Synthesis of <Emphasis Type="Italic">N</Emphasis>-vinyl-2-pyrrolidone–3-butenoic acid copolymers as drug carriers

New water-soluble copolymers of N-vinylpyrrolidone with 3-butenoic acid were prepared by radical copolymerization initiated with azobis(isobutyronitrile) or γ-radiation. The relative activities of the monomers in copolymerization were determined. The distribution of the units in the copolymer macrochains was calculated. The composition, molecular and hydrodynamic characteristics, and acute toxicity of the copolymers were determined. The copolymers were used as carriers for rifampicin antibiotic.     

Postradiation copolymerization of N-vinylpyrrolidone with triethylene glycol dimethacrylate

The kinetics of low-temperature postradiation copolymerization of N-vinylpyrrolidone (N-VP) with triethylene glycol dimethacrylate (TGM-3) were studied using reactant mixtures with different compositions and different pre-irradiation doses, and the characteristics of the obtained copolymers were determined. The copolymerization process is most effective in glassy systems (at an N-VP concentration in solution below 80 mol %). It was shown that a poly-N-vinylpyrrolidone homopolymer is formed along with a crosslinked N-VP-TGM-3 copolymer.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-vinylpyrrolidone copolymers with 2-aminoethyl methacrylate as drug carriers

Radical copolymerization of N-vinylpyrrolidone and 2-aminoethyl methacrylate hydrochloride has been studied. Molecular and hydrodynamic characteristics of the resulting copolymers have been determined, and their structure has been confirmed. Conditions favoring conversion of these copolymers into copolymers of N-vinylpyrrolidone with 2-aminoethyl methacrylate of different composition have been elucidated. The suitability of the prepared copolymers as polymeric carriers of monofluoroquinolone ofloxacin has been demonstrated.     

Low-temperature radiation-initiated copolymerization of N-vinylpyrrolidone with acrylic acid in glass-forming ethanol or dimethylformamide solutions

The radiation-initiated copolymerization of N-vinylpyrrolidone with acrylic acid at low temperatures in glass-forming ethanol or dimethylformamide solutions was studied. The mechanism of the copolymer formation was elucidated, and conditions were determined for preparing alternating and random block copolymers.     

Water-soluble poly(n-vinylamides)as a basis for the synthesis of polymeric carriers of biologically active compounds

The method for preparation of copolymers of N-vinylpyrrolidone (VP) and N-vinylamine (VA) with high yield were developed; the method involves radical copolymerization of VP with N-vinylformamide(VFA) followed by the removal of formyl protecting group in the presence of inorganic acids. The optimal conditions for synthesis of copolymers with predefined compositions and molecular masses were determined. The influence of temperature, concentrations of reactants, and the nature of an acid on the rate of formyl group removal was estimated. Spectral and chromatographic methods of analytical control of the contents of residual monomers and formic acid (which forms during acidic hydrolysis of the copolymer) were developed.     

Radiation-Initiated Copolymerization of <Emphasis Type="Italic">N</Emphasis>-Vinylpyrrolidone with Triethylene Glycol Dimethacrylate

The kinetics of radiation-initiated copolymerization of N-vinylpyrrolidone with triethylene glycol dimethacrylate was studied. The variation of the composition of the 3D cross-linked copolymer and of the amount of N-vinylpyrrolidone homopolymer in the course of the process at various initial monomer ratios was monitored.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 5, 2005, pp. 814–817.Original Russian Text Copyright © 2005 by Kiryukhin, Kichigina, Zubakova, Moskvina.     

Quinone copolymerization. I. Reactions of p-chloranil,p-benzoquinone,and 2,5-dimethyl-p-benzoquinone with vinyl monomers under free-radical initiation

The free-radical copolymerization reactions of p-chloranil, p-benzoquinone, and 2,5-di-methyl-p-benzoquinone with vinyl monomers were studied. Reactions of p-chloranil with styrene yielded copolymers of approximately 1:1 composition under a variety of reaction conditions. A copolymer containing a block of 1:1 of styrene:p-chloranil and a block of polystyrene was prepared. Several styrene-like monomers copolymerized with p-chloranil to yield copolymrs possessing considerable amounts of incorporated quinone. p-Benzoquinone copolymerized with 1,3-butadiene and 2-vinyl-pyridine to yield copolymers of significant molecular weights. Reactions of 2,5-dimethyl-p-benzoquinone with vinyl monomers did not yield any isolable polymeric products.     

