UltraWood: Polymerized super wood

So if you have heard of super wood or superwood, it is basically partially dissolved wood that is compressed to make it stronger than steel but much lighter.  Well of course I have an idea to improve it.

Enter ultrawood.  Besides adding preparation steps, the main added step is vacuum impregnation of a polymer somewhere between the initial hydroxide/urea (and/or other elements like oxalic acid pretreatment to remove calcium) step and the compression step.  After the wood is partially dissolved in the prep steps it has more porosity.  There may be a wash step after that or not, there may or may not be a de-lignan step of hydroxide/sulfite and then any polymer like epoxy or something else is vacuum impregnated into the voids.  Then it is compressed.  I think this method will not only fully prevent the 10% growth from humidity exposure that unpainted super wood is suseptible to, but also increase strength even higher.  Something like epoxy can increase strength whereas something like rubber latex might increase flexibility and toughness.  Also this impregnation might reduce the compression pressure and/or temperature needed to achieve a good product.  In super wood the bonds between cellulose have to be created by heat and compression, in vacuum impregnated version these bonds might become less important so the extreme pressure and elevated temperature may not be as important.

That bieng said of course other natural polymers (like cellulose acetate) can be used instead or addition to synthetic polymers for vacuum impregnation. Or a similar but slightly different thing can be done altogether.  Instead of vacuum impregnating with a premade polymer, what about a soak/boil step instead to make the cellulose itself more polymer like? Enter vinegar.  Yes the humble ingredient.  Simple acetic acid of any concentration preferably high concentration in water or another solvent or 100% glacial acetic acid (and/or not so simple acetic anhydride) or other more nasty things like trifluoriacetic acid can be used to turn the cellulose already present after the initial hydroxide/sulfite boil into a polymer itself or at least functionalize the surface of the cellulose fibers for better adherance after compression.  So basically you would have the same or slightly modified initial soak to increase wood porosity then you would boil or soak it in vinegar lets say for simplicity or anything else that achieves the same type of effect (namely neutralizing the OH groups to make it more unreactive to hydrogen bonding), then you would compress it.  So basically we are partially or fully converting the cellulose into cellulose acetate or cellulose nitrate or anything else) or just functionalizing the surface of the cellulose fibers to be more adherant and water repellant which is a sort of plastic polymer.  This will prevent expansion due to humidity and perhaps strengthen and/or toughen the material even more.

So the method I am going to pursue is soak in room temp 8%/8% hydroxide/urea then freeze 60 mins, boil/rinse/soak, then mabye remove lignan, boil/rinse/soak, soak in oxalic acid, boil in water rinse, boil in magnesium peroxide solution, short water boil rinse, boil in glacial acetic acid, boil in magnesium peroxide solution, boil in water rinse, heated press roughly 750psi and 212-300f.  This will in theory produce a long lasting water/humidity resistant, but still biodegradable product.

Simplified method I may use: (boil rinses probably between each step)
1. Soak in oxalic acid to remove calcium and hemicellulose and increase lignin.
2. Soak in room temp hydroxide/urea, freeze 60 mins.  Removes cellulose, enlarges pores.
3. soak in acetic acid optional sulfuric acid or other acetylating mix. Makes cellulose acetate.
4. Soak in magnesium bicarbonate to deacidify.
4. Press 750psi at 220-300f until proper thickness.

This does not infringe on the Liangbing Hu patents because his requires removing lignan from natural wood while keeping the cellulose structure substantially the same.  My method not only substantially changes the cellulose by a hydroxide/urea and/or oxalic acid pretreatment step, but this step also renders the wood no longer "natural wood", which also was a requisite to his claim.  So the chemically modified wood can be delignated if desired without infringing on the patent. However I feel keeping the structural component of the lignin would actually be a benefit to strength and toughness especially in light of the fact the cellulose will be significantly modified either in volumetric structure or at least surface structure to cellulose acetate.  Also lignin is removed at high temps so the hydroxide/urea step will not remove significant amounts of lignin.

Basically I am using cellulose acetate lamination process with deacidifying step of the magnesium bicarbonate.

super wood

trifluoroacetic acid to convert cellulose based matetials

surface functionalization of cellulose by plain acetic acid

acetate not good for adhesive, OH better

cellulose acetate lamination

deacidification of cellulose with magnesium bicarbonate


cellulose acetate lamination with and without acetone  500psi 300f

725psi 212f

delignified wood patent

strong and tough wood materials

flexible wood

8g naoh 8g urea 84g dih2o lignin not degraded

oxalic acid pretreatment

25% saturated magnesium bicarbonate sol

275ml dih20 100g oxalic acid 80c ish for 1hr (was 130c for 10 mins in paper) 9:07 to 10:07.  At end left with 75ml liquid.
Wood should have sunk to the bottom from bieng water logged. (using poplar wood).  Let soak in dih2o until next step.

magnesium bicarbonate:

oxalic acid precipitates not extracts lignin

Oxalic 1% pretreatment

oxalic increases lignin?

Yes lignin increases, hemicellulose decreases.

starch and sugar removal boiling 10min 80% ethanol and alpha amylase

20% hcl extraction  of starch

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