Preparing method for modifying organophosphorus tanning agent through compound containing amidogen and carboxyl functional groups simultaneously

Abstract

The invention belongs to the field of leather chemicals, and particularly relates to a preparing method for modifying an organophosphorus tanning agent through a compound containing amidogen and carboxyl functional groups simultaneously. The method includes the following steps: 1 molar of organophosphorus tanning agent is added into a reaction vessel; 0.5 molar to 3 molars of compound containing the amidogen and carboxyl functional groups simultaneously is weighed to be dissolved with water, and the solution is slowly added into the reaction vessel; the reaction temperature is set to range from 35 DEG C to 50 DEG C, and a reaction is made; the pH is adjusted to range from about 4.0 to about 7.0, and the reaction is continuously carried out; and after the reaction is finished, the modified organophosphorus tanning agent is obtained. Compared with an unmodified organophosphorus tanning agent, the crack strength of retannage leather is improved by 20 N / mm to 30 N / mm, the bursting strength is improved by 50 N / mm to 70 N / mm, the cracking height is improved by 1.5 mm to 3 mm, and the bursting height is improved by 3 mm to 5 mm. The finished leather fullness is better; and compared with the unmodified organophosphorus tanning agent, and the thickness of the retannage leather is improved by 5% to 10%.

Description

(1) Technical field [0001] The invention belongs to the field of leather chemical industry, in particular to a preparation method for modifying an organic phosphorus tanning agent with a compound containing both amino and carboxyl functional groups. (2) Background technology [0002] Tanning is a process of qualitative change that converts raw hide into leather, and the chemical materials that can convert hide into leather are called tanning agents. The tanning agents that can be used in the leather production process include inorganic tanning agents and organic tanning agents. [0003] In recent years, organophosphorus has gradually attracted people's attention as a leather tanning agent. Organophosphorus tanning agents not only have strong cross-linking ability with collagen, but also can endow the finished leather with properties such as antiseptic, flame retardant and strong tear strength. However, since there are four hydroxymethyl groups around a phosphorus atom in th...

AI Technical Summary

Problems solved by technology

However, since there are four hydroxymethyl groups around a phosphorus atom in the molecular structure of organophosphorus tanning agents, these four hydroxymethyl groups cannot fully react with collagen, so the remaining hydroxymethyl groups will change and release formaldehyde, which may improve the leather. The content of free formaldehyde in

In addition, the grain surface of leather tanned with organophosphorus tanning agent alone is white, but relatively flat and thin, and the fullness is not enough