A two-phase accelerator and a method for preparing the same, an elastic rubber and a method for preparing the same

Abstract

The application discloses a two-phase accelerator and a preparation method thereof, and an elastic rubber and a preparation method thereof. The preparation method of the two-phase accelerator comprises the following steps: (1) trithiocyanuric acid is reacted with a strong base to generate a triazine metal salt compound; (2) the triazine metal salt compound is reacted with a zinc salt to generate a triazine zinc salt compound; (3) the triazine zinc salt compound is reacted with p-hydroxy bromobenzene to generate a triazine compound containing a phenolic hydroxyl group; and (4) the triazine compound containing the phenolic hydroxyl group is dehydrated and condensed with ethoxyquinoline to generate the two-phase accelerator. The two-phase accelerator DTTPA is synthesized by adopting a four-step method, can realize double chemical reactions on SBR and PVC at the same time, directly participates in the co-crosslinking of the rubber and the PVC, does not need to generate an intermediate and then participate in crosslinking, and solves the blending problem of the rubber and the PVC.

Description

Technical Field

[0001] This invention belongs to the field of rubber materials, and particularly relates to a two-phase accelerator and its preparation method, and a rubber and its preparation method. Background Technology

[0002] As domestic and international wind turbine manufacturers produce megawatt-class models with increasingly larger power outputs and more compact nacelle spaces, the constraints on the layout of elastic supports are also increasing. This leads to increasingly severe fatigue loads on gearbox suspension supports, with the average stress value of gearbox suspension supports under fatigue loads rising from the original 10MPa to 20MPa, and some products reaching 30MPa. Improving the load-bearing capacity of rubber is therefore urgently needed.

[0003] Improving the load-bearing capacity of rubber requires enhancing its modulus. The modulus of rubber is affected by factors such as rubber content, filler type, and vulcanization system. This patent will improve the rubber modulus in the following two ways: 1. By using rubber-plastic blending and adding polyvinyl chloride (PVC); 2. By using large-particle-size carbon black and increasing the carbon black content.

[0004] One of the key challenges this patent addresses is the method of blending rubber and polyvinyl chloride (PVC). The blending of rubber and PVC requires a highly efficient co-crosslinking system that allows both the rubber and PVC phases to spontaneously and synchronously crosslink, as well as crosslinking between the two phases. It has been reported that 2,4-dithiol-6-dibutylaminotriazine (DB), when combined with the accelerator benzothiazole disulfide (DM), can effectively co-crosslink rubber and PVC. The crosslinking mechanism involves DB and DM first reacting to form a DB-DM intermediate, then the thiol groups (SH) in DB-DM react with the chlorine on the PVC, and the disulfide bonds react with the carbon chains in the rubber. Because the vulcanization crosslinking process in the rubber-plastic blend system is very complex, the process of DB and DM reacting to form the intermediate is highly accidental; more often, DB and DM react separately with PVC and rubber.

[0005] Therefore, there is a need for an accelerator that can stably crosslink rubber and polyvinyl chloride, enabling efficient blending of rubber and polyvinyl chloride and solving the problem of instability of DB and DM intermediates. Summary of the Invention

[0006] The technical problem to be solved by the present invention is the lack of a method for blending rubber and polyvinyl chloride to improve the load-bearing capacity of rubber while improving its fatigue resistance, thereby overcoming the deficiencies and defects mentioned in the background art above, and providing a two-phase accelerator and its preparation method, and an elastic rubber and its preparation method.

[0007] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0008] A two-phase promoter, the chemical structural formula of which is shown below.

[0009]

[0010] This patent designs and synthesizes a two-phase triazine accelerator that can directly participate in the co-crosslinking of rubber and PVC without the need to first generate an intermediate before participating in the crosslinking. Simultaneously, considering the need to improve the fatigue resistance of rubber while enhancing its load-bearing capacity, the synthesized triazine accelerator incorporates a fatigue-resistant antioxidant, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline (AW), through a chemical condensation method using a small intermediate molecule.

