Journal
INDUSTRIAL CROPS AND PRODUCTS
Volume 93, Issue -, Pages 267-275Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.indcrop.2016.02.037
Keywords
Glass transition (Tg) of cellulose; Biomimicry; LbL assembly; TEMPO cellulose
Categories
Funding
- Institute of Critical Technology and Applied Science of Virginia Tech
Ask authors/readers for more resources
Natural composites like wood are scale integrated structures from molecular to the macroscopic scale. Inspired by this design, layer-by-layer (LbL) deposition technique was used to create lignocellulosic composites from isolated wood polymers with an ordered architecture from the nano to the microscale level. The objective of this study was to investigate the effect of the LbL ordering versus a cast film composed of a blended mixture of the same polymers using dynamic mechanical analysis (DMA). The composites were made from TEMPO-oxidized nanocellulose (TONc) obtained by fibrillation of TEMPO mediated oxidized pulp fibers, organosolv lignin (OL), and a cationic polyelectrolyte poly(diallyldimethylammonium chloride) (PDDA) used as a linking layer. DMA was performed on thin films that were saturated with ethylene glycol, utilizing a parallel-plate compression-torsion geometry. In the temperature range that was studied (0-120 degrees C), a single tan 3 peak was observed in the 30-40 degrees C region for both nanocomposite films. A neat NC cast film was tested under similar conditions that displayed a similar relaxation in this region. The peak was seen to disappear in case of LbL films in the second heat, whereas it was recurring in case of cast films of the blended mixture, and neat NC films. Heating of the samples under a compressive force produced an opposite effects in the two films; the LbL films exhibited swelling, whereas the cast films showed densification Furthermore, the tan delta peak in the second heat of cast films was found to be frequency dependent, while the LbL film did not show the same behavior. The apparent activation energies calculated (65-80 kJ mol(-1)) for these film based on the Arrhenius equation was found to be coincident to those reported for the beta transition of cellulose. (C) 2016 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available