JPS6320216B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the following general formula (In the formula, R is hydrogen or a methyl group, A is -CH
=N-,

[expression] or

The present invention relates to novel diphenylamine derivatives represented by the following formulas and rubber-like polymer deterioration inhibitors containing these as active ingredients. In general, rubbery polymeric substances, especially substances with unsaturated bonds in their molecular chains, are exposed to ozone,
When exposed to the effects of oxygen, light, heat, etc., they undergo deterioration such as softening or hardening, resulting in significant deterioration of various properties, which often poses practical problems. In order to prevent such deterioration, it has been conventional practice to add various deterioration inhibitors such as phenols and amines to synthetic resins or rubber, and they are quite effective under relatively moderate temperature conditions. is demonstrated. However, in recent years, the conditions for using rubber products have become even more severe, and improvements in engines, as seen in automobile exhaust gas countermeasures, have resulted in temperatures around the engine becoming higher than before. By applying this method, it has become extremely difficult to provide rubber products that can withstand practical use. The inventors of the present invention have conducted extensive research to find a compound that has an even better anti-deterioration effect on rubbery polymers, and as a result of the present invention, they have discovered a novel and excellent diphenylamine derivative. That is, an object of the present invention is to provide a diphenylamine derivative which is a novel anti-deterioration agent having an excellent effect of preventing the deterioration of rubber-like polymers. Novel diphenylamine derivatives of the present invention (In the formula, R is hydrogen or a methyl group, A is -C=
N-,

[expression] or

Each of the groups represented by [Formula]] can be easily obtained by a conventional organic synthesis method. That is, the starting material p-aminodiphenylamine or the p-phenylenediamine derivative having R ₁ and R ₂ as substituents, and acrolein or methacrolein (where A is -C=
N- group), halomethylstyrene, or halomethyl-α-methylstyrene (where A is

[Formula] group); The starting material p-hydroxydiphenylamine or the p-hydroxydiphenylamine derivative with the above R ₁ and R ₂ as substituents and halomethylstyrene or halomethyl-α-methylstyrene ( The above A is

