Mean square of the dipole moment of a macromolecule as a function of the ordering of its monomeric units

The most important information for the practical use of flexible-chain polymers is the change in structure in the presence of external influences. A conformational model for calculating the mean square of the dipole moment of a macromolecule is constructed in this work, provided that there is no correlation between the conformations of monomer units in a heterogeneous temperature field.

Research of the mechanisms of penetration of toxic chemicals through a multilayer composite sorption-active material

The mechanism of penetration of liquid and vapors of a simulator of toxic chemicals through samples of multilayer sorptionactive materials obtained by the method of double-sided duplication, differing in different structure and composition, has been determined.The optimal structure of a multilayer composite sorption-active material has been selected for the manufacture of personal protective equipment for the skin of a filtering type, which provides high hygienic and protective properties as close as possible to materials of an insulating type, as well as a technology for its production.

Physicochemical properties of oligo(ethylene glycol) (meth)acrylates

This review summarizes the literature data on the physicochemical properties of oligo(ethylene glycol) (meth)acrylates. The influence of the structure of these macromonomers on their solubility, tendency to association in solutions, interfacial activity, reactivity in reactions of acid- and base-catalyzed hydrolysis, radical homo- and copolymerization is considered.

Regularities of the radical copolymerization of dodecyl (meth) acrylate and a new cationic monomer N-(dibutylaminomethyl) methacrylamide

The regularities of radical copolymerization of dodecyl methacrylate (DMA) or dodecyl acrylate (DA) with a new cationic monomer - N-(dibutylaminomethyl) methacrylamide (DBAMMA) in toluene solutions were determined. The copolymers formed at low conversions in the DMA-DBAMMA system are enriched in ether units, and in the DA-DBAMMA system - in aminoamide units. The relative activities of comonomers determined by the Feineman-Ross and Kehlen-Tudosh methods in the first case were 1.56-1.60 (DMA) and 0.87-0.89 (DBAMMA), in the second case - 0.53-0.64 (DA) and 0.80-0.90 (DBAMMA).

Development of composite materials based on chrome-containing waste and polyurethane binder

The results of a study of the effect of the type and consumption of binder and plasticizers on the physicochemical characteristics of composite materials obtained using chromium-containing fibrous wastes from leather production are presented. The absence of chromium compounds in water extracts of composites has been established, which confirms the environmental safety of new composite materials.

Impact of the plasma flow of a low-pressure high-frequency capacitive discharge on the adhesive and physical and mechanical characteristics of aramid and carbon fibers

The changes in the adhesive and physico-mechanical characteristics of aramid and carbon fibers treated with plasma of a highfrequency capacitive gas discharge of reduced pressure are considered. An increase of ~ 30% in the wettability of the surface of aramid and carbon fibers is shown. It was found that the strength of plastics made on the basis of aramid and carbon fibers treated with a plasma flow increases by ~ 26%.

Technological features of reactive dynamic extrusion of nanocomposites based on polyolefins, aluminum and technical carbon

The effect of the concentration of aluminum powder and technical carbon nanoparticles on the main physical and mechanical properties of nanocomposites based on high density polyethylene, low density polyethylene and an ethylene-hexene copolymer is considered. The optimal technological parameters of the reaction extrusion of nanocomposites vulcanized with sulfur and dicumyl peroxide have been determined. The influence of the type of polyolefin, fillers and crosslinking agents on the formation of isotropic nanocomposites during the production of sheet products has been investigated.

Prospects for obtaining phenol-formaldehyde oligomers

The article provides an overview of recent studies in the development of new methods for the synthesis and use of phenolformaldehyde oligomers. Prospects for carrying out scientific work in this direction, associated with the availability of raw materials, technological and applied aspects, have been substantiated. The main areas of application of phenolic resins have been identified. Special attention is paid to coatings, adhesives, binders, as well as carbon foams based on them. New methods for the modification of phenol-formaldehyde oligomers are described, as well as new compositions of modifying agents for the purposeful change in the complex of their properties.

New combined method of the thermoplastics turning

The article presents the results of experimental studies of thermoplastic turning with the use of advancing vacuum treatment of the work piece surface. It has been experimentally proven that turning thermoplastics with advancing vacuum treatment of the surface of the work pieces leads to a better machined surface of the part in comparison with the traditional turning method.

Calculation of polymer properties by chemical structure and composition. Part 2.

The article presents methods for calculating and assessment the physical and mechanical characteristics of such a class of polymers as polyolefins by their chemical structure and composition in the entire possible range of application temperatures and frequencies based on model concepts.