CN111662482B

CN111662482B - Vulcanizing agent composition, composition for preparing rubber compound, rubber compound and preparation method thereof, and tire

Info

Publication number: CN111662482B
Application number: CN202010707830.3A
Authority: CN
Inventors: 王璨; 范汝良; 林向阳; 王文芳; 李红伟; 蒋小强; 张宁
Original assignee: Sino Legend China Chemical Co ltd; Red Avenue New Materials Group Co Ltd
Current assignee: Sino Legend China Chemical Co ltd; Red Avenue New Materials Group Co Ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2022-07-26
Anticipated expiration: 2040-07-21
Also published as: CN111662482A

Abstract

A vulcanizing agent composition, a composition for preparing rubber compound, the rubber compound, a preparation method thereof and a tire belong to the technical field of rubber modification. The vulcanizing agent composition comprises: any two or three of a modified maleimide, an arylphenol disulfide, and 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane. The vulcanizing agent composition can replace partial sulfur to form a novel compound cross-linking bond, and the compound cross-linking bond can weaken the hysteresis effect of a rubber compound obtained by vulcanizing the vulcanizing agent composition, namely the rubber compound obtained by vulcanizing the vulcanizing agent composition has more excellent dynamic performance, lower heat generation and better heat aging resistance.

Description

Vulcanizing agent composition, composition for preparing rubber compound, rubber compound and preparation method thereof, and tire

Technical Field

The application relates to the technical field of rubber modification, in particular to a vulcanizing agent composition, a composition for preparing rubber compound, the rubber compound, a preparation method of the rubber compound and a tire.

Background

The study of low hysteresis loss and low heat build-up in tires over long runs is one of the hot spots in many performance studies of current tire compounds. During the period of loading and high-speed running of the tire, the rubber compound inside the tire can generate dynamic heat to increase the temperature of the tire body, so that the rubber compound at different parts of the tire is subjected to different degrees of thermal aging. Such problems usually occur in the material structure, such as base rubber, shoulder pad rubber, bonding rubber, apex rubber, split rubber, etc. (hereinafter referred to as key part rubber), which further promote embrittlement or softening of the rubber material in the tire, leading to early failure phenomena such as chipping, shoulder vacancy or split bead blasting of the rubber material under the tire tread, and the shoulder vacancy may even lead to dangerous traffic accidents.

For rubber, it is important to study low hysteresis loss and low heat build formulations for tire compounds. The cyclic compression set of a tire during high speed driving requires a tire compound having low heat build up and good heat resistance.

Therefore, reducing heat generation under dynamic conditions and improving heat resistance have been the focus of attention in recent years, while ensuring the mechanical properties of tire compounds.

Disclosure of Invention

The application provides a vulcanizing agent composition, a composition for preparing a rubber compound, the rubber compound, a preparation method of the rubber compound and a tire, which can solve the technical problem that the interior of the existing tire rubber is easy to embrittle or soften.

The embodiment of the application is realized as follows:

in a first aspect, the present application provides a vulcanizing agent composition comprising: any two or three of modified maleimide, alkylphenol disulfide, and 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

In the technical scheme, the vulcanizing agent composition can replace part of sulfur to form a novel compound cross-linking bond, and the compound cross-linking bond can weaken the hysteresis effect of the rubber compound obtained by vulcanizing the vulcanizing agent composition, namely the rubber compound obtained by vulcanizing the vulcanizing agent composition has more excellent dynamic performance, lower heat generation and better heat aging resistance.

In a first possible example of the first aspect of the present application in combination with the first aspect, the vulcanizing agent composition includes, in parts by weight, 0.1 to 4 parts of the modified maleimide and 0.1 to 3 parts of the alkylphenol disulfide;

alternatively, the vulcanizing agent composition comprises 0.1 to 4 parts of modified maleimide and 0.1 to 3 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane;

optionally, the vulcanizing agent composition comprises 0.1 to 3.5 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane and 0.1 to 3.5 parts of alkylphenol disulfide;

optionally, the vulcanizing agent composition includes 0.1 to 3 parts of the modified maleimide, 0.1 to 2 parts of the alkylphenol disulfide, and 0.1 to 2 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

In combination with the first aspect, in a second possible example of the first aspect of the present application, the above-mentioned modified maleimide includes one or more of the following compounds:

wherein R comprises a straight chain alkyl, branched alkyl, or alkenyl group.

In the above examples, the modified maleimide in the vulcanizing agent composition may be one or more of the above compounds. When two or more than two compounds are selected as the modified maleimide in the vulcanizing agent composition, the rubber compound obtained by vulcanizing the vulcanizing agent composition has lower compression heat generation and better thermal aging resistance.

