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.     

Radiation-Induced Cryopolymerization of Epichlorohydrin

The polymerization of epichlorohydrin occurs in the temperature region of glass transition as a result of heating of the samples preirradiated at 77 K. The specific heat of polymerization of epichlorohydrin Hwas determined to be 95.4 ± 6.0 kJ/mol. The postirradiation polymerization proceeds through the cationic mechanism. The chain propagation rate constant was estimated at k _p= 10^–18exp(–14200/RT) cm³/s for the temperature range 95–140 K. The dynamics of postirradiation polymerization of crystalline epichlorohydrin is substantially different from the polymerization dynamics of the glassy monomer. The polymer yields were found to be 3 and 12% for the crystalline and the glassy monomer, respectively. Heating of an irradiated glassy solution of hydrogen cyanide in epichlorohydrin results in the formation of the corresponding copolymer.     

Preparation and properties of composites based on caramelized aluminoborosilicate fabric and tetrafluoroethylene telomers

New composites based on activated caramelized aluminoborosilicate glass fabric and radiationsynthesized tetrafluoroethylene telomer solutions were prepared, and their properties were studied. The properties of materials prepared from standard commercial and caramelized glass fabrics were compared.     

Hydrophobization of Melamine Sponges Using Radiation-Synthesized Tetrafluoroethylene Telomers

High Energy Chemistry - The process of hydrophobization of melamine sponges has been investigated. Solutions of radiation-synthesized tetrafluoroethylene telomers, which had different chain lengths...     

Fluoropolymer Composite Materials and Protective Coatings for the Extreme Conditions of the Arctic Zone

Russian Journal of General Chemistry - Specific aspects of the use of radiation-synthesized tetrafluoroethylene telomers for creation of new fluoropolymer composite materials and protective...     

Cellulose from Annual Plants and Its Use for the Production of the Films Hydrophobized with Tetrafluoroethylene Telomers

Cellulose HogC was produced by the modified traditional method with 35% yield from the stem of Sosnovsky hogweed and was characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffractometry, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). For HogC, the degree of crystallinity (approximately 70%) and the glass transition temperature (105–108 °C) were determined. It was found that the whiteness characteristic in the case of HogC was 92% and this significate was obtained without a bleaching procedure using chlorine-containing reagents. In this paper, the possibility of hydrophobization of HogC films by treatment with radiation-synthesized telomers of tetrafluoroethylene is shown. It was found that the contact angle of the telomer-treated cellulose film surface depended on the properties of the telomers (the chemical nature of the solvent, and the initial concentration of tetrafluoroethylene) and could reach 140 degrees.     

Processes occurring during the interaction of molecular bromine with acrylamide at low temperatures and upon heating the mixture

It has been shown that the addition of molecular bromine to the monomer acrylamide (AA) results in the spontaneous formation of radicals. During heating the AA + Br₂ mixture, the radicals initiate polymerization and bromination reactions. Beginning well below the melting point of bromine, both the reactions proceed at a noticeable rate at its melting temperature.     

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.