The copolymerization reactions of allyl- and vinyl ether of salicylic acid with maleic anhydride (MA) have been researched. It was shown that with transferring charge copolymer monomer pairs make complex and these complexes form rotational structure macromolecules with entering polymerization reaction easily. Equilibrium constant of complex among monomer pairs was defined with the help of PMR spectrums: for Alasp …MA couple Kc=0.097 and for Vasp…MA Kc=0.028. Via Chromotographic method – Jaaks equation relative activities of monomers have been identified. For Alasp–MA comonomer is г1=0.022, г2=0.038 and for Vasp– MA comonomers г1=0.036, г2=0.028. Being close to zero of relative activities of monomer in both case in copolymerization reactions prove that, those monomer pairs are inclined to copolymerization. The relativity of monomer pairs and the influence to the reaction of the concentration of monomer mixture in the copolymerization reactions of Vasp and MA is studied. The nature of curves is proved that the copolmerization reactions occurs by ²mixture² mechanizm by the presence of free monomers and monomer complex.