New techniques for the quantitative determination of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine copolymers in aqueous solutions have been developed. The proposed spectrophotometric technique allows one to determine the copolymer concentration in dilute solutions (0.8 – 1.2 mg/ml) even in the presence of an interfering addition – merthiolate. The proposed refractometric technique is simpler and allows one to determine the copolymer concentration in concentrated solutions (>1 mass %).

The solubility in water has been investigated for copolymers of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine with various monomer ratios. Aqueous solutions of the copolymers have low critical mixing temperatures. The solubility of copolymers in water decreases with increasing pH and the concentration of 2-methyl-2-vinylpiridine monomer units. Correlation dependences for predicting the concentration and pH range of the homogeneous solution at the given mixing temperature are determined. The results are useful for the creation of officinal injection preparations based on copolymers of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine.

A copolymer of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine increases the phagocytic activity of macrophages. In addition, a tendency to increase in the fraction of phagocytic cells, phagocytic index, and index of phagocytosis completeness under the action of copolymer was observed.

Copolymers of N-vinylpyrrolidone and 2-methyl-5-vinyltetrazole with various ratios of monomer units have been synthesized by radical polymerization using the injection method. The parameters of copolymerization for these monomers were calculated by the Kelen – Tudos method ( r 1 = 14.34; r 2 = 0.06) for high degrees of conversion. Copolymers with the concentration of monomer units up to 70 ± 5 mol. % are soluble in water, non-toxic, and active as radioprotectors.

Copolymers of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine with various ratios of monomer units and molecular weights have been synthesized by radical copolymerization using injection method. The ratio of monomer units was determined by nonaqueos potentiometric titration and 13 С NMR methods. The viscosity-average molecular weight of copolymers containing 35 - 39 mol % of 2-methyl-5-vinylpyridine units is within 15.2 - 27.6 kDa. The copolymers with a content of 2-methyl-5-vinylpyridine units up to 75 + 5 mol % exhibit good solubility in water.