RU2232782C1 - 1,3-bis-[2-n-n-methoxybenzylideneamino)ethyl]adamantane as rubber vulcanization antiaging agent - Google Patents

Abstract

FIELD: rubber industry.

SUBSTANCE: invention proposes use of 1,3-bis-[2-N-n-methoxybenzylideneamino)ethyl]adamantane more clearly depicted by structural formula

as rubber vulcanization antiaging agent.

EFFECT: increased heat resistance of vulcanization products.

2 tbl, 2 ex

Description

The invention relates to a chemical compound, namely to 1,3-bis- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane, which can be used as an antioxidant for rubber vulcanization.

The inventive compound is described in the catalog “Enamine Products Listing”, Order No. TO 503-3673, CAS Registry No. 328110-05-0 ”," Tricyclo [3.3.1.13,7] decane-1,3-diethanamine, N, N'- bis [(4-methoxyphenyl) methylene] - ", 15 Nov. 2001.

Known dimer crotonylidene-α-naphthylamine (amine) of the formula

as an antioxidant for rubbers (AS No. 696012, MKI C 07 C 119/00, C 08 K 5/29, 1979).

However, the amine is not effective enough, since crotonic aldehyde is used in its preparation, which is prone to polymerization under synthesis conditions at a temperature of 140 ° C, and the use of a large amount (up to 10%) of oxalic acid or benzenesulfonic acid as a catalyst leads to contamination of the product. In addition, when it is used as an antioxidant for rubbers, an additional introduction of protective wax into the rubber mixture (Ceserin-80) is required.

The crotonilidene-α-naphthylamine dimer gives low heat resistance indicators of vulcanizates.

It is also known to use Nn-methoxyphenyl-m-phenoxyphenylmethanimine as antioxidants in the vulcanization of rubbers (RF patent No. 2117001, MKI C 07 C 251/24, C 08 K 5/29, 1998), No-hydroxy-phenyl-m-phenoxyphenylmethanimine (patent RF No. 2117000, MKI C 07 C 251/24, C 08 K 5/29, 1998), N-phenyl-m-phenoxyphenylmethanimine (RF patent No. 2116999, MKI C 07 C 251/24, C 08 K 5/29, 1998). However, when using these substances, a sufficiently effective heat resistance of the vulcanizates is not provided.

The closest in structure and purpose is N, N'-n-isopropylphenyl-n-phenylenediamine (diafen FP) (Handbook of rubber worker. - M .: Chemistry, 1971. - 608 s). However, when using this substance as an antioxidant, vulcanized rubbers have a low resistance to thermal aging, which leads to irreversible changes in their valuable technical properties.

The objective of the invention is to obtain a new antioxidant, which, when introduced into the rubber mixture, provides rubber products that are resistant to thermal aging.

The technical result when using the proposed compound is to increase the heat resistance of vulcanizates.

The technical result is achieved by using a new compound 1,3-bs- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane of the formula

Our 1,3-bis- [2- (N-n-methoxybenzylideneamino) -ethyl] adamantane (diimine) is prepared by the reaction of 1,3-diaminoethyladamantane with aromatic aldehyde-n-methoxybenzaldehyde.

The presence of two systems of conjugated bonds, as well as the presence of two mobile hydrogen atoms in the diimine molecule, increases the likelihood of their interaction with the active oxygen-containing radical of an oxidized rubber hydrocarbon, which are formed during prolonged exposure to temperature and repeated deformations, which increases the likelihood of an oxidation chain breaking and, thus, reduces the rate of oxidation of rubber, i.e. increases heat resistance of vulcanizates. The introduction of an n-methoxy group into the benzene ring increases the antioxidant resistance to water leaching, and also increases the endurance during repeated deformations.

1,3-bis- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane

1,3-Bis- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane is obtained by the classical condensation reaction of aldehydes with amines. 1,3-Diaminoethyladamantane is reacted with n-methoxybenzaldehyde in the presence of a solvent - ethyl alcohol - at a temperature of 40-60 ° C for 1.5-2 hours

The product precipitated after cooling is filtered off. There is no sewage and waste in production. Diimin is a crystalline substance of white color, soluble in chloroform, acetone, benzene. The product is practically non-toxic.

The invention is illustrated by the following examples.

Example 1. In a four-necked reactor equipped with a stirrer, thermometer and reflux condenser, 18.4 g (0.135 mol) of n-methoxybenzaldehyde and 15.0 g (0.0675 mol) of 1,3-diaminoethylamantane in 50 ml of ethyl alcohol are charged. The reaction mass is maintained at a temperature of 40-60 ° C for 1.5-2 hours. The crystalline product precipitated upon cooling is filtered off. The yield of diimine is 97%. T. pl. 146-147 ° C. Found,%: C 79.11, H 7.88, N 6.35. Calculated,%: C 78.60, H 8.29, N 6.11. IR spectrum, ν, cm ^-1 : 1576, 1532 (Ar), 1648 (CH = N), 1312.1108, 960 (Ad). ¹ H NMR (DMSO), δ, ppm: 6.95-7.68 m (8 H; Ar), 8.23 s (1H, -CH = N), 1.96 t (2H, Ad -CH ₂ ), 3.50 t (2H, -CH ₂ -N), 3.79 s (3H, CH ₃ O-), 1.45 m (14H, Ad).

Example 2. 1,3-Bis- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane is tested in standard rubbers, the composition of which is shown in Table 1. Diimine is administered instead of AF diaphen in an amount of 2 parts by mass per 100 parts by mass of rubber. Rubber is tested for resistance to aging and wear at a temperature of 100 ° C (GOST 9024-74, GOST 270-75, GOST 9026-74). The test results are presented in table. 2.

As follows from the data presented, 1,3-bis- [2- (N-n-methoxybenzylideneamino) ethyl] adamantane (diimine) is an effective anti-aging agent superior to diafen AF.

The conditional tensile strength after aging in air at 100 ° C for 24 hours changed by 83.3%, and the elongation after aging in air under the same conditions improved by 24.2%. Hardness after aging increased by 28.6%. The remaining indicators remained at the prototype level.

Thus, the above information indicates the fulfillment of the following set of conditions when using the claimed invention:

- a tool embodying the claimed invention, when used, is intended to be used as an antioxidant for vulcanization of rubbers;

- for the claimed invention in the form described in the claims, the possibility of its implementation using the means and methods described in the application and known prior to the priority date is confirmed;

- a tool embodying the claimed invention, in its implementation is able to ensure the achievement of a technical result.

Therefore, the claimed invention meets the requirement of "industrial applicability".

Claims (1)

The use of 1,3-bis- [2- (N-p-methoxybenzylideneamino) ethyl] adamantane of the general formula

as an antioxidant for rubber vulcanization.