In a second aspect, the present application provides a composition for preparing a rubber compound, which comprises 100 parts by weight of rubber, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of an accelerator, 0.5-4 parts by weight of an activator, and 0.5-7 parts by weight of the vulcanizing agent composition.

In the technical scheme, the vulcanizing agent composition can be matched with sulfur to act together to crosslink rubber, so that a novel composite crosslinking bond is formed. On one hand, the amount of sulfur in the composition for preparing the rubber compound is reduced, and the part of the sulfur, which causes the reduction of the crosslinking density, is compensated by the vulcanizing agent composition, so that the rubber compound prepared from the composition for preparing the rubber compound still maintains higher crosslinking degree and higher strength; on the other hand, the amount of the sulfur is reduced, the polysulfide bond formed by the sulfur can be reduced, and the rubber compound obtained by adding the vulcanizing agent composition for vulcanization has more excellent dynamic performance, lower heat generation and better heat aging resistance.

In a first possible example of the second aspect of the present application in combination with the second aspect, the above activator comprises a fatty acid zinc salt and/or an aromatic carboxylic acid zinc salt.

Alternatively, the fatty acid zinc salt comprises zinc isooctanoate and the aromatic carboxylic acid zinc salt comprises zinc benzoate.

In the above example, the activator can promote the ring-opening fracture of sulfur, form more disulfide and monosulfide cross-links, and reduce the generation of polysulfide cross-links, thereby improving the stretching strength of the rubber compound, reducing the compression deformation of the rubber compound and reducing the heat generation of the rubber compound.

In combination with the second aspect, in a second possible example of the second aspect of the present application, the composition for preparing a rubber compound further includes a filler, and the filler includes, by weight, 1 to 90 parts of carbon black and/or 1 to 85 parts of white carbon black.

In a third possible example of the second aspect of the present application in combination with the second aspect, the composition for preparing a mix further includes 0.1 to 8.5 parts by weight of a silane coupling agent.

Alternatively, the silane coupling agent comprises any one or more of bis- [ (triethoxysilyl) propyl ] tetrasulfide, bis- [ (triethoxysilyl) propyl ] disulfide, and 3-octanoylthio-1-propyltriethoxysilane.

In a third aspect, the present application provides a method of preparing a mix, comprising: mixing 100 parts by weight of rubber, 1-175 parts by weight of filler, 0.1-8.5 parts by weight of silane coupling agent and 0.5-4 parts by weight of activator to prepare master batch, and mixing the master batch, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of accelerator and 0.5-7 parts by weight of the vulcanizing agent composition to prepare final rubber to prepare rubber compound.

In the technical scheme, the preparation method is simple and convenient, and the rubber compound with more excellent dynamic performance, lower heat generation and better heat aging resistance can be prepared.

In a fourth aspect, the present application provides a rubber composition prepared according to the method for preparing a rubber composition described above.

In the technical scheme, the rubber compound prepared by the method has the advantages of excellent dynamic performance, lower heat generation and better heat aging resistance.

In a fifth aspect, the present examples provide a tire made using the above-described rubber composition.

In the technical scheme, the tire prepared by adopting the rubber compound has low heat generation and high heat resistance, and the heat accumulation is obviously reduced under the same condition, so that the service life is longer.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a graph of a rheometer according to examples 1, 5 and 11 and comparative examples 1 to 2 in test example 1 of the present application;

FIG. 2 is a plot of tan delta versus strain for 90 ℃ vulcanizates of examples 1, 5, 11 and comparative examples 1-2 in Experimental example 2 herein;

FIG. 3 is a plot of tan delta at 5% strain versus temperature for the vulcanizates of examples 1, 5, 11 and comparative examples 1-2 in Experimental example 2 herein.

Detailed Description

Embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present application and should not be construed as limiting the scope of the present application. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The principle of the rubber for tires is to examine two main properties of durability and flexibility. Generally, tire base rubbers are made by vulcanizing rubber with more sulfur and a small amount of accelerators. The tire base rubber prepared by the method can form more polysulfide crosslinking bonds and less disulfide and monosulfide crosslinking bonds.

The inventors have found that polysulfide linkages undergo large deformations and are susceptible to failure during high speed travel. Over time, the temperatures experienced by the polysulfide crosslinks increase with increasing dynamic heat generation, and the polysulfide crosslinks rearrange to form more disulfide and monosulfide crosslinks, increasing the crosslink density, which in turn converts the tire compound from a flexible rubber to a brittle material. Leading to the susceptibility of the compound to failure, such as compound catalyzed chipping, and the like, the entire process is known as thermal aging.

