Composite material based on recycled rubber and application of composite material in shoe sole

Abstract

The invention provides a composite material based on recycled rubber and application of the composite material in soles. The composite material comprises the following components in parts by mass: 30-50 parts of recycled rubber, 30-60 parts of natural rubber, 20-50 parts of styrene butadiene rubber, 30-60 parts of butadiene rubber, 15-30 parts of modified halloysite, 1-10 parts of sulfur, 0.1-3 parts of rosin, 0.1-3 parts of zinc oxide, 0.5-2 parts of an accelerant and 1-5 parts of an auxiliary agent. Wherein the modified halloysite is obtained by reacting a silane coupling agent, a cross-linking agent, vinyl silicone rubber, SBS rubber and halloysite. According to the invention, the bonding strength among different components is enhanced, and a more tough cross-linked structure is formed, so that the composite material has more excellent comprehensive performance, meets the requirements of soles for material performance, solves the problems in the prior art, and has important significance for the development of rubber products.

Description

Technical Field

[0001] The invention relates to the technical field of rubber materials, and in particular to a composite material based on recycled rubber and application thereof in shoe soles. Background Art

[0002] Vulcanized rubber soles are a type of rubber material that has been treated by vulcanization and are widely used in footwear manufacturing. The vulcanization process heats the rubber and adds vulcanizing agents such as sulfur to crosslink the rubber molecules, improving their elasticity, wear resistance and aging resistance. This technology originated in the 19th century and is still one of the mainstream processes for sole manufacturing.

[0003] With the continuous development of sustainable development and green environmental protection concepts, recycled rubber has been more and more widely used. Using recycled rubber in shoe soles has important environmental and economic value. By crushing and modifying waste rubber products (such as tires, shoe soles, etc.), and then reusing them, it not only reduces production costs, but also reduces the pollution of rubber waste to the environment, and promotes the development of the circular economy.

[0004] Existing technologies such as CN109957156A and CN114957824A all use recycled rubber mixed with natural rubber and synthetic rubber as components of the sole to improve the overall performance. However, since the recycled rubber powder has undergone cross-linking reaction, it is difficult to participate in the vulcanization process of the base rubber, resulting in insufficient interface bonding strength between different materials, which has an adverse effect on the mechanical properties of the composite material and the sole made thereof.

[0005] Therefore, how to ensure the elasticity, toughness, impact resistance and wear resistance of rubber composite materials to meet the performance requirements of different environments and scenarios is a difficult problem faced by this field.

[0006] In summary, it is necessary to develop a new technical solution to solve the problems existing in the prior art. Summary of the invention

[0007] Based on this, the present invention provides a composite material based on recycled rubber and its application in the sole. By modifying the halloysite, introducing a variety of functional groups, and compounding with activated recycled rubber, natural rubber and other components, the bonding strength between different components is enhanced, and a stronger cross-linked structure is formed, so that the composite material has better comprehensive performance, meets the requirements of the sole for material performance, solves the problems existing in the prior art, and is of great significance to the development of rubber products.

[0008] An object of the present invention is to provide a composite material based on recycled rubber, wherein the composite material based on recycled rubber comprises the following components in parts by weight:

[0009]

[0010]

[0011] in,

[0012] The modified halloysite is obtained by reacting a silane coupling agent, a crosslinking agent, vinyl silicone rubber, SBS rubber and halloysite.

[0013] Furthermore, the crosslinking agent is trimethylolpropane triacrylate.

[0014] Furthermore, the recycled rubber is pre-treated by activation.

[0015] Furthermore, the auxiliary agent is selected from one or more of a dispersant, a plasticizer, an antioxidant, a foaming agent, an initiator, and a catalyst.

[0016] Another object of the present invention is to provide a method for preparing the composite material based on recycled rubber, the method for preparing the composite material based on recycled rubber comprising the following steps:

[0017] S1, mixing and heating halloysite and a silane coupling agent to obtain pretreated halloysite;

[0018] S2, mixing the pretreated halloysite with a crosslinking agent and an initiator, heating for reaction, adding vinyl silicone rubber and SBS rubber, and continuing the reaction to obtain modified halloysite;

[0019] S3, mixing the modified halloysite, recycled rubber, natural rubber, styrene-butadiene rubber, butadiene rubber, rosin, zinc oxide and additives, and performing internal mixing and open mixing to obtain a base material;

[0020] S4, mixing the base material, sulfur and accelerator, and performing vulcanization after milling to obtain a composite material based on recycled rubber.

