Furfuryl alcohol impregnation for improved plasticization and fixation during the densification of wood

Abstract The densification of wood leads to better mechanical properties, e.g., an increased hardness and dimensional stability. However, densified or shaped wood in contact with water springs back into its original shape without fixation. Hence, the aim of this study was the development of a combined densification and fixation procedure. Beech wood samples (Fagus sylvatica L.) were impregnated with a solution consisting of furfuryl alcohol and maleic anhydride. The compression of these impregnated samples to approximately 30% followed by a curing process in a heating press resulted in a significant increase of hardness and dimensional stability. The spring-back-effect was clearly reduced by the in situ polymerization of the furfuryl alcohol solution to furan resins.

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Mechanical Characterization of Polymer Nanowires Using MEMS

Materials, Nondestructive Evaluation, and Pressure Vessels and Piping ◽

10.1115/imece2006-14859 ◽

2006 ◽

Cited By ~ 1

Author(s):

B. A. Samuel ◽

Bo Yi ◽

R. Rajagopalan ◽

H. C. Foley ◽

M. A. Haque

Keyword(s):

Mechanical Properties ◽

Tensile Testing ◽

Furfuryl Alcohol ◽

Mechanical Characterization ◽

Uniaxial Tensile ◽

Testing Device ◽

Uniaxial Tensile Testing ◽

Polymer Nanowires

We present results on the mechanical properties of single freestanding poly-furfuryl alcohol (PFA) nanowires (aspect ratio > 50, diameters 100–300 nm) from experiments conducted using a MEMS-based uniaxial tensile testing device in-situ inside the SEM. The specimens tested were pyrolyzed PFA nanowires (pyrolyzed at 800° C).

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Combined Chemical Modification of Bamboo Material Prepared Using Vinyl Acetate and Methyl Methacrylate: Dimensional Stability, Chemical Structure, and Dynamic Mechanical Properties

Polymers ◽

10.3390/polym11101651 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1651 ◽

Cited By ~ 4

Author(s):

Saisai Huang ◽

Qiufang Jiang ◽

Bin Yu ◽

Yujing Nie ◽

Zhongqing Ma ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Chemical Modification ◽

Methyl Methacrylate ◽

Vinyl Acetate ◽

Dimensional Stability ◽

Chemical Structure ◽

In Situ Polymerization ◽

Dynamic Mechanical Properties

Acetylation and in situ polymerization are two typical chemical modifications that are used to improve the dimensional stability of bamboo. In this work, the combination of chemical modification of vinyl acetate (VA) acetylation and methyl methacrylate (MMA) in situ polymerization of bamboo was employed. Performances of the treated bamboo were evaluated in terms of dimensional stability, wettability, thermal stability, chemical structure, and dynamic mechanical properties. Results show that the performances (dimensional stability, thermal stability, and wettability) of bamboo that was prepared via the combined pretreatment of VA and MMA (VA/MMA-B) were better than those of raw bamboo, VA single-treated bamboo (VA-B), and MMA single-treated bamboo (MMA-B). According to scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses, VA and MMA were mainly grafted onto the surface of the cell wall or in the bamboo cell lumen. The antiswelling efficiency and contact angle of VA/MMA-B increased to maximum values of 40.71% and 107.1°, respectively. From thermogravimetric analysis (TG/DTG curves), the highest onset decomposition temperature (277 °C) was observed in VA/MMA-B. From DMA analysis, the storage modulus (E’) of VA/MMA-B increased sharply from 15,057 Pa (untreated bamboo) to 17,909 Pa (single-treated bamboo), and the glass transition temperature was improved from 180 °C (raw bamboo) to 205 °C (single-treated bamboo).

