EFFICIENT METHOD FOR THE EMULSION POLYMERIZATION OF STYRENE MONOMER IN SUPERCRITICAL CARBON DIOXIDE USING (TRIFLUOROMETHYL) UNDECA-FLUOROCYCLOHEXANE STABILIZER

摘要

Successful emulsion polymerization of styrene monomers in supercritical carbon dioxide (sc-C02) using (trifluoromethyl)undecafluorocyclohexane (C7F 14) as a stabilizer and azobisisobutyronitrile (AIBN) as initiator. The emulsion polymerization was carried out using different percentage of stabilizers (0.2%-10%), different initiator concentrations (0.1%-0.5%) and different pressures (2100-2500 psi). The polymers were characterized by GPC, SEM and TGA. The influence of different process parameters (stabilizer concentration, initiator concentration and pressure of CO2) on conversion, molecular weight, particle size and polydispersity index was elaborately studied. Molecular weight of the polymer is in the range of 32,000 to 55,000g/mol, polydispersity is 1.43-2.33 and particle size in the range of 0.15/um- 1.0/um.