Impedancijsko ispitivanje zaštitnih svojstava viskoelastične prevlake na čeliku novom ćelijom s elektrolitskom pastom

master's thesis

• Title (english): Assessment of protective properties of viscoelastic coating on steel by the novel paste electrolyte cell
• Author: Karla Korda
• Mentor: Sanja Martinez (mentor)
• Committee member: Sanja Martinez (predsjednik povjerenstva)
• Committee member: Jozefina Katić (član povjerenstva)
• Committee member: Iva Movre Šapić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-02-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

U okviru ovog rada bilo je potrebno ispitati zaštitna svojstva komercijalne viskoelastične prevlake na osnovi poliizobutilena nanesene na površinu čelika. Metoda korištena za ispitivanje je elektrokemijska impedancijska spektroskopija, primjenom ReCorr® QCQ uređaja. Uz jednostavnost nanošenja i ekološku prihvatljivosti prevlake, impedancijska ispitivanja provedena na neoštećenom uzorku ukazuju na izvrsna zaštitna svojstva prevlake. U svrhu ispitivanja zaštitnih svojstava prevlake u neidealnim uvjetima, uzorak je mehanički oštećen, a impedancijski ispitivanja su pokazala da prevlaka na neoštećenim dijelovima i dalje pruža izvrsnu zaštitu od korozije. Nadalje, impedancijska mjerenja su provedena na mehanički oštećenom uzorku koji je prethodno izložen uvjetima 100 %-tne vlažnosti te na uzorku koji je izložen 3,5 %-tnoj otopini NaCl. Rezultati ispitivanja ukazali su na to da prevlaka ima loša zaštitna svojstva u prisustvu mehaničkih oštećenja koja prodiru do površine čelika, ali pokazuje izvrsna zaštitna svojstva pri mehaničkim oštećenjima koja ne prodiru do površine čelika. Osim toga, bilo je potrebno odrediti vodoupojnost prevlake upotrebom rezultata impedancijskih mjerenja nakon izlaganja uzorka vlažnim i slanim uvjetima te dobivene rezultate usporediti s rezultatima iz literature. Iz rezultata je vidljivo da prevlaka pokazuje veću vodoupojnost pri izlaganju vlažnim uvjetima nego pri izlaganju slanim uvjetima. Primjena EIS metode korištenjem ReCorr® QCQ uređaja pokazala se kao jednostavna i praktična metoda za ispitivanje zaštitnih svojstava viskoelastične prevlake. Također omogućava potvrdu značaja okolišnih uvjeta i vrste oštećenja za zaštitna svojstva prevlake.

Abstract (english)

The task of this paper was to test the protective properties ofcommercial polyisobutylene-based viscoelastic coating applied to the steel surface. The method used for testing is electrochemical impedance spectroscopy, using the ReCorr® QCQ device. In addition to easy application and environmental acceptability of the coating, impedance tests performed on undamaged sample indicate excellent protective properties of the coating. In order to examine the protective properties of the coating under non-ideal conditions, the sample was mechanically damaged, and impedance results showed that the coating on undamaged parts still provides excellent protection against corrosion. Furthermore, impedance measurements were performed on a mechanically damaged sample that was previously exposed to conditions of 100 % humidity and on a sample that was exposed to a 3,5 % NaCl solution. Test results indicated that the coating has poor protective properties in the presence of mechanical damage that penetrates to the steel surface, but shows excellent protective properties in the presence of mechanical damage that does not penetrate to the steel surface. Also it was necessary to determine the water uptake of the coating using the results of impedance measurements after exposing the sample to humid and salt conditions, and to compare the obtained results with the results from the literature. It is evident from the results that the coating shows higher water uptake when exposed to humid conditions than when exposed to salt conditions. The application of the EIS method using the ReCorr® QCQ device proved to be a simple and practical method for testing the protective properties of the viscoelastic coating. It also enables confirmation of the importance of environmental conditions and the type of damage for the protective properties of the coating.

• Keywords: viskoelastična prevlaka; EIS; vodoupojnost; mehaničko oštećenje
• Keywords (english): viscoelastic coating; EIS; water uptake; mechanical damage
• Language: croatian
• URN:NBN: urn:nbn:hr:149:892264
• Study programme: Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra primijenjene kemije (sveučilišni/a magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-02-29 10:14:06