Investigation of Colorless and Water-Based Concrete Curing Compounds

摘要

Eleven concrete curing compounds designated as colorless and two compounds designated as water-based were evaluated for their suitability for curing of concrete and for their lack of color. All of the compounds met present specification requirements for sprayability, drying time, and flash point. Only ten of the materials met the moisture-retention requirements. The three materials that failed the moisture test were one colorless type (styrene-acrylate resin) and both water-based compounds. Infrared analysis revealed that the 11 colorless materials represent five different chemical classes as follows: four chlorinated rubbers, two modified styrene-butadienes, one phthalic alkyd, three carboxylated hydrocarbons, and one styrene-acrylate. Both water-based materials were identified as sodium silicate liquids. Upon being subjected to alternate cycles of rainfall and ultraviolet radiation in the weatherometer, some of the coated surfaces continued to lighten and the curing compounds washed off, while some became mottled and unattractive. There appeared to be no correlation between original color of the curing compound and color of the coated mortar surfaces either before or after exposure to controlled conditions. (Author)