Compositions for binding organic or inorganic fibers are described. The compositions may include an aqueous solution having a pH of about 4.5 or more. The aqueous solution may include a polycarboxy polymer that is about 10%, by wt., to 100%, by wt., of a butenedioic acid or butenedioic anhydride; and a polyol. The compositions can maintain a pH of about 5 or more after being cured into a thermoset plastic with the fibers. Processes for preparing a binder composition for organic or inorganic fibers are also described. The processes may include providing an aqueous solution of polycarboxylic acid polymers, where the polymers comprise about 10%, by wt., to 100%, by wt., of a butenedioic acid or butenedioic anhydride; adding a polyol to the aqueous solution; and maintaining the pH of the aqueous solution at about 5 or more.