[0011] The two-phase promoter is designated as DTTPA.

[0012] Under the same technical concept, the present invention also provides a method for preparing a two-phase promoter, comprising the following steps:

[0013] (1) Trithiocyanate reacts with a strong base to produce a triazine metal salt compound;

[0014] (2) Triazine metal salts react with zinc salts to form triazine zinc salts;

[0015] (3) Triazine zinc salt compounds react with p-hydroxybromobenzene to generate triazine compounds containing phenolic hydroxyl groups;

[0016] (4) Triazine compounds containing phenolic hydroxyl groups undergo dehydration condensation with ethoxyquinoline to form a two-phase promoter.

[0017] Preferably, the specific operation method of step (1) is as follows: in the reaction vessel, trithiocyanate and strong base are added, wherein the molar ratio of trithiocyanate and strong base is 1:0.9-1; the reaction is carried out under an inert atmosphere for 6-12 hours; the solvent is evaporated and the triazine metal salt compound is obtained by vacuum drying.

[0018] Preferably, the strong base is NaOH and / or KOH.

[0019] Preferably, the specific operation method of step (2) is as follows: in a reaction vessel, a triazine metal salt compound, a zinc salt and a carbonate are added, wherein the molar ratio of the triazine metal salt compound, the zinc salt and the carbonate is 2.0-2.1:1:2.0-4.0; the reaction is carried out under an inert atmosphere for 6-12 hours; impurities are removed by filtration, the filtrate is evaporated and dried under vacuum to obtain the triazine zinc salt compound.

[0020] Preferably, the zinc salt is at least one of ZnSO4, ZnCl2, and Zn(NO3)2.

[0021] Preferably, the specific operation method of step (3) is as follows: in a reaction vessel, a triazine zinc salt compound, p-hydroxybromobenzene and carbonate are added, wherein the molar ratio of the triazine zinc salt compound, p-hydroxybromobenzene and carbonate is 1:1.0-1.2:2.0-4.0; more preferably, the carbonate is Na2CO3; under an inert atmosphere, the reaction is carried out at 50-60℃ for 12-24h; the mixture is filtered to remove impurities, the filtrate is evaporated to dryness, and the mixture is vacuum dried to obtain a triazine compound containing phenolic hydroxyl groups.

[0022] Preferably, the solvent in the reactions of steps (1), (2), and (3) is ethanol, the molar ratio of trithiocyanate to ethanol is 1:20-40, the molar ratio of triazine metal salt compound to ethanol is 2.0-2.1:60-90, and the molar ratio of triazine zinc salt compound to ethanol is 1:20-30.

[0023] Preferably, the specific operation method of step (4) is as follows: In a reaction vessel, a mixed solution of water and ethanol is prepared, with a volume ratio of water to ethanol of (7-9):1. Hydrochloric acid is added to adjust the pH to 2-4. Ethoxyquinoline and a triazine compound containing phenolic hydroxyl groups are added sequentially, with a molar ratio of ethoxyquinoline to triazine compound containing phenolic hydroxyl groups of 1.0-1.2:1.0. The reaction is carried out under an inert atmosphere at 80-100℃ for 24-36 hours with stirring. The two-phase promoter is obtained by vacuum distillation and vacuum drying.

[0024] Under the same technical concept, the present invention also provides an elastic rubber, characterized in that it is prepared from the following raw materials in parts by weight:

[0025] Raw rubber: 70-90 parts;

[0026] Polyvinyl chloride: 10-30 parts;

[0027] Reinforcing filler: 50-100 parts;

[0028] Plasticizer: 10-15 parts;

[0029] Anti-aging agent: 4-8 parts;

[0030] Surfactant: 3-5 parts;

[0031] Vulcanization accelerator: 3-6 parts;

[0032] The vulcanization accelerator includes a two-phase accelerator.

