magistrsko delo
Noemi Sep (Avtor), Lidija Čuček (Mentor), Lidija Fras Zemljič (Komentor), Olivija Plohl (Komentor)

Povzetek

Namen magistrske naloge je bil preučiti in primerjati mehanizme degradacije oziroma fragmentacije štirih konvencionalnih plastičnih materialov (polietilen tereftalat (PET), recikliran polietilen tereftalat (rPET), vlakna polietilen tereftaltata (PETFIB), vlakna melaminske eterificirane smole (MERFIB)) in enega biorazgradljivega plastičnega materiala (polilaktična kislina (PLA)) v treh modelnih vodah z različnimi vrednostmi pH (4, 7 in 10) ter v dveh realnih vodah (pitna voda in morska voda). Fragmentacijo plastičnih materialov smo preučevali za njihovo izpostavljenost v treh različnih časovnih obdobjih (1 mesec, 3 meseci in 6 mesecev). Tako smo primerjali kinetiko degradacije/fragmentacije različnih plastičnih materialov ter preučevali vpliv različnih parametrov, kot sta časovna izpostavljenost, vpliv naravnega okolja ter pH vrednosti na kinetiko degradacije. V sklopu magistrske naloge smo prav tako izvedli eksperiment, pri čemer smo uporabili 10-kratno količino začetnega vzorca, kjer smo spremenili razmerje med materialom in vodnim medijem. Na koncu smo izvedli še standardni test za določanje toksičnost (TCLP) po standardu SW-846 Test Method 1311. Spremembe v masi plastičnih materialov ter količino nastale mikroplastike smo kvantificirali s pomočjo gravimetrije. Morebitne morfološke spremembe materiala smo okarakterizirali s pomočjo optičnega mikroskopa, morebitne spremembe funkcionalnih skupin pa smo spremljali z ATR-FTIR spektroskopijo. V vodnih medijih smo spremljali spreminjanje naslednjih parametrov: pH vrednost, prevodnost, motnost, povprečno velikost delcev ter skupni organski ogljik. Med petimi preučevanimi materiali kaže MERFIB največjo stopnjo degradacije, najbolj obstojen med preučevanimi materiali pa je konvencionalni material PET. Po šestih mesecih izpostavljenosti smo pri materialih PET, rPET in MERFIB lahko zasledili največjo stopnjo degradacije v primeru uporabe modelne vode s pH vrednostjo 4. V primeru materiala PETFIB pa se je za najučinkovitejše degradacijsko sredstvo izkazala morska voda. PLA se je najbolj degradirala v modelni vodi s pH vrednostjo 10. S pomočjo standardnega testa za določanje toksičnosti smo prav tako potrdili, da je med petimi preučevanimi materiali MERFIB najbolj nagnjen k fragmentaciji zaradi njegove vlaknaste strukture.

Ključne besede

plastični materiali;fragmentacija;polietilen tereftalat;recikliran polietilen tereftalat;vlakna polietilen tereftaltata;polilaktična kislina;vlakna melaminske eterificirane smole;magistrske naloge;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.09 - Magistrsko delo
Organizacija: UM FKKT - Fakulteta za kemijo in kemijsko tehnologijo
Založnik: [N. Sep]
UDK: 678.762.2.01:628.19(043.2)
COBISS: 147492355 Povezava se bo odprla v novem oknu
Št. ogledov: 73
Št. prenosov: 13
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: Fragmentation of plastic materials in different aquatic environments
Sekundarni povzetek: The purpose of the thesis was to study and compare the mechanisms of degradation or fragmentation of four conventional plastic materials (polyethylene terephthalate (PET), recycled polyethylene terephthalate (rPET), polyethylene terephthalate fibers (PETFIB), melamine etherified resin fibers (MERFIB)) and one biodegradable plastic material (polylactic acid (PLA)) in three model waters with different pH values (4, 7 and 10), and in two real waters (tap water and sea water). The fragmentation of plastic materials was studied over three different time periods (1 month, 3 months and 6 months). Thus, the kinetics of degradation/fragmentation of different plastic materials was compared and the influence of various parameters was studied on the kinetics of degradation, such as the time of exposure, the influence of the natural environment and pH value. As a part of the thesis, an experiment was also carried out, where 10 times higher amount was used compared to the initial sample, and the ratio between the material and the water medium was changed. At the end, the standard toxicity characteristic leaching procedure (TCLP) was performed according to the standard SW-846 Test Method 1311. Mass loss of materials and the amount of produced microplastics were quantified using gravimetry. Possible morphological changes of the materials were characterized using an optical microscope, and possible changes of functional groups were monitored using ATR-FTIR spectroscopy. In water samples, changes in the following parameters were monitored: pH value, conductivity, turbidity, average particle size and total organic carbon. Among the five materials studied, MERFIB shows the highest degradation rate, and virgin PET is the most durable among the materials studied. After six months of exposure, in the case of PET, rPET and MERFIB, the highest degree of degradation was observed in the case of model water with a pH value of 4. In the case of PETFIB, sea water proved to be the most effective degradation agent. PLA degraded the most in model water with a pH value of 10. With the standard toxicity characteristic leaching procedure, it was also confirmed that of the five materials studied, MERFIB is the most prone to fragmentation due to its fibrous structure.
Sekundarne ključne besede: plastic materials;fragmentation;polyethylene terephthalate;recycled polyethylene terephthalate;polyethylene terephthalate fibers;polylactic acid;melamine etherified resin fibers;
Vrsta dela (COBISS): Magistrsko delo/naloga
Komentar na gradivo: Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Strani: 1 spletni vir (1 datoteka PDF (XIV, 93 f.))
ID: 17933425