RU1789541C - Composition for preparing coatings - Google Patents

Abstract

Use: in any industry. SUMMARY OF THE INVENTION: in the coating composition, as a prepolymer, a compound of composition F 1 s-s-Esngs-x OCNR, HNOC-NN Lnj sn-sng-s - 1h soya n ... co contains an aromatic diamine-cured prepolymer forms coatings with increased strength and resistance to nitric acid (at 18-22 ° C for 1000 hours). 2 tab.

Description

ate with

The invention relates to compositions for the production of coatings, injection molded products and sealants and can be used in any industry where these products are used.

A known coating composition is comprised of a polybutadiene diol and toluene diisocyanate (TDI) liquid isocyanate terminated prepolymer, an amine hardener and an organic solvent.

The specified composition has high physical and mechanical characteristics, but coatings based on it are resistant to nitric acid only with a concentration of 5-10%.

Also known is a coating composition comprising a liquid prepolymer with terminal isocyanate

groups based on a copolymer of divinyl and piperylene with TDI. amine hardener and organic solvent.

However, this composition has the same drawback as the previous one.

The closest effect to be achieved is a coating composition comprising a liquid prepolymer with terminal isocyanate groups based on a divinyl-isoprene-TDI copolymer, an amine hardener and an organic solvent.

The coatings obtained on the basis of this composition are resistant to nitric acid with a concentration of 5-15%, however, they have very low physical and mechanical characteristics.

The purpose of the invention is to increase the strength and resistance to nitric acid of the resulting coatings.

vj 00 ABOUT

.N

This object is achieved in that in a composition comprising a liquid prepolymer with terminal isocyanate groups, an amine hardener and an organic solvent, a compound of the general formula is used as a prepolymer

-%, -

R "- R, -t-Ox F

I C-C-ESN, -C-X

OCNRjHNO C-N-N

CH3

, №, sn-sn, - s- i

 N-N-CONHRj-NCO

where X-N: -CHZ

n 10-50

R; RI - aliphatic monovalent radicals of a linear or branched structure Ci-C4

R2-C6Hi2 -; - C7H6 -: - Ci3Hio-, in the following ratio of components, wt.h .:

Specified Prepolymer 100

Aromatic Diamine 6-19. Organic Solvent 11-67

A liquid prepolymer is obtained by reacting the corresponding oligodiene rubber with hydrazone end groups with diisocyanate in a molar ratio of 1: 2, respectively, in an organic solvent medium at 0-20 ° C.

The passage of this reaction with the formation of a prepolymer of this structure is confirmed by IR spectroscopy: a decrease in the absorption intensity in the region 2240-2270, typical for NC 0-rpynn, the appearance of a band of 1310 stretching vibrations of C-0-C groups, and a redistribution of intensities in the region of carbonyl absorption , for which the groups of the initial acylhydrazone, as well as the formed carbamate group and the C M group included in the oxadiazoline cycle, are responsible for the disappearance of the 3200 NH band of the acylhydrazone group and the appearance of the 3300 cm NH band in a uniformly bonded carbamate group, as well as bands in the region 3410-3440, depending on the diisocyanate selected, relating to the NH free carbamate group.

The indicated limits of amine hardeners are determined by the content of isocyanate groups in the prepolymer. Change

these limits to a greater or lesser extent leads to a deterioration in the basic physical and mechanical properties and a decrease in the resistance to the effects of nitric acid of the resulting coatings.

The indicated limits of the organic solvent are determined by the technology for preparing the prepolymer with terminal isocyanate groups.

The composition of the invention may contain the desired additives, namely, catalysts, fillers in conventional amounts.

The use of said prepolymer with

no terminal isocyanate groups for coating were found in the literature, therefore, the invention meets the criterion of significant differences.

The following are examples illustrating the invention.

The composition is prepared immediately before use by mixing the prepolymer solution with the melt or solution.

aromatic diamine. To obtain coating samples, the composition prepared as described above is poured into molds with a release layer. The composition is cured at 18-22 ° C for 24 hours.

Example 1. The prepolymer is obtained by reacting 106.4 parts by weight of (1 mol) oligobutadiene dihydrazone dimethyl ketone with 33.6 parts by weight (2 mol) of hexamethylenediisocyanate (HMDI) in the medium of 15.4 parts by weight. butyl acetate. The reaction proceeds at 20 ° C for 30 minutes. As a result of the reaction, a liquid prepolymer with terminal isocyanate groups (, 0%) of the general formula

R

n CHj OCNRzHNOC-N-N iCHrC X

.RCH3

  1H3 n R

sn-sn2-s-sg I

Јn N-N-CONHRrNCO

where X-H: n 10; R, RI-CH3; Rz.-CeHu-.

The composition contains 100 parts by weight the specified prepolymer, 11 wt.h. butyl acetate - 55 ta, and 19 parts by weight 3,3-dichloro-4,4-diaminodiphenylmethane (Dia-X).