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An effective technique for constructing wood composite with superior dimensional stability

Holzforschung ◽

10.1515/hf-2019-0176 ◽

2020 ◽

Vol 74 (5) ◽

pp. 435-443

Author(s):

Xiaoshuai Han ◽

Zhenxing Wang ◽

Qinqin Zhang ◽

Junwen Pu

Keyword(s):

Mechanical Properties ◽

Dimensional Stability ◽

High Performance ◽

Low Cost ◽

Sem Analysis ◽

Wood Composite ◽

Engineering Structures ◽

Natural Wood ◽

Dimensional Instability

AbstractFast-growing wood is an abundant and low-cost material and is widely used for structural building and furniture construction. However, inferior mechanical properties and dimensional instability limit its application in advanced engineering structures. Herein, we developed a simple, effective and “green” method to transform bulk poplar into a high-performance wood composite. The wood composite was prepared by the impregnation of the itaconic acid (IA) solution acting as a grafting anchor into the wood matrix, followed by in situ polymerization of styrene upon heating to form a hydrophobic polymer within the wood scaffold. Scanning electron microscope (SEM) analysis revealed that hydrophobic polystyrene (PS) was deposited in wood cell walls and lumens, leading to a reduced water uptake and remarkably enhanced dimensional stability, as well as generally improved mechanical properties. In addition, the PS generated improvement in the thermal stability of the wood composite in comparison with that of natural wood (W).

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In Situ Polymerization of Furfuryl Alcohol with Ammonium Dihydrogen Phosphate in Poplar Wood for Improved Dimensional Stability and Flame Retardancy

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.7b03518 ◽

2018 ◽

Vol 6 (3) ◽

pp. 3349-3357 ◽

Cited By ~ 28

Author(s):

Lizhuo Kong ◽

Hao Guan ◽

Xiaoqing Wang

Keyword(s):

Flame Retardancy ◽

Dimensional Stability ◽

Furfuryl Alcohol ◽

In Situ Polymerization ◽

Dihydrogen Phosphate ◽

Ammonium Dihydrogen Phosphate ◽

Poplar Wood

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Improvement of beech wood properties by in situ formation of polyesters of citric and tartaric acid in combination with glycerol

Holzforschung ◽

10.1515/hf-2017-0081 ◽

2018 ◽

Vol 72 (4) ◽

pp. 291-299 ◽

Cited By ~ 11

Author(s):

Clément L’Hostis ◽

Marie-France Thévenon ◽

Emmanuel Fredon ◽

Philippe Gérardin

Keyword(s):

Thermal Degradation ◽

Tartaric Acid ◽

Dimensional Stability ◽

Heating Temperature ◽

Beech Wood ◽

Treated Wood ◽

Wood Properties ◽

Decay Resistance ◽

Attenuated Total Reflection

AbstractBeech wood has been treated by impregnation followed by heating at various temperatures with solutions containing citric acid (CA) or tartaric acid (TA) alone or in combination with glycerol (G), i.e. with G+CA and G+TA. The resulting modified woods were tested in terms of resistance to leaching, durability and dimensional stability. These properties are improved as a function of heating temperature, which leads to higher levels of poly-esterification involving grafting onto wood simultaneously with thermal degradation of wood. Dimensional stability of all treated wood was increased, but glycerol does not have a positive effect with this regard. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy contributed to understanding the effects of the different treatments.In situpolymerization of G+TA at 140°C increased the bending resistance, while G+CA polymerization does not compensate notably the mechanical weakness induced by thermal degradation of wood at higher temperatures. However, G+CA treatment is more efficient regarding leaching and decay resistance, than that with G+TA.

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Dynamics of Nanoparticle Chain Aggregates of Carbon Under Tension

MRS Proceedings ◽

10.1557/proc-778-u4.4 ◽

2003 ◽

Vol 778 ◽

Author(s):

Rajdip Bandyopadhyaya ◽

Weizhi Rong ◽

Yong J. Suh ◽

Sheldon K. Friedlander

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

Polymer Film ◽

Elastic Behavior ◽

Small Strains ◽

Transmission Electron ◽

Chain Aggregates ◽

Nanoparticle Chains ◽

Reinforcing Filler

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.

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