Izbor duljine lanca i konformacije nezasićene masne kiseline za postizanje optimalnih zaštitnih svojstava polimernih nano prevlaka

master's thesis

• Title (english): Selection of chain length and conformation of unsaturated fatty acids to achieve optimal protective properties of polymer nano coatings
• Author: Jelena Vrhovec
• Mentor: Helena Otmačić Ćurković (mentor)
• Mentor: Katarina Marušić (komentor)
• Committee member: Helena Otmačić Ćurković (predsjednik povjerenstva)
• Committee member: Marijana Kraljić Roković (član povjerenstva)
• Committee member: Katarina Marušić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2022-09-23, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Cilj ovog rada bio je odrediti utjecaj duljine lanca i konformacije nezasićene masne kiseline na zaštitna svojstva polimernih nano prevlaka na bakru. Prevlake su formirane na bakru u obliku samoorganizirajućih monoslojeva (SAM-ova). Spojevi korišteni za formiranje prevlaka su oleinska, OL, (C18H34O2), elaidinska, EA, (C18H34O2) i 11-eicoscenic kiselina, 11-E, (C20H38O2), a za njihovo nanošenje na površinu bakra koristila se metoda uranjanja. Umrežavanje monoslojeva inicirano je primjenom ionizirajućeg gama zračenja kod različitih absorbiranih doza, ovisno o ispitivanoj kiselini. Za OL i EA kiselinu ispitani su neozračeni uzorci i uzorci ozračeni sa 110 kGy, dozom koja je ranijim ispitivanjima određena kao optimalna za te kiseline, dok su za 11-E uz neozračene uzorke ispitani i uzorci ozračeni dozama u rasponu od 90 do 170 kGy. Zaštitna svojstva polimernih nano prevlaka ispitana su elektrokemijskim metodama i karakterizacijom površine. Za karakterizaciju površine korištene su goniometrija i infracrvena spektroskopija s Fourierovom transformacijom signala (FTIR). Od elektrokemijskih metoda korištene su metoda Tafelove ekstrapolacije i elektrokemijska impedancijska spektroskopija (EIS). Dobiveni rezultati pokazali su da su optimalna zaštitna svojstva ostvarena na uzorcima s prevlakama EA ozračenima sa 110 kGy. Metodom Tafelove ekstrapolacije pokazano je da se kod ovih uzoraka postiže najniža vrijednost gustoće korozijske struje, a metodom EIS da uzorci s EA prevlakama ozračeni sa 110 kGy postižu najveće vrijednosti apsolutne impedancije, otpora prijenosu naboja i otpora filma. Mjerenjem kontaktnog kuta također je najbolji rezultat ostvaren kod ovih uzoraka, odnosno postignuta je najveća hidrofobnost površine bakra. Analizom rezultata FTIR-a potvrđeno je da su prevlake masnih kiselina na bakru postojane i nakon zračenja.

Abstract (english)

The goal of this thesis was to determine the influence of the chain lenght and conformation of an unsaturated fatty acid on the protective properties of polymer nano coatings on copper. The coatings were formed on copper in the form of self-assembling monolayers (SAM) using the immersion method. Compounds used for the coating formation were oleic, OL, (C18H34O2), elaidic, EA, (C18H34O2) and 11-eicoscenic acid, 11-E, (C20H38O2). Monolayers' crosslinking was initiated with the application of ionising gamma radiation of different doses, depending on the acid in question. In the case of OL and EA acid, measurements were performed on non-irradiated and samples irradiated with a dose of 110 kGy, whereas for the 11-E samples the same measurements were performed on non-irradiated and samples irradiated with doses in the range from 90 to 170 kGy. The protection properties of the studied polymer nano coatings were tested by electrochemical measurements and by sufrace characterization. Goniometry and infrared spectroscopy with Fourier signal transformation (FTIR) were used for surface characterization. Electrochemical methods used were Tafel extrapolation method and electrochemical impedance spectroscopy (EIS). The obtained results showed that the optimal protection properties were accomplished on samples of EA irradiated with a dose of 110 kGy. Tafel extrapolation method showed that these samples have the lowest value for corrosion current density, and the EIS method showed that EA samples irradiated with a dose of 110 kGy have the highest values of absolute impedance, resistance to charge transfer and film resistance. Contact angle measurements also showed that the best results were achieved for these samples, meaning the highest hydrophobicity of the copper surface. FTIR results analysis confirmed that fatty acid coatings on copper are stable after applied irradiation.

• Keywords: gama zračenje; SAM; polimerne nano prevlake; elaidinska kiselina; oleinska kiselina; 11-eicoscenic kiselina; bakar; EIS; FTIR
• Keywords (english): gamma irradiation; SAM; polymer nano coatings; elaidic acid; oleic acid; 11-eicoscenic acid; copper; EIS; FTIR
• Language: croatian
• URN:NBN: urn:nbn:hr:149:849334
• 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: Chemical Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-03-23 10:39:24