Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Synthesis of Thermo Expandable Microspheres
KTH, School of Chemical Science and Engineering (CHE).
2011 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesisAlternative title
Syntes av termiskt expanderbara mikrosfärer (Swedish)
Abstract [sv]

Termiskt expanderbara mikrosfärer är ihåliga polymera partiklar i vilka en flyktig drivgas har kapslats in. När mikrosfärerna upphettas förgasas drivgasen, vilket ökar trycket i mikrosfärerna så att de expanderar och deras volym ökar avsevärt. Denna unika egenskap gör att expanderade mikrosfärer har en låg densitet och är lämpliga för applikationer där låg vikt är väsentligt, och för att förändra ytstrukturer, så som i till exempel konstläder och textiler.

Syftet med denna studie har varit att utveckla ett stabilt system för suspensionspolymerisation för att ge en liten mikrosfär (~20 μm efter expansion) som expanderar vid relativt höga temperaturer. Detta har uppnåtts genom att undersöka effekterna av förändringar i stabiliseringssystemet. Komponenterna som varierades var mängden silika (LX), kondensationsoligomeren mellan adipinsyra och dietanolamin (KO), olika formuleringar och mängd av dilauryl peroxid, samt mängden m(III)nitrat. Ytterligare tester gjordes runt effekten av tvärbindning, tillsats av monomeren metyl metakrylat (MMA), samt tillsats av salt (NaCl).

Ett stabilt system för polymerisation i 1L-skala med en homogen dispersion uppnåddes med en av dilauryl peroxide formuleringarna tillsammans med en större mängde LX och KO. Studien visar även att kvoten mellan LX och KO har en signifikant effekt på systemets stabilitet och att mängden av både LX och KO påverkar partikelstorleken.

Abstract [en]

Thermally expandable microspheres are hollow polymeric particles in which a blowing agent has been encapsulated. Upon heating the blowing agent will vaporize, causing the internal pressure to increase, thereby expanding the microspheres. This unique expandable property reduces the density of the microspheres tremendously and makes them excellent for many applications, as for example as light weight fillers and to alter surface textures, such as in artificial leather and textiles.

The purpose of this study has been to develop a viable system for the suspension polymerization of a small microsphere (~20 μm when expanded) expanding at fairly high temperatures. This has been accomplished by investigating the effect of changes in the stabilization system. Components of the stabilization system that have been varied were the amounts of silica (LX), condensation oligomer from adipic acid and diethanol amine (KO), and m(III)nitrate, as well as different formulations and amounts of the initiator dilauryl peroxide. Additional tests were performed concerning the effect of the crosslinking, adding the monomer methyl methacrylate (MMA), and the addition of salt (NaCl).

A system for polymerization in 1L-scale was accomplished where it was found that one of the dilauryl peroxide formulations together with a higher amount of LX and KO provided a stable system giving homogeneous dispersions in which the microspheres have the desired expansion properties. Also, the ratio between LX and KO had a significant effect on the stability of the system and the amount of both LX and KO affects the particle size.

Place, publisher, year, edition, pages
2011. , 37 p.
Keyword [en]
microspheres; expandable, filler; suspension polymerization
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-90847OAI: oai:DiVA.org:kth-90847DiVA: diva2:506877
Educational program
Master of Science in Engineering - Chemical Science and Engineering
Uppsok
Physics, Chemistry, Mathematics
Supervisors
Examiners
Available from: 2012-03-01 Created: 2012-03-01 Last updated: 2012-03-01Bibliographically approved

Open Access in DiVA

fulltext(2441 kB)1002 downloads
File information
File name FULLTEXT01.pdfFile size 2441 kBChecksum SHA-512
820ac61dde1605562bdc6358155dfe3394f3233d6fdb143e45a85d2de43a10dd58d46e85260d65e489690a348ca3e4da4cd8221ffb281e9a18517b417a3fa4f8
Type fulltextMimetype application/pdf

By organisation
School of Chemical Science and Engineering (CHE)
Polymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 1002 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 456 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf