In recent years poly(viny1ene glycol), poly(hydroxymethy1ene ether)s, or poly( 1,2-dialkoxy-ethy1ene)s have been synthesized' -'). The methods of their preparation by cationic polymerization of 1,2-dialkoxyethylenes, particularly, cis-I ,2-dimethoxyethylene and p-dioxene (2,3-dihydro-l,4-dioxine), have already been d e~c r i b e d~.~) .Poly(l,2-dimethoxyethylene) (1) exhibits an exceptional universal solubility in various organic solvents (with the exception of saturated hydrocarbons) and in water. The behaviour of 1 in water is of particular interest: on heating it undergoes a conformational random coil-globule transition5'.The method of polarized luminescence was used to demonstrate that I and poly(l,4-dioxane-2,3-diyl) [poly@-dioxene)] (2), synthesized by us, form polymer complexes (PC) with poly(methacrylic acid) (PMAA) in water. Tab. 1 gives the values of relaxation times, T,, characterizing the intramolecular mobility (IMM) of the polymer chains of PMAA, 1, and 2 in aqueous solutions. When PMAA (with the degree of neutralization a = 0) is introduced into the aqueous solution of l (or 2), the relaxation times, T,, for l (2) and PMAA macromolecules increase. This indicates that a PC is f~r m e d~-~) .The data in Tab. 1 show that in the formation of a PC, relaxation times characterising the IMM of macromolecules increase to the same value for each component of the PC (a polymeric ether and a polymeric acid), the coincidence of relaxation parameters of the interacting macromolecules being a criterion for the formation of a stoichiometric PC7.91.Data in Tab. 1 show also that hydrophobic interactions of nonpolar methyl groups of PMMA with nonpolar groups of the polymers 1 and 2 play a great part in the formation of a PC. The transition from 1 with two methyl groups in each monomeric unit to 2 with methylene groups, greatly decreases the value of T, for macromolecules comprising PC. This may be caused by a decrease in the duration of interchain contacts.When the carboxylic groups of PMAA are ionized, the PC formed by 1 or 2 with PMAA are destroyed. At a = 0,3, relaxation times T , for macromolecules that comprised PC at a = 0, coincide with those for single 1, 2, and PMAA macromolecules at a=O,3 (third column in Tab. 1). The Table shows that the dissociation of (2-PMAA)-complex occurs at lower degrees of neutralization of PMAA than that of the (I-PMAA)-complex (see the values for I* and 2* in PC at a = 0,2 and a = 0,3).