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SANS Study of Chirality and Order in Liquid Crystalline Cellulose Suspensions

Published online by Cambridge University Press:  22 February 2011

W.J. Orts ,
J.-F. Revol ,
L. Godbout  and
R.H. Marchessault
W.J. Orts
Affiliation:
NIST, Gaithersburg, MD 20899
J.-F. Revol
Affiliation:
PAPRICON, McGill Pulp and Paper Research Centre, Montreal, PQ, H3A 2A7 Canada
L. Godbout
Affiliation:
PAPRICON, McGill Pulp and Paper Research Centre, Montreal, PQ, H3A 2A7 Canada
R.H. Marchessault
Affiliation:
PAPRICON, McGill Pulp and Paper Research Centre, Montreal, PQ, H3A 2A7 Canada
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Abstract

Small angle neutron scattering, SANS, was used to describe the magnetic alignment and in situ shear ordering of polyelectrolytic, liquid crystalline cellulose microfibrils in aqueous (D2O) suspension. In a 2.4 Tesla magnetic field, microfibril suspensions exhibit anisotropic chiral nematic (cholesteric) ordering in which the distance between nematic planes along the cholesteric axis is shorter than between rods within a nematic plane. This is consistent with the hypothesis that cellulose microfibrils are helically twisted rods. During shear, the SANS interference peaks perpendicular to the flow direction sharpen with increasing shear rate. Yet, the highest degree of alignment (for microfibrils with axial ratios of ~45) was observed a short period after the cessation of shear flow.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 376: Symposium BB – Neutron Scattering in Materials Science , 1994 , 317
Copyright
Copyright © Materials Research Society 1995

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References

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