Method for preparing polymer of butene diacid

This invention relates to a preparation method for poly(butenedioic acid). Polymerization takes places in aqueous phase where there are monomers including one of several species of butenedioic acid and its derivatives, transition metal salts as catalysts and possibly hypophosphorous acid, phosphorous acid and their salts as well. It is initiated with the addition of guanyl isopropylazo hydrochloride and oxyol and the molecular weight of the polymers is over 800. Therefore, poly (butenedioic acid) with a high molecular weight can be prepared in this method and the common problems of low molecular weight and high molecular weight distribution that exist in current techniques can be effectively solved. And the consequent polymer product performs an active scale-inhibitory and corrosion-inhibitory effect and excellent properties of complex systems.