Lightweight high-strength rubber composition for shoe sole, lightweight high-strength rubber shoe sole and application

Abstract

The invention belongs to the field of high polymer materials, and discloses a light high-strength rubber composition for soles, which comprises the following components in parts by weight: 1300-1450 parts of high cis-polybutadiene composite rubber VCR412; 50 to 400 parts of isoprene rubber SKI-3350; 410 to 460 parts of high styrene rubber HS-860; 300 to 350 parts of white carbon black; 20-30 parts of zinc oxide; 8-12 parts of microcrystalline wax; 40 to 50 parts of a hydrocarbon resin mixture RH-100; and 240 to 280 parts of glass microspheres. According to the composition, the optimized main rubber composition is matched with the hydrocarbon resin mixture RH-100, so that the compatibility of the main rubber and the glass microspheres is improved, the specific gravity of the sole is effectively reduced, and the sole has satisfactory abrasion and strength. Meanwhile, the invention also discloses application of the composition and a light high-strength rubber sole.

Description

Technical Field

[0001] The invention relates to the field of polymer materials, and in particular to a lightweight and high-strength rubber composition for shoe soles, a lightweight and high-strength rubber sole and applications thereof. Background Art

[0002] The applicant previously filed an invention patent application CN113388119B for a method for preparing a polyhydroxysilane-modified butadiene rubber and an ozone-resistant rubber. The soles prepared using the rubber composition have high-strength and antioxidant properties. The main rubber used is natural rubber, butadiene rubber, nitrile rubber, and modified butadiene rubber. The rubber composition is not suitable for preparing lightweight and high-strength soles.

[0003] Today's lightweight soles can be roughly divided into polyurethane foam soles and rubber soles. The relative density of polyurethane foam soles can be as low as 0.5 or less, and it has many advantages, but it does not have advantages in water absorption, yellowing resistance, and fracture performance.

[0004] Rubber soles do not have the above-mentioned defects except for their relatively high density; lightweight rubber soles are currently a key research direction in this field;

[0005] Using glass microspheres to lighten rubber soles is an effective approach. However, this approach can easily lead to reduced mechanical strength of the soles. To solve this problem, most techniques in the art can only be implemented through surface modification of glass microspheres.

[0006] The publication number is CN114525007A, and the subject is a patent application for a lightweight, crack-resistant rubber sole and a preparation method thereof. The sole is optimized through the main rubber formula and uses approximately 15wt% of glass microspheres relative to the main rubber to achieve lightweight. The DIN abrasion is above 150, and there is no strength data.

[0007] The publication number is CN114716787A, and the subject is a patent application for a lightweight masterbatch added to rubber soles and the sole rubber material thereof. Petroleum resin is used as the main rubber, and graded glass microspheres and chopped fibers are used to achieve lightness and strength.

[0008] In the prior art, there are few technologies related to lightweight transformation of non-foamed rubber soles.

[0009] Therefore, the technical problem solved by the present invention is: how to develop a lightweight and high-strength rubber composition to prepare a shoe sole. Summary of the invention

[0010] The purpose of the present invention is to provide a lightweight and high-strength rubber composition, which adopts an optimized main rubber composition and a hydrocarbon resin mixture RH-100 to improve the compatibility of the main rubber and glass microspheres, effectively reduce the specific gravity of the sole, and have satisfactory wear and strength.

[0011] At the same time, the invention also discloses an application of the composition and a lightweight and high-strength rubber sole.

[0012] To achieve the above objectives, this application discloses:

[0013] A lightweight and high-strength rubber composition for shoe soles, characterized in that it comprises the following components in parts by weight:

[0014] High cis polybutadiene composite rubber VCR412 1300-1450 parts;

[0015] Isoprene rubber SKI-3S 350-400 parts;

[0016] High styrene rubber HS-860 410-460 parts;

[0017] 300-350 parts of white carbon black;

[0018] 20-30 parts of zinc oxide;

[0019] 8-12 parts of microcrystalline wax;

[0020] 40-50 parts of hydrocarbon resin mixture RH-100;

[0021] 240-280 parts of glass microspheres.

[0022] In the main rubber of the present invention, the high cis polybutadiene composite rubber VCR412 has strong wear resistance, the isoprene rubber SKI-3S has excellent high elasticity, the high styrene rubber HS-860 has extremely strong compatibility with the high cis polybutadiene composite rubber VCR412 and the isoprene rubber SKI-3S, and can significantly reinforce the high cis polybutadiene composite rubber VCR412, so that the strength of the main rubber can reach a certain level; in order to achieve the lightweight of the rubber composition, micron-sized hollow glass micro- In order to reduce the influence of micron-sized hollow glass microspheres on the strength and wear resistance of the rubber composition, a hydrocarbon resin mixture RH-100 is used. The resin mixture serves as a connecting bridge between the hollow glass microspheres and the main rubber to improve the compatibility between the two. The hydrocarbon resin mixture RH-100 is used in the tire airtight rubber layer to improve the physical properties and flex crack resistance of the brominated butyl rubber. In the formulation of the present invention, it mainly plays the role of a compatibilizer and a structural reinforcing agent to achieve the lightweight and high-strength transformation purposes of the rubber.

