Synthesis of synthetic water soluble polymers

The manufacture of synthetic water soluble polymers on an industrial scale is often conducted on high capacity facilities that have an annual output of 20,000 tonnes or greater. This manufacture has to balance a number of important objectives that include product properties, cost effective performance and customer needs. This has been succinctly summarised as the ability to manufacture a product with specified physical and chemical properties at a desired production rate [7]. 

For synthetic water soluble polymers, this capability can be considered as the ability to deliver a product that meets the performance needs of the customer that is provided in the most acceptable physical form having considered issues of transportation, handling, storage stability and polymer make-up and dosing. 

These acrylic monomers are reactive and can be polymerised in various forms in both one-phase and two-phase systems (e.g. solution, emulsion etc.). 

Typical synthetic water soluble flocculants are polyelectrolytes that are most often based upon copolymers of acrylamide or substituted derivatives. Acrylamide monomer is obtained industrially by the catalytic hydration of acrylonitrile and occurs in both crystaUine form and in aqueous solution. The 50% aqueous form is the preferred form for polymerisation systems in which water can be tolerated. Acrylamide has a very fast propagation rate and a high exothermic heat of polymerisation. 

Acrylic acid is the most widely used anionic water soluble monomer. Anionic copolymers of acrylamide may be prepared by homopolymerisation of acrylamide followed by hydrolysis to the required extent, by addition of an appropriate amount of alkali, to produce an anionic polymer containing both amide and carboxyl groups. In practice however, monomer mixtures of acrylamide with acrylic acid or one of its alkali metals salts are 

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