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Sodium polyacrylate also named acrylic sodium salt polymer or simply ASAP (repeating unit: -CH2-CH(CO2Na)- ) is a crosslinked acrylic acid polymer sodium salt, invented by Robert Niles Bashaw, Bobby Leroy Atkins and Billy Gene Harper in the Basic Research Laboratory of the Dow Chemical Company. Polymers were produced which absorbed up to 1,000 times their weight in distilled water (gel capacity) and are called polyelectrolytes. These polymers are referred to as "Super Absorbents" and "Water Crystals". (wikipedia)