Physicochemical Properties of Complexes of Zinc Iodide with Pyridine N-Oxides

Polycrystalline 1 : 2 complexes of ZnI₂ with N-oxides of pyridine, picoline, and 2,6-lutidine were studied by IR spectroscopy, dielectrometry, and conductometry. An equilibrium between three solid phases was observed. These phases are characterized by different enthalpies of formation of intermolecular bonds and different mechanism of electronic effect transmission via these bonds. Gas-like thermal molecular motion in one of the phases of the 2,6-lutidine N-oxide complex was observed. Reversible chemical reactions on the surface of the crystalline 3-picoline N-oxide complex are initiated on exposure to an alternating electric field. Two complexes, similarly to the ZnCl₂ complexes, are ionized in the cumulative mode on fast heating from 18-19 to 26-45°C. Partial activation energies of electrical conductivity of different ions were determined for a number of complexes and inorganic salts.     

Permeation and sorption in polynorbornenes with organosilicon substituents

Gas sorption properties, permeability coefficients, and diffusion coefficients of a series of norbornene polymers are presented. Introduction of the Si(CH₃)₃ group into the polynorbornene (PNB) backbone chain results in significant increases in glass transition temperature, permeability, and diffusion coefficient for a number of gases (H₂, O₂, N₂, CO₂, CH₄, C₂H₆). The transport properties and sorption isotherms for poly(5-trimethylsilyl norbornene) (PTMSNB) are very similar to those for poly(vinyltrimethyl silane) (PVTMS), which contains the same side-chain group but differs from PTMSNB by the structure of its main chain. For another silicon-containing polymer poly[5-(1,1,3,3-tetramethyl-1,3-disilabutyl) norbornene] (PDSNB) having a bulkier side-chain group, the glass-transition temperature is decreased in comparison with that of PNB, presumably owing to self-plasticization. Both silicon-containing norbornene polymers (PTMSNB and PDSNB) have permeability coefficients for “rapid” gases like H₂ or CO₂ of about 10² Barrer. The high values of the Langmuir sorption capacity C′_H for PTMSNB and PVTMS, as well as the high diffusivity and mobility of spin probes in these polymers, were attributed to a large free volume related to the bulky Si(CH₃)₃ groups attached directly to the main chain. © 1993 John Wiley & Sons, Inc.     

2-Amino-3-(benzimidazol-2-yl)benzo[b]furans

The corresponding 2-amino-3-(benzimidazol-2-yl)benzo[b]furans were obtained by reaction of 2,3,5-trimethyl-1,4-benzoquinone with 2-cyanomethylbenzimidazoles. It is shown that new benzo[b]furo[2′,3′∶4,5]pyrimido[1,6-a]benzimidazole polynuclear heterocyclic systems (bases and quaternary salts) are formed in the reaction of these products with acylating agents. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 164–166, February, 1980.     

A Procedure for Measuring the Viscosity of Formulations Based on Oligourethane Acrylates for UV-Curable Protective Coatings of Fiber Light Guides

A capillary viscometric procedure was developed for measuring the viscosity of formulations based on oligourethane acrylates for UV-curable protective coatings of fiber light guides. The temperature dependences of the viscosities of these formulations were studied. The moduli of elasticity of fibers prepared from these formulations after UV curing were measured. These formulations can be stably applied, using a die, to the surface of fiber light guides in the course of their drawing at a drawing rate of up to 100-120 m min^-1.     

Metathesis of spirocyclo[2.2.1]hept-2-ene-7,1'-cyclopropane

Metathesis of spirocyclo[2.2.1]hept-2-ene-7,1'-cyclopropane and its co-metathesis with norbornene and 5-decene on homogeneous and heterogeneous catalytic systems were carried out for the first time. The reactions were shown to proceed with retention of the spirosystem.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 138–139, January, 1993.