Copolymerization of N-vinylpyrrolidone with N-allylated acylhydrazines

The free-radical copolymerization of N-vinylpyrrolidone with N,N-diallyl-N′-acetylhydrazine and N,N-diallyl-N′-butanoylhydrazine has been investigated in bulk and solution. The copolymerization yields random copolymers enriched with N-vinylpyrrolidone units. The kinetic study of the reaction has revealed that the rate of copolymerization decreases with a rise in the fraction of an allyl monomer in the initial monomer mixture. Both double bonds of diallylacylhydrazines are involved in the copolymerization to give rise to five-membered pyrrolidine rings.     

Laser-Initiated copolymerization of N-vinylpyrrolidone with maleic anhydride and maleimide

This article describes the laser-initiated copolymerization of N-vinylpyrrolidone with maleic anhydride and maleimide via charge transfer complexes. The dependence of copolymer yield on the molar ratios of the monomers in the feed and on the irradiation time is described. Based on the ultraviolet and infrared spectroscopy, and chemical analysis results, a tentative mechanism of polymerization is suggested. The rates of polymerization of several monomer systems are compared. The N-vinylpyrrolidone and maleimide system shows the highest rate of polymerization.     

Water-soluble polymer derivatives of cholesterol

New cholesterol-containing water-soluble polymers based on N-methacryloyl aminoglucose and N-vinylpyrrolidone are synthesized by free-radical copolymerization and polymer-analogous transformations. Binary and ternary copolymers of various composition containing N-allylamine and N,N,N-trimethylaminoethyl methacrylate methyl sulfate units and cholesterol residues are prepared. Luminescently labeled copolymers of the same composition are obtained. Effects of the nature of polymers and the amount of cholesterol in them on the intramolecular mobility of macromolecules in solution are studied with polarized luminescence. When 2–4 mol % of cholesterol residues are incorporated into the copolymer, the intramolecular mobility of macromolecules decreases, thus indicating formation of intramolecular compact structures via interaction of nonpolar cholesterol groups. In copolymers containing charged groups, these structures are looser than those in neutral copolymers. It is shown that macromolecules of cholesterol-containing polymers of various types can interact with each other. 1 This work was supported by the Russian Foundation for Basic Research (project no. 08-03-00324) and the Council for Grants of the President of the Russian Federation for Support of Leading Institutes of Higher Education (NSh-4391.2008.3).     

Oxidation of Hydroquinone By (N-Vinylpyrrolidone)-(4-Vinylpyridine) Block and Graft Copolymers

ABSTRACT

A-B Type block copolymer of N-vinylpyrrolidone (NVP) and 4-vinylpyridine (VPy) [poly(NVP-b-VPy) and graft copolymers of VPy onto copolymers of NVP with 4-vinylbenzyl N,N-diethyldithiocarbamate (VBDC) [poly(NVP-g-VPy) were synthesized by the iniferter method. the compatibility between NVP and VPy units in the copolymers was evaluated from the glass transition temperature of these copolymers. Hydroquinone was then oxidized by the synthesized NVP-VPy copolymers-Cu(II) complex catalysts. the influence of the distribution of each monomer unit in copolymers on the catalytic activity was studied by comparing the activity of these copolymers. the catalytic activity of these copolymers increased in the order: NVP-VPy blend polymer, poly(NVP-b-VPy), poly(NVP-g-VPy), random copolymer [poly(NVP-ran-VPy)]. This order parallels the compatibility between NVP units and VPy units in these copolymers.     

Copolymerization of <Emphasis Type="Italic">N</Emphasis>-vinylpyrrolidone with new allyl monomers

Radical copolymerization of N-vinylpyrrolidone with diallylacylhydrazines, 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride, N-allyl-2-azanorborn-5-ene, and N-allylmaleimide in the bulk and in organic solvents was studied. The kinetic features of the reactions were examined, the structures of the copolymers obtained were determined, and their physicochemical and biological properties were studied.     

Radical copolymerization of N-vinylpyrrolidone with methyl methacrylate and styrene in the presence of C-phenyl-N-tert-butylnitrone

The effect of C-phenyl-N-tert-butylnitrone on the features of radical copolymerization of N-vinylpyrrolidone with methyl methacrylate and styrene was examined. Nitrone exerts virtually no effect on the relative activities of the comonomers. At the same time, C-phenyl-N-tert-butylnitrone as a potential source of nitroxyl radical makes it possible to prepare copolymers of N-vinylpyrrolidone with methyl methacrylate and styrene to high conversions without gel effect, to control the molecular-weight characteristics of the copolymers, and to prepare block copolymers. Original Russian Text ? D.F. Grishin, E.V. Kolyakina, V.V. Polyanskova, I.D. Grishin, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 1, pp. 123–131.     

