علوم و تکنولوژی پلیمر (Dec 2010)
The Effects of Temperature, Initiator and Stabilizer on Polymer Particle Size in Suspension Polymerization of Styrene
Abstract
In suspension polymerization, particle size distribution of polymer is the outcome of dynamic equilibrium between the break up and coalescence phenomena. The rates of break up and coalescence and consequently polymerization stability depend on several parameters, the most important of which are type and concentration of stabilizer. In this study, the effects of type and concentration of stabilizer, concentration of initiator and temperature on the average particle size and its distribution in suspension polymerization of styrene were experimentally studied. The results showed that poly-meric stabilizers, polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), are more effective than tricalcium phosphate (TCP) as an inorganic stabilizer in reducing coalescence and achieving narrower particle size distribution.By increasing the stabilizer concentration, average particle size was reduced, while by increasing the initiator concentration, the average particle size and its distribution increased. Lowering polymerization temperature led to small-er average particle size with its narrower distribution.
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