[0033] Preferably, the raw rubber comprises nitrile rubber (NBR). NBR is a copolymer of butadiene and acrylonitrile, therefore the NBR molecular chain structure contains cyano groups, which greatly enhances the polarity of NBR. PVC is also a polar polymer. According to the principle of like dissolves like, NBR and PVC have good compatibility.

[0034] Preferably, the reinforcing filler includes carbon black and white bleach, and the carbon black is selected with a coarse particle size. Using large-particle-size carbon black increases the carbon black content.

[0035] Preferably, the plasticizer includes a polar plasticizer; the antioxidant includes p-phenylenediamine antioxidants and microcrystalline wax; the activator includes one or both of stearic acid and barium oxide; and the vulcanization accelerator includes one or more of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide, and biphasic triazine accelerators.

[0036] Under the same technical concept, the present invention also provides a method for preparing elastic rubber, characterized by comprising the following steps:

[0037] At a temperature of 150-160℃, raw rubber and polyvinyl chloride are mixed evenly, and reinforcing filler, antioxidant and plasticizer are added in sequence and mixed for 5-8 minutes. After the material is fully absorbed, the temperature is lowered to below 100℃, and activator and accelerator are added in sequence and mixed for 3-5 minutes. After cooling for 12-24 hours, the elastic rubber is obtained by vulcanization.

[0038] Preferably, the vulcanization is carried out at a pressure of 18-24 MPa and a temperature of 170°C for 10 minutes.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0040] (1) The two-phase accelerator DTTPA of the present invention is synthesized in a 4-step method, which can achieve simultaneous dual chemical reactions on SBR and PVC, and directly participate in the co-crosslinking of rubber and PVC without the need to first generate intermediates and then participate in crosslinking, thus solving the problem of blending rubber and PVC.

[0041] (2) The elastic rubber of the present invention uses a two-phase accelerator DTTPA to connect the raw rubber and PVC, which increases the modulus of the rubber compound by 50% and the flexural properties by 50%.

[0042] (3) The method and mixing process for preparing the two-phase accelerator and rubber material of the present invention are simple, the equipment is highly versatile, the cost is low and the performance is stable. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is the DTTPA structural formula of Embodiment 1 of the present invention;

[0045] Figure 2 This is a schematic diagram of the DTTPA synthesis route in Example 1 of the present invention;

[0046] Figure 3 The reaction equation for step (1) of Example 1 of this invention, which is the synthesis of a triazine metal salt compound;

[0047] Figure 4 The reaction equation for the synthesis of the triazine zinc salt compound in step (2) of Example 1 of this invention;

[0048] Figure 5 The reaction equation for step (3) of Example 1 of this invention, which is the synthesis of a triazine compound containing a phenolic hydroxyl group;

[0049] Figure 6 The reaction equation for the synthesis of DTTPA in Example 1 of this invention is shown below;

[0050] Figure 7 This is a diagram illustrating the vulcanization crosslinking reaction mechanism of DTTPA, NBR, and PVC in Example 1 of the present invention. Detailed Implementation

[0051] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0052] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0053] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0054] Example 1:

[0055] like Figure 2 DTTPA synthesis route diagram, four-step synthesis of DTTPA, DTTPA structural formula as follows Figure 1 As shown.

[0056] (1) In a reaction vessel, add TCY (0.2 mol, 35.4 g), NaOH (0.2 mol, 8 g), and ethanol solvent (4 mol, 232 mL). Under a nitrogen atmosphere, react at room temperature for 8 h. After the reaction is complete, evaporate the solvent by rotary evaporation and dry under vacuum to obtain TCY-Na. The chemical reaction equation is as follows: Figure 3 As shown.

[0057] (2) In a reaction vessel, add TCY-Na (0.1 mol, 19.9 g), ZnCl2 (0.05 mol, 6.8 g), Na2CO3 (0.1 mol, 10.6 g), and ethanol solvent (3 mol, 170 mL). Under a nitrogen atmosphere, react at room temperature for 10 h. After the reaction is complete, filter to remove impurities, evaporate the filtrate to dryness under vacuum to obtain (TCY)2-Zn. The chemical reaction equation is as follows: Figure 4 As shown.