Example 2. The prepolymer receive

by reaction of 209.2 parts by weight (1 mol)

oligoisoprendigidrazona dipropylketone

from 34.8 m.h. (2 mol) TDI in a medium of 61 m.a. ethyl acetate. The reaction proceeds at 10 ° C for 20 minutes. As a result of the reaction, a liquid prepolymer with terminal isocyanate groups (N00 3.44%) of the general formula shown in Example 1 is obtained, where X is -CH3; n 25; R, Ri -C3H7; R2 is a CsNb.

The composition contains 100 m.h. the specified prepolymer, 25 m.h. ethyl acetate, 10.9 m.h. methyl ethyl ketone and 10.9 wt.h. Diameta-X.

Example 3. The prepolymer is prepared according to example 2. The composition contains 100 parts by weight of liquid prepolymer, the same as in example 2, 25 wt.h. ethyl acetate, 8 parts by weight dimethyl ketone and 8 parts by weight triethyl diaminobenzene.

Example 4. The prepolymer receive. Example 2. The composition contains 100 may, hours liquid prepolymer, the same as in example 2, May 25, h ethyl acetate, 7 parts by weight methyl ethyl ketone and 6 parts by weight 1,4-diamino-2-chlorobenzene,

Example 5, The prepolymer is prepared according to example 2. The composition contains 100 m.h. liquid prepolymer, the same as in example 2, 25 wt.h. ethyl acetate, 10 parts by weight dimethyl ketone and 7.3 parts by weight 1,4-diamino-2, b-dichlorobenzene.

Example 6. The prepolymer is obtained by reacting 239.7 parts by weight of (1 mol) oligobutadiene dihydrazone methyl ethyl ketone with 50 wt.h. (2 mol) diphenylmethanediisocyanate (DFMDI) in an environment of 115.9 parts by weight dioxane. The reaction proceeds within 25 minutes. The reaction yields a liquid prepolymer with terminal isocyanate groups (, 9%) of the general formula shown in Example 1, where X is H; p 40; R, RI -CH3 and -C2H5, respectively, R2 -C1zNu- .. -

The composition contains 100 parts by weight the specified prepolymer, 40 wt.h. dioxane, 9.2 parts by weight dimethylketone and 9.2 wt.h, Diameta-X.

Example 7. The prepolymer is obtained by reaction of 400 parts by weight of (1 mol) oligoisoprendihydrazone dibutylketone with 50 parts by weight (2 mol) DFMDI in the environment of 301.5

Claims (2)

SUMMARY OF THE INVENTION A coating composition comprising a liquid prepolymer with terminal isocyanate groups, an aromatic diamine and an organic solvent, characterized in that, in order to increase the strength and resistance to the effects of nitric acid coatings, in camas. butyl acetate. The reaction proceeds at 5 ° C for 20 minutes. As a result of the reaction, a liquid prepolymer with terminal isocyanate groups, 9%) of the general formula shown in Example 1, wherein X-CH3; n 50; R, Ri-C-iHg; R2-Ci3Hio-. The composition contains 100 parts by weight the specified prepolymer, 67 wt.h. butyl acetate and 6 parts by weight Diameta-X. Example 8 (control prototype). The composition contains 100 parts by weight liquid prepolymer with terminal isocyanate groups (, 1%) of the general formula OCN-R-NH-CO-0-CH2-CH CH-CHj - CHj-C CH-CHjj-jO-CO-NH-R-NCO o-u where n 57; m 5; R-CyHe-; 6.7 parts by weight methyl ethyl ketone and 6.7 parts by weight Diamete X The main physical and mechanical properties of the coatings obtained according to Examples 1-8 were determined after 14 days. after curing according to GOST 209-75. The test results are shown in table 1. In addition, the samples obtained according to examples 1-8 of the coatings were exposed to nitric acid at 18-22 ° C for 1000 h in accordance with GOST 9.30-74. The test results are given in table. 2. Thus, as follows from the test data, only when using the liquid prepolymer with terminal isocyanate groups of the specified formula in the coating composition, it is possible to obtain coatings that are 2-7 times physicomechanical and resistant to nitric acid is twice as high as similar coatings made from compositions where the product of the reaction of a divinyl-isoprene copolymer with toluene diisocyanate is used as a liquid prepolymer. as a prepolymer, it contains a compound of the general formula R, -tox g4 I, s-s- {sng's OCNR HNOC-N-N kcnz, hj ,, sh-enl-s-ss I CH N-N-C ° NHR2-NCO where XN: CH3: R, RI is a linear or branched aliphatic monovalent Ci-CU radical; R2 is C6H12 -., - C1gNu-; p-10-15, in the following ratio of components compositions, ma.h .: Specified prepolymer 100 Aromatic diamine 6-19 Organic solvent 11-67 Table 1 table 2