Environment-friendly formaldehyde-free urea resin and preparation method thereof

Abstract

The invention relates to an environment-friendly formaldehyde-free urea resin and a preparation method thereof. The environment-friendly formaldehyde-free urea resin is characterized by being prepared from the following components in parts by weight: 300 parts of urea, 135 parts of dialdehyde starch, 0.5-1 part of formic acid, 25-30 parts of sodium hydroxide liquid, 405 parts of water, 1.2 parts of borax and 0.5-1 part of tributyl phosphate. The prepared environment-friendly formaldehyde-free urea resin (or called as a urea-dialdehyde starch glue) contains functional groups such as an aldehyde group, an acylamino group and a hydroxymethyl group, and is high in bonding strength and appropriate in pH value; the environment-friendly formaldehyde-free urea resin is an impurity-free yellowish uniform liquid, and is high in solid content, zero in free formaldehyde (environment-friendly), and capable of meeting the requirements on a glue for treating waterproof abrasive paper, an abrasive cloth, abrasive paper for wood and an abrasive belt.

Description

Technical field [0001] The invention relates to a formaldehyde-free urea-formaldehyde resin for coating abrasive tools and a preparation method thereof. Background technique [0002] Urea-formaldehyde resin is cheap, simple to manufacture and has excellent performance. It is widely used in the cloth-based treatment of water-resistant sandpaper, wood sand, emery cloth and abrasive belts in coated abrasive tools. However, urea-formaldehyde resin releases formaldehyde during its production and use, which has a very negative impact on human health and environmental protection. The addition reaction for preparing urea-formaldehyde resin is a reversible reaction, so the free formaldehyde in the glue can only be reduced to a certain limit and cannot be eradicated. Therefore, the present invention uses dialdehyde starch instead of formaldehyde as the aldehyde-containing material to react with urea to develop a urea dialdehyde starch adhesive (environmentally friendly formaldehyde-f...

AI Technical Summary

Problems solved by technology

However, urea-formaldehyde resin will release formaldehyde during production and use, which will have very adverse effects on human health and environmental protection.

The addition reaction to prepare urea-formaldehyde resin is a reversible reaction, so the free formaldehyde in the glue can only be reduced to a certain limit, and it is impossible to eradicate it.

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