Modification of wood cell wall with water-soluble vinyl monomer to improve dimensional stability and its mechanism

Abstract A novel two-step combined treatment of poplar wood was developed to improve its dimensional stability. Maleic anhydride (MAN) was first employed to swell and bond to the wood cell wall, and then mixed monomers of glycidyl methacrylate/methyl methacrylate (GMA/MMA) were grafted to the cell wall through the chemical reaction with MAN within the wood cell lumen. The results of scanning electron microscopy and energy dispersive X-ray apparatus (SEM-EDX) and Fourier transform infrared spectroscopy (FTIR) analyses indicate that MAN penetrated and chemically bonded to the cell wall causing 9% volume swelling, and the copolymer from GMA/MMA monomers was grafted onto the wood cell wall, resulting in the improved interfacial compatibility between the polymer and wood matrix. The dimensional stability of poplar wood modified by the combined two-step treatment was remarkably improved compared with that of untreated poplar wood. The combination treatment of wood employed in this study proved to be more effective for improving the dimensional stability than treatment with PEG-1000 aqueous solution with 30% concentration.

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Faculty Opinions recommendation of Wood cell-wall structure requires local 2D-microtubule disassembly by a novel plasma membrane-anchored protein.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.4116957.3896055 ◽

2010 ◽

Author(s):

Clive Lloyd

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Wood Cell Wall ◽

Cell Wall Structure ◽

Wall Structure

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Acetyl Group Distribution in Acetylated Wood Investigated by Microautoradiography

Holzforschung ◽

10.1515/hf.2001.045 ◽

2001 ◽

Vol 55 (3) ◽

pp. 270-275 ◽

Cited By ~ 4

Author(s):

Marie Rosenqvist

Keyword(s):

Cell Wall ◽

Weight Gain ◽

Acetic Anhydride ◽

Wood Cell Wall ◽

Environmental Scanning Electron Microscopy ◽

Environmental Scanning ◽

Accurate Information ◽

Concentration Gradients ◽

Good Opportunity ◽

Acetyl Group

Summary Sapwood of Scots pine (Pinus silvestris L.) was acetylated with 14C- and 3H-labelled acetic anhydride. The distribution of acetyl groups was investigated with microautoradiography and microautoradiographs were evaluated with ESEM, Environmental Scanning Electron Microscopy. The investigation showed that the impregnation of wood with radioisotope-labelled substances provides a good opportunity to investigate the location of substances covalently bonded to the wood material. Introduced 14C-labelled acetyl groups show an even distribution in the wood cell wall, with no discernible concentration gradients at acetylation levels of about 5, 15 and 20% weight gain. 3H-labelled acetyl groups show an even distribution in the wood cell wall at 15 and 20% weight gain, with no discernible concentration gradients. At the 5% weight gain level, however, an uneven distribution of 3H-labelled acetyl groups over the cell wall is observed. Nevertheless, the unevenness is random and no concentration gradient is discernible at this level. 3H with a relatively high resolution, 0.5–1 μm, compared to 14C with a resolution of 2–5 μm, gives more accurate information about where exactly the acetyl groups are situated in the wood cell wall. Acetic anhydride was evenly distributed when a full impregnation procedure was used. The chemical and physical properties of acetic anhydride allow a uniform penetration into the pine cell wall and a complete acetylation takes place when the specimens are heated.

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Isolation and Properties of a Macromolecular, Water-Soluble, Immuno-Adjuvant Fraction from the Cell Wall of Mycobacterium smegmatis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.69.4.851 ◽

1972 ◽

Vol 69 (4) ◽

pp. 851-854 ◽

Cited By ~ 86

Author(s):

A. Adam ◽

R. Ciorbaru ◽

J.-F. Petit ◽

E. Lederer

Keyword(s):

Cell Wall ◽

Mycobacterium Smegmatis ◽

Water Soluble

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Enhancement of the physical and mechanical properties of wood using a novel organo-montmorillonite/hyperbranched polyacrylate emulsion

Holzforschung ◽

10.1515/hf-2020-0042 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Jianfeng Xu ◽

Xiaoyan Li ◽

Ling Long ◽

Ru Liu

Keyword(s):

Mechanical Properties ◽

Cell Wall ◽

Pinus Radiata ◽

Wood Sample ◽

Wood Cell Wall ◽

Physical And Mechanical Properties ◽

Radiata Pine ◽

Compact Structure ◽

Populus Cathayana ◽

Modified Wood

AbstractIn this work, a novel waterborne hyperbranched polyacrylate (HBPA) dispersed organo-montmorillonite (OMMT) emulsion was synthesized and used for the treatment of wood in a vacuum environment in order to enhance the physical and mechanical properties of the wood. The sapwood of Cathay poplar (Populus cathayana Rehd.) and Radiata pine (Pinus radiata D.Don) were used as the samples for experimentation. The results showed that the physical and mechanical properties of the wood improved significantly due to the successful penetration of the OMMT and HBPA into the wood cell wall. From it was also observed that OMET completely exfoliated from the HBPA matrix and formed a hydrophobic film covering on the inside walls of the cell lumen. Further, it was observed that the poplar sample displayed better mechanical properties than the pine sample because the pine has a more compact structure when compared to poplar and contains rosin. Furthermore, it was also observed that the mechanical properties of the modified wood sample gradually improved with an increase in the concentration of the emulsion. However, excessive concentration (>4 wt%) did not lead to further improvement.

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