[0021] Furthermore, in step S1, the mass ratio of the halloysite to the silane coupling agent is 1:(0.2-2).

[0022] Furthermore, the silane coupling agent is KH-570 (γ-methacryloxypropyltrimethoxysilane).

[0023] Furthermore, in step S2, the mass ratio of the pretreated halloysite, the crosslinking agent, the vinyl silicone rubber and the SBS rubber is 1:(0.1-0.5):(0.5-3):(0.1-1).

[0024] Furthermore, in step S3, the pressure of the banburying is 1-2 MPa.

[0025] Another object of the present invention is to provide application of the composite material based on recycled rubber in shoe soles.

[0026] The present invention has the following beneficial effects:

[0027] The invention provides a composite material based on recycled rubber. The modified halloysite is used as a component. KH-570 is firstly used for treatment to introduce double bonds. Then trimethylolpropane triacrylate is used as a crosslinking agent to graft with vinyl silicone rubber and SBS rubber. Silicone rubber segments and SBS toughening segments are further introduced. On the one hand, the compatibility between the modified halloysite and the polymer rubber material is improved, and the wear resistance, toughness and other capabilities of the composite material are improved by the flexible polysiloxane segments and SBS segments coated on the outer layer. On the other hand, the flexible segments of the outer layer of the modified halloysite have a branched structure and contain crosslinkable double bonds, so they can be crosslinked with other natural rubbers and synthetic rubbers, thereby improving the crosslinking density of the composite material. Long chains can also be entangled with each other to form a more three-dimensional network crosslinking structure. The halloysite embedded in the crosslinking system can also better play a filling and reinforcing role, thereby improving the wear resistance and stability of the composite material.

[0028] The present invention also uses recycled rubber as a component. After activation, this component has higher activity, can participate in the vulcanization process, and cross-link with modified halloysite, natural rubber and other components, thereby improving the bonding strength between the components, promoting further improvement of the mechanical properties and stability of the material, and making the product have excellent comprehensive performance, realizing waste utilization, and meeting the footwear industry's demand for material performance. DETAILED DESCRIPTION

[0029] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0030] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0031] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0032] The halloysite in the embodiment of the present invention is halloysite nanotubes with a particle size of 50-100 nm.

[0033] The accelerator in the embodiment of the present invention is accelerator DM.

[0034] The catalyst in the embodiment of the present invention is cupric chloride.

[0035] The antioxidant in the embodiment of the present invention is antioxidant RD.

[0036] The plasticizer in the embodiment of the present invention is polyethylene glycol 4000.

[0037] The vinyl silicone rubber in the embodiment of the present invention is double-terminal vinyl silicone oil with a viscosity of 1000 mPa.s, purchased from Shanghai Silicon Friends.

[0038] The SBS rubber in the embodiment of the present invention is SINOPEC YH-792.

[0039] The recycled rubber in the embodiment of the present invention is recycled tire rubber powder, which is activated and pre-treated before use, including the following steps:

[0040] Recycled tire rubber powder (70 mesh) and B480 regenerated rubber activator (Anhui Jinma) were mixed in a mass ratio of 10:0.5, spread to a thickness of 15 mm, and microwaved for 8 min (2.45 GHz, 800 W) to obtain the product.

[0041] Example 1

[0042] A composite material based on recycled rubber, comprising the following components in parts by weight:

[0043]

[0044] The method for preparing the composite material based on recycled rubber comprises the following steps:

[0045] S1, using toluene as solvent, adding halloysite and KH-570 in a mass ratio of 1:1, reacting at 110° C. for 12 h under a nitrogen atmosphere, filtering, washing, and drying to obtain pretreated halloysite;

[0046] S2, using cyclohexanone as solvent, adding the pretreated halloysite, trimethylolpropane triacrylate and initiator BPO, reacting at 80° C. for 3 h under nitrogen atmosphere, then adding vinyl silicone rubber and SBS rubber, reacting at 100° C. for 12 h, filtering, washing and drying to obtain modified halloysite;

[0047] The mass ratio of pretreated halloysite, trimethylolpropane triacrylate, BPO, vinyl silicone rubber and SBS rubber is 1:0.2:0.1:1:0.5;

[0048] S3, according to the above mass fractions, the modified halloysite, recycled rubber, natural rubber, styrene-butadiene rubber, butadiene rubber, rosin, zinc oxide and additives are mixed, added to a mixer, and mixed at 1.5 MPa and 25 ° C. The mixing is carried out in three stages, the first stage is 5 min, the second stage is 3 min, and the third stage is 1.5 min, and each stage is separated by 15 s; then the mixture is added to an open mill for mixing to obtain a base material with a thickness of 4 mm;

[0049] S4, mixing the base material, sulfur and accelerator, mixing them evenly on an open mill, and then performing compression vulcanization at a temperature of 140° C., a compression weight of 115 kg, and a time of 2 h to obtain a composite material based on recycled rubber.

