Improved barrier films of cross-linked cellulose nanofibrils: a microscopy study
2014 (English)In: Green materials, ISSN 2049-1220, Vol. 2, no 4, 163-168 p.Article in journal (Refereed) Published
It is highly desirable to replace gas barriers of aluminium and non-renewable plastics in order to lower our ecological footprint. One interesting candidate is films made from cellulose nanofibrils (CNFs), which after cross-linking have been shown to have competitive barrier properties even at a high relative humidity (80% RH). This work presents studies at even higher relative humidity (90% RH) and microscopic studies of what happens when unmodified and cross-linked CNF films are exposed to water. The microscopy techniques used were scanning electron microscopy of dry and wet cross-sections of films after freeze-drying and atomic force microscopy in the dry state and in the wet state shortly after wetting. Both techniques clearly revealed that the cross-links prevent the CNFs from separating from each other and hence prevent the films from swelling, so that the free-volume-sensitive gas permeability is maintained at a low level.
Place, publisher, year, edition, pages
2014. Vol. 2, no 4, 163-168 p.
Paper, Pulp and Fiber Technology
IdentifiersURN: urn:nbn:se:kth:diva-168001DOI: 10.1680/gmat.14.00018OAI: oai:DiVA.org:kth-168001DiVA: diva2:813806
QC 201506152015-05-252015-05-252015-06-15Bibliographically approved