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Polymer

A substance composed of giant molecules that have been formed by the union of a number of simple molecules with one another. The number that unite to form a polymer molecule varies from two to hundreds or thousands. The simple molecules that undergo such a change are known as monomers, and their union is called polymerization. The monomer molecules may be all alike, or there may be two or more varieties of monomer involved in the formation of a single polymer. Ethylene molecules can be united with themselves to form polyethylene resin which is a monopolymer. SBR synthetic rubber is a copolymer, since two different kinds of monomer (styrene and butadiene) are required. A polymer formed from three monomers is a terpolymer. The most important polymers in order of volume used are polyethylene, polyvinyl and polystyrene.

Viscosity: From the above discussion it is obvious that there can be a wide range of properties of a polymer. Records show that a viscosity range of 220 to 22,000 cPs. would cover most polymers pumped. Sp. Gr. is a function of the particular polymer.

Remarks: In addition to the many chemical names for polymers, there are many trade names used by manufacturers to identify their specific polymers.

 Pump Notes: Cast iron construction is usually satisfactory but stainless steel may also be required. Elastomer recommendation depends on the particular polymer.