US 12,168,727 B2
Transparent wood composite, systems and method of fabrication
Liangbing Hu, Potomac, MD (US); Mingwei Zhu, Nanjing (CN); Tian Li, West Lafayette, IN (US); Amy S. Gong, Potomac, MD (US); and Jianwei Song, College Park, MD (US)
Assigned to UNIVERSITY OF MARYLAND, COLLEGE PARK, College Park, MD (US)
Filed by UNIVERSITY OF MARYLAND, COLLEGE PARK, College Park, MD (US)
Filed on May 2, 2022, as Appl. No. 17/734,283.
Application 17/734,283 is a division of application No. 16/074,148, abandoned, previously published as PCT/US2017/016490, filed on Feb. 3, 2017.
Claims priority of provisional application 62/291,151, filed on Feb. 4, 2016.
Prior Publication US 2022/0259412 A1, Aug. 18, 2022
Int. Cl. C08L 1/02 (2006.01); B27K 3/02 (2006.01); B27K 3/15 (2006.01); C08J 9/26 (2006.01); C08J 9/42 (2006.01); H01L 31/0216 (2014.01); H01L 31/0304 (2006.01); H01L 31/18 (2006.01)
CPC C08L 1/02 (2013.01) [B27K 3/0207 (2013.01); B27K 3/15 (2013.01); C08J 9/26 (2013.01); C08J 9/42 (2013.01); H01L 31/02168 (2013.01); H01L 31/0304 (2013.01); H01L 31/184 (2013.01); B27K 2240/10 (2013.01); C08J 2201/0422 (2013.01); C08J 2301/02 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method of fabrication of a wood-based light transmitting system, comprising steps of:
(a) pre-cutting a wood block from a natural wood in a pre-determined angular relationship to natural internal channels of the natural wood to obtain a pre-cut wood block, the natural internal channels having walls formed from cellulose-containing material and being filled with lignin,
(b) removing the lignin from natural internal channels of said pre-cut wood block, thus forming a lignin-devoid wood block, and
(c) sequentially infiltrating said natural internal channels in said lignin-devoid wood block with a filling polymer so as to obtain a wood composite member,
wherein a refractive index of the filling polymer is such that the wood composite member is transparent and has a transmittance from 85% to 95% for light having a wavelength in a range of 400 nm to 1100 nm,
wherein the filling polymer is polyvinylpyrrolidone,
wherein the transparent wood composite member has an optical haze from 85% to 100% for light having a wavelength in the range of 400 nm to 1100 nm,
wherein the step (b) comprises:
preparing a lignin removal solution by mixing a solution of NaOH in deionized water, and a solution of Na2SO3 in deionized water,
boiling said pre-cut wood block in said lignin removal solution,
rinsing said pre-cut wood block in hot distilled water, and
boiling said rinsed pre-cut wood block in a bleaching solution containing a solution of H202 in distilled water until a color of the pre-cut wood block disappears,
thereby obtaining the lignin-devoid wood block; and
wherein the step (c) comprises:
immersing said lignin-devoid wood block in a container of said filling polymer in a liquid phase thereof,
degassing said liquid filling polymer under a pressure of 200 Pa,
applying atmospheric pressure to the liquid filling polymer to promote infiltration of the filling polymer into the internal channels of the lignin-devoid wood block,
repeating said atmospheric pressure application at least once, thus obtaining a liquid polymer infiltrated wood block,
maintaining the liquid polymer infiltrated wood block in said container undisturbed at a temperature of 30° C.-60° C. until the filling polymer solidifies, thus obtaining a solid polymer infiltrated wood block, and
removing said solid polymer infiltrated wood block from the container, thus obtaining said transparent wood composite member.