Compound, preparation method and application thereof, and rubber

Abstract

The invention relates to the field of rubber anti-aging agents, in particular to a compound, a preparation method and application thereof and rubber. The compound comprises a sulfur-containing structure M and one or more structures A1 as shown in a formula (1) or structures A2 as shown in a formula (2) connected to the sulfur-containing structure M and # imgabs 0 #, R1 is selected from H, C1-C6 alkyl groups, amino groups or # imgabs 1 #, R6 is selected from H or C1-C6 alkyl groups, R2 is selected from H or C1-C6 alkyl groups, R3 is selected from H or C1-C6 alkyl groups, R4 and R5 do not exist or are independently selected from # imgabs 2 #, and R6 is selected from H or C1-C6 alkyl groups. The sulfur-containing structure M is selected from residues of at least one of melamine, bis-[gamma-(triethoxy silicon) propyl]-tetrasulfide, bis-[3-(triethoxy silicon)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoyl thiopropyltriethoxy silane, and the sulfur-containing structure M is selected from residues of at least one of melamine, bis-[gamma-(triethoxy silicon) propyl]-tetrasulfide, bis-[3-(triethoxy silicon)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoyl thiopropyltriethoxy silane. The compound serving as a rubber anti-aging agent has medium and long-term protection performance of a traditional anti-aging agent and also has the characteristic of migration resistance.

Description

Technical Field

[0001] The invention relates to the field of rubber antioxidants, and in particular to a compound, a preparation method and application thereof, and rubber. Background Art

[0002] Rubber materials are widely used in production and life due to their advantages of light weight, good flexibility, good sealing, and shock absorption and buffering. However, the unsaturated bonds in rubber materials can easily cause rubber aging, thus affecting the long-term use of rubber materials.

[0003] Rubber antioxidants are mainly divided into amine antioxidants, phenolic antioxidants, heterocyclic antioxidants and other categories, among which amine antioxidants are mostly small molecule compounds, such as IPPD, 6PPD, etc. Literature reports that the small molecule antioxidant 6PPD in automobile tires is easy to migrate out and will be further ozonated to form highly toxic substances, which has caused a sharp decline in the salmon population to a large extent. However, due to the small molecular weight of existing small molecule antioxidants, they are easy to volatilize, easy to migrate, and have poor extraction resistance during processing and use, resulting in a reduction in the concentration of antioxidants in rubber products. The anti-aging protection of rubber is not utilized, and the volatilized antioxidants will also cause harm to the environment and human health.

[0004] In the prior art, rubber antioxidants are volatile, easy to migrate, poorly dispersed in rubber, and poorly resistant to extraction. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of the prior art that the rubber antioxidant is easy to volatilize, easy to migrate, has poor dispersibility in rubber and poor extraction resistance, and to provide a compound and its preparation method and application as well as rubber.

[0006] In order to achieve the above object, the present invention provides a compound in a first aspect, wherein the compound comprises: a sulfur-containing structure M and one or more structures A1 represented by formula (1) or structures A2 represented by formula (2) connected to the sulfur-containing structure M,

[0007]

[0008] Wherein, R1 is selected from H, C1-C6 alkyl, amino or wherein R6 is selected from H or C1-C6 alkyl, R2 is selected from H or C1-C6 alkyl, R3 is selected from H or C1-C6 alkyl, R4 and R5 are absent or are independently selected from

[0009] The sulfur-containing structure M is selected from at least one residue of melamine, bis-[γ-(triethoxysilyl)propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoylthiopropyltriethoxysilane.

[0010] The second aspect of the present invention provides a method for preparing a compound, which comprises the following steps:

[0011] (1) mixing compound a represented by formula (3) with an alkenyl epoxy compound to carry out a first reaction to obtain a first product;

[0012] (2) subjecting the first product and the sulfur-containing compound to a second reaction under the action of a catalyst to obtain the compound;

[0013]

[0014] The definitions of R1 and R2 are the same as those described in the first aspect.

[0015] The third aspect of the present invention provides a compound obtained by the preparation method.

[0016] The fourth aspect of the present invention provides a use of the compound as an antioxidant in rubber.

[0017] A fifth aspect of the present invention provides a rubber, wherein the rubber comprises raw rubber and the compound.

