Ispitivanje UV stabilnosti kompozita polietilen niske gustoće/hematit

master's thesis

• Title (english): The study of UV stability of low density polyethylene/hematite composites
• Author: Filip Raguž
• Mentor: Ljerka Kratofil Krehula (mentor)
• Committee member: Ljerka Kratofil Krehula (predsjednik povjerenstva)
• Committee member: Emi Govorčin Bajsić (član povjerenstva)
• Committee member: Helena Otmačić Ćurković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-09-29, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Cilj ovog rada bio je utvrditi učinkovitost zaštite polietilena niske gustoće od ultraljubičastog (UV) zračenja dodatkom hematita (α-Fe2O3) i utjecaj njegovog udjela (0,5 phr, 1,0 phr i 2,0 phr) na strukturu i svojstva polimerne matrice. Uzorci su stareni u UV komori 10 dana, a nakon toga uslijedilo je analiziranje i uspoređivanje rezultata dobivenih infracrvenom spektroskopijom s Fourierovim transformacijama, termogravimetrijskom analizom i vlačnim ispitivanjima. Utvrđeno je da dodatak hematita u polimernu matricu dovodi do zaštite materijala od UV degradacije, povećanja toplinske stabilnosti, povećanja čvrstoće i smanjenja istezljivosti, a u većini slučajeva najboljim se pokazao kompozit s 1,0 phr hematita. Uzimajući u obzir dobivene rezultate i činjenicu da je hematit jeftin, lako dostupan i bezopasan za ljudsko zdravlje i okoliš, hematit bi u budućnosti mogao zamijeniti neke UV apsorbere trenutno u primjeni, stoga bi bilo potrebno provesti daljnja istraživanja i usporediti njihova svojstva.

Abstract (english)

The main goal of this work was to determine the efficiency of using hematite (α-Fe2O3) to reduce the ultraviolet (UV) radiation-induced degradation of low-density polyethylene (LDPE). The work also sought to evaluate how would various concentrations of hematite (0,5 phr, 1,0 phr and 2,0 phr) affect the structure and properties of polyethylene matrix. The samples were weathered in a UV chamber for 10 days and analysed afterwards using Fourier-transform infrared spectroscopy, thermogravimetric analysis and tensile testing. It was determined that, when compared to pure polyethylene, LDPE/hematite composites exhibit lower degrees of photodegradation, greater thermal stability and tensile strength, but also somewhat reduced engineering strain. LDPE/hematite (1,0 phr) composite appears to have the best performance in most instances. Taking these findings into consideration, along with the fact that it is cheap, easily available and harmless to humans and the environment, hematite could replace some UV absorbers currently on the market. Therefore, further testing and performance comparisons may be needed in the future.

• Keywords: fotodegradacija; fotostabilnost; hematit; polietilen; polimerni kompoziti; UV apsorberi
• Keywords (english): photodegradation; photostability; hematite; polyethylene; polymer composites; UV absorbers
• Language: croatian
• URN:NBN: urn:nbn:hr:149:565711
• Study programme: Title: Materials Science and 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: Closed access
• Created on: 2022-04-13 12:26:34