碱脲体系对稻草机械浆强度性能的影响研究

The effect of alkali-urea solution treatment on the strength property of straw refining mechanical pulp

采用氢氧化钠-硫脲-尿素水溶液在中高温条件下处理稻草盘磨机械浆,通过用碱量、纤维浓度、处理温度和处理时间等参数的单因素试验探究该溶剂对稻草纤维成纸强度性能的影响。研究表明:在用碱量4%、处理时间40m i n、处理温度50℃、纤维浓度15%的条件下,稻草机械浆的强度性能最佳,以原浆强度为参比,经处理后纤维的抗张指数和耐破指数分别提高75.6%和80.9%,同时其成纸松厚度下降13.6%,但耐折度无明显变化。此外,处理前后浆料纤维无定形区和结晶区的整体结构不受影响,纤维中碳、氢、氧三种元素的质量比没有明显变化,但氮元素含量降低明显。

In this paper,NaOH-thiourea-aqueous urea solution was applied in the treatment of straw refining mechanical pulp(straw RMP)under medium and high temperature conditions.The effect of the solution on paper strength was studied through single-factor tests on alkali dosage,fiber consistency,treating temperature and duration.The results show that straw RMP could achieve the best strength property under the alkali dosage of 4%,fiber consistency of 15%,treating temperature of 50℃and treating duration of 40min.Compared with virgin pulp,the treated straw fiber will see significant increase in tensile index(+75.6%)and burst index(+80.9%),and 13.6%decrease of paper bulkness,with no obvious changes in folding endurance.Besides,the overall structure of the amorphous and crystalline region could not be affected by the solution.There was no significant variation in the content of element C,H,and O,whereas element N’s content decreased obviously.