Composite polymer particles via concentrated emulsification

A concentrated emulsification technique was used to make fine emulsions of polymer/monomer solutions. Subsequent polymerisation of the diluted concentrated emulsions produced polymer composite particles. Highly concentrated oil/water emulsions were made using an unsaturated polyester (UP) solution in a vinyl monomer such as styrene as the oil phase. As the volume fraction of the oil phase increased, the mean drop size first increased but then decreased significantly. Subsequent dilution of the concentrated emulsions did not affect the mean drop size significantly. Increasing the monomer concentration in the oil phase reduced the drop size but resulted in larger polymer particles after polymerisation. Increasing the temperature and initiator concentration increased the rate of polymerisation as expected. With increasing the temperature and surfactant concentration smaller polymer particles were obtained.