Wood modifications for valued-added applications using nanotechnology-based approaches

Liste des illustrations

• Figure 1.1 Idealized structure of a montmorillonite layer showing two tetrahedral-site sheets fused to an octahedral-site sheet (2:1 type) [Outubuddin and Fu 2002, Ray and Okamoto 2003].
• Figure 1.2 Processing challenge for exfoliated nanoclay [Dennis et al., Southern Clay Products].
• Figure 1.3 Orientations of alkylammonium ions in the galleries of clay layers with different layer charge densities [Qutubuddin and Fu 2002].
• Figure 1.4 Schematic illustrations of three types of polymer-clay composites.
• Figure 1.5 Four samples of X-ray diffraction [Dennis et al, Southern Clay Products].
• Figure 1.6 TEM imagine of PA6/nanoclay by extruder process [Dennis et al, Southern Clay Products].
• Figure 1.7 Dispersion mechanism of nanoclay to a polymer.
• Figure 1.8 Model of alkylammonium – exchanged clay swollen by monomer or polymer precursors such as styrene, ε-caprolactam, and epoxide [Qutubuddin and Fu 2003].
• Figure 1.9 Relationship between the dispersion and the mechanical properties [Dennis et al Southern Clay Products, Inc.].
• Figure 1.10 Effect of relative humidity on O₂ transmission at various clay loadings [Dennis et al, Southern Clay Products, Inc.].
• Figure 1.11 Water vapour transmission vs. clay content [Dennis et al, Southern Clay Products, Inc.].
• Figure 2.1 Survey of the experimental procedure.
• Figure 2.2 (a)‑Aspen green log before cutting.
• Figure 2.2 (b) Sketch showing method of cutting the bolt and marking the sticks. For example in lumber AS01E1 (stands for: A – aspen, S – sapwood, 01 – log lumber, E – eastern direction, 1 - lumber number) and AH01-1 (Stands for: A – aspen, H – heartwood, 01 – log number, 1 – heartwood lumber number), respectively.
• Figure 2.2 Wood sample cutting design (a) Aspen green log before cutting, (b) Sketch showing method of cutting up the bolt and marking the sticks, (c) Samples end match.
• Figure 2.3 Forintek staff is preparing specimens with Wood-Mizer.
• Figure 2.4 Preparation of kiln drying green aspen lumbers.
• Figure 2.5 Equipment of melamine – urea – formaldehyde resin synthesis.
• Figure 2.6 Ball mill equipment.
• Figure 2.7 Desintegrator for high speed mixing MUF resin with nanoclay.
• Figure 2.8 Zetarsizer Nano ZS.
• Figure 2.9 Principle of color meaurement.
• Figure 2.10 Calculation of color differences.
• Figure 2.11 Color-guide BYK-Gardner GmbH equipment
• Figure 2.12 Electron Microprobe Analyzer (CAMECA S×100, France).
• Figure 3.1 TGA results of received nanoclays, NF1 - Cloisite®30B, NF2 - Claytone®APA, NF3 – Cloisite®Na⁺
• Figure 3.2 X-Ray diffraction analysis of the pristine nanofiller before and after the ball-mill treatment.
• Figure 3.3 SEM pictures of layered aluminium silicate (a) NF1, (b) ball-milled NF1.
• Figure 3.4 X-Ray composition analysis of clay received and ball mill treated clay (a) NF2, and (b) milled NF2.
• Figure 3.5 DSC thermograms using different heating rates for (a) MUF resin, (b) 1% NF2/MUF, and (c) 1% NF2-m/MUF resins.
• Figure 3.6 Activation energy dependency on the degree of conversion for the MUF resin, and MUF resin mixed with different nanoclays.
• Figure 3.7 Activation energy dependency on the degree of conversion for the MUF resin, 1% NF2/MUF, and 1% NF2-m/MUF resins.
• Figure 3.8 Storage modulus of MUF, 1% NF1/MUF, 1% NF2/MUF and 1% NF3/MUF nanocomposites.
• Figure 3.9 Loss tangent of MUF, 1% NF1/MUF, 1% NF2/MUF and 1% NF3/MUF nanocomposites.
• Figure 3.10 Storage modulus of clay/MUF and ball mill ground clay/MUF nanocomposites.
• Figure 3.11 Loss tangent of clay/ MUF and ball mill ground clay/MUF nanocomposites.
• Figure 4.1 Density profiles of MUF and nanoclay/MUF treated and untreated aspen wood after hot-pressing: NF1, NF2 and NF3 are montmorillonite nanofillers; NF1-m, NF2-m and NF3-m are milled nanofillers.
• Figure 4.2 Mechanical properties of aspen and impregnated aspen with MUF and 1 wt % montmorillonite/MUF. a) Brinell hardness, b) Wear resistance of MUF and nanoclay/MUF (100cycles/300cycles/500cycle) treated samples NF1, NF2 and NF3 are montmorillo
• Figure 4.3 Relationship between strength at rupture and elasticity modulus (MOR/MOE) of aspen and impregnated aspen with MUF and montmorillonite/MUF. NF1, NF2 and NF3 are montmorillonite nanofillers; NF1-m, NF2-m and NF3-m are milled nanofillers.
• Figure 5.1 Scanning electron microscopy photographs of (a) control wood samples, (b) MUF-treated wood sample, containing 42.1% polymer, (c) NF1/MUF-treated wood sample, NF1/MUF content 40.9%, (d) NF2/MUF-treated wood sample, containing 40.6% NF2/MUF, and (e) NF3/MUF-treated wood sample, containing 35.6% NF3/MUF.