The following detailed description is directed to a vulcanizing agent composition, a composition for preparing a rubber compound, a preparation method thereof, and a tire in the embodiments of the present application:

the present application provides a vulcanizing agent composition comprising: any two or three of modified maleimide, alkylphenol disulfide, and 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

The vulcanizing agent composition can replace partial sulfur to form a novel compound cross-linking bond, and the compound cross-linking bond can weaken the hysteresis effect of a rubber compound obtained by vulcanizing the vulcanizing agent composition, namely the rubber compound obtained by vulcanizing the vulcanizing agent composition has more excellent dynamic performance, lower heat generation and better heat aging resistance.

In one embodiment of the present application, the vulcanizing agent composition may include 0.1 to 4 parts by weight of the modified maleimide and 0.1 to 3 parts by weight of the alkylphenol disulfide, for example, the vulcanizing agent composition includes 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, or 4 parts of the modified maleimide and 0.1, 0.5, 1, 1.5, 2, 2.5, or 3 parts of the alkylphenol disulfide.

In other embodiments herein, the vulcanizing agent composition may further include 0.1 to 4 parts by weight of a modified maleimide and 0.1 to 3 parts by weight of 1, 6-bis (N, N '-dibenzylthiocarbamoyldithio) -hexane, for example, the vulcanizing agent composition includes 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5 or 4 parts of a modified maleimide and 0.1, 0.5, 1, 1.5, 2, 2.5 or 3 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

The sulfiding agent composition may also include 0.1 to 3.5 parts of 1, 6-bis (N, N '-dibenzylthiocarbamoyldithio) -hexane and 0.1 to 3.5 parts of an alkylphenol disulfide, for example, the sulfiding agent composition includes 0.1, 0.5, 1, 1.5, 2, 2.5, or 3 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane and 0.1, 0.5, 1, 1.5, 2, 2.5, or 3 parts of an alkylphenol disulfide.

The vulcanizing agent composition may further include 0.1 to 3 parts of modified maleimide, 0.1 to 2 parts of alkylphenol disulfide, and 0.1 to 2 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane. For example, the vulcanizing agent composition includes 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, or 4 parts of modified maleimide, 0.1, 0.5, 1, 1.5, 2, 2.5, or 3 parts of alkylphenol disulfide, and 0.1, 0.5, 1, 1.5, 2, 2.5, or 3 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

Wherein the modified maleimide comprises one or more of the following compounds:

wherein R comprises a straight chain alkyl, branched chain alkyl, cycloalkyl, heterocycloalkyl, substituted alkyl, substituted cycloalkyl, or alkenyl.

Optionally, R is selected from C ₁ -C ₃₀ Straight or branched chain alkyl, cycloalkyl, heterocycloalkyl, and C ₂ -C ₁₅ The alkenyl group of (1).

Alternatively, R is selected from C ₁ -C ₂₀ A straight or branched alkyl group of, and C ₂ -C ₁₀ The alkenyl group of (1).

That is, the modified maleimide can be selected from any one or two or three or four or five of the above compounds and mixed in any proportion.

When two or more than two compounds are selected as the modified maleimide in the vulcanizing agent composition, the rubber compound obtained by vulcanizing the vulcanizing agent composition has lower compression heat generation and better thermal aging resistance.

The chemical formula of the alkylphenol disulfide is as follows:

wherein R comprises an alkyl group;

alternatively, R is tert-butyl.

The chemical formula of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane is as follows:

the application also provides a composition for preparing the rubber compound, which comprises 100 parts of rubber, 1-5 parts of sulfur, 0.5-3 parts of an accelerator, 0.5-4 parts of an activator and 0.5-7 parts of the vulcanizing agent composition in parts by weight.

The vulcanizing agent composition can be matched with sulfur to act together to crosslink the rubber to form a novel composite crosslinking bond. On one hand, the amount of sulfur in the composition for preparing the rubber compound is reduced, and the part of the sulfur, which causes the reduction of the crosslinking density, is compensated by the vulcanizing agent composition, so that the rubber compound prepared from the composition for preparing the rubber compound still maintains higher crosslinking degree and higher strength; on the other hand, the amount of the sulfur is reduced, the polysulfide bond formed by the sulfur can be reduced, and the rubber compound obtained by adding the vulcanizing agent composition for vulcanization has more excellent dynamic performance, lower heat generation and better heat aging resistance.

