漂白化学针叶木泡沫浆料流变性能的研究  

Study on Rheological Properties of Bleached Chemical Softwood Foam-fiber Suspension

作　　者：陈婷婷 王晨[1,2] 程金兰[1,2] 张辉[1,2] 宜勇钢[1,2] CHEN Tingting;WANG Chen;CHENG Jinlan;ZHANG Hui;YI Yonggang(Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology,Nanjing Forestry University,Nanjing f Jiangsu Province,210037;Jiangsu Co-Innovation Center far Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing,Jiangsu Province,210037)

机构地区：[1]南京林业大学江苏省制浆造纸科学与技术重点实验室,江苏南京210037 [2]南京林业大学江苏省林业资源高效加工利用协同创新中心,江苏南京210037

出　　处：《中国造纸学报》2020年第4期35-41,共7页Transactions of China Pulp and Paper

基　　金：国家水体污染控制与治理科技重大专项(2017ZX07402004);国家自然科学基金(31770627);江苏省高校优势学科建设工程(PAPD);南京林业大学轻工与食品学院青年教师科研基金。

摘　　要：采用桨式转子流变仪测量并分析研究了漂白化学针叶木泡沫浆料的流变曲线及流变参数变化规律。结果表明,未起泡时,加入聚乙烯醇(PVA)的针叶木浆料为Herschel-Bulkley塑性稀化流体,其表观黏度大于普通浆料。起泡后,针叶木浆料流变曲线分为剪切变稀阶段和剪切增稠阶段。纤维质量浓度为1.5%、2.0%和2.5%时,针叶木泡沫浆料流变性能转折点对应的剪切速率分别约为120、150和190 s-1。PVA质量浓度对针叶木泡沫浆料的流变性能影响较小。针叶木泡沫浆料的质量浓度越高,其剪切应力和表观黏度越大。随着针叶木泡沫浆料含气率的提高,其剪切变稀阶段的黏滞系数K1呈线性递增,剪切增稠阶段的黏滞系数K2呈幂函数递减;而剪切变稀阶段的流动指数n1呈线性降低,剪切增稠阶段的n2与之变化规律相反。The rheological curves and rheological parameters of bleached chemical softwood foam-fiber suspension were measured by the rheometer with a propeller-type rotor.The results showed that the fiber suspension with polyvinyl alcohol(PVA)was Herschel-Bulkley plastic shear-thinning fluid when it was not foamed,but its apparent viscosity was higher than that of general fiber suspension.The rheological curves indicated two-stage rheological behavior of the foam-fiber suspension with PVA,shear thinning stage and shear thickening stage.The corresponding shear rate of each rheological turning points between the two stages were about 120,150,and 190 s^-1,respectively when the fiber mass concentration was 1.5%,2.0%,and 2.5%.The PVA content had little effect on the rheological property of foam-fiber suspension.The foam-fiber suspension with higher fiber mass concentration had higher shear stress and apparent viscosity.Increasing air content increased the viscosity coefficient K1 linearly in the shear thinning stage,but reduced viscosity coefficient K2 followed power-law trend in the shear thickening stage;decreased the flow index n1 linearly in the shear thinning stage,but increased low index n2 linearly in the shear thickening stage.

关 键 词：泡沫浆料 聚乙烯醇 表观黏度 黏滞系数 流动指数 

分 类 号：TS721[轻工技术与工程—制浆造纸工程] O373[理学—流体力学]