Tesis

The free radical copolymerization of acrylamide with different monomers has been investigated in inverse emulsion/suspension polymerizations. Different formulations and process parameters were performed to evaluate its influence in the obtained polymer properties and polymerization process control.The type and the percentage of the charge, the percentage of the actives, the dispersant system and the addition of a crosslinker agent were the emulsion/suspension formulation parameters studied. In reference to the polymerization process, the initiator type and its concentration as well as the pre-emulsification and the emulsification time and the temperature conditions during the polymerization were the varied process parameters.The residual monomer concentration and the conversion degree were determined by High Pressure Liquid Chromatography measurements, the reological behaviour of the emulsions during the polymerization were estimated by shear viscosity measurements, the molecular weight characteristics were estimated by intrinsic viscosity measurements. The particle size and the solution properties of the emulsions were estimated by Dynamic Light Scattering and Inverse Viscosity test respectively.It was found that the quality of the primary emulsion, that means the appropriate values for the Hydrophilic-Lipophilic Balance and the particle size, is the main factor to make better the heat removal allowing to develop the polymerization reaction under isothermal conditions.The polyelectrolites obtained were tested in practical application as flocculants for municipal waste-water treatment. In most of the cases the obtained polymer reach better performance than the commercial flocculants currently used.