A. I. Emel’yanov

Functional Polymer Nanocomposites Containing Triazole and Carboxyl Groups

New water-soluble functional polymer nanocomposites with nanoparticles of metallic silver in a matrix of 1-vinyl-1,2,4-triazole copolymers with crotonic acid have been synthesized. The resulting nanocomposites contain isolated silver nanoparticles 2–12 nm in diameter, preferably spherical in shape, and uniformly distributed in the polymer matrix. ATR IR spectroscopy has revealed that the nanoparticles affect the state of the carboxyl groups in the polymer matrix. It has been found that the size of zero-valent silver nanoparticles depends on the ratio of monomer units in the polymer matrix. The thermo-oxidative stabilities of the synthesized copolymers and polymer nanocomposites produced on their basis have been examined.

Synthesis and characterization of silver polymer nanocomposites of 1-vinyl-1,2,4-triazole with acrylonitrile

Novel organic-inorganic nanocomposites were synthesized by chemical reduction of silver ions from silver acetate in DMSO and DMF solutions in the presence of the stabilizing copolymer of 1-vinyl-1,2,4-triazole-acrylonitrile. The solvents DMSO and DMF can act as efficient reducing agents for silver ions, which makes it possible to carry out the reaction under mild conditions and simplify procedures of nanocomposite isolation. The structure and properties of the starting copolymer and related nanocomposites were characterized by UV, IR, and 1H and 13C NMR spectroscopy, as well as transmission electron microscopy and thermogravimetry. The prepared polymer nanocomposites contain 6.8–7.2% silver in the form of nanoparticles with a size of 2–20 nm uniformly dispersed in the polymer matrix. The nanocomposites are readily soluble in DMSO and DMF and do not decompose on heating to 260 °C.

Water-soluble silver nanocomposites with 1-Vinyl-1,2,4-triazole copolymer

87 Polymer nanocomposites with silver nanoparticles are promising for medicine, optoelectronics, and nan ophotonics due to the unique properties of silver in the nanosized state and multifunctional properties of the polymer matrix [1–5]. Recently, we reported an efficient stabilization of silver nanoparticles with 1 vinyl 1,2,4 triazole homo polymer (PVT) and its copolymer with sodium meth acrylate (Na MAA) [6, 7]. In this work, we report the results on the synthesis of a new VT–Na AA copolymer and formation of water soluble silver containing nanocomposites on its basis. The copolymerization of VT with Na AA was car ried out in an aqueous solution in the presence of a radical type initiator, azobis(isobutyronitrile) (AIBN) at 60°C. The resultant copolymer as a white powder is readily soluble in water and has a characteristic viscos ity of 5.5 dL/g. The composition and structure of the copolymer were determined by elemental analysis, potentiometric titration, and IR spectroscopy. It was found that copolymer macromolecule contains VT (70 mol %) and Na AA units (27 mol %) along with acrylic acid units (3 mol %) resulting from the partial hydrolysis of Na AA molecules. The IR spectra of the copolymers contain no absorption bands of vinyl group (1654 cm–1) and show absorption bands corresponding to the stretching and bending vibrations of the triazole ring (cm–1): 3106 (C–H), 1504 (C=N), 1277 (N–N), 1005 (C–H), 664 (C–N), as well as stretching vibrations of C=O in –COOH and –COO– (1710 and 1575 cm–1, respec tively). Nanocomposites were formed in an aqueous solu tion of the obtained copolymer by the reduction of sil ver ions from silver nitrate with sodium borohydride. The prepared nanocomposites are brown powders containing 2–6% of silver readily soluble in water.

Immunomodulatory properties of silver-containing nanocomposite on the basis of polyvinyltriazole

The water-soluble nanocomposite with the uniform distribution of silver nanoparticles in polymer matrix was synthesized on the basis of poly-1-vinyl-1,2,4-triazole. Physicochemical and immunomodulatory properties of the nanocomposite were studied. The stimulating effect of the nanocomposite on the functional capability of phagocytes in vitro and potential of using it as a drug, which increases the natural resistance of organism against infectious agents, were established.

Polymer nanocomposites with iron oxide nanoparticles

Novel polymer nanocomposites with iron oxide nanoparticles in a poly(1-vinyl-1,2,4-triazole) matrix are promising for the development of new biomedical materials of long-term effect.

Silver nanocomposites based on a copolymer of 1-vinyl-1,2,4-triazole with crotonaldehyde

New polymer silver nanocomposites were synthesized using a copolymer of 1-vinyl-1,2,4-triazole with crotonaldehyde as the silver ion reducing agent and stabilizer of metal nanoparticles. The formation of the metallic phase in the nanoscale state was confirmed by UV spectroscopy and X-ray phase analysis. According to the transmission electron microscopy, nanoparticles have sizes of 2—14 nm and are uniformly distributed in the volume of the polymeric matrix.

Complexes of 1-(methylaminomethyl)silatrane with transition metal chlorides

Silatranes XSi(OCH2CH2)3N constitute a unique class of heterocyclic five-coordinate silicon compounds possessing a dative N→Si bond, and they attract strong and continuously increasing interest [1]. Of particular importance is the basicity of silatranes, which determines mechanisms of many their chemical reactions [2]. We previously synthesized complexes of 1-(3,5-dimethyl-1H-pyrazol-1-ylmethyl)silatrane (L) with zinc chloride and cobalt chloride L · MCl2 (M = Zn, Co), in which the transition metal closes a sixmembered chelate ring via coordination of the pyrazole nitrogen atom and endocyclic oxygen atom in the silatrane fragment [3].

Hydrophilic functional copolymers of 1-vinyl-1,2,4-triazole with vinylsulfonic acid sodium salt

The free-radical copolymerization of 1-vinyl-1,2,4-triazole with vinylsulfonic acid sodium salt was conducted. New thermally stable functional water-soluble copolymers of various composition were synthesized. The structure and properties of the obtained copolymers were confirmed by IR, 1H NMR spectroscopy, and thermogravimetric methods. It was found that 1-vinyl-1,2,4-triazole has higher reactivity than sodium vinylsulfonate. TGA and DSC show that the produced copolymers are stable when heated to 260 °C.

Fe-containing nanocomposites based on a biocompatible copolymer 1-vinyl-1,2,4-triazole with N-vinylpyrrolidone

New polymer nanocomposites containing iron oxide nanoparticles stabilized with a biocompatible copolymer of 1-vinyl-1,2,4-triazole with N-vinylpyrrolidone were produced. The synthesis was conducted using the method of chemical reduction of iron ions with hydrazine hydrate in an aqueous medium in the presence of a polymer matrix. The ESR spectroscopy data showed that the core—shell type nanoparticles were obtained. The core generally consistsed of zero-valence iron coated with an oxide shell. According to the data of transmission electron microscopy, the obtained polymer nanocomposites consisted of nanoparticles of mainly spherical shape with a diameter from 1 to 14 nm. Aggregates formed from individual stabilized nanoparticles of up to 75 nm in size (in most cases) were also observed. These aggregated particles were found to self-organize and form branched chains. Nanocomposites were characterized by a different particle-size distribution, which was determined by the initial ratio of the copolymer and the precursor of iron nanoparticles.

Functional Copolymers Containing Triazole and Carboxylic Groups

ISSN 00125008, Doklady Chemistry, 2014, Vol. 454, Part 2, pp. 42–45.