[0050] Example 2

[0051] A composite material based on recycled rubber, comprising the following components in parts by weight:

[0052]

[0053] The method for preparing the composite material based on recycled rubber comprises the following steps:

[0054] S1, using toluene as solvent, adding halloysite and KH-570 in a mass ratio of 1:1, reacting at 110° C. for 12 h under a nitrogen atmosphere, filtering, washing, and drying to obtain pretreated halloysite;

[0055] S2, using cyclohexanone as solvent, adding the pretreated halloysite, trimethylolpropane triacrylate and initiator BPO, reacting at 80° C. for 3 h under nitrogen atmosphere, then adding vinyl silicone rubber and SBS rubber, reacting at 100° C. for 12 h, filtering, washing and drying to obtain modified halloysite;

[0056] The mass ratio of pretreated halloysite, trimethylolpropane triacrylate, BPO, vinyl silicone rubber and SBS rubber is 1:0.2:0.1:1:0.5;

[0057] S3, according to the above mass fractions, the modified halloysite, recycled rubber, natural rubber, styrene-butadiene rubber, butadiene rubber, rosin, zinc oxide and additives are mixed, added to a mixer, and mixed at 1.5 MPa and 25 ° C. The mixing is carried out in three stages, the first stage is 5 min, the second stage is 3 min, and the third stage is 1.5 min, and each stage is separated by 15 s; then the mixture is added to an open mill for mixing to obtain a base material with a thickness of 4 mm;

[0058] S4, mixing the base material, sulfur and accelerator, mixing them evenly on an open mill, and then performing compression vulcanization at a temperature of 140° C., a compression weight of 115 kg, and a time of 2 h to obtain a composite material based on recycled rubber.

[0059] Example 3

[0060] A composite material based on recycled rubber, comprising the following components in parts by weight:

[0061]

[0062] The method for preparing the composite material based on recycled rubber comprises the following steps:

[0063] S1, using toluene as solvent, adding halloysite and KH-570 in a mass ratio of 1:1, reacting at 110° C. for 12 h under a nitrogen atmosphere, filtering, washing, and drying to obtain pretreated halloysite;

[0064] S2, using cyclohexanone as solvent, adding the pretreated halloysite, trimethylolpropane triacrylate and initiator BPO, reacting at 80° C. for 3 h under nitrogen atmosphere, then adding vinyl silicone rubber and SBS rubber, reacting at 100° C. for 12 h, filtering, washing and drying to obtain modified halloysite;

[0065] The mass ratio of pretreated halloysite, trimethylolpropane triacrylate, BPO, vinyl silicone rubber and SBS rubber is 1:0.2:0.1:1:0.5;

[0066] S3, according to the above mass fractions, the modified halloysite, recycled rubber, natural rubber, styrene-butadiene rubber, butadiene rubber, rosin, zinc oxide and additives are mixed, added to a mixer, and mixed at 1.5 MPa and 25 ° C. The mixing is carried out in three stages, the first stage is 5 min, the second stage is 3 min, and the third stage is 1.5 min, and each stage is separated by 15 s; then the mixture is added to an open mill for mixing to obtain a base material with a thickness of 4 mm;

[0067] S4, mixing the base material, sulfur and accelerator, mixing them evenly on an open mill, and then performing compression vulcanization at a temperature of 140° C., a compression weight of 115 kg, and a time of 2 h to obtain a composite material based on recycled rubber.

[0068] Comparative Example 1

[0069] A composite material based on recycled rubber. The difference between this comparative example and Example 1 is that the recycled rubber is not pre-activated, and the remaining components and preparation method are the same as those of Example 1.

[0070] Comparative Example 2

[0071] A composite material based on recycled rubber. The difference between this comparative example and Example 1 is that step S2 is deleted, pretreated halloysite is used to replace modified halloysite, and the remaining components and preparation method are the same as those in Example 1.

