Priprema umjetne patine na bronci i njena modifikacija fosfonskim kiselinama

master's thesis

• Title (english): Preparation of artificial patina on bronze and its modification by phosphonic acids
• Author: Nikolina Miličević
• Mentor: Helena Otmačić Ćurković (mentor)
• Committee member: Helena Otmačić Ćurković (predsjednik povjerenstva)
• Committee member: Marijana Kraljić Roković (član povjerenstva)
• Committee member: Tatjana Gazivoda Kraljević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Umjetnička djela i kulturna baština od bronce, izloženi su svakodnevnim onečišćenjima prisutnim u otvorenoj ili zatvorenoj atmosferi. S obzirom na to, oni su podložni korozijskim procesima koji mogu dovesti do promjena u njihovom izgledu i stabilnosti te do kroničnog propadanja materijala koji zatim uzrokuju materijalne troškove popravka ili zamjene. Takvi objekti su stoga često prekriveni patinom, koja ima estetsku i/ili povijesnu vrijednost. Patina na brončanim skulpturama štiti osnovni metal te poboljšava estetiku samog umjetničkog predmeta. Jedna od mogućnosti zaštite brončanih površina je modifikacija površine tankim filmom organskih molekula. Cilj ovog rada bio je ispitati mogućnost zaštite patinirane bronce od korozije uzrokovane kiselim kišama, primjenom samoorganizirajućih monoslojeva dugolančanih fosfonskih kiselina. Ispitivanja su provedena u otopini koja simulira kiselu kišu pri pH 5. Uspoređivana su svojstva netretiranih i tretiranih površina pri različitim uvjetima koji utječu na formiranje samoorganizirajućeg monosloja i različitim metodama nanošenja zaštite. Zaštitno djelovanje dobivenih tankih filmova potvrđeno je elektrokemijskim ispitivanjima, metodama linearne polarizacije te elektrokemijskom impedancijskom spektroskopijom. Kako bi se dobile kvalitativne i kvantitativne informacije o dobivenom zaštitnom sloju, također se provela analiza Fourier transformacijskom infracrvenom spektroskopijom. S obzirom na dobivene rezultate, potvrđeno je postojanje i djelotvornost zaštitnog filma 16 – fosfonoheksadekanoične kiseline na patiniranoj bronci stupanj i trajnost dobivene zaštite značajno ovise o uvjetima i načinu pripreme zaštitnog filma.

Abstract (english)

Bronze art works and cultural heritage are exposed to everyday pollution present in outdoor or indoor atmosphere. Because of that, they are subjected to corrosion processes that can lead to changes in their appearance and stability and chronic decay of material, which then cause material repair or replacement costs. Such objects are therefore often covered with patina, which has aesthetic and / or historical value. Patina on bronze sculptures protects the base metal and enhances the aesthetics of the artwork itself. One of the possibilities of protecting bronze surfaces is the modification of the surface with a thin film of organic molecules. The aim of this study was to examine the possibility of protecting patinated bronze from corrosion caused by acid rain, using self-assembled monolayers long-chain phosphonic acids. Tests were conducted in a solution that simulates acid rain at pH 5. The properties of untreated and treated surfaces under different conditions affecting the formation of self-assembled monolayers and various protection methods have been compared. The protective effect of the obtained thin films was confirmed by electrochemical assays, linear polarization method and electrochemical impedance spectroscopy. In order to obtain qualitative and quantitative information on the obtained protective layer, a Fourier transformation infrared spectroscopy was also performed. Given the results obtained, the existence and effectiveness of the protective film of 16-phosphonohexadecanoic acid on patinated bronze has been confirmed. The durability of the obtained protection significantly depends on the conditions and method of preparation of the protective film.

• Keywords: brončani spomenici; patina; kisela kiša; samoorganizirajući monoslojevi; fosfonska kiselina
• Keywords (english): bronze monuments; patina; acid rain; self – assembled monolayers; phosphonic acid
• Language: croatian
• URN:NBN: urn:nbn:hr:149:814639
• Study programme: Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Applied organic chemistry; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra primijenjene kemije (magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-04-27 10:32:02