Priprava nanokompozita iz praha i taline

master's thesis

• Title (english): Nanocomposites preparation from powder and melt
• Author: Anamarija Turković
• Mentor: Mirela Leskovac (mentor)
• Committee member: Mirela Leskovac (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Vesna Ocelić Bulatović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2018-07-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Tehnologija 3D printanja zadnjih nekoliko godina privlači veliku pozornost iz razloga što se tom metodom mogu jeftino proizvesti vrlo kompleksi predmeti čija je izrada, uobičajenim tehnikama proizvodnje izrazito skupa. Jedna od tehnika 3D printanja je selektivno lasersko sinteriranje (SLS). Za ovu metodu koristi se cijeli niz polimernih materijala među kojima je i poliamid 12 (PA12) ili poznatiji pod nazivom Najlon 12. U ovom radu pripravljeni su uzorci PA12 te nanokompoziti PA12/TiO2 zamiješavanjem praha PA12 s različitim udjelom TiO2 nanopunila, φ = 0,5; 1; 1,5; i 3 % te nakon toga izravnim prešanjem na hidrauličkoj preši i zamiješavanjem PA12 s TiO2 nanopunilom u talini, na Brabender gnjetelici. Ispitivana je slobodna površinska energija komponenata metodom kontaktnog kuta i određeni su parametri adhezije nanokompozita PA12/TiO2 ovisno o načinu priprave. Toplinska svojstva uzoraka ispitana su diferencijalnom pretražnom kalorimetrijom (DSC) i termogravimetrijskom analizom (TGA), a mehanička svojstva određena su rasteznim ispitivanjem. Rezultati su pokazali da način priprave PA12/TiO2 nanokompozita nema značajan utjecaj na temperature staklastog prijelaza, kristalizacije i taljenja. Utjecaj načina priprave vidljiv je u entalpijama kristalizacije i taljenja. Za PA12/TiO2 nanokompozite koji su pripremani prešanjem iz praha entalpija kristalizacije (∆Hc) i taljenja (∆Hm) je viša u odnosu na PA12 matricu, što znači da punilo kod ovog načina priprave pokazuje nukleacijski efekt. Iz TGA rezultata može se zaključiti da način priprave nanokompozita kao i dodatak TiO2 punila nemaju utjecaja na toplinsku stabilnost PA12 matrice. Kod mehaničkih svojstava također nije zabilježen značajan utjecaj načina priprave nanokompozita.

Abstract (english)

The 3D printing technology has attracted a lot of attention over the last few years. One of the most important benefits (advantages) of 3D printing is that with this method very complex items could be produced relatively cheap in comparison with standard methods. One of methods of 3D printing is selective laser sintering (SLS). In SLS technique a whole spectrum of polymers materials can be used among which is polyamide 12 (PA12) or widely known as Nylon 12. In this paper samples of PA12 and nanocomposites PA12/TiO2 were prepared by mixing of PA12 powder with different amount, φ = 0,5; 1; 1,5; i 3 % of TiO2 nanofiller and further on direct pressing on hydraulic press and with mixing PA12 with TiO2 nanofiller in melt in Brabender plasticorder. The free surface energy of the components was studied by the contact angle measurement and adhesion parameters of PA12/TiO2 nanocomposites depending upon preparation method were determined. Thermal properties of sample were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The mechanical properties were determined by a tensile test. Results showed that preparation method of PA12/TiO2 nanocomposites has no significant effect on glass transition temperature, crystallization and melting. Influence of the nanocomposite preparation method is visible in crystallization (∆Hc) and melting (∆Hm) enthalpies. PA12/TiO2 nanocomposites prepared with direct pressing of PA12 powder and TiO2 nanofiller increased ∆Hc and ∆Hm which indicates that TiO2 nanofiller has nucleating effect on PA12 matrix. Thermal analysis showed that method of preparation and addition of TiO2 filler has no influence on thermal properties of PA12 matrix. Mechanical properties have not been significantly influenced by the preparation method of the PA12/TiO2 nanocomposites.

• Keywords: poliamid 12 (PA12); TiO2; nanokompozit; selektivno lasersko sinteriranje (SLS)
• Keywords (english): polyamide 12 (PA12); TiO2; nanocomposite; selective laser sintering (SLS)
• Language: croatian
• URN:NBN: urn:nbn:hr:149:604352
• 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: Open access
• Created on: 2020-07-21 09:02:13