Investigation of the Effects of Suspension Agents on Particle Size Distribution in Suspension Polymerization of Styrene

Document Type : Research Article


1 Tabriz Petrochemical Company (T.P.C), Tabriz, I.R. IRAN

2 Iranian Academic Center for Education, Culture and Research (ACECR), Amirkabir University of Technology Branch, Tehran, I.R. IRAN

3 Islamic Azad University, North Tehran Branch, Tehran, I.R. IRAN


Suspension polymerization of styrene is an important way to produce polystyrene and expandable polystyrene. In this process, water is used as continues aqueous phase and styrene with additives like initiators are dispersed by agitator. Organic and inorganic stabilizers are used alone or together to stabilize suspension. Viscosity of monomer droplet increases as conversion increases during polymerization. Mean particle size and its distribution of polymer particles are key parameters that should be controlled. We used TCP, HEC and PVA to control these parameters in pilot scale reactor in Tabriz petrochemical complex. This research shows that, we should use more TCP than PVA to produce commercial size of EPS. HEC can't stabilize dispersion. But when we use suspension agents together, HEC and TCP show great results. The influence of HEC on particle size distribution is more than PVA.  There is no pollution inside reactor when we use TCP. But it is necessary to use optimum amount of PVA to produce less pollution and more commercial size of EPS.

Main Subjects

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