The supramolecular impact mechanism of polycarboxylate superplasticizers on controlled hardening construction of nanocomposites

Автор: Khalikov R.M., Ivanova O.V., Korotkova L.N., Sinitsin D.A.

Журнал: Nanotechnologies in Construction: A Scientific Internet-Journal @nanobuild-en

Рубрика: System resolutions to technological problems

Статья в выпуске: 5 Vol.12, 2020 года.

Бесплатный доступ

Introduction. The use of modifying nano-additives in the production of binding building materials is one of the most effective ways to control the technological parameters of concrete by conducting good control of the rheological characteristics reliability. Plasticizing additives increase the water-holding capacity of building compositions, which leads to the dispersed nanosystems stability. This article is focused on examining the physical and chemical mechanisms of the supramolecular effects of polycarboxylate ethers on technological and rheological characteristics of cement nanobinders. Methods and materials. This study describes controlled hardening processes of concrete nanocompositions with demanded technological characteristics in the presence of highly effective plasticizers. Moreover, this paper carries out the analysis of the innovative trends in regulating the consistency of building nanocomposites with the use of new comb-like polycarboxylate esters, which as superplasticizers allow to purposefully influence the kinetics of structure formation of cement nanocomposites. Results. Electrostatic and steric repulsion mechanisms, as well as the dispersing effects of innovative and traditional plasticizing nanoparticles, affect the adsorption and diffusion layers of the hydrated cement nanobinders ultrastructure. The most effective plasticizing properties are shown by comb-like polycarboxylate esters (CPE) with a linear chain molecular weight of ≈12000 g/mol and a length of side branches which correspond to a molecular weight of ≈750 g/mol. The supramolecular mechanism of nanosteric van der Waals repulsive forces begins to be detected at a distance of ≈11 nm, and the elasticity of the lateral branches of innovative CPE is ≈ 5 nm. Individual segments of CPE macromolecules enter the diffuse layer of dispersed nanosystems due to lateral interactions of anions of functional groups, hydrophobic fragments, etc.; they enhance the plasticizing effect of cement binders in concrete nanocompositions. Discussion. When using superplasticizing CPE, the density of concrete nanocomposites can be increased by reducing the amount of water mass to the cement mass ratio to the optimal 0.3; at the same time, technological pumpability and reliability control of the joint hardening kinetics with fillers are preserved within the framework of the technological problems system solutionsconcept. Supramolecular interaction of «anchoring» functional groups of polyacrylic acid containing solid phase cations of cement microparticles, fractal clusters of calcium hydrosilicates and simultaneous steric stabilization of polyethylene glycol radicals give the necessary rheological characteristics to construction nanocompositions and allow the construction of high-strength 55÷80 MPa building materials. Conclusions. The branched comb-like nanostructure of polycarboxylate esters exhibits effective technological characteristics of superplasticizers for concrete, building mortars and dry building mixes.

Еще

Cement nanobinders, superplasticizers, polycarboxylates, reliability management, concrete structure formation

Короткий адрес: https://sciup.org/142226956

IDR: 142226956   |   DOI: 10.15828/2075-8545-2020-12-5-250-255

Список литературы The supramolecular impact mechanism of polycarboxylate superplasticizers on controlled hardening construction of nanocomposites

