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South African Journal of Science

On-line version ISSN 1996-7489
Print version ISSN 0038-2353

S. Afr. j. sci. vol.103 n.1-2 Pretoria Jan./Feb. 2007

 

RESEARCH IN ACTION

 

Atomic force microscopy to determine the surface roughness and surface polarity of cell types of hardwoods commonly used for pulping

 

 

M. Meincken

Department of Forest and Wood Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa. E-mail: mmein@sun.ac.za

 

 


ABSTRACT

Atomic force microscopy can be used to determine the surface roughness and surface polarity of different cell types originating from hardwood species. This analytical method allows images representing the topography and polarity of a surface to be captured simultaneously at a molecular (nanometre) resolution. The distribution of hydrophilic (polar) groups on these cell surfaces influences the subsequent processing of woodpulp in paper manufacture. These surface properties of fibres, vessel elements and parenchyma cells were investigated for Acacia mearnsii, Eucalyptus grandis, E. dunnii and E. macarthurii. A clear distinction was observed between the cell types and the species in terms of polarity and surface roughness. All four species are currently being used for paper manufacture in South Africa,butnot with equal success. This study may help to explain the differences in pulp quality obtained for the various species.


 

 

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