[0058] (3) In a reaction vessel, add (TCY)2-Zn (0.05 mol, 20.6 mol), p-hydroxybromobenzene (0.06 mol, 10.4 g), Na2CO3 (0.1 mol, 10.6 g), and ethanol solvent (1 mol, 58 mL). Under a nitrogen atmosphere, react at 60 °C for 24 h. After the reaction is complete, filter to remove impurities, evaporate the filtrate to dryness under vacuum to obtain (TCY)2-Zn-PH. The chemical reaction equation is as follows: Figure 5 As shown.

[0059] (4) In a reaction vessel, prepare 100 mL of a mixed solution of water and ethanol (volume ratio of water to ethanol: 9:1). Adjust the pH to 3 with hydrochloric acid. Then, add AW (0.06 mol, 16.5 g) and (TCY)2-Zn-PH (0.05 mol, 25.7 g) sequentially. Under a nitrogen atmosphere, stir at high speed for 24 h at 100 °C. After the reaction is complete, remove the solvent by vacuum distillation and dry under vacuum to obtain DTTPA. The chemical reaction equation is as follows: Figure 6 As shown.

[0060] The rubber compound was prepared according to the formulation in Example 1 of Table 1. The specific operation was as follows: NBR and PVC were mixed evenly in an internal mixer at 150°C. Then, carbon black N550, white bleach, antioxidant 6PPD, microcrystalline wax, and plasticizer DOS were added sequentially and mixed for 5-8 minutes. After complete material intake, the temperature was lowered to below 100°C. Then, activators (barium oxide and stearic acid) and vulcanization accelerators (sulfur, CBS, DB, or DTTPA) were added sequentially and mixed for 3-5 minutes. The mixture was then sheeted and cooled for 12-24 hours.

[0061] The vulcanized rubber of Example 1 was prepared.

[0062] The mechanism of vulcanization crosslinking reaction between DTTPA and NBR / PVC is as follows: Figure 7 As shown.

[0063] Table 1 Raw material ratio

[0064]

[0065]

[0066] Those skilled in the art often use parts to express the material ratio of rubber. The applicant has specified the mass of the raw materials used in this embodiment and comparative example in parentheses.

[0067] Comparative Example 1:

[0068] The rubber compound was prepared according to the formulation of Comparative Example 1 in Table 1, and Comparative Example 1 vulcanized rubber was obtained.

[0069] The rubber compounds prepared in Example 1 and Comparative Example 1 were vulcanized at 170°C for 10 minutes, and the properties of the resulting vulcanized rubbers are shown in Table 2. As can be seen from the test results in Table 2, compared with the comparative example, the strain compression modulus of the rubber material used in the high-load wind power elastic support element of this invention is increased by 51%, and the flexural performance is improved by 50%.

[0070] Table 2 Test Performance of Vulcanized Rubber

[0071]

[0072] In addition to the above embodiments, the present invention also includes other embodiments. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of the present invention.

Claims

1. A two-phase accelerator, characterized in that, The chemical structural formula of the two-phase promoter is shown below. 。 2. A method for preparing the two-phase promoter as described in claim 1, characterized in that, Includes the following steps: (1) Trithiocyanate reacts with a strong base to form a triazine metal salt compound; (2) Triazine metal salts react with zinc salts to form triazine zinc salts; (3) Triazine zinc salt compounds react with p-hydroxybromobenzene to generate triazine compounds containing phenolic hydroxyl groups; (4) Triazine compounds containing phenolic hydroxyl groups undergo dehydration condensation with ethoxyquinoline to form a two-phase promoter.

3. The method for preparing the two-phase promoter as described in claim 2, characterized in that, The specific operation method of step (1) is as follows: add trithiocyanic acid and a strong base to the reaction vessel, wherein the molar ratio of trithiocyanic acid and the strong base is 1:0.9-1; react under an inert atmosphere for 6-12 h; evaporate the solvent and dry under vacuum to obtain the triazine metal salt compound.