  • Chernishov E.M., Artamonova O.V., Slavcheva G.S. Nanomodification of cement-based composites in the technological life cycle. Nanotechnologies in Construction. 2020; 12 (3): 130–139. Available from: doi: 10.15828/2075-8545-2020-12-3-130-139.
  • Bullard J.W., Jennings H.M., Livingston R.A. et al. Mechanisms of cement hydration.Cement and Concrete Research. 2011; 41(12): 1208–1223. Available from: doi: 10.1016/j.cemconres.2010.09.011.
  • Gasiev A.A., Beppaev Z.U., Khasauov Yu.M. Research of dynamics and level of strength set of concrete laid in steel fixed formwork.Construction mechanics of engineering structures. 2015; 6: 70–76.(In Russian).
  • Afanasiev G. A. Preservation of technological and rheological properties of concrete mixtures during transportation, feeding and laying in formwork systems.Technologies of concrete. 2018;5–6: 32–35.(In Russian).
  • Zhuravleva M.I., Ivanova O.V., Khalikov R.M. Management of technological characteristics of binding materials with polycarboxylate superplasticizers. In: Comp. XII International Conf. “Actual problems of science and technology-2019”. Vol. 2. Ufa: Publishing house ≪USPTU≫, 2019. p. 111–113. (In Russian).
  • Paul S.C., Rooyen A.S., Gideon P.A. et al. Properties of cement – based composites using nanoparticles: A comprehensive review.Construction and Building Materials. 2018; 189: 1019–1034. Available from: doi: 10.1016/j.conbuildmat.2018.09.062.
  • Alenichev M.K., Drozhzhennikova E.B., Levin A.D., Nagaev A.I. Patent 2714751 RU IPC C1. Method for evaluating the aggregation of nanoparticles in colloidal solutions. 2020. No. 5.(In Russian).
  • Minakov Yu.A., Kononova O.V., Anisimov S.N., Gryazina M.V. Control of concrete hardening kinetics at negative temperatures. Fundamental research. 2013; 4–2: 307–311.(In Russian).
  • Bogdanov R.R., Pashaev A.V., Zhuravlev M.V. Influence of plasticizing additives based on polycarboxylate ether and polyaryl on the physical and technical properties of cement compositions. Bulletin of the technological University. 2018; 21(11): 45–49.(In Russian).
  • Sivtsov E.V., Gostev A.I., Rodionova V.D. et al. Synthesis and properties of superplasticizers of cement mixtures based on acrylic acid copolymers with methoxypolyethylene glycol methacrylates. Izvestia of the Saint Petersburg State technological Institute (Technical University). 2018; 47: 50–56. (In Russian).
  • Yamada K. Basics of analytical methods used for the investigation of interaction mechanism between cements and superplasticizers. Cement and Concrete Research. 2011; 41: 793–798.
  • Sinitsin D.A., Khalikov R.M., Bulatov B.G. et al. Technological approaches to directed structure formation of construction nanocomposites with increased corrosion resistance. Nanotechnologies in Construction. 2019; 11(2): 153–164. Available from: doi: 10.15828/2075-8545-2019-11-2-153-164.
  • Dalas F., Pourchet S., Rinald D. et al. Modification of the rate of formation and surface area of ettringite by polycarboxylate ether superplasticizers during early C3A–CaSO4 hydration.Cement and Concrete Research. 2015; 69: 105–113. Available from: doi: 10.1016/j.cemconres.2014.12.007.
  • Ivanov L.A., Kapustin I.A., Borisova O.N., Pisarenko Zh.V. Nanotechnologies: a review of inventions and utility models. Part II. Nanotechnologies in Construction. 2020; 12(2): 71–76. Available from: doi: 10.15828/2075- 8545-2020-12-2-71-76.
  • Skripkyunas G., Yakovlev G.I., Karpova E.A. et al. Changes in the rheological properties of nanomodified cement systems over time. Industrial and civil construction. 2017; 2: 43–50. (In Russian).
  • Samchenko S.V., Zemskova O.V., Kozlova I.V. Model and mechanism of stabilization of carbon nanotubes with a polycarboxylate-based plasticizer. Vestnik MSBU. 2017; 12(7): 724–752. (In Russian).
  • Khalikov R.M., Sinitsina E.A., Silantyeva E.I.et al. Modifying intensification of the hardening of extruded construction gypsum nanocomposites. Nanotechnologies in Construction. 2019; 11(5): 549–560. Available from: doi: 10.15828/2075-8545-2019-11-5-549-560.
  • Mikhailova N.N., Krasko S.A., Bogomazova A.A., Shavshukova S.Yu. Basic heterocyclic and bioorganic compounds. Ufa: USPTU, 2013. 98 p. (In Russian).
  • Zotkin A.G. Criteria for the effectiveness of superplasticizers in concrete. Technologies of concrete. 2017; 3–4: 31–35. (In Russian).
  • Slavcheva G.S., Artamonova O.V. The rheological behavior of disperse systems for 3D printing in constrcution: the problem of control and possibility of ≪nano≫ tools application. Nanotechnologies in Construction. 2018; 10(3): 107–122. Available from: doi: 10.15828/2075-8545-2018-10-3-107-122. (In Russian).
  • Ivanova O.V., Korotkova L.N., Khalikov R.M. Innovative approaches to quality management of plasticizing additives creation. Comp. 10th All-Russian Conf. “Modern innovations in science and technology”. Kursk: SWSU, 2020. p. 131–134. (In Russian).
  • Sinitsin D.A., Babkov V.V., Sahibgareev R.R. et al. Application of self-compacting concrete mixes in the construction practice of the Republic of Bashkortostan. Construction Materials. 2019;12: 45–51. Available from: doi: 10.31659/0585-430X-2019-777-12-45-51. (In Russian).
  • Khalikov R.M., Ivanova O.V. Technological schemes for solving environmental problems of regional production of materials. Nauka-Rastudent.ru. 2014; 3(03): 10. (In Russian).
  • Chernishov E.M., Artamonova O.V., Slavcheva G.S. Nanotechnological applied tasks of the increase in the efficiency of the hardening processes of cement concrete. Nanotechnologies in Construction. 2017; 9(1): 25–41. Available from: doi: 10.15828/2075-8545-2017-9-1-25-41. (In Russian).
  • Gusev B.V. Concrete with fillers of various dispersion and their nanomodification. Nanotechnologies in Construction. 2019; 11(4): 384–393. Available from: doi: 10.15828/2075-8545-2019-11-4-384-393.
Еще
Статья научная