X-ray Computed Tomography on
Chemically Modified Wood
12th Annual Meeting of WSE, 12-13 Sep. 2016, Riga, Latvia
M. Sedighi Moghaddam, J. Van den Bulcke , M. Wålinder , P. Claesson, J. van Acker & A. Swerin
Dimensional stability Biological resistance High durability Higher hardness Wood modification Wood modification
Thermal Mechanical Chemical
Acetylation Furfurylation
Surface modification
Chemically modified wood samples
Acetylated southern yellow pine (SYP) 15.9% 22.2% acetyl content SYP 28% Furfurylated 45%
Weight percentage gain
Maple 32%
- Sedighi et al., Langmuir(2013), 29(39): 12145-12153.
BACKGROUND
ࡲ ࢎ ൌ ࡼࢽࢉ࢙ࣂ െ ࣋ࢎࢍ ࡲ࢝ሺ࢚ሻ
Multi-cycle Wilhelmy plate method
Contact angle Dynamic sorption
Swelling/capillarity
Dimensional stability Extractives dissolution
Swelling liquid/ Water
Chemically modified wood
Dynamic sorption
Chemically modified wood
Dynamic sorption
Acetylated SYP-22.2% Furfurylated SYP
Acetylation: reduces swelling
Correlate wetting properties to microstructure
X-ray computed tomography to visualize
anatomical details and to quantify micro- structural
properties of chemically modified wood
Microstructure
100 µm
Acetylated SYP Unmodified SYP
Tracheid Cell wall
100 µm
Unmodified SYP Furfurylated SYP, 45%
12
Microstructure
Microstructure- 3D & Quantification
100 µm
100 µm Porosity
Cell wall thickness Tracheid size
Microstructure- wetting properties
100 µm 100 µm SYPacet22.2 SYPctrl22.2 SYPacet15.9 SYPctrl15.9 Maplefurf32 Maplectrl SYPfurf45 SYPfurf28 SYPctrlMicrostructure- wetting properties
100 µm
100 µm
Acetylation: same porosity, reduces only swelling
Furfurylation: lower porosity, reduces both swelling
100 µm
100 µm 100 µm
Unmodified maple Furfurylated maple 32%
Vessel Fiber
Rays
100 µm
Microstructure-Cell wall thickness
100 µm
Conclusions
Wetting vs Microstructure
Acetylation Furfurylation
Swelling Capillarity Porosity
c a p il la ri ty porosity