SYNTHETIC RESINS AND POLYMERS

Isophorone [14.268], [14.269] is an unsaturated cyclic ketone. It consists of a-isophorone [78-59-1] (3,5,5-trimethyl-2-cyclohexen-l-one), which contains about 1-3% of the isomer P-isophorone [471-01-2] (3,5,5-trimethyl-3-cyclohexen-l-one). Isophorone is a stable, water-white liquid with a mild odor that is miscible in all proportions with organic solvents. It dissolves many natural and synthetic resins and polymers, such as poly(vinyl chloride) and vinyl chloride copolymers, poly(vinyI acetate), polyacrylates, polymethacrylates, polystyrene, chlorinated rubber, alkyd resins, saturated and unsaturated polyesters, epoxy resins, cellulose nitrate, cellulose ethers and esters, damar resin (dewaxed), kauri, waxes, fats, oils, phenol-, melamine-, and urea-formaldehyde resins, as well as plant protection agents. However, isophorone does not dissolve polyethylene, polypropylene, polyamides. 

As discussed in the chapter on solvent power, most concepts are related historically to paint application, either as diluents or solvents for natural binders, synthetic resins and polymers. At first the requirements tended to be rather low, both in solvent power and sophistication. However, with the broadening of the spectrum of binders and application techniques the criteria for solvent selection became sharper and the formulations more complex. 

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