Istraživanje starenja i ponašanja mikroplastike nakon ubrzane termodegradacije

master's thesis

• Title (english): Study of aging and microplastic behaviour after accelerated thermodegradation
• Author: Klara Murgić
• Mentor: Zlata Hrnjak-Murgić (mentor)
• Committee member: Zlata Hrnjak-Murgić (predsjednik povjerenstva)
• Committee member: Mirela Leskovac (član povjerenstva)
• Committee member: Nevenka Vrbos (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

U ovom radu simuliran je proces atmosferskog toplinskog starenja polimernog materijala u sušioniku (procesa koji se odvija u okolišu nakon odlaganja plastičnog otpada) kojim nastaje mikroplastika, te je provedena karakterizacija uzoraka nakon simuliranog procesa starenja. U tu svrhu korišteni su komercijalni polimerni materijali: poli(etilen tereftalat) (PET) boce za vodu i PET folije. Starenje je provedeno u nekoliko vremenskih perioda; 14 dana, 28 dana i 42 dana, a svaki dan predstavljao je jedan ciklus starenja. Jednodnevni ciklus sastojao se od: 16h starenja pri temperaturi od 70 °C, 4 h pri temperaturi od 70 °C u prisutstvu povećane vlage i 2h u zamrzivaču na -18 °C. U svrhu praćenja procesa degradacije, određivanja toplinske stabilnosti i sadržaja adsorbirane vlage, ispitivanja mehaničkih svojstava, te analiziranja morfologije i površinskih svojstava starenih uzoraka, provedeni je karakterizacija: infracrvenom spektroskopijom (FTIR), termogravimetrijski (TGA), testom naprezanje-istezanje, pretražnim elektronskim mikroskopom (SEM) te mjerenjem kontaktnog kuta. Rezultati svih navedenih metoda su dokazali promjenu svojstava, strukture i kemijskog sastava molekula PET polimera s vremenom toplinskog starenja, ali u manjoj mjeri. Time je potvrđeno da je proces degradacije PET polimera u okolišu dugotrajan proces.

Abstract (english)

In this work, the process of atmospheric thermal aging of polymer material (the process that takes place in the environment after the disposal of plastic waste), by which microplastics are formed was simulated, and the characterization of samples has been performed after aging. For this purpose, commercial polymer materials were used: poly(ethylene terephthalate) (PET) bottles and PET foils. Aging was carried out in several time periods; 14 days, 28 days and 43 days, and each day represented one aging cycle. The one-day cycle consisted of: 16 h aging at 70 °C, 4 h at 70 °C in the presence of increased humidity and 2h in the freezer at -18 °C. To monitoring of the degradation process, determination of thermal stability, moisture adsorbtion, testing of mechanical properties, analysis of morphology and surface properties of aged samples, the characterization were performed on next methods: infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), mechanical testing machine, scanning electron microscopy (SEM) and contact angle measurements. The results of all these methods proved the change of properties, structure and chemical composition of PET polymer molecules with the time of thermal aging, but to a lower extent. The results confirmed that the process of PET polymers degradation in the environment is a long-term process.

• Keywords: atmosfersko starenje; termodegradacija; poli(etilen tereftalat); plastični otpad; mikroplastika
• Keywords (english): weathering; thermodegradation; poly(ethylene terephthalate); plastic waste; microplastics
• Language: croatian
• URN:NBN: urn:nbn:hr:149:265772
• Project: Number: IP-2020-02-6033; Title: Mikroplastika u vodi; sudbina, ponašanje i uklanjanje; Title: Microplastics in water; fate and behavior and removal; Acronym: ReMiCRO; Leader: Ana Lončarić Božić; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• 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: 2023-04-19 13:37:48