In one embodiment of the present application, the composition used to prepare the rubber compound comprises, in parts by weight, 100 parts of rubber, 1.5 parts of sulfur, 0.7 parts of accelerator, 2 parts of activator, and 2 parts of the above-described vulcanizing agent composition. In one other embodiment herein, the composition used to prepare the rubber compound may further include 100 parts by weight of rubber, 1, 1.5, 2.5, 3, 3.5, 4, or 4.5 or 5 parts by weight of sulfur, 0.5, 1, 2, 2.5 or 3 parts by weight of an accelerator, 0.5, 1, 1.5, 2.5, 3, 3.5 or 4 parts by weight of an activator and 0.5, 1, 2, 3, 5, 6 or 7 parts by weight of the above-described vulcanizing agent composition.

The rubber may be natural rubber, as well as other rubbers commonly used in the manufacture of tires.

Accelerators are used to accelerate rubber vulcanization.

Optionally, the promoter comprises NS, CZ, DZ.

The activator can promote the ring opening and the fracture of the sulfur, form more disulfide and monosulfide cross-linking bonds and reduce the generation of polysulfide cross-linking bonds, thereby improving the stretching strength of the rubber compound, reducing the compression deformation of the rubber compound and reducing the heat generation of the rubber compound.

Optionally, the activator comprises a zinc salt of a fatty acid and/or a zinc salt of an aromatic carboxylic acid.

Wherein the fatty acid is a C8-10 linear chain/branched chain fatty acid.

In one embodiment of the present application, the activator may be zinc benzoate. In other embodiments of the present application, the activator may also be zinc isooctanoate, or zinc benzoate and zinc isooctanoate mixed in any ratio.

The composition for preparing the rubber compound also comprises a filler, wherein the filler comprises 1-90 parts by weight of carbon black and/or 1-85 parts by weight of white carbon black.

Wherein the particle size range of the carbon black is between 1 and 60 nm.

The carbon black with large particle size is used for replacing the carbon black with small particle size wholly or partially, the smaller the particle size of the carbon black is, the more difficult the mixing is, the material eating speed is slow, the energy consumption is high, the heat generation is high, and the more difficult the dispersion is. The large-particle-size carbon black is used for replacing the small-particle-size carbon black, so that the heat generation of the rubber material can be effectively reduced.

Optionally, the carbon black includes one or more of N110, N220, N326, N330, N375, N550, and N660.

In one embodiment of the present application, the carbon black may be N330. In some other embodiments herein, the carbon black may also be N220, N326, N110, N375, N550 or N660, or may be mixed N220 and N326, or may be mixed N326 and N330, or may be mixed N375 and N550, or may be mixed N220, N326 and N330, or may be mixed N375, N550 and N660, or may be mixed N220, N326, N330 and N375, or may be mixed N220, N326, N330, N375 and N550, or may be mixed N220, N326, N330, N375, N550 and N660.

The addition of the white carbon black reduces the interaction before filling and reduces the heat generation of the rubber material.

Optionally, the white carbon black is super-active precipitated white carbon black, and the specific surface area of the white carbon black is 150-200 m ² The volatile component is 4-7% at 105 ℃ for 2h, the pH value of a 5% aqueous solution is 5.4-7.0, and the conductivity of a 4% aqueous solution is less than 1300 mu s/cm.

The composition for preparing the rubber compound further comprises 0.1-8.5 parts by weight of a silane coupling agent.

The rubber can generate coupling reaction under the action of a silane coupling agent, and forms a composite vulcanization system together with the vulcanizing agent.

In one embodiment herein, the silane coupling agent may include bis- [ (triethoxysilyl) propyl ] tetrasulfide. In other embodiments of the present application, the silane coupling agent may further comprise bis- [ (triethoxysilyl) propyl ] disulfide or 3-octanoylthio-1-propyltriethoxysilane, or bis- [ (triethoxysilyl) propyl ] tetrasulfide and bis- [ (triethoxysilyl) propyl ] disulfide mixed in any ratio, or bis- [ (triethoxysilyl) propyl ] disulfide and 3-octanoylthio-1-propyltriethoxysilane mixed in any ratio, or bis- [ (triethoxysilyl) propyl ] tetrasulfide, bis- [ (triethoxysilyl) propyl ] disulfide and 3-octanoylthio-1-propyltriethoxysilane mixed in any ratio.

The compositions used to prepare the mixes herein also include some of the adjuvants common to mixes.

The auxiliary agent comprises, by weight, 1.0-4.0 parts of tackifying resin, 3.5-10.0 parts of zinc oxide, 0.5-2.0 parts of stearic acid, 1.0-3.5 parts of an anti-aging agent, 0-0.3 part of an anti-scorching agent CTP, 0-3.0 parts of a methylene donor, 0-2.5 parts of a low rolling resistance functional resin and the like.

