کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1379933 1500662 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The study on the dispersing mechanism of starch sulfonate as a water-reducing agent for cement
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
The study on the dispersing mechanism of starch sulfonate as a water-reducing agent for cement
چکیده انگلیسی

Many water-reducing agents are environmentally unacceptable and non-renewable. As environment-friendly and renewable organic resource, starch has been used to synthesize starch sulfonate (SS). In this paper, the adsorption characteristics of SS on Portland cement particles were investigated by measuring zeta potentials, X-ray photo spectroscopy and UV–visible adsorption and its effects on the fluidity of cement paste were studied in comparison with traditional naphthalene sulfonated formaldehyde condensates (FDN) whose dispersion ability mainly depends on electrostatic repulsive forces. The results indicate the adsorption isotherm of SS conforms to Langmuir-type adsorption and the adsorption conformation of SS is dendritic due to its molecular structure. The adsorption layer of SS is much thicker than FDN. The dispersion capacity of SS mainly comes from steric hindrance effects rather than electrostatic repulsive forces. The dispersions stabilized by steric hindrance have better fluidity at lower adsorption amount and higher stability than those stabilized by electrostatic repulsive forces.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 70, Issue 4, 1 November 2007, Pages 363–368
نویسندگان
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