight increased slightly.
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