The application also provides a preparation method of the rubber compound, which comprises the following steps: master batches and final batches.

The master batch comprises the steps of mixing and adding 100 parts by weight of rubber, 1-175 parts by weight of filler, 0.1-8.5 parts by weight of silane coupling agent and 0.5-4 parts by weight of activating agent into an internal mixer, starting to mix the rubber with the filling coefficient of 75-80%, wherein the rubber mixing time is 2-4 min, discharging the rubber at 150-160 ℃, and controlling the thickness of a rubber sheet to be 2-3 mm by a lower sheet of the internal mixer to prepare the master batch;

the internal mixer can be added with other auxiliary agents, including but not limited to 1-3 parts of carbon black dispersing agent, 1.0-4.0 parts of tackifying resin, 3.5-10.0 parts of zinc oxide, 0.5-2.0 parts of stearic acid, 1.0-3.5 parts of anti-aging agent, 0-0.3 part of anti-scorching agent CTP, 0-3.0 parts of methylene donor and 0-2.5 parts of low rolling resistance functional resin.

Optionally, the carbon black dispersant comprises a fatty acid zinc soap salt.

Optionally, the anti-aging agent comprises anti-aging agent 4020 and anti-aging agent RD.

In one embodiment of the application, the final rubber compound comprises the step of mixing the prepared master batch, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of accelerator and 0.5-7 parts by weight of the vulcanizing agent composition, adding the mixture into an open mill, and starting rubber mixing, wherein the rubber mixing time is 6-7 min, the open mill temperature is controlled to be 70-80 ℃, and the thickness of a rubber sheet is controlled to be 2-3 mm under the condition of a lower sheet of the open mill, so that the rubber compound is prepared.

In other embodiments of the application, the final rubber mixing comprises the step of mixing the prepared master batch, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of accelerator and 0.5-7 parts by weight of the vulcanizing agent composition, adding the mixture into an internal mixer for mixing for 1.5-2 min, and starting rubber discharge at 98-102 ℃, wherein the rubber sheet thickness of the lower sheet of the internal mixer is controlled to be 2-3 mm, thus obtaining the rubber mixture.

The application also provides a rubber compound prepared by the preparation method of the rubber compound.

The rubber compound prepared by the application has more excellent dynamic performance, lower heat generation and better heat aging resistance.

The application also provides a tire which is prepared by adopting the rubber compound.

The tire of the present application has low heat generation and high heat resistance, and heat accumulation becomes significantly less under the same conditions, thereby having a longer service life.

A vulcanizing agent composition, a composition for preparing a rubber compound, a method for preparing the rubber compound, and a tire according to the present application will be described in further detail with reference to examples.

Example 1

The embodiment of the application provides a vulcanizing agent composition, a composition for preparing a rubber compound, the rubber compound and a preparation method thereof, wherein the vulcanizing agent composition comprises the following components in parts by weight:

1. vulcanizing agent composition

The vulcanizing agent composition comprises 1 part by weight of modified maleimide, 0.5 part by weight of alkylphenol disulfide and 0.5 part by weight of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane, wherein the chemical formula of the modified maleimide is as follows:

2. composition for preparing rubber mixtures

The composition comprises 100 parts by weight of natural rubber, 33 parts by weight of carbon black of N330, 15 parts by weight of white carbon black, 1.5 parts by weight of bis- [ (triethoxysilyl) propyl ] tetrasulfide, 2 parts by weight of zinc benzoate, 2 parts by weight of soap salt of zinc fatty acid, 3.5 parts by weight of ZnO, 1 part by weight of stearic acid, 1.5 parts by weight of anti-aging agent 4020, 1 part by weight of anti-aging agent RD, 1.5 parts by weight of sulfur, 0.7 part by weight of accelerator NS, 0.2 part by weight of antiscorching agent CTP and the vulcanizing agent composition in the step 1;

wherein the particle size distribution of the carbon black is between 26 and 30 nm.

