Toplinska svojstva i razgradnja PAK/TiO2 nanokompozita

master's thesis

• Title (english): Thermal properties and degradation of PAK/TiO2 nanocomposites
• Author: Maja Beloša
• Mentor: Sanja Lučić Blagojević (mentor)
• Committee member: Sanja Lučić Blagojević (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Domagoj Vrsaljko (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-09-28, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Vodeni poliakrilatni premazi koriste se kao zaštitni premazi u drvnoj industriji s ciljem usporavanja površinske razgradnje drva. S obzirom da nanočestice titanijevog dioksida mogu djelovati kao UV apsorberi te se dodaju premazima kako bi poboljšali primjenska svojstva takvih zaštitnih premaza. Poliakrilat/TiO2 sustavi sintetizirani su in situ emulzijskom polimerizacijom i ex situ postupkom priprave s koncentracijama koloidne disperzije TiO2 (CCR 200 Mn) od 0,5 %, 0,7 %, 1,0 %, 1,5 %, 2,0 % masenih prema masi monomera. S obzirom na način obrade, korištena su dva različita oblika titanijevog dioksida (CCR 200 Mn i CCR 150) u koncentraciji 0,7 % . Nakon sinteze vodenih poliakrilatnih emulzija, pripravljeni su filmovi koji su zatim izloženi UV zračenju u trajanju od tri tjedna. Prije i poslije izlaganja UV zračenju provedena su istraživanja toplinskih svojstava filmova diferencijalnom pretražnom kalorimetrijom (DSC), termogravimetrijskom analizom (TGA) te im je ispitana toplinska vodljivost. Rezultati su pokazali da TiO2 punilo u sustavima utječe na promjenu temperature staklišta, indukcijsko oksidacijsku temperaturu i toplinsku stabilnost prije i nakon djelovanja UV zračenja. Toplinska svojstva sustava s punilom poboljšana su u odnosu na čistu PAK matricu, što više dolazi do izražaja kod sustava pripravljenih in situ emulzijskom polimerizacijom. In situ emulzijskom polimerizacijom postignuta je bolja dispergiranost punila u poliakrilatnoj matrici. Dodatak punila nije pokazao značajan utjecaj na toplinsku vodljivost i difuzivnost.

Abstract (english)

Water-based polyacrylate coatings can be applied as protective coatings on many kinds of wood products in order to slow down its surface degradation as much as possible. Adding TiO2 nanoparticles to the coating can significantly affect its thermal properties. TiO2 has attracted increased attention in recent years in view of its properties, including intensive UV light absorption. In situ emulsion polymerization and ex situ preparation was used to prepare polyacrylate/TiO2 systems with concentracion of TiO2 colloidal dispersion (CCR 200 Mn) with 0.5 %, 0.7 %, 1.0 %, 1.5 %, 2.0 % mass of filler per mass of monomers. Considering the filler modificatrion, two types of titanium dioxide were used (CCR 200 Mn i CCR 150) in concentration 0.7 %. From prepared water-based polyacrylate emulsions films were prepared and films were exposed to UV radiation for three weeks. Before and after UV exposure the films were characterized by differential scanning calorimetry analysis (DSC), thermogravimetric analysis (TGA) and thermal conductivity was determined. The results showed that TiO2 nanoparticles in polyacrylate systems changed glass transition temperature, oxidation induction temperature and thermal stability before and after UV radiation. Thermal properties of polyacrylate/TiO2 systems are generally improved in relation to polyacrilate without TiO2. Improvement is more pronaunced in systems prepared with in situ emulsion polymerization. Addition of TiO2 nanoparticles has not influence on thermal conductivity and diffusivitty.

• Keywords: premazi; poliakrilati; TiO2; emulzijska in situ polimerizacija; DSC; TGA
• Keywords (english): coatings; polyacrylates; TiO2; in situ emulsion polymerization; DSC; TGA
• Language: croatian
• URN:NBN: urn:nbn:hr:149:530558
• 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: Open access
• Created on: 2020-04-29 12:32:48