Utjecaj modifikacije TiO2 na svojstva poliakrilatnih sustava

master's thesis

• Title (english): Influence of TiO2 modification on the properties of polyacrylate systems
• Author: Kristina Ivić
• Mentor: Sanja Lučić Blagojević (mentor)
• Committee member: Sanja Lučić Blagojević (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Vesna Ocelić Bulatović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2018-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Polimeri na bazi akrilata (PAK) imaju široku primjenu u proizvodnji boja, premaza, adheziva i sl. Nanočestice titanijevog dioksida mogu djelovati kao UV apsorberi, one se dodaju premazima na bazi poliakrilata kako bi poboljšali svojstva tako dobivenog zaštitnog premaza koji se koristi u raznim industrijama, poput drvne. Korištenje nanopunila za poboljšanje svojstava polimera dovelo je do razvoja polimernih nanokompozita koji imaju jedinstvena mehanička, električna, optička, kemijska i magnetska svojstva. Preduvjet za postizanje nanokompozita s poboljšanim svojstvima je dobra dispergiranost i raspodjeljenost nanopunila u polimernoj matrici. U ovom radu sintetizirana je poliakrilatna (PAK) emulzija te PAK/TiO2 emulzije s 1 % TiO2 punila postupkom in situ emulzijske polimerizacije. Kako bi se ispitao utjecaj modifikacije površine punila na svojstva dobivenih emulzija i filmova pripravljenih iz emulzija, površina TiO2 nanopunila modificirana je različitim vrstama silana, kationskim inicijatorom (AIBA) te neionskim emulgatorom (NE). PAK/TiO2 emulzijama su određivana reološka svojstva. Karakterizacija pripravljenih filmova bila je usmjerena na određivanje morfologije i mehaničkih svojstava filmova, te toplinskih svojstava filmova diferencijalom pretražnom kalorimetrijom (DSC) i termogravimetrijskom analizom (TGA). Rezultati su pokazali da modifikacija punila značajno povećava viskoznost PAK emulzije. Modifikacijom površine TiO2 punila dobije se ravnomjernija raspodjela punila unutar polimerne matrice u odnosu na sustav s nemodificiranim punilom. PAK i PAK/TiO2 filmovi pokazuju dva staklišta, a utjecaj punila očituje se u promjeni Tg1. Dodatak nemodificiranog i modificiranog punila PAK matrici u kasnijim stadijima toplinske razgradnje pomiče temperature razgradnje PAK matrice na više vrijednosti. Prekidno istezanje PAK/TiO2 filmova je više u odnosu na prekidno istezanje čistog PAK filma.

Abstract (english)

Acrylic based polymers (PA) are widely used in the manufacture of paints, coatings, adhesives etc. Since titanium dioxide can act as UV absorber, TiO2 is often added in polyacrylate coatings to improve PA usage as a protective coating in a different industries for instance wood industry. The use of nanofiller has led to the development of polymeric nanocomposites which have unique mechanical, electrical, optical, chemical and magnetic properties. To prepare nanocomposite with improved properties homogeneous dispersion of the filler in the polymer matrix has to be achieved. In this work polyacrylate (PA) emulsion and PA/TiO2 emulsions with 1 % TiO2 filler by in situ emulsion polymerisation process was prepared. In order to investigate the effect of filler surface modification on the properties of the PA emulsion and films obtained from the emulsion the surface of TiO2 nanofiller was modified by various types of silane, cationic initiator (AIBA) and nonionic emulsifier (NE). Rheological properties of PA/TiO2 emulsions were determined. Morphology, mechanical and thermal properties (DSC and TGA analysis) of the films were investigated. The results showed that modification of the filler significantly increases the viscosity of the PA emulsion. By modifying the surface of the TiO2 filler, a uniform dispersion of the filler inside the polymer matrix is obtained in relation to the unmodified filler system. PA and PA/TiO2 films show two glass transition temperatures and the influence of the filler is reflected in the change of Tg1. The addition of unmodified and modified TiO2 filler to PA matrix, at later stages of thermal degradation, displaces the degradation temperature of the PA matrix to higher values. Elongation at break of the PA/TiO2 films is higher than elongation of the pure PA film.

• Keywords: poliakrilati; TiO2; in situ emulzijska polimerizacija; reologija; morfologija; DSC; TGA; mehanička svojstva
• Keywords (english): polyacrylates; TiO2; in situ emulsion polymerization; rheology; morphology; DSC; TGA; mechanical properties
• Language: croatian
• URN:NBN: urn:nbn:hr:149:052525
• 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: Open access
• Created on: 2020-10-26 13:06:49