Preamble:
Emulsion polymers are procured through the process of emulsion polymerization, which is a kind of radical polymerization. Emulsion polymerization imposes various advantages. They furnish polymers that are high in their molecular weight. However, in bulk and free-radical polymerization methodologies, a balance is achieved between molecular weight and the rate of polymerization.
Merits and demerits of emulsion polymerization:
The viscosity of the reaction medium does not depend on molecular weight and it remains near to the viscosity of water as the produced polymer molecules are contained within the particles. Fast polymerization rates are made possible as unceasing water phase is an exceptional conductor of heat. Besides, there is no loss of temperature control whatsoever. The procured end products need not be modified as they will definitely suit the requirements. However, there is a major drawback in emulsion polymerization wherein the conversion of monomer to polymer could result in considerable chain transfer to polymer.
Process of emulsion polymerization:
Emulsion polymerization has been carried out in various process methodologies. These implicate continuous, batch and semi-batch processes. The choice of process relies upon the properties desired for the end polymer and financial requirements. Synthetic rubbers have been rampantly manufactured through continuous processing. Batch processes entail polymerization with breaks. Early styrene -butadiene rubbers are manufactured in this methodology. Emulsion polymerization typically incorporates colloidal stability a factor for efficient functioning. Hence colloidal properties like viscosity, particle size and particle distribution are ponderously necessary to enhance the performance rate of polymer products sold as dispersion.
Ideal ingredients for emulsion polymerization:
There are various ingredients involved in the polymerization process of emulsion polymers. This generally encompasses monomers, comonomers, initiators, non-surfactant stabilizers, surfactants, and other minor ingredients like buffering agents, inert salts, and chain transfer agents. There are various conditions to be fulfilled in order to become the ideal ingredient option for the process of emulsion polymerization. These conditions generally revolve around the solubility and reactive nature of chemical compounds.
Applications:
Emulsion polymers have been widely used in various industries. They are used in paints and coatings so as to enhance heat sensitivity, self-repairing abilities and the quality of the color. Emulsion polymers are pervasive in this industry due to the soaring demand for high quality paints. They are also employed in permanent and removable adhesives. Besides, adhesives play a significant role in various industries implicating foot wear, packaging and house hold furnishings. Consequently, the demand for emulsion polymers in these industries has increased to a great extent. Furthermore, emulsion polymers are also being employed in the adhesives that are used in automotive industries.