带相反电荷胶体颗粒混和悬浮体的流变学性能  

Rheological Properties of Mixed Suspensions Containing Oppositely Charged Colloidal Particles

作　　者：郭培志[1] 孙德军[1] 金志琳[1] 张春光[1] 

机构地区：[1]山东大学胶体与界面化学研究所,胶体与界面化学教育部重点实验室,济南250100

出　　处：《高等学校化学学报》2003年第6期1052-1055,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 0 0 430 0 2 );教育部科学技术研究重点项目 (批准号 :0 2 12 8);山东省自然科学基金 (批准号 :Y2 0 0 1B0 1)资助

摘　　要：研究了带相反电荷的粘土颗粒和 MMH(铝、镁混合金属氢氧化物 )颗粒形成的混和悬浮体的流变学性能 ,考察了盐对混合体系流变学性能的影响 .结果表明 ,当粘土质量分数为 1 %时 ,悬浮体为牛顿型流体 ;当质量分数升至 2 %时 ,悬浮体表现出固体的弹性响应 ;特定粘土含量的悬浮体中 ,随着 MMH量的增加 ,混合体系的屈服值和弹性模量亦增加 ,表明凝胶结构增强 .向混合体系中加入 Na Cl,弹性模量、屈服值和粘度等流变参数均降低 .与单组分粘土悬浮体或 MMH悬浮体相比 ,双组分混合体系的结构恢复很快 .The rheological properties of single-component clay dispersions and clay/MMH mixed dispersions containing oppositely charged colloidal particles have been investigated. As the clay concentration is increased, the clay suspensions develop from the newtonian form of flow behavior to a yielding type of response. At w(clay) is between 2%-4%, upon addition of MMH to clay dispersions, the magnitude of yield value and storage modulus increase monotonically, indicating enhanced gel strength. Adding NaCl to clay/MMH mixed suspensions causes the decrease of storage modulus, yield values and apparent viscosities. In the structural recovery measurements, the time dependence of viscoelastic properties of clay/MMH mixed dispersions shows only very small variations of the storage moduli over 3 h, in contrast to unusual thixotropic properties of aqueous single-component dispersions of laponite or MMH. The above results are interpreted based on attractive electrostatic interactions between clay and MMH particles due to their opposite charges, similar to the edge(+)/face(-) interactions in single-component clay dispersions under a low pH value.

关 键 词：相反电荷胶体颗粒 混和悬浮体 流变学性能 粘土颗粒 铝镁混合金属氢氧化物 盐 

分 类 号：O648.12[理学—物理化学]