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
Hemicellulose as barrier material
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
2006 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

Polysaccharides constitute an important source of raw materials for the packaging industry today. Polysaccharides have good natural barrier properties which are necessary for packaging films. Cellulose is the forerunner among renewable polymers for such applications. Hemicelluloses represent a new interesting breed of barrier materials. We have chosen to work with the hemicellulose O-acetyl-galactoglucomannan (AcGGM). The high water solubility of this particular hemicellulose extracted from process waters is both an advantage and a limiting factor. However, through the right modification, the water sensitivity of AcGGM can be regulated.

This thesis presents four ways to modify AcGGM: (i) benzylation, (ii) plasma surface treatment followed by styrene addition, (iii) vapor-phase (VP) surface grafting with styrene, and (iv) lamination of an unmodified film with a benzylated material. The most important methods of analysis of the films produced include contact angle measurement, dynamic mechanical analysis under moisture scan, and oxygen gas permeability measurement.

It was found that unmodified AcGGM films have low oxygen permeability at intermediate relative humidity (50 % RH) and good dynamic mechanical properties over a wider humidity range. Films of benzylated material (BnGGM) exhibited a decrease in oxygen permeability at lower humidity but showed better tolerance to higher humidities and indicated better dynamic mechanical behavior than AcGGM films. Lamination proved to be the most promising technique of modification, combining the good gas barrier properties of AcGGM films with the moisture-insensitivity of the BnGGM films.

Place, publisher, year, edition, pages
Stockholm: KTH , 2006. , 61 p.
Series
Trita-FPT-Report, ISSN 1652-2443 ; 2006:7
Keyword [en]
Hemicellulose, galactoglucomannan, plasma surface treatment, vaporphase grafting, benzylation, contact angle, oxygen permeability, solution casting
National Category
Paper, Pulp and Fiber Technology
Identifiers
URN: urn:nbn:se:kth:diva-3907ISBN: 91-7178-293-1 (print)OAI: oai:DiVA.org:kth-3907DiVA: diva2:9975
Presentation
2006-04-07, Sal E2, KTH, Lindstedtsvägen 3, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20101117Available from: 2006-04-06 Created: 2006-04-06 Last updated: 2010-11-17Bibliographically approved
List of papers
1. Oxygen barrier materials from renewable sources: materials properties of softwood hemicellulose-based films
Open this publication in new window or tab >>Oxygen barrier materials from renewable sources: materials properties of softwood hemicellulose-based films
2006 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 100, no 4, 2985-2991 p.Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to investigate the film-forming ability of the hemicellulose O-acetyl-galactoglucomannan (AcGGM) and to evaluate its potential as a barrier material. The polymer film was evaluated by measurement of its oxygen permeability (Ox-Tran® Mocon), thermal properties (differential scanning calorimetry), and dynamic mechanical properties under a humidity scan (humidity-scan DMA). The AcGGM was isolated from industrial process water obtained from mechanical wood pulping. The self-supporting films were formed by solution-casting from water. As expected, a plasticizer was needed to avoid brittleness, and glycerol, sorbitol, and xylitol were compared. However, these additives resulted in higher sensitivity to moisture, which might be less beneficial for some applications. Interesting oxygen barrier and mechanical strength properties were achieved in a film obtained from a physical blend of AcGGM and either alginate or carboxymethylcellulose, both having a substantially higher molecular weight than AcGGM. No phase separation was observed, since all the components used were rich in hydroxyl functionalities. When a plasticizer was also added to the binary mixture, a compromise between (1) low O2 permeability, (2) high mechanical toughness, and (3) flexibility of an AcGGM-based film was obtained.

Keyword
Galactoglucomannan, Hemicellulose, Mechanical properties, Oxygen permeability, Solution casting
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-5567 (URN)10.1002/app.22958 (DOI)000236423600053 ()2-s2.0-33645776982 (Scopus ID)
Note
QC 20100927. Uppdaterad från In press till Published (20100927).Available from: 2006-04-06 Created: 2006-04-06 Last updated: 2017-11-21Bibliographically approved
2. Surface- and bulk-modified galactoglucomannan hemicellulose films and film laminates for versatile oxygen barriers
Open this publication in new window or tab >>Surface- and bulk-modified galactoglucomannan hemicellulose films and film laminates for versatile oxygen barriers
2006 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 7, no 6, 1983-1989 p.Article in journal (Refereed) Published
Abstract [en]

The objective of this study was to create oxygen barrier films based on the hemicellulose O-acetylgalactoglucomannan (AcGGM) that show high resistance toward moisture-rich conditions. We have applied Williamson benzylation, a classic derivatization method of carbohydrates, as well as two different methods for surface grafting, and, finally, lamination of unmodified hemicellulose films with the synthesized hydrophobic benzylgalactoglucomannan (BnGGM). It was found that the thermoplastically behaving BnGGM could form independent transparent and strong films that were easy to handle. As expected, their resistance toward water was very high, and the oxygen barrier properties showed drastically lower sensitivity toward moisture than films from the corresponding unmodified material. The surface grafting and lamination methods were approached in order to try and combine excellent barrier properties with moisture tolerance. It was found that the grafting methods applied had a positive effect in this direction; however, lamination turned out to be an even more promising option.

Keyword
KONJAC GLUCOMANNAN, WOOD, XYLAN
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-5568 (URN)10.1021/bm060129m (DOI)000238180600040 ()2-s2.0-33745617914 (Scopus ID)
Note
QC 20100930. Uppdaterad från Submitted till Published (20100930).Available from: 2006-04-06 Created: 2006-04-06 Last updated: 2017-11-21Bibliographically approved
3. Hydrogels from polysaccharides for biomedical applications
Open this publication in new window or tab >>Hydrogels from polysaccharides for biomedical applications
2007 (English)In: Materials, Chemicals, and Energy from Forest Biomass / [ed] Dimitris S. Argyropoulos, 2007, 153-167 p.Chapter in book (Other academic)
Abstract [en]

Development of products made from renewable sources is considered to be a strategic research area by the international scientific community since it is generally accepted that the fossil fuels will be exhausted in the foreseeable future. Another related strategic area is the development of new bioactive and biocompatible polymers capable of exerting a temporary therapeutic function. Among other substances, polysaccharides have been proposed to be suitable materials as matrixes for the preparation of hydrogels, e.g., for use in key applications such as drug release systems and tissue engineering. Methods reported for preparation of hydrogels using renewable polysaccharides aimed for biomedical use will be reviewed.

Series
ACS Symposium Series, ISSN 0097-6156 ; 954
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-5569 (URN)10.1021/bk-2007-0954.ch010 (DOI)2-s2.0-36749034869 (Scopus ID)978-084123981-4 (ISBN)
Note
QC 20101117Available from: 2006-04-06 Created: 2006-04-06 Last updated: 2010-11-17Bibliographically approved

Open Access in DiVA

fulltext(775 kB)4648 downloads
File information
File name FULLTEXT01.pdfFile size 775 kBChecksum MD5
6a3a6f949397eb14be7306276d82caabb55cdef71c3b043a304f5fc9ba4db7fc3ab597ae
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Jonas, Hartman
By organisation
Fibre and Polymer Technology
Paper, Pulp and Fiber Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 4648 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: 1366 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