[0072] Comparative Example 3

[0073] A composite material based on recycled rubber. The difference between this comparative example and Example 1 is that step S2 is replaced by:

[0074] Using cyclohexanone as solvent, adding the pretreated halloysite, initiator BPO and vinyl silicone rubber, reacting at 100° C. for 12 hours under nitrogen atmosphere, filtering, washing and drying to obtain modified halloysite;

[0075] Among them, the mass ratio of pretreated halloysite, BPO, and vinyl silicone rubber is 1:0.1:1;

[0076] The remaining ingredients and preparation method are the same as those in Example 1.

[0077] Test Case

[0078] The performance tests were performed on the recycled rubber-based composite materials prepared in Examples 1-3 and Comparative Examples 1-3.

[0079] Test method:

[0080] Tensile strength, elongation at break, DIN abrasion and flexibility tests (25°C) were carried out according to GB / T 528-2009, GB / T 9867-2008 and HG / T 2873-2008 standards.

[0081] The test results are shown in Table 1.

[0082] Table 1 Performance test results

[0083] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Tensile strength(MPA) 18.7 19.4 19.9 13.3 11.9 14.4 Elongation at break (%) 434.8 439.0 442.6 381.9 344.5 396.8 <![CDATA[DIN wear (mm 3 )]]> 110.3 106.7 103.5 130.0 148.5 126.1 Flexion (50,000 times) No cracks No cracks No cracks Cracks appear Cracks appear No cracks

[0084] According to Table 1, it can be seen that the bonding strength of multiple components in the composite materials based on recycled rubber prepared in Examples 1-3 is high, and a good network cross-linking structure can be formed, synergistic efficiencies are achieved, the mechanical strength of the composite materials is effectively improved, and the composite materials have excellent comprehensive performance. Comparative Examples 1-3 replaced the modified halloysite or recycled rubber, and different substances could not be fully cross-linked, so the stability, uniformity, and bonding degree of the materials were not ideal, and the performance was significantly reduced.

[0085] In summary, the composite material based on recycled rubber of the present invention has excellent performance, overcomes the defects existing in the prior art, and has good application prospects.

[0086] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0087] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A composite material based on recycled rubber, characterized in that: The composite material based on recycled rubber comprises the following components in parts by weight: in, The modified halloysite is obtained by reacting a silane coupling agent, a crosslinking agent, vinyl silicone rubber, SBS rubber and halloysite.

2. The composite material based on recycled rubber according to claim 1, characterized in that: The crosslinking agent is trimethylolpropane triacrylate.

3. The composite material based on recycled rubber according to claim 1, characterized in that: The recycled rubber is pre-treated by activation.

4. The composite material based on recycled rubber according to claim 1, characterized in that: The auxiliary agent is selected from one or more of a dispersant, a plasticizer, an antioxidant, a foaming agent, an initiator, and a catalyst.

5. The method for preparing a composite material based on recycled rubber according to any one of claims 1 to 4, characterized in that: The method for preparing the composite material based on recycled rubber comprises the following steps: S1, mixing and heating halloysite and a silane coupling agent to obtain pretreated halloysite; S2, mixing the pretreated halloysite with a crosslinking agent and an initiator, heating and reacting, adding vinyl silicone rubber and SBS rubber, and continuing the reaction to obtain modified halloysite; S3, mixing the modified halloysite, recycled rubber, natural rubber, styrene-butadiene rubber, butadiene rubber, rosin, zinc oxide and additives, and performing internal mixing and open mixing to obtain a base material; S4, mixing the base material, sulfur and accelerator, and performing vulcanization after milling to obtain a composite material based on recycled rubber.

6. The method for preparing a composite material based on recycled rubber according to claim 5, characterized in that: In step S1, the mass ratio of the halloysite to the silane coupling agent is 1:(0.2-2).

7. The method for preparing a composite material based on recycled rubber according to claim 6, characterized in that: The silane coupling agent is KH-570.

8. The method for preparing a composite material based on recycled rubber according to claim 5, characterized in that: In step S2, the mass ratio of the pretreated halloysite, the crosslinking agent, the vinyl silicone rubber and the SBS rubber is 1:(0.1-0.5):(0.5-3):(0.1-1).

9. The method for preparing a composite material based on recycled rubber according to claim 5, characterized in that: In step S3, the pressure of the banburying is 1-2 MPa.

10. Use of the composite material based on recycled rubber according to any one of claims 1 to 4 in shoe soles.

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