Micromorphological studies of modified wood using a surface preparation technique based on ultraviolet laser ablation

Abstract The objective of this paper is to demonstrate an ultraviolet (UV) laser ablation technique as a tool for sample preparation in microscopy studies of modified wood. Improved techniques for studying the microstructure of modified wood are crucial for a deeper understanding of many of their physical, mechanical and durability properties. The surface preparation technique is described in this paper. An illustration of micrographs of the micromorphology and polymer distribution in some examples of modified wood is also presented. It is clearly demonstrated that in contrast to conventional surface preparation techniques used for light microscopy and scanning electron microscopy, i.e. razor blade and microtome cutting techniques, UV laser ablation does not introduce any mechanically induced microcracks and redistribution of polymers or other mobile substances in the prepared surface. Results also show that, in particular, this technique seems to be suitable for studying polymer distribution in resin-impregnated wood, as well as detection of microcracks in modified wood cell walls.

[1]  J. Seltman.  Freilegen der Holzstruktur durch UV-Bestrahlung , 1995, Holz als Roh- und Werkstoff.

[2]  Gunnar Almkvist,et al.  The chemistry of the Vasa , 2008 .

[3]  M. Wålinder,et al.  Micromorphology, moisture sorption and mechanical properties of a biocomposite based on acetylated wood particles and cellulose ester , 2007 .

[4]  M. Schneider.  Wood Polymer Composites , 2007 .

[5]  W. Viöl,et al.  UV laser ablation and plasma treatment of wooden surfaces – a comparing investigation , 2006 .

[6]  D. Sandberg,et al.  Crack formation due to weathering of radial and tangential sections of pine and spruce , 2006 .

[7]  C. Hill,et al.  Wood Modification: Chemical, Thermal and Other Processes , 2006 .

[8]  A. O. Rapp,et al.  European Thematic Network for Wood Modification REVIEW ON HEAT TREATMENTS OF WOOD , 2006 .

[9]  Roger M. Rowell,et al.  Handbook of wood chemistry and wood composites. , 2005 .

[10]  Y. Ishimaru,et al.  Transverse swelling behavior of hinoki (Chamaecyparis obtusa) revealed by the replica method , 2001, Journal of Wood Science.

[11]  Mats Westin,et al.  Properties of furfurylated wood , 2004 .

[12]  R. Wu,et al.  Microstructural study of sanded and polished wood by replication , 1998, Wood Science and Technology.

[13]  R. Wu,et al.  Microstructural investigation of UV-laser irradiated pine (Pinus silvestris L.) , 1998, Wood Science and Technology.

[14]  H. Militz.  Treatment of timber with water soluble dimethylol resins to improve their dimensional stability and durability , 1993, Wood Science and Technology.

[15]  H. Günther,et al.  157 nm fluorine laser ablation of wooden surfaces as an improved preparation technique for microscopy , 2004 .

[16]  Y. Mai,et al.  Mechanical properties of wood flake–polyethylene composites. Part I: effects of processing methods and matrix melt flow behaviour , 2001 .

[17]  I. Johansson,et al.  Weak boundary layers on wood surfaces , 2000 .

[18]  J. G. Phillips,et al.  Physical and Mechanical Properties of Wood Polymer Composites , 2000 .

[19]  D. Sandberg.  Weathering of Radial and Tangential Wood Surfaces of Pine and Spruce , 1999 .

[20]  M. Sugiyama,et al.  Viscoelastic properties of the matrix substance of chemically treated wood , 1998 .

[21]  I. Johansson,et al.  UV Laser Ablation — An Improved Method of Sample Preparation for Microscopy , 1998 .

[22]  P. L. Brelid.  Acetylation of Solid Wood. Wood Properties and Process Development , 1998 .

[23]  A. Tillman,et al.  A Simplified Procedure for the Acetylation of Hardwood and Softwood Flakes for Flakeboard Production , 1986 .

[24]  R. Linsker,et al.  Far‐ultraviolet laser ablation of atherosclerotic lesions , 1984, Lasers in surgery and medicine.

[25]  N. Basov,et al.  Laser Operating in the Vacuum Region of the Spectrum by Excitation of Liquid Xenon with an Electron Beam , 1970 .