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
Polymer Nanocomposites in Thin Film Applications
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.ORCID iD: 0000-0001-7132-3251
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The introduction of a nanoscopic reinforcing phase to a polymer matrix offers great possibilities of obtaining improved properties, enabling applications outside the boundaries of traditional composites.

The majority of the work in this thesis has been devoted to polymer/clay nanocomposites in coating applications, using the hydroxyl-functional hyperbranched polyester Boltorn® as matrix and montmorillonite clay as nanofiller. Nanocomposites with a high degree of exfoliation were readily prepared using the straightforward solution-intercalation method with water as solvent. Hard and scratch-resistant coatings with preserved flexibility and transparency were obtained, and acrylate functionalization of Boltorn® rendered a UV-curable system with similar property improvements. In order to elucidate the effect of the dendritic architecture on the exfoliation process, a comparative study on the hyperbranched polyester Boltorn® and a linear analogue of this polymer was performed. X-ray diffraction and transmission electron microscopy confirmed the superior efficiency of the hyperbranched polymer in the preparation of this type of nanocomposites.

Additionally, an objective of this thesis was to investigate how cellulose nanofibers can be utilized in high performance polymer nanocomposites. A reactive cellulose “nanopaper” template was combined with a hydrophilic hyperbranched thermoset matrix, resulting in a unique nanocomposite with significantly enhanced properties. Moreover, in order to fully utilize the great potential of cellulose nanofibers as reinforcement in hydrophobic polymer matrices, the hydrophilic surface of cellulose needs to be modified in order to improve the compatibility. For this, a grafting-from approach was explored, using ring-opening polymerization of ε-caprolactone (CL) from microfibrillated cellulose (MFC), resulting in PCL-modified MFC. It was found that the hydrophobicity of the cellulose surfaces increased with longer graft lengths, and that polymer grafting rendered a smoother surface morphology. Subsequently, PCL-grafted MFC film/PCL film bilayer laminates were prepared in order to investigate the interfacial adhesion. Peel tests demonstrated a gradual increase in the interfacial adhesion with increasing graft lengths.

Place, publisher, year, edition, pages
Stockholm: KTH , 2010. , 66 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2010:12
Keyword [en]
Nanocomposites, hyperbranched polymers, montmorillonite, clay nanoparticles, exfoliated, coatings, crosslinking, TEM, XRD, mechanical properties, thermal properties, cellulose nanofibers, Atom Transfer Radical Polymerization, Ring-Opening Polymerization, poly(ε-caprolactone), surface modification, grafting, interfacial adhesion
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-12400ISBN: 978-91-7415-615-7 (print)OAI: oai:DiVA.org:kth-12400DiVA: diva2:310766
Public defence
2010-05-07, D1, Lindstedtsvägen 17, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC20100621Available from: 2010-04-20 Created: 2010-04-16 Last updated: 2012-03-28Bibliographically approved
List of papers
1. UV-curable hyperbranched nanocomposite coatings
Open this publication in new window or tab >>UV-curable hyperbranched nanocomposite coatings
2006 (English)In: Progress in organic coatings, ISSN 0300-9440, E-ISSN 1873-331X, Vol. 55, 284-290 p.Article in journal (Refereed) Published
Abstract [en]

Nanoparticles have been used to reinforce polymer matrices since the late 1980s, with promising results. Hyperbranched polymers are densely branched molecules with a globular structure, leading to lower viscosity and many end-groups, creating property-designing opportunities. Here, the two research areas, nanocomposites and hyperbranched polymers, were combined to investigate the possibility of creating a nanocomposite resin, in order to prepare a UV-curable coating system. Nanocomposites were prepared from the hyperbranched polyester Boltorn (R) H30, acrylated to 30% and 70%, and the unmodified layered silicate Na(+)montmorillonite, added both before and after the acrylation of Boltorn (R) H30. Films prepared from 30% acrylated Boltorn (R) H30 with clay added after the acrylation, having a mainly exfoliated structure according to X-ray and TEM, exhibited the largest property improvement, compared with the unfilled film. These property improvements comprised a harder surface, better scratch resistance, better adhesion to metal substrates and a small improvement in flexibility.