Synthesis of N-Vinylpyrrolidone-Vinyltrimethoxysilane Copolymers

N-Vinylpyrrolidone-vinyltrimethoxysilane copolymers were prepared by radical copolymerization. The composition of the copolymer was studied in relation to the reaction temperature and composition of the initial mixture. The kinetic parameters of the monomer activity were calculated.     

Formation of N-vinylpyrrolidone homopolymer and its grafting during radiation-induced copolymerization with triethylene glycol dimethacrylate

The kinetics of radiation-induced copolymerization of N-vinylpyrrolidone with triethylene glycol dimethacrylate was studied. It was shown that the formation of a water-soluble N-vinylpyrrolidone homopolymer and its subsequent grafting onto the copolymer takes place in the system during the process. Copolymers containing up to 90 mol % N-vinylpyrrolidone in the macromolecular chain to provide their high sorption power were obtained.     

Molecular and associative properties of <Emphasis Type="Italic">N</Emphasis>-vinylpyrrolidone copolymers with <Emphasis Type="Italic">N</Emphasis>-crotonoylaminocaproic acid in dilute solutions

The random copolymers of N-vinylpyrrolidone and N-crotonoylaminocaproic acid attractive for the modification of drugs are studied by static and dynamic light scattering, viscometry, and sedimentation-diffusion analysis. The content of functional groups in the copolymers is 14.1–27.0 mol %. Analysis is performed in 0.1 N aqueous solutions of sodium acetate and dimethylformamide. The molecular characteristics of the copolymers with various composition are determined. It is shown that supramolecular structures are present in copolymer solutions and their amount depends on copolymer composition; the effect of solvent on the formation of these structures is ascertained.     

Copolymerization of styrene with methyl methacrylate in the presence of the system tributylborane–<Emphasis Type="Italic">p</Emphasis>-quinone

The copolymerization of styrene with methyl methacrylate at 80°C in the presence of catalytic system tributylborane–p-quinone (1,4-naphthoquinone, duroquinone) has been studied. The copolymerization proceeds via the mechanism of the reversible inhibition. The number-average molecular weights of the copolymers linearly increase with progress in monomer conversion. The contribution of the “living” mechanism in the total process depends on the structure of the quinone. Reactivity ratios of the monomers differ from the values known for conventional radical polymerization. The experimental data of triad concentration and average composition correlate with theoretical value.     

Copolymerization of N-vinylpyrrolidone with acrylic monomers in vitrifying solutions

The low-temperature copolymerization of N-vinylpyrrolidone with acrylic monomers (acrylic acid, acrylamide, and methyl acrylate) in vitrifying solutions in ethanol and DMF has been studied. It has been shown that the copolymerization proceeds after transition of preliminarily γ-irradiated at 77 K samples from the solid glassy state to a supercooled liquid. Experimental conditions that ensure formation of alternating and random block copolymers have been established. The composition of copolymers is determined by the relative mobility and initial ratio of comonomers in solution.     

Mechanism of alternating copolymerization of 4-hydroxy-4′-vinylbiphenyl with α-chloromaleic anhydride

The copolymerization of 4-hydroxy-4′-vinylbiphenyl (HVB) with α-chloromaleic anhydride (CMAn) was investigated in THF, 1,4-dioxane, and acetonitrile. The formation of the 1:1 charge transfer complex between HVB and CMAn was confirmed spectroscopically, and the corresponding equilibrium constant (K_eq) was determined as follows: K_eq = 0.19, 0.11, and 0.058 mol/L in THF, 1,4-dioxane, and CH₃CN, respectively. The copolymer composition is affected by the solvent, i.e., the content of HVB in the copolymer obtained in THF or 1,4-dioxane is lower than 50 mol % whereas the copolymer obtained in CH₃CN has excess of HVB units. The maximum rate of copolymerization was observed at a 1:1 initial comonomer mole ratio, irrespective of the solvent polarity. Plots of R_p/[HVB] vs. [HVB] gave a straight line with a slope and an intercept for the copolymerization in THF whereas a straight line in CH₃CN has no slope. On the basis of these results and ¹³C-NMR spectra of the copolymers, the mechanism of the predominant formation of alternating copolymers is discussed.     

Synthesis and properties of fullerene-containing N-vinylpyrrolidone copolymers

Branched copolymers containing covalently bonded fullerene C₆₀ were synthesized by cross-linking radical copolymerization of N-vinylpyrrolidone with triethylene glycol dimethacrylate in toluene saturated with fullerene. Their composition was studied by elemental analysis and IR and electronic absorption spectroscopy. The concentration of double bonds, characteristic viscosity, and glass-transition temperature of the fullerene-containing copolymers were determined by ozonoliysis, viscosimetry, and differential scanning calorimetry. The parameters and thermal stability of the fullerene-containing copolymers were compared with those of their non-functionalized analogs.