Patent Showcase | A Method for Synergistic Degradation of Formaldehyde in Engineered Wood Products

[Application Number] CN201710017229.X [Application Date] 2017-01-05

[Publication Number] CN106700784A [Publication Date] 2017-05-24

[Applicant] Nanjing Forestry University [Address] No. 159, Longpan Road, Nanjing, Jiangsu Province, 210037, China

[Inventors] Pan Mingzhu; Huang Huiling; Zhao Guomin; Li Wendi; Zhang Minzhi

[Country/Province Code] 32

[Abstract] This invention discloses a method for synergistic degradation of formaldehyde in engineered wood products. Specifically, zinc acetate and ethanol are added to nanocrystalline cellulose colloid, followed by sol-gel to obtain a nanocrystalline cellulose/zinc oxide composite colloid. This composite colloid is then dispersed in a water-soluble polyacrylic acid coating to prepare a water-soluble formaldehyde-reducing polyacrylic acid coating. This coating is then sprayed onto the surface of the engineered wood product, dried, and the formaldehyde-reducing engineered wood product is obtained. The formaldehyde concentration of the engineered wood product reduced by 65-88% after coating with the water-soluble formaldehyde-reducing polyacrylic acid coating. This method uses the water-soluble polyacrylic acid coating as a carrier, utilizing the high adsorption capacity of nanocrystalline cellulose and the photocatalytic properties of nano-zinc oxide to synergistically degrade formaldehyde released from the engineered wood product. Furthermore, it improves the bonding performance between the polyacrylic acid coating and the engineered wood product. The process is simple and easy to control.

[Claim 1] A method for synergistic degradation of formaldehyde in engineered wood products, characterized by the following steps: (1) Weighing nanocrystalline cellulose and distilled water at a mass ratio of 0.2–0.6:100, mixing thoroughly, and sonicating to obtain a nanocrystalline cellulose colloid with a mass fraction of 0.2–0.6%; (2) Weighing the nanocrystalline cellulose colloid, zinc acetate, and anhydrous ethanol from step (1) at a mass ratio of 1.3:(1.6–3.6):(80–120), and adding the nanocrystalline cellulose colloid and zinc acetate sequentially to the anhydrous ethanol, adjusting the pH of the solution to 8–10 with sodium hydroxide, and reacting at 70–80°C for 4–5 h to obtain nanocrystalline cellulose/zinc oxide. (3) Add the nanocrystalline cellulose/zinc oxide composite colloid prepared in step (2) to the water-soluble polyacrylic acid coating, sonicate for 15-30 min, and then stir at 25-30℃ for 12-24 h to form a water-soluble formaldehyde-reducing polyacrylic acid coating, and make the mass ratio of nanocrystalline cellulose/zinc oxide and polyacrylic acid in the water-soluble formaldehyde-reducing polyacrylic acid coating 1-7:100; (4) Spray the water-soluble formaldehyde-reducing polyacrylic acid coating prepared in step (3) onto the surface of the artificial board, dry it at <60℃ to prepare a formaldehyde-reducing artificial board, and make the thickness of the polyacrylic acid coating in the formaldehyde-reducing artificial board 0.1-0.25 μm.