Polymerization of methylphenylphosphinic acid with zinc oxide has been investigated in aqueous media. Two species of polymer were obtained at the same time. One is crystalline

the other membranous (amorphous).They are allotropes. Using Onsager's equation

it has been shown that the soluble part of the polymer are in the form of ionic Zn++

MePhPO2- in aqueous solution

and so hydrolysis of this kind of polymers seems to be the process of dissolution and recrystallization in aqua.