Polyelectrolyte Multilayers for Fibre Engineering - The Nanoscience and Technology of Renewable Biomaterials - page 145

PEM-covered surfaces under wet conditions. A section has also been included which
examines the relation between the properties of the formed multilayers in model experi-
ments, the adhesion between wet PEMs studied using the AFM colloidal probe technique
and the properties of dry fibre/fibre joints, as well as the dry properties of papers pre-
pared from PEM-treated fibres. This shows that the PEM technology is a new and
versatile methodology for fibre engineering and that detailed information about the
properties of the PEM is essential in order to optimize the use of PEM for different
end purposes. Since the technique is based on treatment in aqueous solutions at neu-
tral pH, it is also a very gentle technique where the properties of the fibres will be
maintained.
It should be stressed, however, that the work described here has so far been focused
mainly on the formation of the layers and joints between PEM-covered surfaces. Less
work has been devoted to the characterisation of the dry properties of PEM layers on
cellulose surfaces, apart from the determination of their electrical conducting properties
(30, 36). This is naturally a very important task, since it is simple to imagine that the
properties of dry PEM films will be very important for the preparation of strong, weak,
ductile etc. adhesive joints between fibre surfaces. It is therefore anticipated that a lot of
future work will be devoted to the dry characterisation of PEMs formed with different
components and under different conditions. This work is indeed currently in progress in
the laboratory of the authors.

Acknowledgements

Rikard Lingstr om thanks the Biofibre materials research centre (BiMaC) at KTH for
financial support; Erik Johansson and Lars Wagberg thank the Biomime research centre
at KTH and Lyckeby Research Foundation for financial support.

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