“Smart” anticorrosion pigment based on layered double hydroxide: construction and characterization
Journal Title: Восточно-Европейский журнал передовых технологий - Year 2019, Vol 4, Issue 12
Abstract
<p>Paint coatings are widely used for decorative purposes and to prevent corrosion of metal surfaces. However, regular paint coating only provides passive protection of the metal. To create an active type of corrosion protection, various anti-corrosion additives are added to paint formulations. As a result of analyzing available data, a bi-functional (colored and anti-corrosion) pigment was theoretically constructed as monophase Zn-Al-tripolyphosphate LDH with the generalized formula Zn<sub>0.8</sub>Al<sub>0.2</sub>(P<sub>3</sub>O<sub>10</sub>)<sub>0.04</sub>. In this LDH, Zn<sup>2+</sup> as “host” cation and Al<sup>3+</sup> as “guest” cation govern white color of the pigment, and intercalated tripolyphosphate-anions – corrosion inhibitor. A continuous constant pH synthesis at a temperature of 70°С was selected as a preparation method. This method was used to prepare theoretically constructed pigment. The crystal structure of the pigment sample was studied by means of X-ray diffraction, morphology and particle size were determined by means of scanning electron microscopy, thermal properties were evaluated by means of thermogravimetry. Color characteristics were recorded using the color comparator, anti-corrosion properties were evaluated by recording anodic polarization curves of 08KP steel in 5 % (wt.) Na<sub>2</sub>SO<sub>4</sub> solution with and without the pigment extract. By means of X-ray diffraction analysis, it was found that bi-phase precipitate, containing the constructed LDH (with Zn(OH)<sub>2 </sub>structure) and Zn-Al LDO (ZnO structure) was formed. This indicated partial decomposition of LDH during synthesis, but the reason for it is unknown. By means of SEM, the formation of agglomerates of the same particles with high surface area was found. The study of color characteristics revealed that the prepared pigment has high whiteness value (diffuse reflection coefficient above 90 %, color purity below 1 %, lightness above 96 %). This is due to the color of both LDH and LDO phases. By recording anodic polarization curves, it was found that corrosion rate in the presence of water extract of the pigment is lower by 5.36 times (corrosion current density decreased from 5.63 mA/cm<sup>2</sup> to 1.03 mA/cm<sup>2</sup><sub>.</sub> All of this shows that a bi-functional pigment was prepared, which has great pigment properties, high whiteness, and high anti-corrosion properties.</p>
Authors and Affiliations
Vadym Kovalenko, Valerii Kotok
Influence of the duration of aging the system Ti/Al2O3 in a hydrogen atmosphere on hydrogen sorption, adhesion, tribology, and electrical conductivity of the film
This paper reports results on the interaction between an aluminum oxide film, deposited on technically pure titanium of grade VT1-0 by the magnetron reactive sputtering method, and a hydrogen-containing atmosphere. Such...
Examining the efficiency of electrochemical purification of storm wastewater at machinebuilding enterprises
<p class="a">We have examined the composition of polluted storm water discharged from the territory of a machinebuilding enterprise. It was established that the territory was unevenly polluted, with the surface wastewat...
Analysis of convergence of adaptive singlestep algorithms for the identification of nonstationary objects
<p>The study deals with the problem of identification of non-stationary parameters of a linear object which can be described by first-order Markovian model, with the help of the simplest in computational terms single-ste...
Cryoscopic and microbiological study of the semifinished product for making a smoothie drink
<p class="a">The dynamics of freezing a semi-finished product for making a smoothie drink was investigated. We have chosen, as the subject of present study, a semi-finished product whose production technology included st...
Development of a spatialdynamical model of the structure of clumps of toxic cyanobacteria for biosafty purposes
<p class="a">We have devised a spatialdynamic model that describes the structure of clusters of toxic cyanobacteria over large water areas. The application of the constructed model has been demonstrated in order to iden...