Preparation method of dampproof E1 glue used for producing wood-based panels

Abstract

The invention relates to a preparation method of dampproof E1 glue used for producing wood-based panels. The preparation method comprises the following processing steps: firstly taking formaldehyde with concentration of 48% and adding an alkali to regulate the pH value to 8.2-8.5; then after uniform stirring, adding melamine and the first batch of urea, ensuring the pH value of a solution to be more than 7.0, adding acid to regulate the pH value of the solution to 5.3, then adding the alkali to regulate the pH value of the solution to 6.5, adding urea for the second time, adding the alkali to regulate the pH value of the solution to 8.5, adding urea for the third time when the temperature is reduced to 70 DEG C after uniform stirring, simultaneously adding an aid HL-1, carrying out stirring and heat insulation for more than 30 minutes and adding the alkali to regulate the pH value of the solution to 8.0; and finally finishing heat insulation, reducing the temperature to 35 DEG C, adding the alkali to regulate the pH value of the solution to 8.5-9.5 and then releasing glue, thus preparing the dampproof E1 glue product used for producing wood-based panels. The preparation method has positive effect that the environmental friendliness of glue is ensured by adding urea in batches according to the ratio of urea.

Description

technical field [0001] The invention belongs to the technical field of environment-friendly polymer new materials, and relates to a method for preparing moisture-proof E1 grade glue used for producing wood-based panels. Background technique [0002] Since January 1, 2002, my country has implemented the mandatory standard of "limitation of formaldehyde release in wood-based panels and their products for interior decoration and decoration materials", which puts forward new requirements for the amount of formaldehyde released from wood-based panels. [0003] At present, in the world, according to the level of formaldehyde emission, it is divided into three levels: E2, E1, and E0, that is, E2≤30mg / 100g, E1≤9mg / 100g, E0≤3mg / 100g, and E1 level means that every 100g sample contains The amount of formaldehyde is less than or equal to 9mg, which is generally measured by the drilling method. [0004] The production of moisture-proof grade E1 high-standard panels requires very high te...

AI Technical Summary

Problems solved by technology

Although a few large domestic enterprises have similar products, most of them use low-concentration formaldehyde dehydration process to make glue, resulting in a large amount of waste water discharge