STRUCTURAL PARAMETERS OF SPATIALLY CROSS-LINKED COPOLYMERS OF POLYETHYLENE GLYCOL MALEATE AND ACRYLIC ACID

Abstract

Abstract. Introduction. The development of polymer binders for construction and composite materials requires purposeful control over the structure of spatially cross-linked polymer networks, since the internal structural parameters largely determine the mechanical, sorption, and performance characteristics of materials. In this context, the quantitative evaluation of crosslink density and the number of junctions in polymer networks as a function of system composition represents an important scientific task. Methodology. In this study, spatially cross-linked copolymers based on polyethylene glycol maleate modified with acrylic acid were synthesized by a “cold” radical curing method at various mass ratios of the components. The structure of the obtained materials was confirmed by Fourier transform infrared (FTIR) spectroscopy. Quantitative assessment of the structural parameters of the polymer network was performed using equilibrium swelling data of the copolymers in water. The crosslink density, number of network junctions, and average molecular weight between junctions were calculated using the Flory–Rehner equation. Results of the study. It was established that an increase in the polyester component content in the investigated systems leads to a decrease in the swelling degree and to the formation of a denser spatially cross-linked structure, characterized by an increase in crosslink density and a reduction in the molecular weight between network junctions. The obtained results demonstrate the possibility of purposeful control over the structural parameters and properties of polyester binders by varying the system composition, thereby opening prospects for their application in construction and composite materials.