Production method for dialdehyde starch adhesive

Abstract

The invention discloses a production method for a dialdehyde starch adhesive. The method comprises the following steps of: (1) dispersing alkali lignin: uniformly stirring 100 kilograms of dialdehyde starch and 800 kilograms of water, adding into a reaction kettle, adjusting the pH value to 9-9.5 by using alkaline water, adding 50 kilograms of alkali lignin and 5 kilograms of urea for the first time while stirring, heating to 40 DEG C, and reacting for 20 minutes; (2) forming hydroxymethyl and undergoing a condensation polymerization reaction: continually heating to 60 DEG C after the step (1), adding 50 kilograms of phenol and 5 kilograms of urea for the second time, heating to 90 DEG C, preserving heat, and reacting for 30 minutes; and (3) undergoing a starch complexing reaction: cooling and reacting simultaneously, cooling to 75 DEG C, adding 1.5 kilograms of sodium borate, cooling and reacting simultaneously while stirring, cooling to 45 DEG C, and discharging. The adhesive is mainly used for bonding bamboo and wood materials, and has the advantages of no free formaldehyde, high bonding speed, high initial viscosity, high water tolerance and high corrosion resistance.

Description

technical field [0001] The invention relates to a production method of an organic adhesive, in particular to a production method of a modified dialdehyde starch adhesive with dialdehyde starch, urea, phenol and alkali lignin as main raw materials. Background technique [0002] Phenolic resin adhesive has the advantages of high bonding strength, moisture resistance, heat resistance and chemical corrosion resistance, and is an adhesive for industrial production of plywood, fiberboard and particleboard. The raw materials phenol and formaldehyde are toxic compounds dependent on petroleum. The tension of petroleum will inevitably increase the production cost of phenolic resin adhesives; in addition, phenolic resin will release formaldehyde during preparation and use, which is harmful to health and damages the environment. This prompts people to actively look for suitable substitutes for phenol and formaldehyde. The sugarcane waste residue produced in the sugar production process ...

AI Technical Summary

Problems solved by technology

CN1309141A discloses "a modified phenolic resin and its production method". The release amount of free phenol and free aldehyde after modification is not ideal, which affects environmental protection; March 2009 "Journal of Hunan University of Arts and Science (Natural Science Edition)" No. The first issue of volume 21 published the article "Research on Bagasse Lignin Modified Phenolic Resin Adhesive" by Mr. Lin Mingsui, which introduced a modification method. The glue also has a high content of free formaldehyde