• Figure 5.2 Electron Microprobe Analysis of NF2/MUF treated wood, (a) transversal face, and (b) Al elemental distribution.
• Figure 5.3 Water repellency efficiency.
• Figure 5.4 Antiswelling efficiency, (a) tangential direction and radial direction, (b) ASE in volume.
• Figure 6.1 X-ray diffraction of the pristine nanofiller before and after the ball-mill treatment.
• Figure 6.2 X-ray composition analysis of the hydrophobic nanoclay NF1, NF2 before (a,c) and after ball-milling treatment (b,d), respectively.
• Figure 6.3 SEM photographs of the fracture surface of (a) untreated, (b) MUF treated, (c) NF3/MUF treated, and (d) NF2/MUF treated wood. (e) and (f) are trace of nanoclay in the nanoclay/MUF treated wood.
• Figure 6.4 Electron microprobe analysis of aluminum distribution in the NF2/MUF treated wood: (a) transverse image, and (b) Al distribution.
• Figure 6.5 TEM photographs of (a) MUF and (b) NF2/MUF treated wood cell wall.
• Figure 6.6 Storage modulus E’ profiles of pure control wood, and MUF, NF2/MUF and NF3/MUF impregnated wood.
• Figure 6.7 tan δ profiles of pure control wood, MUF, NF2/MUF and NF3/MUF impregnated wood
• Figure 7.1 Image of Wincell analysis window.
• Figure 7.2 Ultrathin sections of the walls of aspen vessel with various wall layers: ML (middle lamella), M (compound middle lamella), P (primary wall, S1 (the out layer of secondary wall), S2 (the centre layer of secondary wall), T (tertiary wall).
• Figure 7.3 Distribution of montmorillionite nanoparticles along the transverse ultrastructure of aspen/MUF/nanocomposites.
• Figure 7.4 Photographs of AFM analysis control sample and treated aspen samples, a) aspen wood, resolution with axis X 0.5 µm/div and axis Z 200 nm/div.
• Figure 7.4 b) MUF impregnated aspen wood, resolution with axis X 100 nm/div and axis Z 100 nm/div.
• Figure 7.4 c) MUF_NF1/aspen wood, resolution axis X 2 µm/div and axis Z 200 nm/div
• Figure 7.4 d) MUF_NF1/aspen wood, resolution with axis X 0.5 µm/div and axis Z 100 nm/div.
• Figure 7.4 e) MUF_NF2/aspen wood, resolution with axis X 100 nm/div and axis Z 50 nm/div.
• Figure 7.4 f) MUF_NF3/aspen wood, resolution with axis X 0.2 μm/div and axis Z 50 nm/div
• Figure I 1 SEM analysis (transverse section) of pure aspen wood.
• Figure I 2 SEM analysis (transverse section) of MUF treated wood.
• Figure I 3 SEM analysis (transverse section) of MUF/NF2/wood nanocomposites.
• Figure I 4 SEM analysis (transverse section) of MUF/NF2/wood nanocomposites at higher magnification with rough surface (microscale).
• Figure I 5 SEM analysis (transverse section) of MUF/NF2_bm/wood nanocomposites at high magnification with fine surface (microscale).
• Figure II 1 EPMA observation (transverse section) with high magnification (microscale).
• Figure II 2 EPMA observation of aluminium element distribution (transverse section, cell wall) with high magnification (microscale).
• Figure II 3 EPMA observation of aluminium element distribution (transverse section, cell wall, cell lumen).
• Figure II 4 EPMA observation (tangential section) with high magnification (microscale).
• Figure II 5 EPMA observation aluminium element distribution (tangential section) with high magnification, color picture (microscale).
• Figure II 6 EPMA observation of aluminium element distribution (tangential section) with high magnification, black and white (microscale).
• Figure II 7EPMA observation (radial section) with high magnification (microscale).
• Figure II 8 EPMA observation of aluminium element distribution (radial section) with high magnification, color picture (microscale).
• Figure II 9 EPMA observation of aluminium element distribution (radial section) with high magnification, black and white (microscale).
• Figure II 10EPMA observation (radial section) with higher magnification (microscale).
• Figure II 11 EPMA observation of aluminium element distribution (radial section) with higher magnification, color picture (microscale).
• Figure II 12 EPMA observation of aluminium element distribution (radial section) with higher magnification, black and white (microscale).
• Figure III 1 TEM observation of MUF/NF2/wood nanocomposite (transverse section, microscale).
• Figure III 2 TEM observation of MUF/NF2/wood nanocomposite (transverse section, microscale).
• Figure III 3 TEM observation of MUF/NF2/wood nanocomposite (transverse section, cell wall, nanoscale).
• Figure III 4 TEM observation of MUF/NF2/wood nanocomposite (transverse section, cell wall, nanoscale).
• Figure III 5 TEM observation of MUF/NF2/wood nanocomposite (transverse section, cell wall part, nanoscale).
• Figure III 6 TEM observation of MUF/NF2/wood nanocomposite (transverse section part M, ML layers, microscale magnification).
• Figure III 7 TEM observation of MUF/NF2/wood nanocomposite (transverse section, part M, ML layers, nanoscale).
• Figure III 8 TEM observation of MUF/NF2/wood nanocomposite (transverse section, part M, ML layers, nanoscale).
• Figure III 9 TEM observation of MUF/NF2/wood nanocomposite (transverse section, part M, ML layers nanoscale).