Utjecaj položaja dvostruke veze u masnoj kiselini samoorganiziranoj na bakru na umrežavanje primjenom ionizirajućeg zračenja

master's thesis

• Title (english): Influence of double bond position in self-assembled fatty acids on copper on crosslinking using ionizing radiation
• Author: Nora Čobanov
• Mentor: Marijana Kraljić Roković (mentor)
• Mentor: Katarina Marušić (komentor)
• Committee member: Marijana Kraljić Roković (predsjednik povjerenstva)
• Committee member: Katarina Marušić (član povjerenstva)
• Committee member: Sanja Lučić Blagojević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2022-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Cilj ovog rada bio je ispitati utjecaj položaja dvostruke veze u masnoj kiselini samoorganiziranoj na bakru na zaštitna svojstva gama zračenjem umreženih nano prevlaka. Masne kiseline korištene za samoorganizaciju su elaidinska kiselina, EA, C18H34O2, i transvakcenska kiselina, VA, C18H34O2, nezasićene masne kiseline sa 18 C atoma i jednom dvostrukom vezom u trans položaju. EA ima dvostruku vezu na 9. C atomu, a VA na 11. Masene kiseline se spontano samoorganizira na bakru u slojeve visokog stupnja uređenosti. U radu je korištena metoda uranjanja. Jednom posložene molekule na površini bakra umrežavaju se preko dvostruke veze primjenom gama zračenja te nastaju umrežene 3D strukture. Polimerizacijom masnih kiselina se poboljšavaju kemijska i fizikalna svojstva samoorganiziranih prevlaka. Pomoću elektrokemijskih metoda (elektrokemijska impedancijska spektroskopija (EIS) i metoda Tafelove ekstrapolacije) su provedena ispitivanja zaštitnih svojstava razvijenih prevlaka. Goniometrija i infracrvena spektrometrija s Fourierovom transformacijom signala (FTIR) su korištene za karakterizaciju razvijenih prevlaka. Optimalna doza zračenja za EA je od prije poznata i iznosi 110 kGy, a za VA je određivana u ovome radu te je utvrđeno da je 150 kGy. VA je pokazala malo bolja zaštitna svojstva od EA, ali je vrlo velika razlika između potrebnih doza zračenja za uspješno umrežavanje, čak 40 kGy. Pošto su VA i EA strukturalno vrlo slične ovi rezultati su iznenađujući. Pretpostavljamo da je greška u komercijalnoj masnoj kiselini te je zato potrebna tako velika doza zračenja za umrežavanje VA.

Abstract (english)

The aim of this work was to investigate the influence of the position of the double bond in a fatty acid self-assembled on copper on the protective properties of nano coatings crosslinked by gamma radiation. The compounds used for self-assembly in this work were elaidic acid, EA, C18H34O2, and trans-vaccenic acid, VA, C18H34O2, unsaturated fatty acids with 18 C atoms and one double bond in the trans position. EA has a double bond at the 9th C atom and VA at the 11th position atom. Fatty acids spontaneously self-assemble on copper into highly ordered layers. The immersion method was used in this work. Molecules once arranged on the surface of copper are cross-linked via a double bond using gamma radiation, and cross-linked 3D structures are formed. Polymerization of fatty acids improves thechemical and physical properties of the developed coatings. Using the electrochemical methods (electrochemical impedance spectroscopy (EIS) and Tafel extrapolation method), studies of the protective properties of the developed coatings were performed. Goniometry and Fourier transform infrared spectrometry (FTIR) were used to characterize the developed coatings. The optimal irradiation dose for EA is known from previous studies and is 110 kGy, while for VA it was determined as 150 kGy in this work. VA shows slightly better protective properties, but there is a very large difference between the irradiation doses needed for successful crosslinking, as high as 40 kGy. Since VA and EA are structurally very similar these results are surprising. We assume that the problem was in the commercial fatty acid, and that is why such a high dose of radiation is needed to crosslink the VA.

• Keywords: ionizirajuće zračenje; masne kiseline; korozija; bakar; umrežavanje
• Keywords (english): ionizing radiation; fatty acids; corrosion; copper; crosslinking
• Language: croatian
• URN:NBN: urn:nbn:hr:149:564113
• 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: HRZZ; Funding stream: IP
• 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: magistar/magistra primijenjene kemije (magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2023-03-31 12:12:47