Preparation process of urea-formaldehyde resin adhesive

A urea-formaldehyde resin and adhesive technology, which is applied in adhesives, aldehyde/ketone condensation polymer adhesives, adhesive types, etc., can solve problems such as heat cannot be recycled, complicated process, and high energy consumption, so as to improve the competitive advantage , simple process and reduced production cost

Inactive Publication Date: 2007-07-18
水煤浆气化及煤化工国家工程研究中心
View PDF0 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The final process of urea production is to spray and granulate the molten urea-urea solution. During the granulation process, the urea solution falls from more than 100°C to close to room temperature at the top of the prilling tower, and the heat contained in the urea solution cannot be recycled.
In addition, the process is complicated, the energy consumption is large, and the cost is high

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] (1). Add 420Kg of formaldehyde into the reaction kettle, and adjust the pH value to 9.0 with sodium hydroxide solution;

[0020] (2). Open the urea liquid valve, slowly add the first batch of 185Kg of liquid urea liquid transported by the urea synthesis device into the reactor, and when the reaction temperature is 95°C, keep it warm for 0.5 hours, and then adjust the pH with ammonium chloride solution =5.5, continue to react until the solution becomes turbid, and the viscosity is 15CP;

[0021] (3). Use sodium hydroxide solution to adjust pH=7.6, then add the second batch of liquid urea solution 10Kg delivered by the urea synthesis device;

[0022] (4). Dehydration under reduced pressure, control the temperature at 50°C, when the absolute pressure is 0.19 atmospheric pressure, and the viscosity is 5CP, finally add 10Kg of the third batch of liquid urea liquid transported by the urea synthesis device, and add 3kg of melamine;

[0023] (5). Adjust the pH to 8.5 with alka...

Embodiment 2

[0025] (1). Add 600Kg of formaldehyde into the reaction kettle, and adjust the pH value to 7.0 with sodium hydroxide solution;

[0026] (2). Open the urea liquid valve, slowly add 395Kg of the first batch of liquid urea liquid transported by the urea synthesis device into the reactor, and when the reaction temperature is 90°C after the addition, keep it warm for 1.5 hours, and then adjust it with ammonium chloride solution PH=4.0, continue to react until the solution becomes cloudy and the viscosity is 20CP;

[0027] (3). Use sodium hydroxide solution to adjust pH=7.0, then add the second batch of liquid urea solution 15Kg delivered by the urea synthesis device;

[0028] (4).Dehydration under reduced pressure, control the temperature at 70°C, when the absolute pressure is 0.08 atmospheric pressure, and the viscosity is 500CP, finally add 5Kg of the third batch of liquid urea solution transported by the urea synthesis device, and add 30kg of melamine;

[0029] (5). Use alkali ...

Embodiment 3

[0031] (1). Add 500Kg of formaldehyde into the reaction kettle, and adjust the pH value to 8.0 with sodium hydroxide solution;

[0032] (2). Open the urea liquid valve, slowly add 280Kg of the first batch of liquid urea liquid transported by the urea synthesis device into the reactor, and when the reaction temperature is 92°C after the addition, keep it warm for 1 hour, and then adjust the pH with ammonium chloride solution =4.5, continue to react until the solution becomes turbid, and the viscosity is 18CP;

[0033] (3). Use sodium hydroxide solution to adjust pH=7.3, then add the second batch of liquid urea solution 12Kg delivered by the urea synthesis device;

[0034] (4). Dehydration under reduced pressure, when the temperature is controlled at 60°C, the absolute pressure is 0.13 atmospheric pressure, and the viscosity is 250CP, finally add 8Kg of the third batch of liquid urea liquid transported by the urea synthesis device, and add 15kg of melamine;

[0035] (5). Adjust...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The present invention is process of preparing urea-formaldehyde resin adhesive. The preparation process includes the following steps: 1. adding formaldehyde in 420-600 weight portions into a reaction kettle and regulating pH value to 7.0-9.0 with alkali; 2. adding liquid urea from a urea synthesizing apparatus in 185-395 weight portions into the reaction kettle, reaction at 90-95 deg.c for 0.5-1.5 hr, regulating pH value to 4.0-5.5 with acid and further reaction until the solution becomes turbid and has viscosity of 15-20 CP; 3. regulating pH value to 7.0-7.6 with alkali and adding liquid urea of other 10-15 weight portions; 4. decompression dewatering, adding liquid urea of other 5-10 weight portions and modifier of 3-30 weight portions at temperature not higher than 70 deg.c and absolute pressure of 0.08-0.19 atm; and 5. regulating pH value to 7.5-8.5 with alkali, cooling to below 50 deg.c, discharging and packing.

Description

Technical field: [0001] The invention relates to an adhesive, in particular to a preparation method of a urea-formaldehyde resin adhesive. Background technique: [0002] Urea-formaldehyde resin glue is an adhesive with high bonding strength, water resistance, heat resistance and low cost. It is widely used in wood processing industry, paper products and other materials. Due to the use of urea-formaldehyde resin or the use of products prepared by urea-formaldehyde resin adhesives, the released formaldehyde stimulates people's eyes and respiratory system, seriously pollutes the environment, and endangers people's health. Standards have been formulated one after another, and relevant technical experts have done a lot of discussions and proposed many technical solutions. [0003] At present, the preparation process of urea-formaldehyde resin generally uses urea and formaldehyde as raw materials, and steam heating and temperature control are required in the preparation process o...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C09J161/24
Inventor 褚宏春吕运江吴章孔凡玲
Owner 水煤浆气化及煤化工国家工程研究中心
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap