Phenol-based resin adhesive from lignin pyrolysis and its preparation method

Patent metadata

Field	Value
Publication number	US-11214716-B2
Application number	US-202117195380-A
Country	US
Kind code	B2
Filing date	Mar 8, 2021
Priority date	Mar 10, 2020
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

The present invention relates to a phenol-based resin adhesive from lignin pyrolysis, comprising a polymer of phenol and formaldehyde from lignin pyrolysis, wherein the phenol from lignin pyrolysis comprises at least two phenols from lignin pyrolysis or at least two lignin-modified phenols from lignin pyrolysis. A repeat unit of the polymer of phenol and formaldehyde from lignin pyrolysis comprises at least two phenol units from lignin pyrolysis or at least two lignin-modified phenol units from lignin pyrolysis. According to the phenol-based resin adhesive from lignin pyrolysis in the present invention, by-products during the pyrolysis of lignin for power generation are used as raw materials, so it is environment-friendly and economical.

First claim

What is claimed is:

1. A resin adhesive based on a lignin pyrolytic phenol, comprising a polymer of lignin pyrolytic phenol-modified lignin and formaldehyde, wherein a repeat unit of the polymer comprises at least two kinds of lignin pyrolytic phenol groups in the lignin pyrolytic phenol-modified lignin; the lignin pyrolytic phenol groups are two or more selected from the group consisting of p-hydroxyphenyl phenol, guaiacyl phenol, syringyl phenol, phenol, cresol, pyrocatechol and pyrogallol; the lignin pyrolytic phenol is derived from lignin pyrolysis; and the lignin pyrolytic phenol-modified lignin is prepared by reacting a lignin and the lignin pyrolytic phenol under pH 10-13 at 60-95° C.

2. A method for preparing the resin adhesive based on the lignin pyrolytic phenol of claim 1 , comprising the following steps:
(1) pre-polymerizing a lignin pyrolytic phenol-modified lignin and a first formaldehyde solution under pH 12-14, so as to obtaining a prepolymer;
(2) reacting the prepolymer with a second formaldehyde solution under the action of a formaldehyde scavenger, vacuum distillating and obtaining the resin adhesive- based on the lignin pyrolytic phenol which a viscosity no less than 60 mPa*s;
wherein the mass ratio of formaldehyde in the first formaldehyde solution to that in the second formaldehyde solution is 3-4:1.

3. The method according to claim 2 , wherein the lignin pyrolytic phenol-modified lignin of step (1) is further obtained by a process comprising:
dissolving pyrolysis gas, that is generated by a pyrolysis of lignin at 300° C-800° C. for power generation, into water to obtain a phenol solution from the lignin pyrolysis; reacting the phenol solution and a lignin under pH 10-13 at 60-95° C. to obtain the lignin pyrolytic phenol-modified lignin.

4. The method according to claim 2 , wherein in steps (1) and (2), the reaction temperature is 75-90° C.

5. The method according to claim 2 , wherein the mass ratio of total formaldehyde in the first formaldehyde solution and the second formaldehyde solution to the lignin pyrolytic phenol groups of the lignin pyrolytic phenol-modified lignin is 1-1.5:1.

Assignees

• Univ Jiangnan

Inventors

• Shi Gang
• Li Ying
• Miao Hongyan
• Ni Caihua

Classifications

• C09J161/14 Primary

  Modified phenol-aldehyde condensates · CPC title

• C08G8/28

  Chemically modified polycondensates · CPC title

• C08G8/24 Primary

  with mixtures of two or more phenols which are not covered by only one of the groups C08G8/10 - C08G8/20 · CPC title

• C09J161/06 Primary

  of aldehydes with phenols · CPC title