Keyword
LAYERED SILICATE NANOCOMPOSITES; POLYMER/MONTMORILLONITE CLAY NANOCOMPOSITES; BARRIER PROPERTIES; POLYMER; MONTMORILLONITE; HYBRID; WATER
Identifiers
urn:nbn:se:kth:diva-13479 (URN)10.1016/j.porgcoat.2005.12.003 (DOI)000236079300010 ()2-s2.0-33244468561 (Scopus ID)
Note
QC20100618Available from: 2010-06-18 Created: 2010-06-18 Last updated: 2017-12-12Bibliographically approved
2. Hard and Flexible Nanocomposite Coatings using Nanoclay‐filled Hyperbranched Polymers
Open this publication in new window or tab >>Hard and Flexible Nanocomposite Coatings using Nanoclay‐filled Hyperbranched Polymers
2010 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, Vol. 2, no 6, 1679-1684 p.Article in journal (Refereed) Published
Abstract [en]

The combination of hardness, scratch resistance, and flexibility is a highly desired feature in many coating applications. The aim of this study is to achieve this through the introduction of an unmodified nanoclay, montmorillonite (Na+MMT), in a polymer resin based on the hyperbranched polyester Bottom H30. Smooth and transparent films were prepared from both the neat and the nanoparticle-filled hyperbranched resins. X-ray diffraction (XRD) and transmission electron microscopy (TEM) corroborated a mainly exfoliated structure in the nanocomposite films, which was also supported by results from dynamic mechanical analysis (DMA). Furthermore, DMA measurements showed a 9-16 degrees C increase in Tg and a higher storage modulus above and below the T-g-both indications of a more cross-linked network, for the clay-containing film. Thermogravimetric analysis (TGA) demonstrated the influence of the nanofiller on the thermal properties of the nanocomposites, where a shift upward of the decomposition temperature in oxygen atmosphere is attributed to the improved barrier properties of the nanoparticle-filled materials. Conventional coating characterization methods demonstrated an increase in the surface hardness, scratch resistance and flexibility, with the introduction of clay, and all coatings exhibited excellent chemical resistance and adhesion.

Keyword
nanocomposites, hyperbranched polymers, montmorillonite, coatings, mechanical properties, thermal properties, barrier properties
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-13480 (URN)10.1021/am1001986 (DOI)000278963600021 ()2-s2.0-77955494744 (Scopus ID)
Note
QC20100618. Uppdaterad från Submitted till Published (20101022).Available from: 2010-06-18 Created: 2010-06-18 Last updated: 2010-10-22Bibliographically approved
3. Linear vs. Hyperbranched Polymers in the Preparation of Polymer/Clay Nanocomposites
Open this publication in new window or tab >>Linear vs. Hyperbranched Polymers in the Preparation of Polymer/Clay Nanocomposites
Show others...
(English)Manuscript (preprint) (Other academic)
Keyword
polymer composite materials, polymer chemistry, polymer materials
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-13492 (URN)
External cooperation:
Note

QC 20100621

Available from: 2010-06-21 Created: 2010-06-21 Last updated: 2016-08-25Bibliographically approved
4. Novel nanocomposite concept based on cross-linking of hyperbranched polymers in reactive cellulose nanopaper templates
Open this publication in new window or tab >>Novel nanocomposite concept based on cross-linking of hyperbranched polymers in reactive cellulose nanopaper templates
Show others...
2011 (English)In: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 71, no 1, 13-17 p.Article in journal (Refereed) Published
Abstract [en]

Cellulosic fibers offer interesting possibilities for good interfacial adhesion due to the high density of hydroxyl groups at the surface. in the present study, the potential of a new nanocomposite concept is investigated, where a porous cellulose nanofiber network is impregnated with a solution of reactive hyperbranched polyester. The polymer is chemically cross-linked to form a solid matrix. The resulting nanocomposite structure is unique. The matrix surrounds a tough nanopaper structure consisting of approximately 20 nm diameter nanofibers with an average interfiber distance of only about 6 nm. The cross-linked polymer matrix shows strongly altered characteristics when it is cross-linked in the confined space within the nanofiber network, including dramatically increased T-g, and this must be due to covalent matrix-nanofiber linkages.

Keyword
nano composites, fibre/matrix bond, interface, dynamic mechnical thermal analysis
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-13488 (URN)10.1016/j.compscitech.2010.09.006 (DOI)000285904100003 ()2-s2.0-78649715826 (Scopus ID)
Note

QC 20100621. Updated from submitted to published 20120326. Previous title: Novel Nanocomposite Concept based on Hyperbranched Polymers in Reactive Cellulose Nanopaper Templates

Available from: 2010-06-21 Created: 2010-06-21 Last updated: 2017-12-12Bibliographically approved
5. Surface grafting of microfibrillated cellulose with poly(epsilon-caprolactone) - Synthesis and characterization
Open this publication in new window or tab >>Surface grafting of microfibrillated cellulose with poly(epsilon-caprolactone) - Synthesis and characterization
Show others...
2008 (English)In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 44, no 9, 2991-2997 p.Article in journal (Refereed) Published
Abstract [en]

