Praćenje migracija aditiva iz višestruko reciklirane polietilenske mikroplastike

master's thesis

• Title (english): Monitoring the migration of additives from multiple recycled polyethylene microplastics
• Author: Dora Katarina Kovač
• Mentor: Zvonimir Katančić (mentor)
• Committee member: Zvonimir Katančić (predsjednik povjerenstva)
• Committee member: Josipa Papac Zjačić (član povjerenstva)
• Committee member: Martina Miloloža (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2025-02-21, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Polimerni materijali nalaze se svuda oko nas i koriste se u raznim proizvodima prehrambene, kozmetičke, građevinske i drugih industrija, pri čemu je polietilen jedan od najčešće korištenih polimera. Dodavanjem aditiva poboljšavaju se određena svojstva polimera koja im omogućuju primjenu u različitim industrijama. S porastom globalne proizvodnje i uporabe polimernih materijala povećava se i količina plastičnog otpada. Mehaničko recikliranje često se smatra efikasnim rješenjem za njegovo smanjenje. Iako u literaturi postoji puno istraživanja koja se temelje na proučavanju polimera i njihovih svojstava, malo se njih koncentrira na to kako višestruko recikliranje utječe na otpuštanje aditiva iz plastike. Cilj ovoga rada bio je proučavanje utjecaja višestrukog recikliranja na migraciju aditiva iz polietilenske mikroplastike. U tu svrhu pripremljena su dva uzorka. Prvi uzorak se sastojao od polietilena (PE) i antioksidansa, dok se drugi uzorak sastojao od PE-a u koji su dodani antioksidansi i plastifikator. Nakon pripreme uzoraka u laboratorijskom ekstruderu provedena je simulacija pet ciklusa mehaničkog recikliranja. Nakon svakog ciklusa uzorci su usitnjeni do veličine mikroplastike. Kako bi se ustanovile promjene u strukturi, toplinskoj stabilnosti i stupnju kristalnosti uzoraka uzrokovane aditivima, provedena je karakterizacija nakon 1., 3. i 5. ciklusa recikliranja. Metode karakterizacije uključivale su infracrvenu spektroskopiju s Fourierovom transformacijom (FTIR), termogravimetrijsku analizu (TGA) i diferencijalnu pretražnu kalorimetriju (DSC). Isto tako, praćena je i migracija aditiva iz mikroplastike u vodeni medij, prilikom čega je određen sadržaj ukupnog organskog ugljika, omjer biorazgradivosti i toksičnost na organizmima Vibrio fischeri i Daphnia magna.

Abstract (english)

Polymeric materials are all around us and are used in various products such as food, cosmetics, construction and other industries, whereby polyethylene is one of the most used polymers. The addition of additives is essential for enhancing certain properties of polymers, allowing their application in various industries. With increasing global production and usage of polymer materials, the amount of plastic waste is also increasing. Mechanical recycling is considered an effective way of solving this problem. Although there are many studies about polymers and their properties, not many of them are focused on the effect of multiple recycling cycles on the migration of additives from plastic. The aim of this thesis was to examine the effect of multiple recycling cycles on migration of additives from polyethylene microplastics. For this purpose, two samples were prepared. One of them was polyethylene (PE) with antioxidants, while the second one was PE with antioxidants and plasticizer. After preparation, a simulation of five recycling cycles was conducted in a laboratory extruder. After each cycle, the samples were ground to microplastic size. To establish changes in structure, thermal stability and degree of crystallinity of the samples, the characterization was done after 1st, 3rd and 5th cycle of recycling. These methods of characterization included Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The migration of additives from microplastic to water was also monitored, and total organic carbon (TOC), ratio of biodegradability and toxicity on organisms Vibrio fischeri and Daphnia magna were determined.

• Keywords: polietilen; aditivi; mehaničko recikliranje; mikroplastika; toksičnost
• Keywords (english): polyethylene; additives; mechanical recycling; microplastics; toxicity
• Language: croatian
• URN:NBN: urn:nbn:hr:149:775665
• 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: Hrvatska zaklada za znanost; Funding stream: Research Projects
• Study programme: Title: Environmental Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra inženjer/inženjerka ekoinženjerstva (sveučilišni/a magistar/magistra inženjer/inženjerka ekoinženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-01-01
• Created on: 2025-02-28 13:13:17