摘要 |
<p>A method is described for reducing hexavalent chromium in common cements and cement based materials comprising the addition, to said cements, of a suitable reducing agent embedded in a polymer matrix consisting of polyvinyl acetate (PVA), polyvinyl alcohol (PVOH), polyglycolic acid (PGA), polyglycolic acid/lactic acid copolymers (PGA/PLA), polyacrylic acid (PAA), maleic polyanhydride (PMA), acrylic or methacrylic acid/acrylic ester/styrene copolymers, acrylic or methacrylic acid/maleic anhydride copolymers, ethylene/maleic anhydride copolymers, polyester/maleic anhydride copolymers, ethylene oxide/polyethylene oxide copolymers.</p> |