Isocyanate-rich cellulose nanocrystals and their selective insertion in elastomeric polyurethane
2011 (English)In: Composites Science And Technology, ISSN 0266-3538, Vol. 71, no 16, 1953-1960 p.Article in journal (Refereed) Published
Cellulose nanocrystals (CNC) were successfully obtained and modified with 1,6-hexamethylene diisocyanate (HE)!) by means of in situ polymerization varying the CNC/HDI molar ratio to evaluate the number of anchored chains to the CNC. The modification was examined by elemental analysis, nuclear magnetic resonance ((13)C NMR) and attenuated total reflection Fourier transform infrared spectroscopy (IR-ATR). Nanocomposites containing 1.5 wt% CNC, modified and unmodified, were prepared by solvent casting. Thermal and mechanical properties of the resulting films were evaluated from the viewpoint of polyurethane microphase separated structure, soft and hard domains. CNC were effectively dispersed in the polyurethane matrix and depending on surface chemistry, the nanoreinforcement interacts selectively with matrix nanodomains. This interpretation is supported by differences in thermal and mechanical properties of the nanocomposites and also confirmed by AFM images. Isocyanate rich cellulose nanocrystals interacted with matrix hard phase, promoting physical association with hard segments, enhancing stiffness and dimensional stability versus temperature of the nanocomposite.
Place, publisher, year, edition, pages
2011. Vol. 71, no 16, 1953-1960 p.
Nanocomposites, Cellulose nanocrystals, Thermomechanical properties, Atomic force microscopy (AFM), Casting
IdentifiersURN: urn:nbn:se:kth:diva-51275DOI: 10.1016/j.compscitech.2011.09.014ISI: 000297184000022ScopusID: 2-s2.0-80055023666OAI: oai:DiVA.org:kth-51275DiVA: diva2:464040
QC 201112122011-12-122011-12-122011-12-12Bibliographically approved