Polimerni kompoziti kao ambalažni materijali

undergraduate thesis

• Title (english): Polymer composites for packaging application
• Author: Ela Milčić
• Mentor: Emi Govorčin Bajsić (mentor)
• Committee member: Emi Govorčin Bajsić (predsjednik povjerenstva)
• Committee member: Vesna Ocelić Bulatović (član povjerenstva)
• Committee member: Mirela Leskovac (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Udio ambalažnog otpada neprestano raste i postao je jedan od najštetnijih utjecaja na okoliš. U razvijenim zemljama svijeta, onečišćenje ambalažnim materijalom od sintetskih polimera predstavlja sve veći problem. Stoga se sve veći naglasak stavlja na razvoj biorazgradljivih polimera kao i na razvoj same biorazgradnje, te na promjeni strukture i svojstava polimera koji nalaze svakodnevnu primjenu. Biorazgradljiva ambalaža proizvodi se iz obnovljivih izvora i razgrađuju se djelovanjem mikroorganizama iz prirode na vodu, ugljikov dioksid i biomasu. Kao biorazgradljivi ambalažni materijali koriste se polimeri na bazi škroba i polihidroksialkanoati te poliesteri poput polimera na bazi polilaktidne kiseline. Škrob se kao prirodni polimer nalazi u biljkama kao što su kukuruz, pšenica, riža i grašak, tako da se ističe svojom niskom cijenom i lakom dostupnošću. Fizikalna obrada prirodnog škroba, tj. lom njegove zrnate strukture dodatkom nekog plastifikatora proizvodi termoplastični škrob (TPS), kojeg je moguće prerađivati postupcima prerade polimera. Cilj ovoga rada je ispitivanje toplinskih svojstava biorazgradljivih polimera, polilaktida (PLA) i termoplastičnog škroba (TPS) pripremljenog s različitim udjelom glicerola kao plastifikatorom. Toplinska svojstva ispitivanih uzoraka analizirana su primjenom diferencijalne pretražne kalorimetrije (DSC) i termogravimetrijske analize (TGA). Obzirom na hidrofilni karakter TPS-a, te suprotno njemu hidrofoban karakter PLA, ispitana je apsorpcija vode njihovih mješavina. Rezultati ukazuju da dodatkom TPS-a u PLA dolazi do porasta stupnja kristalnosti PLA, Dodatak PLA u TPS utječe na porast toplinske stabilnost TPS-a. Utjecaj glicerola kao plastifikatora TPS-a nema značajnu ulogu u ispitivanju toplinskih svojstava, dok je ispitivanje apsorpcije vode pokazalo da se uz veći udio glicerola dobivaju niže vrijednosti apsorpcije vode.

Abstract (english)

The content of packaging waste is constantly increasing and it has became one of the most harmful impacts on the environment. In developed countries of the world packaging waste from synthetic polymers is growing problem. Biodegradable polymers are a useful option since these polymers should have no adverse impact on environmental. Biodegradable packaging material is produced from renewable sources and degradated by the action of microorganisms from nature to water, carbon dioxide and biomass. As biodegradable packaging materials, starch-based polymers and polyhidroxyalkanoates and polyesters such as polylactide-based are used. Starch as a natural polymer is found in plants such as corn, wheat, rice and peas, so it stands out with it´s low price and availability. Physical treatment of natural starch, that is, the fracture of its grainy structure by the addition of a plasticizer produces thermoplastic starch (TPS), which can be processed by polymers processing methods. The aim of this work is to investigate the thermal properties of biodegradable polymers, polylactide (PLA) and thermoplastic starch (TPS) prepared with different glycerol content as a plasticizer. The thermal properties of the samples were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Considering hydrophilic character of TPS, and opposite of him the hydrophobic character of PLA, water absorption of their blends was measured. The results indicated that the addition of TPS in PLA increases the degree of crystalinity of PLA. With the addition of PLA to TPS the thermal stability of TPSincreased. The glycerol as a plasticizer for TPS has no significant effect of on the thermal properties, while the higher glycerol content has lower water absorption values.

• Keywords: biorazgradiva ambalaža; polilaktid; termoplastični škrob
• Keywords (english): biodegradable packaging; polylactide; thermoplastic starch
• Language: croatian
• URN:NBN: urn:nbn:hr:149:007765
• Study programme: Title: Materials Science and 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: 2021-01-08 10:17:39