![]() When surfactant concentration exceeds critical micelle concentration (CMC) it aggregate in the form of spherical micelles, so surface tension at the surface decrease, as a result hydrophobic monomers enter in to the vicinity of micelle and reaction continue until all monomer droplets are exhausted and micelle containing monomers increase in size. The dispersion medium is water in which hydrophobic monomers is emulsified by surface-active agents (surfactant). The main components of emulsion polymerization media involve monomer(s), dispersing medium, emulsifier, and water-soluble initiator. ![]() Components of heterogeneous emulsion polymerization Many articles discuss different types of emulsion polymerization found in literature. Miniemulsion, microemulsion and conventional emulsion polymerizations show quite different particle nucleation and growth mechanisms and kinetics. (3) Mini emulsion polymerization involves systems with monomer droplets in water with much smaller droplets than in emulsion polymerization and characterized by monomer droplet =50–1000 nm, surfactant concentration CMC, polymer particles = 10–50 nm, water-soluble initiator are commonly used. These two polymerization types known as oil-in-water (o/w) and water-in-oil (w/o) emulsions. (2) Inverse emulsion polymerization, where organic solvents of very low polarity as paraffin or xylene used as a polymerization media to emulsify hydrophilic monomers, then initiation proceed with the aid of hydrophobic initiator. Systems of emulsion polymerization involve (1) conventional emulsion polymerization, in which a hydrophobic monomer emulsified in water and polymerization initiated with a water-soluble initiator. ![]() Aside from other polymerization techniques, emulsion polymerization affords increasing molecular weight of the formed latexes through decreasing polymerization rate by either decreasing initiator concentration or lowering reaction temperature. Emulsion polymerization is a rather complex process because nucleation, growth and stabilization of polymer particles are controlled by the free radical polymerization mechanisms in combination with various colloidal phenomena. These emulsion polymers find a wide range of applications such as synthetic rubbers, thermoplastics, coatings, adhesives, binders, rheological modifiers, plastic pigments. Typical polymerization monomers involve vinyl monomers of the structure (CH 2=CH-). 2,2-azobisisobutyronitrile (AIBN)) in the presence of stabilizer which may be ionic, nonionic or protective colloid to disperse hydrophobic monomer through aqueous solution. potassium persulfate (K 2S 2O 8) or an oil-soluble initiator (e.g. Controlled radical polymerisation is used in aiding encapsulation of inorganic particles like pigment particles and clay platelets.Emulsion polymerization is a unique process involves emulsification of hydrophobic monomers by oil-in water emulsifier, then reaction initiation with either a water soluble initiator (e.g. Another area that is rapidly progressing is the application of controlled radical polymerisation in emulsion polymerization. The second edition of this book includes a new chapter on morphology of latex particles, a rapidly progressing area where modelling the thermodynamic and kinetic aspects of phase separation and morphology has developed into a mature and powerful tool to predict and control morphology of latex particles. By carefully explaining the principles of the reaction, based on well-designed experimental investigation, the book explains how the principles relate to practical application. For those working in industry, coupling theory with everyday practice can be difficult. Summary: "Chemistry and Technology of Emulsion Polymerisation 2e provides a practical and intuitive explanation of emulsion polymerization, in combination with both conventional and controlled radical polymerization.
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