EPDM rubber was not available in liquid form until relatively recently so Liquid Neoprene rubber became the material of choice for protecting concrete against both fresh and salt water. The Liquid Neoprene products are simple solvent solutions or water based emulsions and therefore have low solids content and relatively low molecular weights. These limitations made multiple coat applications necessary and required top coating with other polymers to prevent ultra violet degradation.
The development of Liquid EPDM Rubber resulted in a high solids, two components chemically reactive product capable of polymerizing at ambient temperatures( 55 F ( 13 C) and higher). This product can be applied at a 30 mil dry film (.76 mm) in a single application because of the high solids content. Its chemical cure feature then results in a high molecular weight film with protective and performance properties exceeding those of liquid applied Neoprene films.
EPDM Liquid Rubber can withstand boiling water or live steam and is inherently UV and ozone stable. The product is safer to use because of its higher flash point and the two component packaging permits extended storage at higher temperatures than liquid Neoprene. The non polar characteristic of the EPDM also gives it advantages over Neoprene in saltwater environments as well as better resistance to cathodic disbondment.
EPDM rubber has poor resistance to oils, fats, waxes and aliphatic solvents but possesses very good resistance to ketone solvents, alcohols, polar compounds, Salts, most acids up to 50 % concentration, alkalies and water.
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