Mixtures containing polyvinyl alcohol (PVA) and methylcellulose (MC) were obtained and used to synthesize hydrogels in various ratios of components. The swelling kinetics of the resulting hydrogels were studied, revealing that the equilibrium swelling degree in artificial saliva is nearly twice as high as in water. It was found that increasing the volumetric content of PVA in the mixture leads to a higher swelling degree. The kinetics of active pharmaceutical ingredient (API) sorption and release from the hydrogels were also investigated. It was demonstrated that hydrogels with a higher PVA content exhibit greater sorption capacity; however, the release of the API from such samples occurs at a slower rate. For the first time, the mucoadhesive properties of PVA-MC-based hydrogels were studied. It was established that the PVA-MC hydrogel with a ratio of 6:4 vol.% remained on the surface of the porcine cheek mucosa for two days, the 5.5:4.5 vol.% sample detached after 24 h, and the 5:5 vol.% sample adhered for approximately 10 h. These findings confirm the mucoadhesive potential of the hydrogels and their suitability for buccal drug delivery forms. The synthesized PVA-MC hydrogels are promising for applications in medicine and pharmacology.

In this study, polymer films based on polyvinyl alcohol (PVA), modified starch, and acrylic acid (AA) were synthesized and characterized. For the first time, this work investigates the synergistic effect of incorporating AA into films based on PVA and preirradiated starch. Unlike conventional approaches that rely on simple blending of PVA and starch, the use of AA as a functional monomer enables the formation of a chemically cross‐linked structure, where the carboxyl groups of AA establish additional hydrogen and covalent bonds with the hydroxyl groups of PVA and starch, as confirmed by FTIR spectroscopy. Furthermore, this study employs starch that has been pretreated with electron beam irradiation, which enhances component compatibility and improves the mechanical and thermal properties of the films. A comprehensive analysis of the main physicochemical properties of the films showed that increasing the AA content led to a rise in gel fraction yield from 67.4% to 86.2%, indicating a denser cross‐linked polymer network. Thermogravimetric analysis demonstrated improved thermal stability with increasing AA content, with the decomposition temperature reaching up to 450°C and total mass loss reduced to 50%. Mechanical testing revealed a significant enhancement in strength and elasticity: The tensile strength increased from 300 to 500 kPa, and the Young’s modulus increased from 0.3897 to 0.5514 kPa. The obtained results suggest that PVA/starch/AA films hold great potential as a promising material for biodegradable packaging applications.

Study of the physico-chemical properties of novel water-soluble copolymers of cationic type based on N-isopropylacrylamide

The novel cationic hydrogels based on N-isopropylacrylamide (NIPAAm) and N-(2-vinyloxyethyl)-N-(2-cyanoethyl) amine (VOECEA) were synthesized for the first time by radical copolymerization. The composition of copolymers were determined by using IR spectroscopy.

According to results of the thermal analysis and infra red spectroscopic measurements, synthetic amorphous orthophosphate of calcium-magnesium with the nuclear relation Ca/Mg/P≈2/1/2 containing in the structure about 80% of water on air at the room temperature loses almost all the moisture. Dehydration proceeds in four stages with formation of the intermediate phases containing a different amount of water and chemical bonds differing by bonding state of P-O. The remaining moisture is lost at heating in three stages. Thus phosphate changes at the level of chemical bonds.

Influence of ionic strength on swelling degree of polymeric HEA-MMA hydrogels was investigated. It is shown that contraction of HEA-MMA hydrogels can be reached by variation of ionic strength and structure of initial monomeric mix.