Specifically, by reacting the starting material with a suitable solvent such as methanol, ethanol, benzene,
The target substance of the present invention can be easily recovered as a precipitate by dissolving it in toluene or the like and dropping an equivalent or excess amount of the substance into this solution while heating and stirring. The diphenylamine derivative of the present invention is extremely effective as a rubber-like polymer deterioration inhibitor for preventing the deterioration of rubber products used under harsh conditions (high temperature, oil, etc.). When using the diphenylamine derivative of the present invention as a rubber-like polymer deterioration inhibitor, it may be added to the rubber-like polymer, or it can be incorporated into the polymer as a polymerizable deterioration inhibitor at the stage of manufacturing the rubber-like polymer. It is used in a state where it is copolymerized with other monomers and directly bonded to the polymer molecular chain, but there are no particular restrictions on the manner in which it is used. When the diphenylamine derivative of the present invention is blended into a rubbery polymer as a deterioration inhibitor, the amount used is not particularly limited, but is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the rubbery polymer. Parts by weight. There are no particular restrictions on the rubber-like polymers that can be applied, but diene polymers that are susceptible to thermal deterioration,
For example, it exhibits remarkable effects when used with polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, polyisoprene, polychloroprene, etc., or modified polymers thereof by hydrogenation or the like. Furthermore, there are no particular restrictions on the method of blending the anti-degradation agent of the present invention, and it may be added and mixed into the latex or solution of the rubber-like polymer.For solid rubber, a commonly used mixer such as It may be added on mixing rolls or in an internal Banbury mixer or the like. In addition, when the diphenylamine derivative of the present invention is copolymerized with other monomers in a free radical polymerization system in order to directly bond it into the molecular chain of a rubbery polymer, the diphenylamine derivative contains 0.01 to 20 parts by weight in 100 parts by weight of the total monomers. It is used in parts by weight, preferably in the range of 0.1 to 10 parts by weight. The monomer copolymerized with the diphenylamine derivative of the present invention may be one or more conjugated diene monomers selected from 1,3-butadiene, isoprene, 1,3-pentadiene, chloroprene, etc. Good and
It may also be a mixture of these conjugated diene monomers and monoethylenically unsaturated monomers. Monoethylenically unsaturated monomers include unsaturated nitriles such as acrylonitrile, methacrylonitrile, and α-chloroacrylonitrile; monovinylidene aromatic hydrocarbons such as styrene, alkylstyrenes (o-, m-, or p-
unsaturated carboxylic acids or their esters, such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid or methyl acrylate, butyl acrylate, acrylic acid Examples include one or more of the following: 2-ethylhexyl methyl methacrylate and the like; unsaturated aldehydes such as acrolein and methacrolein; vinylpyridine; vinyl esters such as vinyl acetate and vinylidene halides such as vinylidene chloride and vinylidene bromide. Examples of free radical initiators that can be used in the practice of this invention are those known as "redox" initiators, such as ferrous sulfate, sodium formaldehyde sulfoxylate, and e.g. cumene hydroperoxide, paramenthane hydroperoxide. Suitable combinations of organic peroxides such as oxide and other initiators such as azobisisobutyronitrile, benzoyl peroxide, hydrogen persulfate, potassium persulfate may also be used depending on the particular polymerization system. can. The rubber-like polymer obtained by adding and blending the diphenylamine derivative obtained in the present invention or the rubber-like polymer obtained by copolymerizing the diphenylamine derivative can be used alone or as necessary with natural rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, acrylonitrile. -Mixed with rubber-like polymers such as butadiene rubber and chloroprene rubber, and further compounded with conventional compounding chemicals such as reinforcing agents, fillers, plasticizers, softeners, vulcanizing agents, stabilizers, anti-aging agents, etc., and then molded. The final product is then vulcanized. Similarly, the rubbery polymer to which the diphenylamine derivative of the present invention is added or the rubbery polymer copolymerized with the diphenylamine derivative can be widely used in the form of unvulcanized rubber or latex.
In this case, in particular, the following mercaptobenzimidazoles are used as other deterioration inhibitors.

