A Generalized Refractive Index Equation for Estimating the Average Particle Size in Colloidal Suspensions
A Generalized Refractive Index Equation for Estimating the Average Particle Size in Colloidal Suspensions
复制标题
用于估计胶体悬浮液中平均粒径的广义折射率方程
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
M. Mohammadi
中科院分区：
文献类型：
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作者：
M. Mohammadi
本文提出了一种快速表征分散体和乳液微观结构的技术。该技术依赖于一个广义方程，该方程将胶体悬浮液的折射率与其分散相的尺寸和体积浓度相关联。从测量的液体的折射率，可以使用该等式计算体积加权平均粒径D 4，3。最近商业化的高精度临界角数字折射仪能够精确测量混浊分散体的折射率，因此使该技术成为一种可行的快速测量颗粒大小而无需稀释的方法。测量纯分散体的折射率的可能性意味着计算的D 4，3反映了"真实的"粒度，其可以包括聚集或絮凝的颗粒结构。在絮凝的样品中，折射率法读取絮凝物的尺寸，其与系统的流变学和相分离行为更好地相关。胶乳分散体、乳液和脂质体分散体的施胶结果与不存在絮凝的常规方法相比很好。
ABSTRACT This paper proposes a rapid technique for characterizing the microstructure of dispersions and emulsions. The technique relies on a generalized equation that relates the refractive index of a colloidal suspension to the size and volume concentration of its dispersed phase. From the measured refractive index of the liquid one can calculate the volume-weighted average particle size, D 4,3, using this equation. Recent commercial high-precision critical-angle digital refractometers enable the accurate measurement of the refractive index for turbid dispersions and hence making this technique a viable rapid method for particle sizing without dilution. The possibility of measuring the refractive index of neat dispersions means that the calculated D 4,3 reflects the “real” particle size which could include clustered or flocculated particle structures. In flocculated samples the refractive index method reads the floc size which correlates better with the rheological and phase separation behavior of the system. The sizing results for latex dispersions, emulsions, and liposomal dispersions compare well with conventional methods in the absence of flocculation.