Polymer Science, Series D最新文献

Ultrasonic liquid processing allows for the intensification of technological processes based on the use of dispersed systems.Despite certain advances in individual systems, there are currently no studies aimed at establishing the relationship between the liquid medium and the dispersed phase properties and the ultrasonic processing parameters that determine cavitation-erosion activity and the intensity of acoustic flows. This study was conducted on model dispersed systems with varying viscosities and is divided into two parts. The first examines the effect of liquid viscosity on the propagation of cavitation region and its erosive activity. The second examines the change in cavitation-erosion activity upon the addition of a dispersed phase to the liquid.

A production technology of a modified colorless phenol formaldehyde resin of the SF-BP brand which will find application in the production of paper–resin films intended for finishing of wood board materials as well as in the fabrication of laminated paper plastics is presented. The properties of the synthesized resin are studied. Process parameters of the production process of paper–resin films with the use of the modified resin are developed as well as the assessment of the quality of these films is performed. The modes of hot lamination of a wood board material by way of example of plywood as well as modes of pressing of laminated paper plastic are developed. The results of determination of the physical and mechanical properties of the obtained composites are presented.

A new copolymer based on benzocyclobutene-4-yl vinyldimethylsilane has been developed and synthesized for application in the manufacture of printed circuit boards. The influence of the copolymer composition on the viscosity of its solutions in mesitylene has been established, and concentration dependences of viscosity have been obtained. The possibility of using solutions of the benzocyclobutene-4-yl vinyldimethylsilane copolymer as a binder for producing prepregs for the manufacture of fiberglass laminates has been demonstrated. The dielectric properties of the obtained fiberglass laminate allow recommending it for use in the production technologies of microwave printed circuit boards.

This article presents studies of a nondrying compound based on epoxy-terminated polythioether containing corrosion inhibitors. Relationship between the Brookfield dynamic viscosity and flowability of nondrying compound and the type and amount of filler was studied. Tests have been carried out to determine the compound’s protective ability when applied between dissimilar metals and exposed to a salt spray chamber, as well as its resistance to mold fungi.

Thermodynamic composite material composition for the design and manufacture of a medical prosthesis was selected, taking into account biocompatibility and deformation–strength properties. Chalk was used as a filler, and an organosilicon polymer was used as a polymer matrix. A prosthesis model was developed, and the optimal ratio of its components was determined through calculations.

The implementation of the process of extrusion 3D printing for solutions of chitosan is complicated in view of the low shape stability of its printed structures, while introduction of a crosslinking agent does not provide immediate formation of an elastic hydrogel after extrusion. The paper proposes a method for obtaining chitosan-containing hydrogel structures by combining agar with chitosan in the composition of printing “ink,” which makes it possible to form a shape-stable material with the biological activity inherent to chitosan. The physicochemical properties of hydrogels based on agar and chitosan as well as their compositions modified with genipin are studied. It is found that introducing chitosan into hot solutions of agar results in a decrease in the temperature and a change in the kinetics of gel formation. The use of genipin as a crosslinking agent makes it possible to obtain resistant to the action of the environment hydrogels suitable for direct extrusion 3D printing (direct ink writing (DIW)). Thermally reversible hydrogel ink with the optimum agar/chitosan ratio are developed which demonstrate good shape stability and high resolution during printing. The obtained results of the work open up prospects for using this system in the field of biomedicine, food industry, and cosmetology.

This article presents a comparative analysis of two methods for determining the adhesion strength between an epoxy matrix and carbon fiber: pull-out and an improved knot-pulling method. The study identified the main advantages and disadvantages of each method. The consistency of test results obtained using the pull-out and knot-pulling methods was established. Results of optical microscopy studies of the adhesive contact zone are presented.

This article proposes a method for preparing a surface for bonding 3D-printed acrylonitrile–styrene–acrylate (ASA) with epoxy resin. Effect of the fill rate (0, 30, 60, 90%) of the bonded part on the shear strength of adhesive joint is studied. It was found that samples with 60% fill rate exhibit maximum strength, with failure occurring at the base rather than the adhesive joint. Optimal surface preparation improves adhesion and bond strength. Method developed can be used in the production of large-scale parts using 3D-printed ASA.

This paper establishes the mechanism of interaction at the phase interface during electrochemical copper plating of a carbon fiber-based composite with an adhesive mixture of methyl methacrylate and silicone sealant. The influence of galvanic copper plating parameters on the metallized composite’ structure and properties is demonstrated. Thus, at an electrolysis current density of 50 mA/cm², a high-quality coating of required thickness with the best microhardness, adhesion, and electrical resistivity can be obtained.

Influence of various fillers (kaolin, NDP-D-400 diatomaceous earth, NDP-230 diatomaceous earth, natural chalk, and microquartz) on the vulcanization characteristics of a rubber compound, as well as the physical, mechanical, and performance properties of rubber based on a combination of ethylene propylene diene S 505A and nitrile butadiene SKN 2645 rubbers, was studied. It was shown that rubber containing kaolin at a rate of 20.0 parts per hundred parts of rubber (phr) exhibits stable physical and mechanical properties and minimal changes in elastic strength properties. It is resistant to hydrocarbon environments and can be recommended for the manufacture of sealing components used in the automotive industry.