Alkaline synthesis of double co-oligomers of 2-propenylphenol and formaldehyde (synthons) was carried out at 92-950C, for 3 hours and ratio of 1:2.5 mol (their yield are 93% of theory)Interaction of maleic anhydride with the obtained olygomers at 800C in the presence of 0.5% benzoyl peroxide for 10 hours produced copolymers of a three-dimensional cross-linked structure (with a yield of 90%). By treating them with hot water, a sorbent was obtained to contain both propenyl and carboxylate fragments in the structure - active centers of chemisorption. The functional sorption properties of the copolymer were studied under static conditions, in model water systems. The influence of the pH of the medium, the concentration of uranyl ions and the exposure time on the degree of their sorption at room temperature were studied and it was found that the best results are achieved at pH 6 and for 24 hours (R=93%). Uranyl ions can be easily desorbed with mineral acid and the crosslinked copolymers can be reused.