A kind of bio-based amino resin retanning agent and preparation method thereof

Abstract

The invention belongs to the technical field of tanning materials, and specifically discloses a bio-based amino resin retanning agent and a preparation method thereof. The bio-based amino resin retanning agent is synthesized from the following raw materials in parts by weight: 100 parts of bio-based aldehyde, 5-50 parts of amino compound, and 5-20 parts of solubilizer. The bio-based amino resin retanning agent provided by the present invention, because the bio-based aldehyde used basically does not contain free formaldehyde, can effectively solve the problem of continuous release of free formaldehyde caused by the existing amino resin retanning agent and retanned leather base after reacting with amino compounds. To meet the product quality problems, so that it meets the manufacturing requirements of ecological leather. The preparation method of the bio-based amino resin retanning agent provided by the present invention has good operation and friendliness because the bio-based aldehyde used is not volatile and non-irritating, and at the same time, the preparation method is simple, the conditions are mild, the operability is strong, and it is easy to popularize. sex and market competitiveness.

Description

technical field [0001] The invention relates to the technical field of tanning materials, in particular to a bio-based amino resin retanning agent and a preparation method thereof. Background technique [0002] The dyeing and finishing of leather is through the combination of retanning agent, fatliquoring agent, dyestuff and other chemicals in leather, endowing leather with good mechanical properties and sensory properties, and improving the use value of leather. The retanning process in dyeing and finishing has long been hailed as the "golden touch" of the tanning industry. It can endow crust leather with various styles and functional properties, and plays a very important role in the tanning process. Amino resin has good selective filling performance, can promote the combination of fatliquor, dye, etc. with leather, and improve its absorption rate, and is one of the most widely used products in the retanning process. Traditional amino resins are mainly heterochain polymer...

AI Technical Summary

Problems solved by technology

If the technical solutions provided by the above two invention patents are used to prepare bio-based amino resins, there will be the following two problems: 1) When bio-based aldehydes and amino compounds react under neutral and alkaline conditions, due to biological Aldehyde will undergo elimination reaction as shown in formula (1) and Cannizzaro reaction as shown in formula (2), resulting in structural transformation, the content of aldehyde group can be reduced by 99.7%, and the addition of amino compound is low, so it will make the final The molecular weight of the product is low, which makes it difficult to show good retanning filling performance; 2) When the bio-based aldehyde reacts with the amino compound under weak acidic conditions, although the aldehyde group can be retained and the two can undergo cross-linking and condensation reactions , to generate macromolecular polycondensation products. However, because the polycondensation products lack enough hydrophilic groups, the polycondensation products obtained under this condition are insoluble in water and further polycondensation reactions will occur during storage, which not only affects product stability. At the same time, due to its poor water solubility, it cannot fully penetrate into the interior of the leather, so it is difficult to play a good role in retanning and filling

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