Preparation method of highly methyl etherified amino resin

Abstract

The invention discloses a preparation method of highly methyl etherified amino resin, and relates to a synthetic preparation method of a liquid coating cross-linking agent-amino resin. The method comprises the following steps of: putting methanol and hexamethylolmelamine in a reaction kettle, wherein the weight ratio of the methanol and hexamethylolmelamine is 1:1-10, adding acid to adjust pH value to acidity, raising temperature to 20-50 DEG C for the first time, maintaining the temperature for 15min to 2h, raising temperature to 50-80 DEG C for the second time, then maintaining the temperature for 15min to 2h, then adding alkali to neutralize, adjusting the pH value to 7-10, raising the temperature by steam, dealcoholizing at constant pressure, then depressurizing, further removing the low-boiling-point substances at a pressure lower than -0.09MPa to obtain the highly methyl etherified amino resin product. The invention solves the problem of complex manufacturing processes, combines the two steps into one step, is simple and convenient to operate and control with period of time shortened from original 18h / kettle to about 9h / kettle and enhances the yield obviously, lowers the cost, reduces the energy consumption by 2 / 3, reduces the content of free formaldehyde and improves the environmental performance.

Description

technical field [0001] The invention relates to a method for preparing a resin, in particular to a method for synthesizing and preparing a liquid paint crosslinking agent—amino resin. Background technique [0002] Amino resin (also known as melamine-formaldehyde resin) is a thermosetting polymer produced by the polycondensation reaction of melamine (commonly known as melamine) and 37% formaldehyde solution or paraformaldehyde. A good melamine formaldehyde resin should have a wide range of colors, excellent electrical insulation, flame retardancy, high temperature resistance (-40-110°C), pollution resistance, water resistance, safety and hygiene, and other superior properties. Therefore, highly methyl etherified amino Resin research plays a very important role in the development of amino resin crosslinking technology. [0003] At present, enterprises that generally produce highly methyl etherified amino resins use a two-step method to synthesize highly methyl etherified amin...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies existing in the prior art, propose a new synthesis technique of highly methyl etherified amino resin, use hexamethylolmelamine as a two-step reaction raw material, replace one-step methylolation reaction, aim at Solve the problems existing in the prior art such as complex process, high energy consumption, large amount of aldehyde-containing wastewater, strong odor, low production capacity, unstable quality, etc. The process is simple in operation, easy to control the conditions, and less in product quality fluctuations

The present invention improves its original complex process