| 초록 |
Emulsion polymerization of styrene in the presence of molecular iodine has been successfully performed using various initiators such as KPS, APS, NaPS under argon atmospheres at 80oC for 7 hr in the absence of light. The effects of the iodine concentration and molar ratio between initiator and iodine on the molecular weight of polystyrene were studied. As the iodine concentration increased from 0.45 to 0.75 mmol under the fixed concentration of initiator at 2.25mmol, the weight average molecular weight and reaction rate decreased with increasing Iodine content but the particle size decreased . In addition, as the ratio of reaction scale increased from 150ml to 1500ml reaction rate and particle size are increased but molecular weight is little bit increased. As the result, we figure it out that Iodine concentration can be important factor for control of molecular weight with per sulfate initiators in emulsion polymerization |
