Topochemical acetylation of cellulose nanopaper structures for biocomposites: mechanisms for reduced water vapour sorption
2014 (English)In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 21, no 4, 2773-2787 p.Article in journal (Refereed) Published
Moisture sorption decreases dimensional stability and mechanical properties of polymer matrix biocomposites based on plant fibers. Cellulose nanofiber reinforcement may offer advantages in this respect. Here, wood-based nanofibrillated cellulose (NFC) and bacterial cellulose (BC) nanopaper structures, with different specific surface area (SSA), ranging from 0.03 to 173.3 m(2)/g, were topochemically acetylated and characterized by ATR-FTIR, XRD, solid-state CP/MAS C-13-NMR and moisture sorption studies. Polymer matrix nanocomposites based on NFC were also prepared as demonstrators. The surface degree of substitution (surface-DS) of the acetylated cellulose nanofibers is a key parameter, which increased with increasing SSA. Successful topochemical acetylation was confirmed and significantly reduced the moisture sorption in nanopaper structures, especially at RH = 53 %. BC nanopaper sorbed less moisture than the NFC counterpart, and mechanisms are discussed. Topochemical NFC nanopaper acetylation can be used to prepare moisture-stable nanocellulose biocomposites.
Place, publisher, year, edition, pages
2014. Vol. 21, no 4, 2773-2787 p.
Cellulose nanofibers, Bacterial cellulose, Nanopaper, Topochemical acetylation, Moisture sorption, Nanocomposites
IdentifiersURN: urn:nbn:se:kth:diva-153274DOI: 10.1007/s10570-014-0334-zISI: 000341490200049ScopusID: 2-s2.0-84904310610OAI: oai:DiVA.org:kth-153274DiVA: diva2:752955
QC 201410062014-10-062014-10-032015-05-26Bibliographically approved