SU384845A1 - METHOD OF OBTAINING URETHANE ELASTOMERS - Google Patents

Description

I

This invention relates to methods for the flooring of urethane elastomers.

A known method for producing urethane elastoj Ito .B by reacting the isocyanate with polyesters, followed by introducing into the resulting fornomer a suspension of a crosslinking agent, diamine in an organic liquid, for example in castor oil, and heating. However, the lifetime of the reaction mixture is not long enough (a good 40 min).

In order to increase the viability of the reaction mixture, it has been proposed to use a surfactant as an organic liquid, such as hydroxyethyl octylphenol.

The proposed method consists in that the B prepolymer obtained by reacting the polyester with x: 1. iisocyanate is injected with diamine suspension, naimer 3,3-dichloro-4, 4-diaminodiphenylmethane, in the Novost-active substance, for example in ethoxylated octylphenol, with a weight ratio of diamine and surfactant fluid ranging from 2: 1 to 1: 1.

A significant increase in the life time (over 1 hour) is achieved by the fact that diamine crystals are coated with a protective film of a surfactant that prevents the copolymer of the prepolymer and

diamine and slows down the reaction between MiM. After molding, the temperature of the liquid polymer is raised above the melting point of the diamine; the protective spitting of the surfactant is destroyed and the elastomer quickly hardens. The resulting elastomer has good physical-mechanical and properties.

Example 1. In peaKtop load polyethylene adipate and 2,4-tolui LeNDiisocyanate and a weight ratio of 1: 0.15 and stir the mixture for 1 hour at 90 ° C. Into the resulting prepolymer, lead was added 0.08 wt. including the crosslinking agent, 3,3-dichloro-4,4-diaminodifineNilmethane, and after stirring, a life time of 15 minutes is determined. To determine the physicomechanical parameters, the polymer is poured into a mold and thermostatic for 20 hours.

Example 2. A suspension of 3,3 dichloro-4, 4-diamino 11phenyl methane was introduced into the prepolymer prepared by the method of example 1 (0.09

weight. h) in the top of the ST-actin substance - hydroxyethylamine octylphenol (0.08 wt. h.).

At the end of the experiment, a life time of 70 minutes is determined.

The physicomechanical characteristics of the resulting elastomer are shown in the table, where for comparison are given the corresponding indicators and elastomers obtained without the use of 3

yi surfactant or using castor oil.

384845

a significant increase in the life time and high physicomechanical properties, which makes it possible to use them for the production of large-sized molded products.

Thus, the inventive method allows to obtain urethane polymers with the inventive symbol.

A method of producing urethai elastomers by reacting isocyanate with polyesters, followed by introducing diamine suspension in an organic liquid into the obtained prepolymer and heating, characterized in that, in order to increase the viability of the reaction mixture, a surfactant is used as the organic liquid.