Surface modification of cellulose-containing materials with solutions of tetrafluoroethylene telomers

Russian Journal of Applied Chemistry - Modification of cellulose-containing materials (wood veneer, paper) with solutions of radiationsynthesized tetrafluoroethylene telomers was studied. Treatment...     

Radiation-Chemical Synthesis of Perfluorinated Tetrafluoroethylene Telomers

High Energy Chemistry - The kinetics of radiation-initiated telomerization of tetrafluoroethylene in perfluoromethylcyclohexane and perfluoro-1,3-dimethylcyclohexane has been studied, and new...     

Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry

Appearance energies of [M-H](-) ions from carbonyl compounds R-CO-R' (R,R' = H, CH(3), NH(2), OH) have been measured by means of negative ion mass spectrometry in resonant electron capture mode. Values of electron affinity of the corresponding radicals, CH(2)&dbond;C(X)O, NH&dbond;C(X)O and O&dbond;C(X)O, have been determined. Copyright 1999 John Wiley & Sons, Ltd.     

Low-temperature radiation chemistry

An overview of studies on the radiation-initiated chemical reactions of polymerization, copolymerization, graft polymerization, telomerization, oxidation, cryoozonolysis, hydrobromination of olefins, and chlorination of paraffins occurring at low and ultralow temperatures has been presented. Particular attention has been paid to self-oscillating reactions.     

Tetrafluoroethylene telomers: Radiation-initiated chemical synthesis, properties, and application prospects

Systematic studies devoted to the radiation-chemical synthesis of solutions of tetrafluoroethylene telomers in various solvents are summarized. The properties and application prospects of tetrafluoroethylene telomers are considered. Radiation initiation allows new functional products with a broad spectrum of properties to be obtained and new technological approaches with the use of fluorinated polymers to be developed.     

Hydrophobization of polyester textile materials with telomeric tetrafluoroethylene solutions

Hydrophobic coatings formed on a polyester fabric by treatment with telomeric solutions prepared by a radiation-chemical procedure in acetone and butyl chloride were studied by IR spectroscopy (MATIR), energy-dispersive analysis, and atomic force microscopy. The hydrophobic properties of the textile material were evaluated by procedures traditional for textile chemistry. Conditions determining the formation of a thin, highly hydrophobic, uniform, and flawless coating resistant to the effect of operation factors were suggested.     

Low-temperature radiation telomerization of tetrafluoroethylene in hexafluoroisopropanol

The kinetics of low-temperature (180–270 K) postradiation telomerization of tetrafluoroethylene in hexafluoroisopropanol has been investigated. The efficiency of the process is determined by the initial concentration of the monomer in the solvent and the dose of preliminary irradiation. It has been shown that the telomerization reaction proceeds via the radical mechanism during the devitrification of the system. Active centers that initiate the process and their yield at 77 K have been studied by the ESR technique. Some properties of the product telomers have been studied.     

The specifics of radiation telomerization of tetrafluoroethylene in chlorinated solvents and telomer properties

Radiation telomerization of tetrafluoroethylene in butyl chloride, chloroform, and carbon tetrachloride has been investigated. The chain length of telomers and their solubility and thermal stability depend on the initial monomer concentration and telogen properties. In the case of telomerization in chloroform and carbon tetrachloride, the yield, the chain length, and the thermal stability of the telomers are significantly higher than those in butyl chloride, in which the process is less efficient but soluble telomers having a short chain length and exhibiting quite high thermal resistance are produced. The molecular structure of the telomers has been studied by IR spectroscopy.     

Radiation telomerization of tetrafluoroethylene in chlorinated telogens at a constant reactor pressure

The kinetics of the radiation-initiated telomerization of tetrafluoroethylene (TFE) in the solutions of telogens (butyl chloride, chloroform, methylene chloride, and carbon tetrachloride) at a constant monomer pressure in the reactor was studied. In the course of the Γ-irradiation of the reaction mixture, TFE telomers containing repeatedly soluble and insoluble fractions were formed. In chloroform, methylene chloride, and carbon tetrachloride, the rapidly occurring process of the synthesis of insoluble telomer made the main contribution to the total yield of products. For the solutions of TFE in butyl chloride, the rates of formation of soluble and insoluble telomers were almost the same. The average chain length and the thermal stability of the resulting telomers were evaluated.