Orthokinetic heteroaggregation with nanoparticles: Effect of particle size ratio on aggregate properties
Orthokinetic heteroaggregation with nanoparticles: Effect of particle size ratio on aggregate properties
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纳米颗粒的正交运动异质聚集：粒径比对聚集体特性的影响
DOI：
10.1016/j.colsurfa.2008.05.030
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
G. Jameson
中科院分区：
文献类型：
--
作者：
P. Yates;G. Franks;G. Jameson
本研究采用了三种不同的聚合方法：加入HMW聚合物，加入二氧化硅颗粒（直径分别为4.3、105和285nm），将悬浮液的pH调节为9。用这三种方法絮凝了稳定的氧化铝分散体（310nm），发现每种方法都能使氧化铝聚集在一起，使聚集物的形成和破坏达到平衡。聚合体的平衡尺寸从大到小依次为：HMW Polymer、MP3040、STZL、STXS (285nm、105nm、4.3nm)， pH值为9。光散射模拟显示了第二种粒子（二氧化硅）对散射强度与波矢量关系（I与Q）的影响。从光散射数据中获得分形关系仍然是可行的，即使有两粒子不对称系统所引起的复杂性。随着粒径比（0.014,0.339,0.92）的增加，分形维数略有增加（2.04,2.06,2.19），表明相似粒径的颗粒之间的相互作用更强。聚集体的强度由强到弱依次为：HMW Polymer， 285nm, 105nm, 4.3nm， pH为9。粒子-粒子相互作用能计算表明，较大的二氧化硅具有最强的相互作用势。粒子间的相互作用能随着二氧化硅颗粒的减小而减弱。
Three different aggregation methods were employed in this work: the addition of HMW polymer, the addition of silica particles (4.3, 105 and 285nm diameter) and adjustment of suspension pH to 9. Stable alumina dispersions (310nm) were flocculated using these three methods and each method was found to aggregate the alumina causing equilibrium between formation and destruction of aggregates. The equilibrium size of the aggregates (from largest to smallest) was found to follow the order: HMW Polymer, MP3040, STZL, STXS (285nm, 105nm, 4.3nm) and pH 9. The use of light scattering simulations showed the effect of a second particle species (silica) on the scattering intensity versus wave vector relationship (I versus Q). It was still feasible to obtain a fractal relationship from the light scattering data, even with the complications arising from a two particle asymmetrical system. The fractal dimension increased slightly (2.04, 2.06, 2.19) with an increase in particle size ratio (0.014, 0.339, 0.92) suggesting stronger particle interactions between particles of similar size. The strength of the aggregates was rated from strongest to weakest: HMW Polymer, 285nm, 105nm, 4.3nm and pH 9. Particle–particle interaction energy calculations showed the strongest interaction potential for the larger silica. The particle–particle interaction energy was found to be weaker the smaller the silica particles become.