Optimizacija pripreme i karakterizacija poroznog PLA

undergraduate thesis

• Title (english): Preparation optimization and characterization of porous PLA
• Author: Viktor Artuković
• Mentor: Elvira Vidović (mentor)
• Mentor: Anđela Pustak (komentor)
• Committee member: Elvira Vidović (predsjednik povjerenstva)
• Committee member: Jozefina Katić (član povjerenstva)
• Committee member: Anđela Pustak (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-07-11, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Poli(laktidna kiselina) ili polilaktid (PLA) je polimerni materijal koji je moguće pripremiti iz obnovljivih izvora poput kukuruznog škroba ili šećerne trske zbog čega se sve više primjenjuje kao prikladna zamjena konvencionalnoj plastici na petrokemijskoj osnovi. Najčešća primjena PLA je u medicinske i farmaceutske svrhe te u industriji ambalaže, no brojna istraživanja pokušavaju proširiti njegovu moguću primjenu u drugim industrijskim granama poput automobilske, poljoprivredne, industrije... More električnih sklopova te industrije pročišćavanja otpadnih voda. PLA se često obrađuje i oblikuje na različite načine kao što su 3D ispis, elektroispredanje, ekspandiranje, fazna separacija i druge kako bi se izradio PLA određenog profila za navedene primjene. Jedan od često zahtijevanih profila PLA za primjene u industriji pročišćavanja otpadnih voda jest izrada poroznog materijala, što je bila ishodišna točka istraživanja ovog rada. Priprema poroznog materijala iz komercijalnog PLA granulata provedena je procesom fazne separacije pomoću dva sustava otapalo/neotapalo: i) kloroform/smjesa n-butanola i etanola i ii) diklormetan/smjesa n-butanola i butil acetata. Prilikom izrade poroznog materijala faznom separacijom mijenjali su se način i uvjeti sušenja, miješanja te količine dodanog neotapala. Praćenje porozne strukture materijala provedeno je pomoću pretražnog elektronskog mikroskopa (SEM), a ispitivala su se i mehanička svojstva uzoraka. Određivale su se vrijednosti toplinske vodljivosti, električne otpornosti te kontaktnog kuta. Primjenjivale su se i diferencijalna pretražna kalorimetrija te dinamičko-mehanička analiza. Rezultati pokazuju da je sustav otapalo/neotapalo i dodatak neotapala utjecao na poroznu strukturu materijala. Mehaničko ispitivanje pokazalo je da se sušenjem u običnom sušioniku dobivaju čvršći PLA filmovi, dok se sušenjem u vakuum sušioniku dobivaju žilavi filmovi. Uzorci sustava kloroform/smjesa n-butanola i etanola pokazali su manje vrijednosti toplinske vodljivosti dok su uzorci sustava diklormetan/smjesa n-butanola i butil acetata pokazali hidrofobno ponašanje. Less

Abstract (english)

Poly(lactic acid) or polylactide (PLA) is a polymer material that can be prepared from renewable sources such as corn starch or sugar cane, which is why it is increasingly used as a suitable replacement for conventional petrochemical-based plastics. The most common application of PLA is for medical and pharmaceutical purposes and in the packaging industry. Still, numerous researchers are trying to expand its application to other industry branches such as automotive, agricultural,... More electrical, and wastewater treatment. With this, PLA is often processed in various ways, such as 3D printing, electrospinning, foaming, phase separation and others, to produce a specific profile for the specified applications. One of the frequently requested profiles of PLA for use in wastewater treatment is the production of porous carrier material, which was the starting point of this work. Preparation of porous material from commercial PLA pellets was carried out by phase separation using two solvent/non-solvent systems: i) chloroform/mixture of n-butanol and ethanol and ii) dichloromethane/mixture of
n-butanol and butyl acetate. During the preparation of porous material by phase separation, the method and conditions of drying, mixing and the amount of non-solvent added were changed. The porous structure of the material was monitored by scanning electron microscopy (SEM). Mechanical properties of materials were tested and differential scanning calorimetry and dynamic-mechanical analysis were carried out. Also, thermal conductivity, contact angle and electrical resistance of materials were measured. The results show that the solvent/non-solvent system and the addition of non-solvent strongly affect the porous structure of the material. Mechanical testing showed that drying in an oven produces stronger PLA films, while drying in a vacuum oven produces tougher films. The samples of the system chloroform/mixture of n-butanol and ethanol showed lower thermal conductivity values, while the samples of the system dichloromethane/mixture of n-butanol and butyl acetate showed hydrophobic behaviour. Less

• Keywords: poli(laktidna kiselina); fazna separacija; porozni materijal.
• Keywords (english): poly(lactic acid); phase separation; porous material
• Language: croatian
• URN:NBN: urn:nbn:hr:149:213729
• Study programme: Title: Chemical Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-07-19 13:01:57