Nanotechnologies in Construction: A Scientific Internet-Journal

6–13

Authors: Boev E.V., Islamutdinova A.A., Aminova E.K.

ABSTRACT: Introduction. At present, the use of polymer coatings in the protection of metallic materials and structures is becoming popular in the construction industry. It is especially important to obtain nanostructured polymer insulating materials with high anticorrosive properties in order to ensure the service life of the equipment of the fuel and energy complex. Technological equipment during the extraction, transportation, processing of petrochemical raw materials is subject to regular exposure to aggressive environments. Damage to production equipment causes annual environmental damage and human health and material burden on the enterprise. The introduction of heteroatoms into the structure of the polymer molecule helps to improve the physico-chemical characteristics of polymer coatings, in particular, to increase the protective properties, since natural and synthetic polymer compounds represent a large cluster of supramolecular structures located in a certain sequence. Methods and materials. A technology has been developed for obtaining new polymeric nanostructured alkenylsuccinimides with anticorrosive properties, which can be used as part of lubricating coatings in various industries, including construction. Alkenylsuccinimides were tested according to TS 38101147-77 for succinimide additives and showed compliance with their standards TS 38101247-77. Results and discussions. In the course of the research a resource-saving non-waste technology of obtaining a nanostructured polymer additive with polyamines as a nanostructuring base to provide an anticorrosive effect has been developed. Conclusion. The obtained compounds based on triethylenetetramine, tetraethylenepentamine, alkenylsuccinic anhydride can be used as effective polymeric anticorrosion additives in the processing of metal materials and structures in the construction industry.

27–36

Authors: Massalimov I.A., Chuikin A.E., Massalimov B.I., Mustafin A.G.

ABSTRACT. Introduction. Impregnation with a new solution based on potassium polysulfide showed excellent results in the hydrophobization of cement stone and cement-sand mortar due to the formation of a nanoscale water-repellent coating on the surface of the pores from sulfur nanoparticles formed as a result of the destruction of the molecule during the drying process. An innovative solution based on potassium polysulfide refers to polysulfur compounds, from which, as a result of the destruction of polysulfide molecules, a nanoscale layer of sulfur particles is formed on the surface. Materials and research methods. Potassium polysulfide solutions of different densities were used for impregnation; the properties of the solutions were tested on cubic samples with a 40 mm edge, made on the basis of cement and cement-sand mortar. Particle characteristics were evaluated using a laser particle size analyzer, an electron microscope and a diffractometer. Results. The analysis showed that the average size of the particles forming the protective coating is 20 nm, they have a spherically symmetric shape and crystallize into an orthorhombic crystal lattice structure. The treatment of concrete with a solution of potassium polysulfide ensures the formation of a coating based on nanosized sulfur on the surface of the pores of the stone, which partially fills the pore space and, being hydrophobic, reduces the water absorption of samples by 2–3 times, and the water absorption of samples impregnated under vacuum for 0.5 hours, decreases to values of 1.3–1.9%. Results and discussion. Modification of concrete with an impregnating composition developed by us with a solution based on potassium polysulfide The impregnating solution based on potassium polysulfide is stable in the concentration range of 1.15–1.35 g/cm3; upon impregnation, it penetrates into the pore structure of concrete at a level of up to 4 cm or more, depending on the growth and structure of the sample. When the material dries in its pores, sulfur nanoparticles crystallize from the polysulfide solution, partially filling the pore space and forming a protective durable insoluble hydrophobic coating that makes it difficult for water to penetrate into the pores of concrete, but retains its vapor permeability, which is important for wall and facing materials. Conclusions. Impregnation of road building materials and concrete products with a composition based on potassium polysulfide improves their performance properties, increases durability and resistance to weathering, which makes it possible to recommend it for use in the climatic conditions of the Russian Federation.

53–58

Authors: Nazarov V.G., Dedov A.V., Bokova E.S.

ABSTRACT: Introduction. The aim of the research is to study the compressibility of composite materials obtained by varying the degree of impregnation of a non-woven needle-punched cloth with an aqueous dispersion of polyurethane. Materials and research methods. Non-woven needle-punched cloth made of polyethylene terephthalate fibers (TU 6-13-0204077-95-91) with a linear density of 0.33 tex (diameter 20–25 microns) was used as objects of research. For impregnation, an aqueous dispersion of anionic stabilized aliphatic polyethiruretane of the brand IMPRANIL DL 1380 (PRC) with a dry residue of 40% was used. The ompressibility of canvases and composite materials was established using the ICH indicator according to GOST 577-68 with an accuracy of measuring the thickness of ± 0.001 mm. Results and discussion. An approach is proposed to establish the relationship between the degree of compressibility of composite materials and the load and to obtain an equation for predicting the degree of compressibility of composite materials from the degree of impregnation and load. Optimal loading conditions of the composite material with a minimum degree of compressibility has been established. Сonclusion. The optimal degree of impregnation of a non-woven needlepunched fabric made of polyethylene terephthalate fibers with a diameter of 20–25 microns with polyurethane dispersion is 0.5.

72–83

Authors: Gorbatova V.N., Gordeeva I.V., Dudareva T.V., Krasotkina I.A., Nikol'skii V.G., Egorov V.M.

ABSTRACT: Introduction. In the article the use of powder elastomeric modifier capable of rapid breakdown into micro- and nanofragments upon contact with hot bitumen to improve the low-temperature properties of bitumen is presented. The indicators of resistance to cracking are determined by various methods and their dependence on the thermal history of the samples. Methods and Materials. At temperatures up to –36о C the oscillatory rheological tests (4-mm DSR test) of RTFO-aged samples of bitumen BND 60/90 and modified binder (MB) which contain the active powder of discretely devulcanized rubber (APDDR) produced by high-temperature shear-induced grinding from the crumb rubber of worn tires have been conducted. MB was prepared by mixing bitumen (3 min; 160о C and 600 rpm) with 12.5 wt.% APDDR. Results and Discussion. The effect of the test parameters on the rheological parameters has been studied. Structural transitions in bitumen and MB by methods of differential scanning calorimetry (DSC) and the cracking temperature of the same samples in static conditions in the ABCD test were detected. It is revealed: a decrease in the temperature of actual cracking of the MB sample compared to bitumen. Conclusion. It is shown that APDDR as a modifier affects the structure of bitumen and reduces the temperature sensitivity of bitumen to external influences.