3. Rubber compound and preparation method thereof

Master batch: mixing and adding 100 parts by weight of natural rubber, 33 parts by weight of carbon black of N330, 15 parts by weight of white carbon black, 1.5 parts by weight of bis- [ (triethoxy silicon) propyl ] tetrasulfide, 2 parts by weight of zinc benzoate, 2 parts by weight of soap salt of fatty acid zinc, 3.5 parts by weight of ZnO, 1 part by weight of stearic acid, 1.5 parts by weight of antioxidant 4020 and 1 part by weight of antioxidant RD into an internal mixer, starting rubber mixing with a filling coefficient of 75-80% maintained, wherein the rubber mixing time is 3min, rubber discharging is carried out at 150-160 ℃, and the thickness of a rubber sheet is controlled to be 2-3 mm by a lower sheet of the internal mixer to prepare master rubber;

final mixing rubber: mixing and adding the master batch, 1.5 parts by weight of sulfur, 0.7 part by weight of accelerator NS, 0.2 part by weight of scorch retarder CTP and 1 vulcanizing agent composition (1 part by weight of modified maleimide, 0.5 part by weight of alkylphenol disulfide and 0.5 part by weight of 1, 6-bis (N, N' -dibenzyl thiocarbamoyldithio) -hexane) into an open mill for rubber mixing, wherein the rubber mixing time is 7min, the open mill temperature is controlled to be 70-80 ℃, and the film thickness of the lower sheet of the open mill is controlled to be 2-3 mm, thus obtaining the rubber compound.

Example 2

examples the vulcanizing agent composition was modified to 1 part by weight of a modified maleimide having the following chemical formula and 1 part by weight of an alkylphenol disulfide based on example 1:

the rest is the same as in example 1.

Example 3

examples the vulcanizing agent composition was changed to 1 part by weight of modified maleimide and 1 part by weight of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane based on example 1, wherein the chemical formula of the modified maleimide was as follows:

the rest is the same as in example 1.

Example 4

examples the vulcanizing agent composition was changed to 1 part by weight of alkylphenol disulfide and 1 part by weight of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane based on example 1. The rest is the same as in example 1.

Example 5

examples the vulcanizing agent composition was changed to 1 part by weight of modified maleimide, 0.5 part by weight of alkylphenol disulfide and 0.5 part by weight of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane based on example 1, wherein the chemical formula of the modified maleimide was as follows:

the molar ratio of the two modified maleimides is 1: 1.

The rest is the same as in example 1.

Example 6

examples the vulcanizing agent composition was changed on the basis of example 1 to 1 part by weight of modified maleimide, 0.5 part by weight of alkylphenol disulfide and 0.5 part by weight of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane, wherein the chemical formula of the modified maleimide was as follows:

the molar ratio of the two modified maleimides is 1: 1.

The rest is the same as in example 1.

Example 7

the molar ratio of the three modified maleimides is 1: 1: 1.

the rest is the same as in example 1.

Example 8

the molar ratio of the four modified maleimides is 1: 1: 1: 1.

the rest is the same as in example 1.

Example 9

the molar ratio of the four modified maleimides is 1: 1: 1: 1.

the rest is the same as in example 1.

Example 10

the molar ratio of the five modified maleimides is 1: 1: 1: 1: 1.

the rest is the same as in example 1.

Example 11

in the examples of the present application, N330 carbon black was changed to N550 carbon black in total in addition to example 1.

Example 12

in the embodiment of the present application, all the white carbon black is replaced with N330 carbon black based on embodiment 1.

Comparative example 1

The application and the comparative example provide a composition for preparing rubber compound, the rubber compound and a preparation method thereof:

the comparative example of the present application has no vulcanizing agent composition on the basis of example 1, and the amount of sulfur is increased to 2.3 parts by weight and the amount of accelerator NS is increased to 1.5 parts by weight. The rest is the same as in example 1.

Comparative example 2

The comparative example of the application provides a composition for preparing a rubber compound, the rubber compound and a preparation method thereof:

comparative example of the present application a vulcanizing agent composition was changed to 2 parts by weight of modified maleimide based on example 1, and its chemical formula was as follows:

the rest is the same as in example 1.

Test example 1

The vulcanization characteristics of examples 1, 5, 11 and comparative examples 1-2 were tested by an MDR 2000 rheometer, the rheometer graph is shown in FIG. 1, and the test results are shown in Table 1.

TABLE 1 vulcanization characteristics of examples 1, 5, 11 and comparative examples 1-2

As can be seen from Table 1 and FIG. 1, the formulations containing the novel vulcanizing agent (examples 1, 5, 11) have better reversion resistance than comparative example 1 because the compound of comparative example 1 contains more polysulfide bonds, and the compound has better thermal stability when subjected to high temperature applications because non-sulfur crosslinks are formed after the novel vulcanizing agent is added.