[0018] Through the above technical scheme, the present invention provides a compound used as an antioxidant in rubber. Since the compound contains a sulfur-containing structure M and introduces a structure A1 or A2, the obtained compound antioxidant has good thermal oxidation aging strength and excellent migration resistance. The aromatic antioxidant has better compatibility with the aromatic rubber, and can further reduce the amount of vulcanizing agent used during rubber refining. To a certain extent, it has the functions of both a vulcanizing agent and an antioxidant. The preparation method of the rubber antioxidant has the advantages of simple process and high product yield; in addition, the rubber antioxidant has good dispersibility in rubber. DETAILED DESCRIPTION

[0019] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0020] The first aspect of the present invention provides a compound, wherein the compound comprises: a sulfur-containing structure M and one or more structures A1 represented by formula (1) or structures A2 represented by formula (2) connected to the sulfur-containing structure M,

[0021]

[0022] Wherein, R1 is selected from H, C1-C6 alkyl, amino or wherein R6 is selected from H or C1-C6 alkyl, R2 is selected from H or C1-C6 alkyl, R3 is selected from H or C1-C6 alkyl, R4 and R5 are absent or are independently selected from

[0023] The sulfur-containing structure M is selected from at least one residue of melamine, bis-[γ-(triethoxysilyl)propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoylthiopropyltriethoxysilane.

[0024] In some specific embodiments of the present invention, the sulfur-containing structure M can be selected from

[0025] The sulfur-containing structure M is bonded to the O atom in the structure A1 via the Si atom in M, or the sulfur-containing structure M is bonded to the C atom in the structure A2 via the S atom in M.

[0026] In the present invention, the sulfur-containing structure includes but is not limited to the above-mentioned structure.

[0027] In the present invention, the compound has outstanding migration resistance as an antioxidant. Since the compound contains a sulfur-containing structure M and introduces structure A1 or A2, the obtained compound antioxidant has good thermal oxidation aging strength and excellent migration resistance. The antioxidant with aromatic groups has better compatibility with aromatic rubbers, and can further reduce the amount of vulcanizer used during rubber mixing, and has the functions of both vulcanizer and antioxidant to a certain extent.

[0028] In some specific embodiments of the present invention, R4 does not exist, which means that the carbon atoms at both ends of R4 in Structure A1 are directly connected, and R5 does not exist, which means that the carbon atoms at both ends of R5 in Structure A2 are directly connected.

[0029] In some specific embodiments of the present invention, when the sulfur-containing structure M contains a Si-O bond, the O atom in the structure A1 is bonded to the Si atom in the sulfur-containing structure M; or, when the sulfur-containing structure M contains an SH group, the C atom in the structure A2 is bonded to the S atom in the SH group.

[0030] In some embodiments of the present invention, R1 is selected from H, amino or R2 is selected from H, R3 is selected from H or methyl, R4 and R5 are absent or are independently selected from

[0031] In some specific embodiments of the present invention, the molar ratio of the sulfur-containing structure M to the structure A1 or structure A2 is 1:(1-6).

[0032] In some specific embodiments of the present invention, the compound can be selected from at least one of the following compounds:

[0033]

[0034]

[0035] In the present invention, the compound structure includes but is not limited to the above structure.

[0036] In the present invention, the composition and structure of the compound can be determined by NMR, IR, GPC, elemental analysis, etc., or by preparing and feeding.

[0037] The second aspect of the present invention provides a method for preparing a compound, which comprises the following steps:

[0038] (1) mixing compound a represented by formula (3) with an alkenyl epoxy compound to carry out a first reaction to obtain a first product;

[0039] (2) subjecting the first product and the sulfur-containing compound to a second reaction under the action of a catalyst to obtain the compound;

[0040]

[0041] The definitions of R1 and R2 are the same as those described in the first aspect.

[0042] In some specific embodiments of the present invention, the compound a is selected from one or more of aniline, p-phenylenediamine, 4-aminodiphenylamine (RT base), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), N,N'-di-sec-butyl-p-phenylenediamine (44PD), N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylenediamine (7PPD).