[Formula] or

[Formula] (wherein R ₃ is hydrogen, chlorine, bromine, or a C _{1 to} C ₁₂ hydrocarbon residue, M is a metal from Group 2 or 8 of the periodic table, and n is 2 or 3), for example 2-mercaptopenzimidazole or this Ni,
Zn salts, etc.; N-alkyl-substituted dithiocarbamic acids of the following formula (In the formula, R ₄ and R ₅ are hydrogen or C _{1 to 12} hydrocarbon residues, K is hydrogen or a metal of Group 1, Group 2, Group 4, Group 6 or Group 8 of the periodic table, m represents 1 to 4), for example, dibutyldithiocarbamic acid-
Ni, diethyldithiocarbamic acid-Zn, etc.; or dilaurylthiodipropionate, distearylthiodipropionate phenyl-(3-phenylthiopropionate), ethane-1,2-
bis(3-n-dodecylthiopropionate),
Ethane-1,2-bis(3-n-dodecylthio-
When used in combination with thioether compounds such as 2-methylpropionate), 3,6,9-trioxaundecene-1,11-bis(3-n-dodecylthiopropionate), the diphenylamine derivative of the present invention The deterioration prevention effect is synergistically improved. The anti-deterioration effect of the diphenylamine derivatives of the present invention is particularly applicable to fields where rubber products or rubber-like polymers containing these products are required to have a high degree of deterioration resistance for a long period of time, especially when they are in contact with solvents or oils, or are immersed in them.
For example, fuel hoses, printing rolls, spinning rolls, apron bands, packing, oil seals, diaphragms, fuel tanks, fiber coating agents,
It is particularly effective when used in areas such as adhesives. Next, the present invention will be specifically explained using examples. Synthesis example 1 p-aminodiphenylamine 36.8g (0.2mol)
and 2 g of acetic acid were added to 300 ml of methanol, and 10.2 g (0.2 mol) of methacrolein was added dropwise at 50° C. while stirring. After the completion of the dropwise addition, the precipitated product was stirred for 6 hours at 50°C or lower and washed with ether to give 4-anilino-N-(2-(2-methyl)propynylidene)aniline. 38.6g (yield 86%) was obtained. The melting point was 109°C. The results of elemental analysis were as follows. Actual value (%) C80.12, H7.27, N12.61 Theoretical value (%) C80.31, H7.20, N12.49 Synthesis example 2 p-aminodiphenylamine 36.8g (0.2 mol)
was added to 200 ml of toluene, and 16.8 g of sodium hydrogen carbonate and 30 ml of water were added to this, stirring for 60 ml.
30.5 g (0.2 mol) of p-chloromethylstyrene was added dropwise at ℃. After the dropwise addition was completed, the product was stirred for 4 hours at 60°C or below, and the precipitated product was separated and washed with water.
4-anilino-N-(4-vinylbenzyl)aniline 49.8g (yield 83%) was obtained. The melting point of this thing is
It was 143℃. The results of elemental analysis were as follows. Actual value (%) C83.78, H6.76, N9.46 Theoretical value (%) C83.95, H6.72, N9.33 Synthesis example 3 p-hydroxydiphenylamine 37.1g (0.2
mol) to 200 ml of toluene, add 16.8 g of sodium bicarbonate and 30 ml of water, and add 30.5 g of p-chloromethylstyrene at 60°C with stirring.
(0.2 mol) dropwise. After the completion of the dropwise addition, the precipitated product was stirred for 4 hours at 60°C or lower and washed with water to give 4-anilinophenyl 4-vinylbenzyl ether. 48.8g (yield 81%) was obtained. The melting point of this thing is
It was 139℃. The results of elemental analysis were as follows. Actual value (%) C83.51, H6.40, N4.82, O5.27 Theoretical value (%) C83.67, H6.37, N4.65, O5.31 Example 1 Synthesized in Synthesis Examples 1 to 3 The formulations shown in Table 1 were applied to a sample containing the diphenylamine derivative obtained above and a sample using N-phenyl-N'-isopropyl-p-phenylenediamine as a comparative example.
Heat aging and composite aging tests were conducted on the vulcanized samples obtained by press vulcanization at 160°C for 20 minutes. The results are shown in Table 2.

【table】

【table】

[Table] From the results in Table 2, it can be seen that the NBR containing the diphenylamine derivative of the present invention clearly has significantly improved heat aging resistance and combined aging resistance under extremely severe conditions. Example 2 A copolymer (NBR) of butadiene and acrylonitrile was prepared using the diphenylamine derivatives prepared in Synthesis Examples 1 to 3 as polymerizable monomers according to the polymerization recipe shown in Table 3. Raw materials other than butadiene are charged into a glass pressure-resistant bottle with an internal volume of about 1, and after repeated depressurization and nitrogen substitution to remove dissolved oxygen, butadiene is added and the bottle is sealed and sealed at 5°C.
Table 3 shows the final reaction rate and the Mooney viscosity of the crumb recovered from the latex by salting out. As a comparative example, after completion of polymerization, N,N'-diphenyl-p-phenylenediamine was added to a latex containing no diphenylamine derivative as a copolymerization component in an amount of 3 parts by weight based on 100 parts by weight of the rubber solid content. .

【table】

[Table] Example 3 The copolymer rubber (NBR) obtained in Example 2 was prepared as a vulcanizate sample using the same formulation and vulcanization conditions as in Example 1, and heat aging and composite aging tests were conducted. The results are shown in Table 4.

【table】

[Table] From the results shown in Table 4, NBR copolymerized with the diphenylamine derivative of the present invention clearly showed an excellent effect on heat aging resistance, and the combined aging resistance was significantly improved.

Claims (1)

[Claims] 1. The following general formula (In the formula, R is hydrogen or a methyl group, A is -CH
=N-, [Formula] or [Formula], respectively) A diphenylamine derivative represented by: 2 General formula below (In the formula, R is hydrogen or a methyl group, A is -CH
A rubber-like polymer deterioration inhibitor containing a diphenylamine derivative represented by the following formula: =N-, [Formula] or [Formula], respectively.