Test example 2

The compositions for preparing rubber compounds of examples 1, 5, 11 and comparative examples 1 to 2 were placed in a cavity of a rubber processing analyzer RPA2000, set at a frequency of 1.7Hz and a strain of 2.8%, subjected to positive vulcanization at 151 ℃ for 20min, cooled to 90 ℃ and thermostated, and tested for tan δ to strain relationship. Scanning the strain range of 0.01-10% at a frequency of 10Hz, and the test result is shown in FIG. 2.

As can be seen from FIG. 2, examples 1, 5, and 11 all have lower dynamic loss tan δ, and example 5 has lower dynamic loss tan δ than example 1, indicating that the compound has better dynamic properties when two or more modified maleimides are used in the vulcanizing agent composition; comparative example 1, which has the highest dynamic loss tan δ, and comparative example 2, shows that the addition of the novel curative improves the dynamic properties of the compound, but the optimum dynamic properties are not obtained with the single curative.

The compositions for preparing rubber compounds of examples 1, 5, 11 and comparative examples 1 to 2 were placed in a cavity of a rubber processing analyzer RPA2000, set at a frequency of 1.7Hz and a strain of 2.8%, subjected to normal vulcanization at 151 ℃ for 20min, cooled to 40 ℃ and thermostated, and tested at a frequency of 10Hz for tan. delta. in relation to temperature of 40 ℃ to 150 ℃ with the results shown in FIG. 3.

From FIG. 3, it can be similarly concluded that the formulations in the examples have the lowest dynamic loss of tan δ, compared to comparative example 1, which has the highest tan δ, indicating that the formulations of the examples have the lowest heat generation, and that the dynamic loss of tan δ of example 5, which is lower than that of example 1, indicates that the compound has better dynamic properties when two or more modified maleimides are used in the vulcanizing agent composition.

Test example 3

The tensile properties, tear strength and hardness of the rubber compounds obtained in examples 1, 5 and 11 and comparative examples 1 to 2 were measured at a positive vulcanization condition of 151 ℃ for 20min, as shown in Table 2.

The tensile properties, tear strength and hardness of the rubber compounds obtained in examples 1, 5 and 11 and comparative examples 1 to 2 were measured under an overcuring condition of 151 ℃ for 180min, as shown in Table 3.

The tensile properties, tear strength and hardness of the rubber compounds obtained in examples 1, 5 and 11 and comparative examples 1 to 2 were measured after anaerobic heat aging at a positive vulcanization condition of 151 ℃ for 20min and at 100 ℃ for 144h, as shown in Table 4.

The tensile properties, tear strength, and hardness of the rubber compounds obtained in examples 1, 5, and 11 and comparative examples 1 to 2 were changed as shown in table 5 before and after the oxygen-free heat aging under the positive vulcanization conditions of 151 ℃ for 20min and 100 ℃ for 144 h.

TABLE 2 physical Properties (curing conditions 151 ℃ C. 20 min.) of the rubber mixtures obtained in examples 1, 5 and 11 and comparative examples 1 to 2

TABLE 3 physical Properties (OVER-CURING CONDITION OF 151 ℃ C. 180 min.) of the rubber mixtures obtained in examples 1, 5, 11 and comparative examples 1 to 2

TABLE 4 physical properties 100 ℃ C.. times.144 h of the rubber mixtures obtained in examples 1, 5, 11 and comparative examples 1 to 2 after anaerobic thermal aging

TABLE 5 Change Rate before and after anaerobic Heat aging of rubber mixes prepared in examples 1, 5, 11 and comparative examples 1 to 2

The positive vulcanization and the over vulcanization are respectively carried out at the temperature of 151 ℃ for 20min and the temperature of 151 ℃ for 180min, and as can be seen from tables 2 and 3, the optimal modulus, hardness and tear strength of the formulas of the comparative example and the example after the positive vulcanization are almost the same, but after the over vulcanization, the modulus of the comparative example 1 is reduced, and the modulus of the formula added with the novel vulcanizing agent is increased, which shows that the rubber compound added with the novel vulcanizing agent has better reversion resistance, and simultaneously means that the formula added with the novel vulcanizing agent has high temperature resistance, which is better for the application of the tire rubber compound.

After the rubber compound which is normally vulcanized for 20min at 151 ℃ is subjected to anaerobic thermal aging under the condition of 100 ℃ multiplied by 144h, tables 4 and 5 show that after the anaerobic aging, the modulus and the hardness of each formula are increased in different degrees, the tensile strength and the elongation at break are reduced in different degrees, wherein the physical property change rate of the comparative example 1 is the largest, which shows that the comparative example 1 has the worst thermal aging resistance compared with the formula added with the novel vulcanizing agent; the rate of change of example 5 is minimal, indicating that example 5 has optimal heat aging resistance; the rate of change of example 1 is lower than that of comparative example 2, indicating that the optimum aging resistance is not obtained with a single curing agent.