4. The method for preparing the two-phase promoter as described in claim 3, characterized in that, The strong base is NaOH or KOH.

5. The method for preparing the two-phase promoter as described in claim 2, characterized in that, The specific operation method of step (2) is as follows: add triazine metal salt compound, zinc salt and carbonate to the reaction vessel, wherein the molar ratio of triazine metal salt compound, zinc salt and carbonate is 2.0-2.1:1:2.0-4.0; react under an inert atmosphere for 6-12 h; filter to remove impurities, evaporate the filtrate to dry, and vacuum dry to obtain triazine zinc salt compound.

6. The method for preparing the two-phase promoter as described in claim 5, characterized in that, The zinc salt is at least one of ZnSO4, ZnCl2, and Zn(NO3)2, and the carbonate is Na2CO3.

7. The method for preparing the two-phase promoter as described in claim 2, characterized in that, The specific operation method of step (3) is as follows: add triazine zinc salt compound, p-hydroxybromobenzene and carbonate to the reaction vessel, wherein the molar ratio of triazine zinc salt compound, p-hydroxybromobenzene and carbonate is 1:1.0-1.2:2.0-4.0; react at 50-60℃ for 12-24 h under an inert atmosphere; filter to remove impurities, evaporate the filtrate to dry, and vacuum dry to obtain triazine compound containing phenolic hydroxyl groups.

8. The method for preparing the two-phase promoter according to any one of claims 3-7, characterized in that, The solvent in steps (1), (2), and (3) is ethanol. The molar ratio of trithiocyanate to ethanol is 1:20-40; the molar ratio of triazine metal salt compound to ethanol is 2.0-2.1:60-90; and the molar ratio of triazine zinc salt compound to ethanol is 1:20-30.

9. The method for preparing the two-phase promoter as described in claim 3, characterized in that, The specific operation method of step (4) is as follows: In the reaction vessel, a mixed solution of water and ethanol is prepared, with a volume ratio of water to ethanol of (7-9):

1. Hydrochloric acid is added to adjust the pH to 2-4. Ethoxyquinoline and a triazine compound containing phenolic hydroxyl groups are added sequentially, with a molar ratio of ethoxyquinoline to triazine compound containing phenolic hydroxyl groups of 1.0-1.2:1.

0. The reaction is stirred at 80-100℃ for 24-36 h under an inert atmosphere. The two-phase promoter can be obtained by vacuum distillation and vacuum drying.

10. An elastic rubber, characterized in that, It is prepared from the following raw materials in parts by weight: Raw rubber: 70-90 parts; Polyvinyl chloride: 10-30 parts; Reinforcing filler: 50-100 parts; Plasticizer: 10-15 parts; Anti-aging agent: 4-8 parts; Surfactant: 3-5 parts; Vulcanization accelerator: 3-6 parts; The vulcanization accelerator includes the two-phase accelerator according to claim 1 or the two-phase accelerator prepared by any one of claims 2-9.

11. The elastic rubber as claimed in claim 10, characterized in that, The raw rubber includes nitrile rubber; the reinforcing filler includes carbon black and white bleach; the plasticizer includes polar plasticizer; the antioxidant includes p-phenylenediamine antioxidant and microcrystalline wax; and the activator includes one or two of stearic acid and barium oxide.

12. A method for preparing elastic rubber as described in claim 10 or 11, characterized in that, Includes the following steps: At a temperature of 150-160℃, raw rubber and polyvinyl chloride are mixed evenly, and reinforcing filler, antioxidant and plasticizer are added in sequence and mixed for 5-8 min. After the material is fully absorbed, the temperature is lowered to below 100℃, and activator and accelerator are added in sequence and mixed for 3-5 min. After cooling for 12-24 h, the elastic rubber is obtained by vulcanization.

13. The method for preparing elastic rubber according to claim 12, characterized in that, The vulcanization was carried out at 170°C for 10 min under a pressure of 18-24 MPa.

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