In cellulose nanocomposites, the surface of the nanocellulosic phase is critical with respect to nanocellulose dispersion, network formation and nanocomposite properties. Microfibrillated cellulose (MFC) has been grafted with poly(epsilon-caprolactone) (PCL), via ring-opening polymerization (ROP). This changes the surface characteristics of MFC and makes it possible to obtain a stable dispersion of MFC in a nonpolar solvent; it also improves MFC's compatibility with PCL. The thermal behavior of MFC grafted with different amount of PCL has been investigated using thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). From TGA measurements, the fraction of PCL in MFC-PCL samples was estimated to 16%, 19%, and 21%. The crystallization and melting behavior of free PCL and MFC-PCL were studied with DSC, and a significant difference was observed regarding melting points, crystallization temperature, degree of crystallinity, as well as the time required for crystallization.

Keyword
Microfibrillated cellulose, Grafting of poly(epsilon-caprolactone), Ring-opening polymerization, Thermal gravimetric analysis, Differential scanning calorimetry, Dispersion, NONISOTHERMAL CRYSTALLIZATION, NANOCOMPOSITE MATERIALS, WHISKERS, FIBERS, BEHAVIOR, POLYCAPROLACTONE, BIOPOLYMERS, SUSPENSIONS, COPOLYMERS
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-13468 (URN)10.1016/j.eurpolymj.2008.06.023 (DOI)000260274400031 ()2-s2.0-51149086166 (Scopus ID)
Note
QC20100618Available from: 2010-06-18 Created: 2010-06-18 Last updated: 2017-12-12Bibliographically approved
6. Investigation of the graft length impact on the interfacial toughness in a cellulose/poly(ε-caprolactone) bilayer laminate
Open this publication in new window or tab >>Investigation of the graft length impact on the interfacial toughness in a cellulose/poly(ε-caprolactone) bilayer laminate
Show others...
2011 (English)In: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 71, no 1, 9-12 p.Article in journal (Refereed) Published
Abstract [en]

Interfacial adhesion between immiscible cellulose–polymer interfaces is a crucial property for fibrous biocomposites. To tailor the interfacial adhesion, the grafting of polymers from cellulose films was studied using ring-opening polymerization of ε-caprolactone. The poly(ε-caprolactone) (PCL) grafted cellulose was analyzed with FTIR, AFM and via water CA measurements. The graft length was varied by the addition of a free initiator, enabling tailoring of the interfacial toughness. Films of microfibrillated cellulose were grafted with PCL and hot-pressed together with a PCL-film to form a bilayer laminate. Interfacial peeling toughness correlates very strongly with PCL degree of polymerization (DP). PCL grafts form physical entanglements in the PCL matrix and promote significant plastic deformation in the PCL bulk, thus increasing interfacial peeling energy.

Keyword
Microfibrillated cellulose grafted with polycaprolactone, Polymer-matrix composites, Laminate, Wood, Interfacial strength, Delamination
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-13493 (URN)10.1016/j.compscitech.2010.09.007 (DOI)000285904100002 ()2-s2.0-78649690669 (Scopus ID)
Note
QC 20120328. Updated from submitted to published. Previous title: "Investigation of the Grafta Cellulose/Poly(‐Length Impact on the Interfacial Toughness ina Cellolose/Poly(ε‐caprolactone) Bilayer Laminate"Available from: 2010-06-21 Created: 2010-06-21 Last updated: 2017-12-12Bibliographically approved

Open Access in DiVA

fulltext(5947 kB)2318 downloads
File information
File name FULLTEXT01.pdfFile size 5947 kBChecksum SHA-512
7b018d4ed62115272f2dc7e7c2d6a2d292076866941355c2dc0f177c0da712430645f7059ea00de737c029f565cb65c06b730808d175344dbf2ad60396adae88
Type fulltextMimetype application/pdf
spikblad(219 kB)45 downloads
File information
File name SPIKBLAD01.pdfFile size 219 kBChecksum SHA-512
66479ff9101e578774173b210a33e642a29c570cb0bd45070d79a9fadbba48ca30ebe43e3b76ec9780bd3289e09210b036532c26181bba31db6a6b887916e5e8
Type spikbladMimetype application/pdf

Authority records BETA

Fogelström, Linda

Search in DiVA

By author/editor
Fogelström, Linda
By organisation
Coating Technology
Polymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 2318 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

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 790 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