First calcium, sugars, starches, and hemicellulose should be removed while keeping lignin mostly intact or even increasing it. This can be done with any method or series or combination of methods but I believe treating the wood with oxalic acid solution can accomplish all of these.
Next the cellulose should be partly dissolved to increase pore size in the wood and soften it, again preferably while keeping lignin intact as a structural component. This can be done with brief and/or low temperature hydroxide/urea solution. Keeping the temperature of this low will help prevent lignin removal or breakdown. Also this solution works best at low temperature and also freezing. This process should be carefully designed so as to not dissolve too much of the cellulose as to render the material fully dissolved or otherwise ruin the structure. In addition to this or alternatively, lignin can be removed from the oxalic acid treated wood. This would not infringe on the Hu patents because the wood is no longer "natural" after bieng treated with oxalic acid. However I believe the lignin is an important structural component in the matrix and likely shouldn't be removed for the best final product and rather a little of the cellulose should be removed and/or modified instead.
Next preferably the surface (or bulk) of the cellulose fibers should be converted into cellulose acetate (and/or nitrate if combustibility is desired). This will help water and humidity proof and adhere the cellulose fibers together in the compaction step.
Preferably next the matrix should be deacidified of any lingering acid with magnesium peroxide solution. This is a step taken from the art of paper preservation.
Finally the matrix should be compressed at around 750psi or higher preferably at elevated temperature preferably 212-300f or higher. The hope of this step is to get the cellulose acetate groups to bond the cellulose acetate (or plain celluose) fibers together
Each of these steps on their own are optional in this protocol but I believe the combination will give best results. For example natural wood can be treated to convert some of the cellulose to cellulose acetate and pressed. Or oxalic acid boil could be done and pressed right away. Or oxalic acid step, hydroxide step, then press, etc. Any or all of these steps can be done in any order or combination but the full protocol I believe will be optimal for many applications.
See the previous ultrawood post for more references.
Also you can make thin sheets or plates or any other shape with this method and combine them in any way including with a binder like a glue or catalyst like acetic acid or cellulose acetate or anything else or just inherently melding the cellulose acetate to eachother since this behaves like a polymer.
oxalic acid hydrolyzes starch and hemicellulose
https://www.google.com/url?sa=t&source=web&rct=j&url=http://proceedings.itb.ac.id/download.php%3Ffile%3DA13488.pdf%26id%3D2256%26up%3D1&ved=2ahUKEwjP6bzhxOPhAhWP0VQKHV__CSwQFjAAegQIBRAB&usg=AOvVaw1u6LLoTVU8RLbiPJvWMpvi
Next the cellulose should be partly dissolved to increase pore size in the wood and soften it, again preferably while keeping lignin intact as a structural component. This can be done with brief and/or low temperature hydroxide/urea solution. Keeping the temperature of this low will help prevent lignin removal or breakdown. Also this solution works best at low temperature and also freezing. This process should be carefully designed so as to not dissolve too much of the cellulose as to render the material fully dissolved or otherwise ruin the structure. In addition to this or alternatively, lignin can be removed from the oxalic acid treated wood. This would not infringe on the Hu patents because the wood is no longer "natural" after bieng treated with oxalic acid. However I believe the lignin is an important structural component in the matrix and likely shouldn't be removed for the best final product and rather a little of the cellulose should be removed and/or modified instead.
Next preferably the surface (or bulk) of the cellulose fibers should be converted into cellulose acetate (and/or nitrate if combustibility is desired). This will help water and humidity proof and adhere the cellulose fibers together in the compaction step.
Preferably next the matrix should be deacidified of any lingering acid with magnesium peroxide solution. This is a step taken from the art of paper preservation.
Finally the matrix should be compressed at around 750psi or higher preferably at elevated temperature preferably 212-300f or higher. The hope of this step is to get the cellulose acetate groups to bond the cellulose acetate (or plain celluose) fibers together
Each of these steps on their own are optional in this protocol but I believe the combination will give best results. For example natural wood can be treated to convert some of the cellulose to cellulose acetate and pressed. Or oxalic acid boil could be done and pressed right away. Or oxalic acid step, hydroxide step, then press, etc. Any or all of these steps can be done in any order or combination but the full protocol I believe will be optimal for many applications.
See the previous ultrawood post for more references.
Also you can make thin sheets or plates or any other shape with this method and combine them in any way including with a binder like a glue or catalyst like acetic acid or cellulose acetate or anything else or just inherently melding the cellulose acetate to eachother since this behaves like a polymer.
oxalic acid hydrolyzes starch and hemicellulose
https://www.google.com/url?sa=t&source=web&rct=j&url=http://proceedings.itb.ac.id/download.php%3Ffile%3DA13488.pdf%26id%3D2256%26up%3D1&ved=2ahUKEwjP6bzhxOPhAhWP0VQKHV__CSwQFjAAegQIBRAB&usg=AOvVaw1u6LLoTVU8RLbiPJvWMpvi
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