Cellulose

, Volume 20, Issue 3, pp 1329–1342

Interplay of colloidal stability of cellulose nanocrystals and their dispersibility in cellulose acetate butyrate matrix

  • Leandro S. Blachechen
  • João Paulo de Mesquita
  • Everton Luiz de Paula
  • Fabiano V. Pereira
  • Denise F. S. Petri
Original Paper

DOI: 10.1007/s10570-013-9881-y

Cite this article as:
Blachechen, L.S., de Mesquita, J.P., de Paula, E.L. et al. Cellulose (2013) 20: 1329. doi:10.1007/s10570-013-9881-y

Abstract

Cellulose nanocrystals (CNC) prepared from eucalyptus cellulose CNCs were modified by the reaction with methyl adipoyl chloride, CNCm, or with a mixture of acetic and sulfuric acid, CNCa. The CNC were either dispersed at 0.1 wt% in the pure solvents ethyl acetate (EA), tetrahydrofuran (THF) and dimethylformamide (DMF) or in cellulose acetate butyrate (CAB) solutions prepared in these solvents at 0.9 wt%. The colloidal behavior of these dispersions was systematically investigated using a phase separation analyzer LUMiReader®. The mechanical properties and morphological features of the films resulting from the mixtures of CAB and CNC were determined by dynamic mechanical analysis, optical microscopy and atomic force microscopy, respectively. Regardless the functional group attached to the surface of CNC, the best colloidal stability was observed for dispersions prepared in CAB/DMF solution. Higher degree of substitution of modified CNCs favored the colloidal stability in EA and THF. Composite films prepared from CAB/DMF solutions were more homogeneous and presented better mechanical performance than those prepared in CAB/EA or CAB/THF. The mechanical performance of composites and neat CAB prepared from DMF was CAB/CNCs > CAB/CNCm > CAB/CNCa > CAB, indicating that the modification weakens the percolation process, which is mediated by H bonding.

Keywords

Cellulose nanocrystalsCellulose acetate butyrateColloidal stabilityMechanical propertiesMorphology

Abbreviations

CAB

Cellulose acetate butyrate

CNC

Cellulose nanocrystals

CNCs

Cellulose nanocrystals functionalized with sulfate groups

CNCa

Cellulose nanocrystals functionalized with sulfate and acetate groups

CNCm

Cellulose nanocrystals functionalized with sulfate and methyl adipoyl groups

EA

Ethyl acetate

THF

Tetrahydrofuran

DMF

N,N-dimethylformamide

DMA

Dynamic mechanical analysis

OM

Optical microscopy

AFM

Atomic force microscopy

DSa

Degree of substitution of acetate

DSBu

Degree of substitution of butyrate

DSm

Degree of substitution of methyl acetate

εr

Relative permittivity

CMC

Carboxymethylcellulose

XG

Xyloglucan

BCN

Bacterial cellulose nanocrystals

E

Young’s modulus

σ

Tensile strength

Supplementary material

10570_2013_9881_MOESM1_ESM.pdf (405 kb)
Supplementary material 1 (PDF 405 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Leandro S. Blachechen
    • 1
  • João Paulo de Mesquita
    • 2
  • Everton Luiz de Paula
    • 2
  • Fabiano V. Pereira
    • 2
  • Denise F. S. Petri
    • 1
  1. 1.Instituto de QuímicaUniversidade de São PauloSão PauloBrazil
  2. 2.Departamento de QuímicaUniversidade Federal de Minas GeraisBelo HorizonteBrazil