棉秆韧皮制备可降解纤维素膜的研究

发布时间：2018-09-03 07:08

【摘要】：近年来,随着人们环保意识的觉醒和社会的发展,人们越来越重视对天然纤维的开发和研究。从植物的茎、叶等部位提取纤维素不论从原料上还是加工过程都受到了人们的密切关注。棉秆是一种可再生的天然纤维素纤维,它的韧皮中存在较多的韧皮纤维素纤维。因此,提倡开发利用棉秆,有利于实现可持续发展战略。首先,本课题参考麻纤维的化学成分测定方法对棉秆韧皮纤维的各成分含量进行了测定。得出棉秆韧皮的成分含量分别为:纤维素27.965%,半纤维素25.186%,木质素23.774%,水溶物17.695%,果胶物质3.443%,脂蜡质1.973%。并和稻秸秆、亚麻、黄麻等植物的各成分含量进行了对比讨论,发现棉秆韧皮中的半纤维素和木质素含量相对偏高。棉秆韧皮纤维的脱胶采用比较成熟的化学处理方法,分别讨论了不同Na OH浓度、碱煮时间和碱煮温度对脱胶效果的影响。具体的脱胶工艺为:预处理→烘干→浸酸→水洗→烘干→一次碱煮→水洗→烘干→打纤→二次碱煮→水洗→烘干→打纤→酸洗→水洗→烘干→脱胶棉秆皮纤维。通过对不同实验条件下的结果进行评价选择的工艺条件是:Na OH质量浓度为12 g/L,碱煮时间为90 min,碱煮温度为90℃。本文采用硝酸-乙醇法和氢氧化钠法从棉秆韧皮中提取纤维素,分别探讨了不同的硝酸-乙醇溶液浓度和氢氧化钠溶液浓度、煮沸时间对提取效果产生的影响。综合考虑选择的最佳提取条件是:无水乙醇与浓硝酸的体积比为4:1。此实验条件下提取的纤维素纯度最高为90.67%,提取率为34.26%。再采用不同的方案配制铜氨溶液,并研究了棉秆韧皮纤维素在不同铜氨溶液中的溶解情况,选择将浓氨水加入到硫酸铜溶液中的方法来配制铜氨溶液。溶解成型的纤维素膜要经过塑化处理即在30%的丙三醇溶液中浸泡4 h后取出晾干保存。将丙三醇增塑处理和未处理的纤维素膜进行了透光率、力学性能等的对比发现,经过增塑处理的纤维素膜透光率、力学性能都有所提高。将纤维素膜与塑料地膜在土壤中的保湿、保温性能进行了对比,综合考虑得出纤维素膜更有利于植物生长,而且降解实验表明,纤维素膜具有良好的降解性能,对环境保护起到重要作用。
[Abstract]:In recent years, with the awakening of environmental awareness and social development, people pay more and more attention to the development and research of natural fiber. People pay close attention to extracting cellulose from stem, leaf and other parts of plant, not only from raw material but also from processing process. Cotton stalk is a renewable natural cellulose fiber, and there are more phloem cellulose fibers in its phloem. Therefore, promoting the development and utilization of cotton stalk is conducive to the realization of sustainable development strategy. Firstly, the content of the components of cotton stem phloem fiber was determined by referring to the chemical composition determination method of hemp fiber. The results showed that the components of cotton stem phloem were cellulose 27.965, hemicellulose 25.1866, lignin 23.774, water soluble 17.695g, pectin 3.443cm, lipid wax 1.973. The contents of hemicellulose and lignin in cotton stalk phloem were higher than those in rice straw flax jute and other plants. The effects of different Na OH concentration, alkali cooking time and alkali boiling temperature on the degumming effect of cotton stalk phloem fiber were discussed. The specific degumming process is as follows: preconditioning drying and soaking with acid and water washing, drying and drying the cotton stalk skin fiber. The technological conditions for evaluating the results under different experimental conditions are as follows: mass concentration of 1: na OH is 12 g / L, alkali cooking time is 90 min, alkali boiling temperature is 90 鈩，

本文编号：2219274