Utjecaj ugljikovih nanocjevčica na toplinsku vodljivost polimera

undergraduate thesis

• Title (english): Influence of carbon nanotubes on thermal conductivity of polymers
• Author: Ruth Eva Jensch
• Mentor: Sanja Lučić Blagojević (mentor)
• Committee member: Sanja Lučić Blagojević (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Elvira Vidović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2018-09-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Nove mogućnosti za zamjenu metalnih dijelova u raznim primjenama (primjerice generatorima, električnim motorima i izmjenjivačima topline) omogućuje primjena toplinski vodljivih polimernih kompozita. Nanotehnologija je potencijalna tehnologija koja bi omogućila razvoj polimernih materijala s takvim svojstvima. Naime, smatra se da bi se poboljšanje u toplinskoj vodljivosti polimera ostvarilo dodatkom izrazito vodljivih nanopunila u polimernu matricu. Najčešće korišteno nanopunilo su ugljikove nanocjevčice (CNT). U ovom završnom radu istraživan je utjecaj dodatka višestijenih ugljikovih nanocjevčica (MWCNT) na toplinsku vodljvost polilaktidne kiseline (PLA), utjecaj debljine uzorka na toplinsku vodljivost sustava PLA+MWCNT, utjecaj funkcionalizacije MWCNT-a COOH i COOC12H25 skupinama na toplinsku vodljivost sustava PLA+MWCNT te utjecaj vrste polietilenske matrice na toplinsku vodljivost sustava PE+MWCNT. Ispitivanje toplinske vodljivosti provedeno je pomoću uređaja Transient Hot Bridge. Rezultati istraživanja su pokazali da debljina uzroka znatno ne utječe na toplinsku vodljivost sustava PLA+MWCNT. Rezultati toplinske vodljivosti sustava PLA+MWCNT upućuju da dodatak ugljikovih nanocjevčica od 4 % mas uzrokuje porast toplinske vodljivosti za oko 80%. Ispitivanjem toplinske vodljivosti sustava PLA+ MWCNT-COOH te PLA+MWCNT-COOC12H25 ustanovljeno je da nema znatne razlike u vodljivosti uzrokovane funkcionalizacijom MWCNT-a. Rezultati ispitivanja utjecaja vrste polietilenske matrice na toplinsku vodljivost pokazuju da PE-HD ima znatno veću toplinsku vodljivost i znatno veći porast toplinske vodljivosti dodatkom MWCNT-a u odnosu na PE-LD. Porast toplinske vodljivosti sustava s PLA matricom znatno je veći od porasta uočenog kod sustava s PE matricom.

Abstract (english)

Thermally conductive polymer composites offer new possibilities for replacing metal parts in several applications (for example generators, electric motors and heat exchangers). Nanotechnology is a potential technology that would enable the development of polymer materials with properties. It is considered that the improvement in thermal conductivity of the polymer could be accomplished by the addition of highly conductive nanofillers in the polymer matrix. The most commonly used nanofillers are carbon nanotubes (CNT). The objective of this study was to determine the effect of the addition of multi-walled carbon nanotubes (MWCNT) to the thermal conductivity of polylactide acid (PLA), the influence of the sample thickness on the thermal conductivity of the PLA + MWCNT system, the influence of the MWCNT COOH and COOC12H25 groups on the thermal conductivity of PLA + MWCNT and the influence of the polyethylene matrix on the thermal conductivity of PE + MWCNT. The heat conductivity was measured by using the Transient Hot Bridge. The research results have shown that the thickness of the sample does not significantly affect the thermal conductivity of the PLA + MWCNT system. The thermal conductivity of the PLA + MWCNT system suggests that the addition of carbon nanotubes in 4% mass causes an increase in thermal conductivity by approximately 80%. Measuring the thermal conductivity of PLA + MWCNT-COOH and PLA + MWCNT-COOC12H25 showed that there was no significant difference in thermal conductivity caused by the functionalization of MWCNT. The results of the polyethylene matrix influence on thermal conductivity show that PE-HD has a significantly higher thermal conductivity and a significantly higher increase in thermal conductivity by adding MWCNT than PE-LD. The increase in thermal conductivity of the system with the PLA matrix is considerably higher than the observed increase in the PE matrix system.

• Keywords: toplinska vodljivost nanokompozita; polilaktid; polietilen; višestijene ugljikove nanocjevčice (MWCNT)
• Keywords (english): thermal conductivity of nanocomposites; polylactide; polyethylene; multi-walled carbon nanotubes (MWCNT)
• Language: croatian
• URN:NBN: urn:nbn:hr:149:046876
• 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: 2021-11-22 12:41:04