کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
609442 880623 2010 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Leveling of thin films of colloidal suspensions
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Leveling of thin films of colloidal suspensions
چکیده انگلیسی

We present an analysis of leveling in thin films of colloidal suspensions. The colloidal particles are assumed to be much smaller than the film thickness and influence the film rheology through a concentration-dependent viscosity and bulk diffusivity. A system of coupled nonlinear partial differential equations based on lubrication theory is used to describe the film height and the particle concentrations in the bulk and at the film surface. Linear stability analysis is applied to develop expressions for leveling rates in a number of limiting cases. It is found that for soluble particles, there exist regimes where increasing the Marangoni number slows down leveling at both short and long times, in contrast to the case of insoluble particles. Nonlinear simulations show that the linear theory accurately predicts leveling times even for large amplitude disturbances, and that the presence of a concentration-dependent viscosity and bulk diffusivity speed up leveling. The results of this work should be useful for estimating leveling rates in coatings laden with colloidal particles, and also in coatings containing soluble surfactant.

Convection, diffusion, adsorption, and desorption of colloidal particles all infuence the leveling of thin liquid flms.Figure optionsDownload high-quality image (78 K)Download as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Colloid and Interface Science - Volume 343, Issue 1, 1 March 2010, Pages 306–313
نویسندگان
, , ,