亚洲AV成人片无码网站玉蒲团,男人10处有痣是富贵痣,AV亚洲欧洲日产国码无码苍井空,日韩午夜欧美精品一二三四区

產品展廳收藏該商鋪

您好 登錄 注冊

當前位置:
美國布魯克海文儀器公司>公司動態>Omni測量應用案例-2016-14

公司動態

Omni測量應用案例-2016-14

閱讀:207          發布時間:2016-5-26

文獻名: Rheology of cellulose nanofibrils in the presence of surfactants

作者: Nawal Quennouz,a   Sara M. Hashmi,a   Hong Sung Choi,b   Jin Woong Kimcd and    Chinedum O. Osujia  
a Department of Chemical and Environmental Engineering, Yale University, New Haven CT 06511, USA
b Shinsegae International Co. Ltd, Seoul, Republic of Korea
c Department of Applied Chemistry, Hanyang University, Ansan, Republic of Korea
d Department of Biono Technology, Hanyang University, Ansan, Republic of Korea


摘要:Cellulose nanofibrils (CNFs) present unique opportunities for rheology modification in complex fluids. Here we systematically consider the effect of ionic and non-ionic surfactants on the rheology of dilute CNF suspensions. Neat suspensions are transparent yield-stress fluids which display strong shear thinning and power-law dependence of modulus on concentration, G′ ∼ c2.1. Surfactant addition below a critical mass concentration cc produces an increase in the gel modulus with retention of optical clarity. Larger than critical concentrations induce significant fibril aggregation leading to the loss of suspension stability and optical clarity, and to aggregate sedimentation. The critical concentration was the lowest for a cationic surfactant (DTAB), cc ≈ 0.08%, while suspension stability was retained for non-ionic surfactants (Pluronic F68, TX100) at concentrations up to 8%. The anionic surfactant SDS led to a loss of stability at cc ≈ 1.6% whereas suspension stability was not compromised by anionic SLES up to 8%. Dynamic light scattering data are consistent with a scenario in which gel formation is driven by micelle–nanofibril bridging mediated by associative interactions of ethoxylated surfactant headgroups with the cellulose fibrils. This may explain the strong difference between the properties of SDS and SLES-modified suspensions. These results have implications for the use of CNFs as a rheology modifier in surfactant-containing systems.
 

收藏該商鋪

登錄 后再收藏

提示

您的留言已提交成功!我們將在第一時間回復您~

對比框

產品對比 產品對比 聯系電話 二維碼 意見反饋 在線交流

掃一掃訪問手機商鋪
010-62081908
在線留言