[0043] In some specific embodiments of the present invention, the alkenyl epoxy compound is selected from one or more of vinyl ethylene oxide, glycidyl methacrylate and allyl glycidyl ether.

[0044] In the present invention, the first product obtained in step (1) is used to provide structure A1 or structure A2 in the first aspect.

[0045] In some specific embodiments of the present invention, the sulfur-containing compound is selected from one or more of thiocyanuric acid, bis-[γ-(triethoxysilyl)propyl]-tetrasulfide (Si-69), bis-[3-(triethoxysilyl)-propyl]-disulfide (Si-75), mercaptoalkoxysilane (Si-747) and 3-octanoylthiopropyltriethoxysilane (Si-777). The sulfur-containing compound is used to provide the sulfur-containing structure M in the first aspect.

[0046] In some specific embodiments of the present invention, the catalyst is selected from salicylic acid and / or dibutyltin dilaurate.

[0047] In some specific embodiments of the present invention, when the sulfur-containing structure M contains a Si-O bond, such as Si-69, the compound a is selected from RT base, and the alkenyl epoxy compound is selected from glycidyl methacrylate. The reaction process is as follows:

[0048]

[0049] Among them, the hydroxyl group in the reaction product of the first step is not limited to reacting with the Si-O-C2H5 group at a specific position in the sulfur-containing compound, that is, it can react with the Si-O-C2H5 group at any position in the sulfur-containing compound.

[0050] When the sulfur-containing structure M contains an SH group, such as trithiocyanuric acid, the compound a is selected from RT base, and the alkenyl epoxy compound is selected from glycidyl methacrylate. The reaction process is as follows:

[0051]

[0052] The double-bonded carbon atoms in the reaction product of the first step are not limited to reacting with SH groups at specific positions in the sulfur-containing compound, that is, they can react with SH groups at any position in the sulfur-containing compound.

[0053] In some specific embodiments of the present invention, the second reaction is carried out under solvent conditions, wherein the solvent is selected from n-heptane, acetone, xylene, chloroform or tetrahydrofuran.

[0054] In some specific embodiments of the present invention, the first reaction temperature is 85-150° C., and the first reaction time is 1-10 h.

[0055] In some specific embodiments of the present invention, the second reaction temperature is 80-200° C., and the second reaction time is 3-15 h.

[0056] In some specific embodiments of the present invention, in step (1), the molar ratio of compound a, alkenyl epoxy compound and sulfur-containing compound is (0.01-0.5):(0.01-0.5):(0.01-0.1).

[0057] In some specific embodiments of the present invention, in step (2), the amount of the catalyst is 3-10 mL relative to 0.01-0.1 mol of the sulfur-containing compound.

[0058] In the present invention, the composition and structure of the compound can be determined by NMR, IR, GPC, elemental analysis, etc., or by preparing and feeding.

[0059] The third aspect of the present invention provides a compound obtained by the preparation method.

[0060] The fourth aspect of the present invention provides a use of the compound as an antioxidant in rubber.

[0061] A fifth aspect of the present invention provides a rubber, wherein the rubber comprises raw rubber and the compound.

[0062] In some specific embodiments of the present invention, the compound is added to the rubber in an amount of 2-3 wt % of the raw rubber.

[0063] In some specific embodiments of the present invention, the mobility of the compound in the rubber is 1-2.5%.

[0064] The present invention will be described in detail below through examples.

[0065] In the following examples and comparative examples, if no specific conditions are specified, the reaction is carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial channels. The composition and structure of the compounds prepared in the following examples are determined by preparing the feed (after the reaction of the example is completed, the feed is basically reacted completely).

[0066] Example 1

[0067] 0.1 mol of RT base was dissolved in acetone and mixed with 0.1 mol of vinyl ethylene oxide, and reacted at 95°C for 3 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-69 in n-heptane, and reacted at 160°C for 5 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain compound P1;

[0068] Among them, the sulfur-containing structure M comes from Si-69, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4;

[0069] The structure of compound P1 is shown as follows:

[0070]

[0071] Example 2

[0072] 0.1 mol of aniline was dissolved in acetone and mixed with 0.1 mol of glycidyl methacrylate, and reacted at 100°C for 5 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-69 in n-heptane, and reacted at 140°C for 7 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P2;

