采用氢氧化钠溶液对大麻秆浆进行预处理，研究了温度、氢氧化钠浓度、预处理时间对纤维得率、R-10值、聚合度、碘吸附值和纤维素晶型的影响。结果表明：低温下氢氧化钠溶液对分子质量较低的纤维素有较强的溶解能力，温度越低，纤维素可溶的分子质量分布越宽，且纤维素Ⅰ越易通过氢氧化钠溶液的润胀转变为纤维素Ⅱ。适当提高氢氧化钠溶液的浓度有助于浆料中半纤维素及低分子质量纤维素的溶解，有利于纤维素的充分润胀。当氢氧化钠质量分数超过9 %时，纤维素的晶型开始明显由纤维素Ⅰ转变为纤维素Ⅱ,导致可及度降低。在预处理时间为1~3 h时，预处理时间对纤维得率、R-10值、聚合度、碘吸附值及纤维素晶型等的影响不大。
Abstract
Pretreatment of hempen pulp with sodium hydroxide were carried out, effects of NaOH concentration, pretreatment temperature and time on the yield, R-10 value, polymerization degree, iodine adsorption value and crystal form of fibers were investigated. The results showed that the dissolving ability of NaOH to the cellulose with low molecular weight was strong at low temperature . The lower temperature was, the wider of molecular weight distribution of cellulose dissolved was, and the cellulose Ⅰ transforms into cellulose Ⅱ more easily because of swelling by the NaOH solution. To increase NaOH concentration properly was helpful for the dissolution of hemicellulose and the low molecular weight cellulose in the pulp, and was useful to the sufficient swelling of cellulose. Cellulose Ⅰ was obviously transformed into cellulose Ⅱ as NaOH concentration was higher than 9 %, and resulted in decreasing of the accessibility. Effects of pretreatment time between 1 and 3 hour on the yield of fibers, R10, polymerization degree, adsorption capacity for I2 and cellulose crystal were not obvious contrast to temperature and concentration.
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参考文献
[1]吴红玲,蒋少军,丁丽文. 大麻纤维性能及其产品的研制生产[J]. 毛纺科技,2004(6):36-39. [2]Nyktera M, Kymlinen HR, Thomsen A B, et al. Effects of thermal and enzymatic treatments and harvesting time on the microbial quality and chemical composition of fibre hemp (Cannabis sativa L.)[J]. Biomass and Bioenergy, 2008, 32(5): 392-399. [3]张建春,张华. 工业用大麻纤维综合开发研究[J]. 中国麻业科学,2007,29(B02):63-65,67. [4]Nevell T B, Zeronian S H. Cellulose Chemistry and Its Application[M]. UK: Ellis Horwood Limited, 1985. [5]李晓东. 关注人造纤维工业发展,加速国产高纯度漂白阔叶木浆的开发[J]. 上海造纸,2003,34(1):19-22. [6]王佩卿. 木材化学[M]. 北京:中国林业出版社,1987. [7]付欣,唐爱民,张宏伟,等. 纤维素纤维的可及度及多孔性能表征研究[J]. 造纸科学与技术,2005,24(6):49-53. [8]查纯喜,金华进,顾利霞. 纤维素在氢氧化钠/硫脲/尿素/水溶液中的溶解和溶液特性[J]. 东华大学学报:自然科学版,2008,34(1):20-23. [9]王怀芳,朱平,张传杰. 氢氧化钠/尿素/硫脲溶剂体系对纤维素溶解性能研究[J]. 合成纤维,2008,37(7):28-32. [10]苏茂尧,由利丽,高洸,等. 液氨预处理对纤维素可及度和反应性的影响[J]. 纤维素科学与技术,1998,6(3): 44-51. [11]Ouajai S, Shanks R A. Composition, structure and thermal degradation of hemp cellulose after chemical treatments[J]. Polymer Degradation and Stability, 2005, 89: 327-335. [12]高洁,汤烈贵. 纤维素科学[M]. 北京:科学出版社,1996. [13]李松晔,刘晓非,庄旭品,等. 棉浆粕纤维素的超声波处理[J]. 应用化学,2003,20(11):1030-1034. [14]王献玲,方桂珍. 不同活化方法对微晶纤维素结构和氧化反应性能的影响[J]. 林产化学与工业,2007,27(3):67-71. [15]Zhu S D, Wu Y X, Yu Z N, et al. Microwaveassisted alkali pretreatment of wheat straw and its enzymatic hydrolysis[J]. Biosystems Engineering, 2006, 94(3): 437-442.
基金
收稿日期：2009-12-15修回日期：2010-04-12基金项目：南京林业大学人才创新基金项目作者简介：吴晶晶(1984—),硕士生。 *洪建国(通信作者):教授。Email: jghong@njfu.com.cn。引文格式：吴晶晶,李小保,叶菊娣,等. 碱预处理对大麻秆浆纤维素性质的影响[J]. 南京林业大学学报:自然科学版,2010,34(5):96-100.
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