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In polymer chemistry, emulsion polymerization is a type of radical polymerization that usually starts with an emulsion incorporating water, monomers, and surfactants.The most common type of emulsion polymerization is an oil-in-water emulsion, in which droplets of monomer (the oil) are emulsified (with surfactants) in a continuous phase of water.
Synthetic polymers began replacing other chemical binders for soil stabilization in agriculture in the late 20th century. [1] Compared to traditional chemical binders, polymer soil additives can achieve the same amount of strengthening at much lower concentrations – for example, mixtures of 0.5-1% of various biopolymers have strength levels that match or exceed those of 10% cement mixtures ...
For example, for the polymerization of ethylene, 93.6 kJ of energy are released per mole of monomer. [8] The manner in which polymerization is conducted is a highly evolved technology. Methods include emulsion polymerization, solution polymerization, suspension polymerization, and precipitation polymerization.
Low-energy methods - For the low-energy methods, the water-in-oil emulsion is usually prepared and then transformed into an oil-in-water miniemulsion by changing either composition or temperature. The water-in-oil emulsion is diluted dropwise with water to an inversion point or gradually cooled to a phase inversion temperature.
Solution polymerization is a method of industrial polymerization. In this procedure, a monomer is dissolved in a non-reactive solvent that contains a catalyst or initiator. The reaction results in a polymer which is also soluble in the chosen solvent. Heat released by the reaction is absorbed by the solvent, reducing the reaction rate.
Suspension polymerization is divided into two main types, depending on the morphology of the particles that result. In bead polymerization, the polymer is soluble in its monomer and the result is a smooth, translucent bead. In powder polymerization, the polymer is not soluble in its monomer and the resultant bead will be porous and irregular. [5]
Compared to previous methods of capsule synthesis, interfacial polymerization is an easily modified synthesis that results in capsules with a wide range of properties and functionalities. [ 1 ] [ 2 ] Once synthesized, the capsules can enclose drugs, [ 6 ] quantum dots , [ 1 ] and other nanoparticles, to list a few examples.
A Ramsden emulsion, sometimes named Pickering emulsion, is an emulsion that is stabilized by solid particles (for example colloidal silica) which adsorb onto the interface between the water and oil phases. Typically, the emulsions are either water-in-oil or oil-in-water emulsions, but other more complex systems such as water-in-water, oil-in ...