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CN-122011314-A - Preparation method of organic silicon modified formaldehyde-free amino resin and wood modification application thereof

CN122011314ACN 122011314 ACN122011314 ACN 122011314ACN-122011314-A

Abstract

The invention relates to the technical field of amino resin and discloses a preparation method of organic silicon modified formaldehyde-free amino resin and wood modification application thereof, wherein the preparation method comprises the steps of 1) adding glyoxal into a reaction kettle, adjusting the pH value to 4.0-6.0, adding melamine, heating to 40-50 ℃, reacting for 30-60 min, 2) adding urea and a dispersing agent for the first time into the reaction kettle, heating to 50-70 ℃ and reacting for 30-60 min, 3) adding urea, organic silicide and deionized water for the second time into the reaction kettle, reacting for 1-3 h, 4) adding a flame retardant into the reaction kettle, stirring for 30min, adjusting the pH value to 7.0-9.0, and improving the flexibility and the shock resistance of the resin and the toughness and the quality and endowing the flame retardant function by controlling the reaction condition and the raw material addition sequence.

Inventors

  • SUN BAILING
  • CHAI YUBO
  • LV WENHUA
  • WANG XIAOQING
  • HU JIHANG
  • JIANG PAN
  • LI YUANG

Assignees

  • 中国林业科学研究院木材工业研究所

Dates

Publication Date
20260512
Application Date
20260228

Claims (10)

  1. 1. The preparation method of the organic silicon modified formaldehyde-free amino resin is characterized by comprising the following preparation steps: 1) Adding glyoxal into a reaction kettle, regulating the pH value of the glyoxal to 4.0-6.0 by utilizing a pH regulator, adding melamine, uniformly stirring the glyoxal and the melamine, heating to 40-50 ℃ and reacting for 30-60 min; 2) Adding primary urea and a dispersing agent into the reaction kettle, heating to 50-70 ℃ and reacting for 30-60 min; 3) Adding urea, organic silicide and deionized water for the second time into the reaction kettle, and reacting for 1-3 hours; 4) And adding a flame retardant into the reaction kettle, stirring for 30min, regulating the pH value to 7.0-9.0 by using a pH regulator, and cooling and discharging to obtain the organosilicon modified formaldehyde-free amino resin.
  2. 2. The method for preparing the organic silicon modified formaldehyde-free amino resin according to claim 1, wherein the organic silicon modified formaldehyde-free amino resin comprises 20% -35% of glyoxal, 5% -20% of melamine, 10% -40% of urea, 5% -20% of organic silicide, 2% -10% of dispersing agent and 1% -5% of flame retardant according to the mass percentage of components, and the urea comprises first urea and second urea.
  3. 3. The method of preparing a silicone-modified formaldehyde-free amino resin according to claim 1, wherein in the preparing step 3), the organic silicide includes one or more of sodium methyl silicate, hydroxyl-terminated polydimethylsiloxane, vinyltriethoxysilane, and vinyltrimethoxysilane.
  4. 4. The method for preparing the silicone-modified formaldehyde-free amino resin according to claim 1, wherein in the preparing step 2), the dispersant comprises one or more of polyvinyl alcohol, polyethylene glycol, ethylene glycol, glycerol, isopropanol, pentaerythritol, ethanol, and methanol.
  5. 5. The method for preparing the organosilicon modified formaldehyde-free amino resin according to claim 1, wherein in the preparation step 1) and the preparation step 4), the pH regulator is one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium silicate and potassium silicate.
  6. 6. The method for producing a silicone-modified formaldehyde-free amino resin according to claim 1, wherein in the step 4), the flame retardant comprises one or a combination of two or more of ammonium phosphate, diammonium phosphate, monoammonium phosphate, ammonium pyrophosphate, boric acid, and borax.
  7. 7. The method for producing a silicone-modified formaldehyde-free amino resin according to claim 1, wherein the mass ratio of the first urea to the second urea is (2-3): 1.
  8. 8. The use of the organosilicon-modified formaldehyde-free amino resin prepared by the method for preparing an organosilicon-modified formaldehyde-free amino resin according to any one of claims 1 to 7 for modifying wood.
  9. 9. Use of the silicone-modified formaldehyde-free amino resin according to claim 8 for modifying wood, comprising the following modification steps: 1) Obtaining raw wood, drying the raw wood in the shade until the water content is 60% -20%, and then preparing the raw wood into a plate; 2) Immersing the plate in an organosilicon modified formaldehyde-free amino resin, placing the organosilicon modified formaldehyde-free amino resin and the plate in vacuum pressurizing equipment, and vacuum pressurizing and impregnating the plate by utilizing the vacuum pressurizing equipment so as to enable the organosilicon modified formaldehyde-free amino resin to permeate into the plate to reach a set permeation quantity; The vacuum pressurizing equipment is used for vacuum pressurizing the organosilicon modified formaldehyde-free amino resin impregnated wood in a vacuum range of-0.05 MPa to-0.1 MPa, and the pressurizing range is 0.6MPa to 2.0MPa; 3) And taking out the plate from the organic silicon modified formaldehyde-free amino resin, drying the plate-shaped wood in the shade for 2-3 days, and drying the plate-shaped wood at the drying temperature of 40-80 ℃ until the water content of the plate-shaped wood is 5-10%.
  10. 10. The use of the silicone-modified formaldehyde-free amino resin of claim 9 for modifying wood, wherein the raw wood is softwood.

