Zaštita patine na bronci polimernim nanoprevlakama

master's thesis

• Title (english): Protection of bronze patina with polymer nanocoatings
• Author: Barbara Markulić
• Mentor: Marijana Kraljić Roković (mentor)
• Mentor: Katarina Marušić (komentor)
• Committee member: Marijana Kraljić Roković (predsjednik povjerenstva)
• Committee member: Elvira Vidović (član povjerenstva)
• Committee member: Katarina Marušić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-06-20, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Umjetnička djela i kulturna baština od bronce, izloženi su svakodnevnim onečišćenjima prisutnim u otvorenoj ili zatvorenoj atmosferi. Stoga su podložni korozijskim procesima koji mogu dovesti do promjena u njihovom izgledu i stabilnosti te do propadanja materijala koji zatim uzrokuju materijalne troškove popravka ili zamjene. Takvi objekti su često prekriveni patinom, koja ima estetsku i/ili povijesnu vrijednost. Patina na brončanim skulpturama također štiti osnovni metal samog umjetničkog predmeta. Cilj ovog rada bio je ispitati mogućnost zaštite bronce i njezine patine od korozije uzrokovane kiselim kišama, primjenom neumreženih i umreženih samoorganizirajućih monoslojeva behenske kiseline. Ispitivanja su provedena u otopini koja simulira kiselu kišu pri pH 5. Behenska kiselina, C21H43COOH, također poznata kao dokozanska kiselina pripada dugolančanim zasićenim masnim kiselinama. Uzorci su zračeni na panoramskom izvoru 60Co gama zračenja s ciljem induciranja umrežavanja samoorganiziranog sloja behenske kiseline. Stabilnost dobivenih prevlaka u simuliranoj kiseloj kiši proučavana je elektrokemijskim metodama (metoda Tafelove ekstrapolacije i elektrokemijska impedancijska spektroskopija), dok su površine karakterizirane pretražnim elektronskim miskroskopom (SEM), Raman spektroskopijom i metodom mjerenja kontaktnog kuta. Dobiveni rezultati pokazali su da najveću otpornost na koroziju ima uzorak čiste bronce prekriven umreženom prevlakom. Kod uzoraka zelene patine prekrivene PNC-om vidljiva je najbolja kratkoročna zaštita od korozije. Nakon zračenja u UV komori primijećeno je da kod uzoraka prekivenima neozračenom behenskom kiselinom dolazi do degradacije prevlake dok uzorci prekriveni ozračenim filmom ostaju postojani.

Abstract (english)

Works of art and cultural heritage made of bronze are exposed to everyday pollution present in an open or closed atmosphere. Therefore, they are subject to corrosion processes that can lead to changes in their appearance and stability as well as material deterioration, resulting in material costs for repair or replacement. Such objects are often covered with a patina that has aesthetic and/or historical value. The patina on bronze sculptures protects the base metal of the art object itself. The aim of this work was to investigate the possibility of protecting bronze and its patinat from corrosion caused by acid rain by self-assembled molecular layers of behenic acid. The tests were carried out in a solution simulating acid rain at pH 5. Behenic acid, C21H43COOH, also known as docosanoic acid, belongs to the long-chain saturated fatty acids. The samples were irradiated at a panoramic 60Co gamma irradiation source with the aim of inducing crosslinking of behenic acid self-assembled molecular layers. The stability of the obtained coatings in simulated acid rain were studied by electrochemical methods (Tafel extrapolation method and electrochemical impedance spectroscopy ), while the surfaces were characterization by Scanning electron microscope (SEM), Raman spectroscopy and contact angle measurements. The obtained results showed that the pure bronze sample covered with a cross-linked coating has the highest resistance to corrosion. The green patina samples covered with PNC show the best short-term corrosion protection. After irradiation in the UV chamber, it was observed that the coating was degraded in the samples covered with non-irradiated behenic acid, while the samples covered with the irradiated film remained stable.

• Keywords: bronca; patina; samoorganizirajući molekularni slojevi; radijacijsko umrežavanje; polimerne nanoprevlake; gama zračenje; korozija
• Keywords (english): bronze; patina; self-assembled molecular layers; radiation induced crosslinking; polymer nanocoatings; gamma irradiation; corrosion
• Language: croatian
• URN:NBN: urn:nbn:hr:149:372896
• Project: Number: IP-2020-02-4344; Title: Primjena ionizirajućeg zračenja za dobivanje polimernih nano prevlaka na metalima; Title: Irradiated Polymer Nano-Coatings for Metal Protection; Acronym: RadMeNano; Leader: Katarina Marušić; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Research Projects
• 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: 2024-07-02 10:49:25