摘要
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1～3h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。
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,R-10,polymerization degree,adsorption capacity for I2 and cellulose crystal were not obvious contrast to temperature and concentration.
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2010年第5期96-100,共5页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
南京林业大学人才创新基金项目
关键词
大麻秆浆
碱预处理
R-10值
聚合度
碘吸附值
纤维素晶型
hempen pulp
alkali pretreatment
R-10
polymerization degree
adsorption capacity for I2
cellulose crystal