[0073] Among them, the sulfur-containing structure M comes from Si-69, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4;

[0074] The structure of compound P2 is shown as follows:

[0075]

[0076] Example 3

[0077] 0.1 mol of RT base was dissolved in acetone and mixed with 0.1 mol of allyl glycidyl ether, and reacted at 95°C for 3 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-69 in n-heptane, and reacted at 160°C for 5 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P3;

[0078] Among them, the sulfur-containing structure M comes from Si-69, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4;

[0079] The structure of compound P3 is shown as follows:

[0080]

[0081] Example 4

[0082] 0.1 mol of p-phenylenediamine was dissolved in acetone and mixed with 0.1 mol of glycidyl methacrylate, and reacted at 100°C for 5 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-69 in n-heptane, and reacted at 120°C for 10 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P4;

[0083] Among them, the sulfur-containing structure M comes from Si-69, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4;

[0084] The structure of compound P4 is shown as follows:

[0085]

[0086] Example 5

[0087] 0.1 mol of 6PPD was dissolved in acetone and mixed with 0.1 mol of glycidyl methacrylate, and reacted at 150°C for 8 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-75 in n-heptane, and reacted at 180°C for 15 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P5;

[0088] Among them, the sulfur-containing structure M comes from Si-75, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4;

[0089] The structure of compound P5 is shown as follows:

[0090]

[0091] Example 6

[0092] 0.1 mol of 6PPD was dissolved in acetone and mixed with 0.1 mol of allyl glycidyl ether, and reacted at 150°C for 6 h under nitrogen protection to obtain an intermediate product; the intermediate product was mixed with 0.028 mol of Si-75 in n-heptane, and reacted at 180°C for 15 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture was transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P6;

[0093] Among them, the sulfur-containing structure M comes from Si-75, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:4; the structure of compound P6 is shown as follows:

[0094]

[0095] Example 7

[0096] 0.1 mol of RT base is dissolved in acetone and mixed with 0.1 mol of glycidyl methacrylate, and reacted at 85-150° C. for 1-10 h under nitrogen protection; the obtained intermediate product is mixed with 0.036 mol of melamine in n-heptane, and reacted at 80-200° C. for 3-15 h under the action of 5 mL of dibutyltin dilaurate to obtain a reaction product mixture; the reaction product mixture is transferred to a rotary evaporator to remove the solvent and then cooled to room temperature to obtain P7;

[0097] The sulfur-containing structure M is derived from melamine, and the molar ratio of the sulfur-containing structure M to the structure A1 is 1:3; the structure of compound P7 is shown as follows:

[0098]

[0099] Test Case

[0100] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 45 parts by weight of carbon black N330, 1.5 parts by weight of accelerator, 2.5 parts by weight of insoluble sulfur and 2 parts by weight of compounds A1-A7 obtained in Examples 1-7 were mixed, kneaded and vulcanized to obtain vulcanized rubbers B1-B7. The standard dumbbell-shaped films were cut by a slicer and subjected to ozone aging test and migration resistance test respectively.

[0101] Comparative Test Example 1: 100 parts by weight of styrene-butadiene rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 45 parts by weight of carbon black N660, 1.5 parts by weight of accelerator, 2.5 parts by weight of insoluble sulfur and 2 parts by weight of antioxidant IPPD were mixed, kneaded and vulcanized to obtain vulcanized rubber D1. Ozone aging test and migration resistance test were performed respectively.

[0102] Comparative Test Example 1: 100 parts by weight of styrene-butadiene rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 45 parts by weight of carbon black N660, 1.5 parts by weight of accelerator, 2.5 parts by weight of insoluble sulfur and 2 parts by weight of antioxidant 6PPD were mixed, kneaded and vulcanized to obtain vulcanized rubber D2. Ozone aging test and migration resistance test were performed respectively.

[0103] In the ozone aging experiment, the aging temperature was set at 100°C and the ozone amount was 100ppm. The test sample was aged for 1 day, and the retention rate of the tensile strength of the material after 3 days was taken as the anti-aging efficiency. Retention rate = parameter after aging / parameter before aging × 100%.