Description

Preparation method of organic silicon modified formaldehyde-free amino resin and wood modification application thereof Technical Field The invention relates to the technical field of amino resins, in particular to a preparation method of an organosilicon modified formaldehyde-free amino resin and a wood modification application thereof. Background The wood resin impregnation modification technology is an industrially applied wood modification method, can effectively improve the dimensional stability, mechanical strength and the like of the artificial forest, and is an important way for realizing the value-added utilization of the artificial forest. Recently, along with the enhancement of environmental protection consciousness of people, the traditional formaldehyde resin wood modification technology has poor environmental protection property due to formaldehyde, and the application range of modified boards is limited to a certain extent, so that the development of formaldehyde-free wood modification technology becomes an urgent requirement for industry development. In the prior art, a wood modifier melamine-urea-glyoxal (MUG) resin is developed in the publication No. CN114196161A, and the problem that the resin has insufficient toughness after solidification and the like is solved, so that the shock resistance of the modified wood is reduced. Thus, there is a need to modify MUG resins, such as adding polymer segments or crosslinking monomers, to alleviate their brittleness to some extent. The organosilicon compound has good stability and heat resistance, and is easy to rotate in molecular chains and has good flexibility, so that the organosilicon compound is introduced into the MUG resin, the toughness, stability, heat resistance and other performances of the MUG resin can be improved, and the comprehensive performance of the wood impregnated with the organosilicon modified MUG resin is further improved. The invention is different from other organic silicide modified urea-formaldehyde resin, phenolic resin and polyacrylate emulsion resin, in the preparation process of the resin, mainly organic silicide is introduced into resin molecules, the molecular weight distribution range of the synthesized polymer is larger, the synthesized polymer is used for gluing wood and improving the bonding strength of the wood, but the invention is a wood modifier for synthesizing low molecular weight resin, and the wood modifier can be immersed into wood cells through external acting force to realize wood modification, so the control of the synthesis process of the organic silicide modified MUG resin is the key for preparing the wood modified resin. At present, no report exists on the synthesis of the organosilicon modified MUG resin, so the invention designs a novel wood modifier, and the boosting solid wood is applied to green and environment-friendly modification. Disclosure of Invention The invention aims to provide a preparation method of an organosilicon modified formaldehyde-free amino resin, and aims to solve the problem of insufficient toughness of the formaldehyde-free amino resin after curing in the prior art. The invention is realized in such a way that the preparation method of the organic silicon modified formaldehyde-free amino resin comprises the following preparation steps: 1) Adding glyoxal into a reaction kettle, regulating the pH value of the glyoxal to 4.0-6.0 by utilizing a pH regulator, adding melamine, uniformly stirring the glyoxal and the melamine, heating to 40-50 ℃ and reacting for 30-60 min; 2) Adding primary urea and a dispersing agent into the reaction kettle, heating to 50-70 ℃ and reacting for 30-60 min; 3) Adding urea, organic silicide and deionized water for the second time into the reaction kettle, and reacting for 1-3 hours; 4) And adding a flame retardant into the reaction kettle, stirring for 30min, regulating the pH value to 7.0-9.0 by using a pH regulator, and cooling and discharging to obtain the organosilicon modified formaldehyde-free amino resin. Further, according to the mass percentage of the components, the organic silicon modified formaldehyde-free amino resin comprises 20% -35% of glyoxal, 5% -20% of melamine, 10% -40% of urea, 5% -20% of organic silicide, 2% -10% of dispersing agent and 1% -5% of flame retardant, and the urea comprises first urea and second urea. Further, in the preparing step 3), the organic silicide includes one or more of methyl sodium silicate, hydroxyl-terminated polydimethylsiloxane, vinyltriethoxysilane and vinyltrimethoxysilane. Further, in the preparing step 2), the dispersing agent includes one or more of polyvinyl alcohol, polyethylene glycol, ethylene glycol, glycerol, isopropanol, pentaerythritol, ethanol and methanol. Further, in the preparation step 1) and the preparation step 4), the pH adjuster is one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium silicate