Test example 4

The compounds prepared in examples 1, 5 and 11 and comparative examples 1 to 2 were subjected to dynamic heat buildup test using a Japanese Ueshima FT-1250 constant stress/strain bender under the ISO4666-4-2007 standard method. Under constant stress conditions, the static load was 100.0N, the dynamic load was 1000.0N, the temperature was 50 ℃ and the frequency was 10Hz, and Table 6 gives the results of the measurements of the increase in the temperature at the bottom and in the center of the sample.

TABLE 6 dynamic Heat buildup

Detecting items	Comparative example 1	Comparative example 2	Example 1	Example 5	Example 11
						Bottom temperature rise/deg.C	16	11	9	8	9
Temperature rise mid temperature/. degree.C	46.6	31.5	26.7	25.9	27.7

As can be seen from Table 6, examples 1, 5 and 11 all have relatively low heat generation temperatures, and example 5 has lower heat generation than example 1, indicating that compounds have lower heat generation when two or more modified maleimides are selected for use in the vulcanizing agent composition; comparative example 1 produced the highest heat generation, and comparative example 2 produced less heat generation than the examples, indicating that the addition of the novel curative reduced the compound's dynamic heat generation, but the curative alone did not produce the optimum heat generation.

Test example 5

Similar DMA tests were performed on rubber mixes prepared in examples 1, 5, 11 and comparative examples 1-2 using a Mettler Toledo SDTA 861e with a dynamic thermomechanical analyzer. The test conditions were: the temperature was 30 ℃ to 100 ℃, the static stress was 10N, the amplitude was 15 μm, and the temperature rise rate was 3 ℃/min, and the results are shown in Table 7.

TABLE 7 tan. delta. of the mixtures obtained in examples 1, 5 and 11 and comparative examples 1 to 2

As can be seen from Table 7, examples 1, 5 and 11 all have lower dynamic loss tan δ, and example 5 has lower dynamic loss tan δ than example 1, indicating that the compound has better dynamic properties when two or more modified maleimides are selected for the vulcanizing agent composition; comparative example 1, which has the highest dynamic loss tan δ, and comparative example 2, shows that the addition of the novel curative improves the dynamic properties of the compound, but the optimum dynamic properties are not obtained with the single curative.

The foregoing is illustrative of the present application and is not to be construed as limiting thereof, as numerous modifications and variations will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. The composition for preparing the rubber compound is characterized by comprising 100 parts by weight of rubber, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of an accelerator, 0.5-4 parts by weight of an activator and 0.5-7 parts by weight of a vulcanizing agent composition;

the vulcanizing agent composition comprises a modified maleimide, an alkylphenol disulfide, and 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane;

the modified maleimide includes at least two of the following compounds:

the activating agent is zinc benzoate.

2. A composition for use in the preparation of a rubber compound according to claim 1, wherein said vulcanizing agent composition comprises 0.1 to 3 parts of modified maleimide, 0.1 to 2 parts of alkylphenol disulfide and 0.1 to 2 parts of 1, 6-bis (N, N' -dibenzylthiocarbamoyldithio) -hexane.

3. A composition for preparing rubber compound as claimed in claim 1, wherein said composition further comprises a filler, and said filler comprises 1-90 parts by weight of carbon black and/or 1-85 parts by weight of white carbon black.

4. A composition for preparing rubber compound as claimed in claim 1, wherein the composition for preparing rubber compound further comprises 0.1-8.5 parts by weight of silane coupling agent.

5. A composition for use in the preparation of a mix as claimed in claim 4, characterised in that said silane coupling agent comprises any one or more of bis- [ (triethoxysilyl) propyl ] tetrasulphide, bis- [ (triethoxysilyl) propyl ] disulphide and 3-octanoylthio-1-propyltriethoxysilane.

6. A method for preparing a rubber compound, the method comprising: mixing 100 parts by weight of rubber, 1-175 parts by weight of filler, 0.1-8.5 parts by weight of silane coupling agent and 0.5-4 parts by weight of activator to prepare master batch, and mixing the master batch, 1-5 parts by weight of sulfur, 0.5-3 parts by weight of accelerator and 0.5-7 parts by weight of vulcanizing agent composition to prepare final rubber to prepare rubber compound;

the modified maleimide includes at least two of the following compounds:

the activating agent is zinc benzoate.

7. A rubber composition, characterized in that it is prepared by the method for preparing a rubber composition according to claim 6.

8. A tire, characterized in that it is made with the mix of claim 7.