[0104] The migration resistance test includes water extraction resistance and migration test. For water extraction resistance, two pieces of film weighing about 5g were completely immersed in 100ml deionized water. After soaking at room temperature for 14 days, the water was evaporated and made into 10mL methanol solution. The antioxidant content in the solution was detected by high performance liquid chromatography. For the migration test, the film was contacted with a blank film without antioxidant at 1MPa pressure and 90℃ for 300min. Acetone was used as a solvent to extract the blank film and test the antioxidant content in acetone. The results are shown in Table 1.

[0105] Table 1

[0106]

[0107]

[0108] It can be seen from the results in Table 1 that the compound antioxidant obtained by Examples 1-7 of the present invention was used for performance testing. The tensile strength retention rate was high after ozone aging for 1 day and 3 days, and the water extraction rate and migration rate were only 1 / 10-1 / 5 of those in the comparative example. The antioxidant obtained by the technical solution of the present invention has good thermal oxygen aging strength and excellent migration resistance.

[0109] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A compound, characterized in that The compound comprises: a sulfur-containing structure M and one or more structures A1 represented by formula (1) or structures A2 represented by formula (2) connected to the sulfur-containing structure M, Wherein, R1 is selected from H, C1-C6 alkyl, amino or wherein R6 is selected from H or C1-C6 alkyl, R2 is selected from H or C1-C6 alkyl, R3 is selected from H or C1-C6 alkyl, R4 and R5 are absent or are independently selected from The sulfur-containing structure M is selected from at least one residue of melamine, bis-[γ-(triethoxysilyl)propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoylthiopropyltriethoxysilane.

2. The compound according to claim 1, characterized in that When the sulfur-containing structure M contains a Si—O bond, the O atom in the structure A1 is bonded to the Si atom in the sulfur-containing structure M; Alternatively, when the sulfur-containing structure M contains an SH group, the C atom in the structure A2 is bonded to the S atom in the SH group.

3. The compound according to claim 1 or 2, characterized in that R1 is selected from H, amino or R2 is selected from H, R3 is selected from H or methyl, R4 and R5 are absent or are independently selected from 4. The compound according to any one of claims 1 to 3, characterized in that The molar ratio of the sulfur-containing structure M to the structure A1 or structure A2 is 1:(1-6).

5. A method for preparing a compound, characterized in that: The steps include: (1) mixing compound a represented by formula (3) with an alkenyl epoxy compound to carry out a first reaction to obtain a first product; (2) subjecting the first product and the sulfur-containing compound to a second reaction under the action of a catalyst to obtain the compound; The definitions of R1 and R2 are the same as those in any one of claims 1 to 4.

6. The preparation method according to claim 5, characterized in that: The compound a is selected from one or more of aniline, p-phenylenediamine, 4-aminodiphenylamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylenediamine; Preferably, the alkenyl epoxy compound is selected from one or more of vinyl ethylene oxide, glycidyl methacrylate and allyl glycidyl ether; Preferably, the sulfur-containing compound is selected from one or more of melamine, bis-[γ-(triethoxysilyl)propyl]-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]-disulfide, mercaptoalkoxysilane and 3-octanoylthiopropyltriethoxysilane; Preferably, the catalyst is selected from salicylic acid and / or dibutyltin dilaurate.

7. The preparation method according to claim 5 or 6, characterized in that: The first reaction temperature is 85-150°C, and the first reaction time is 1-10h; Preferably, the second reaction temperature is 80-200°C, and the second reaction time is 3-15h; Preferably, in step (1), the molar ratio of compound a, alkenyl epoxy compound and sulfur-containing compound is (0.01-0.5): (0.01-0.5): (0.01-0.1); Preferably, in step (2), the amount of the catalyst is 3-10 mL relative to 0.01-0.1 mol of the sulfur-containing compound.

8. A compound obtained by the preparation method according to any one of claims 5 to 7.

9. Use of the compound according to any one of claims 1 to 4 and 8 as an antioxidant in rubber.

10. A rubber, characterized in that: The rubber comprises raw rubber and the compound according to any one of claims 1 to 4 and 8.

11. The rubber according to claim 10, characterized in that In the rubber, the compound is added in an amount of 2-3 wt% of the raw rubber; Preferably, the mobility of the compound in the rubber is 1-2.5%.

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