[0023] As a commonly used method in this field, in order to further improve the strength and wear resistance of the main rubber, white carbon black is used as a reinforcing filler and zinc oxide is used as an auxiliary reinforcing filler. Microcrystalline wax can improve the wear resistance and anti-slip properties of rubber to a certain extent and improve the strength of rubber.

[0024] The above-mentioned solution is the main component of the composition of the present invention, and the remaining components such as coupling agents, activators, antiozonants, antioxidants, etc. can be selected and used according to actual needs;

[0025] As is well known in the art, the above-mentioned rubber must be vulcanized, and the vulcanization aids can be the aids commonly used in the art.

[0026] The rubber composition further comprises the following components in parts by weight:

[0027] Silane coupling agent HP-669 20-25 parts;

[0028] Active agent PEG-4000 20-25 parts;

[0029] Anti-aging agent 20-25 parts;

[0030] 20-25 parts of antiozonant;

[0031] And a vulcanization processing aid, the vulcanization processing aid is composed of the following components in parts by weight:

[0032] Accelerator zinc dialkyl dithiophosphate 20-25 parts;

[0033] Accelerator: 6-7 parts of dibenzothiazole disulfide;

[0034] 30-35 parts of insoluble sulfur.

[0035] In the present invention, various accelerators were tested, such as N-tert-butyl-2-benzothiazole sulfenamide, zinc dialkyl dithiophosphate, dibenzothiazole disulfide, etc. It was found that zinc dialkyl dithiophosphate as the main accelerator and dibenzothiazole disulfide as the auxiliary accelerator can achieve effective improvement in wear resistance and strength;

[0036] Generally speaking, the most commonly used vulcanization accelerators are thiazoles, sulfonamides, and dithiophosphates / esters. In a large number of application scenarios, better results can be achieved by using them in combination; for rubber compositions with glass microspheres, thiazoles and dithiophosphates are the most preferred accelerators.

[0037] At the same time, the invention also discloses the use of the rubber composition as described above to prepare the sole.

[0038] In addition, the present invention also discloses a lightweight and high-strength rubber sole and a preparation method thereof, which are prepared by using the rubber composition as described above.

[0039] The method for preparing the above-mentioned lightweight and high-strength rubber sole comprises the following steps:

[0040] Mixing: Add high cis polybutadiene composite rubber VCR412, isoprene rubber SKI-3S, high styrene rubber HS-860, hydrocarbon resin mixture RH-100 into a 10,000 horsepower machine and mix for 30-40 minutes; then add 2 / 3 of white carbon black and mix for 50-70 minutes; add the remaining white carbon black and other additives except the vulcanization processing aid and mix for 90-110 minutes; unload, and control the unloading temperature below 130°C;

[0041] Open mill: unload the rubber material from the 10,000 horsepower machine, turn the material over on the turner, and then roll the material out of the sheet. The temperature of the rubber material is controlled below 40℃ and put into the storage room for aging. The aging time is at least 4 hours. The temperature of the open mill should not exceed 80℃. After mixing and adding sulfur in the open mill, turn the material for 5 to 10 minutes until the sulfur is evenly dispersed, and then roll the material out of the sheet.

[0042] Vulcanization: Vulcanization mold temperature 155 ~ 160 ℃; oil pressure controlled at 150kg / cm 2 ~160kg / cm 2 ; Molding time 280~320s.

[0043] This application has at least the following beneficial effects:

[0044] The composition adopts an optimized main rubber composition and a hydrocarbon resin mixture RH-100 to improve the compatibility of the main rubber and the glass microspheres, effectively reduce the specific gravity of the sole, and at the same time have satisfactory wear and strength.

[0045] In the main rubber of the present invention, the high cis polybutadiene composite rubber VCR412 has strong wear resistance, the isoprene rubber SKI-3S has excellent high elasticity, the high styrene rubber HS-860 has extremely strong compatibility with the high cis polybutadiene composite rubber VCR412 and the isoprene rubber SKI-3S, and can significantly reinforce the high cis polybutadiene composite rubber VCR412, so that the strength of the main rubber can reach a certain level; in order to achieve the lightweight of the rubber composition, micron-sized hollow glass micro- In order to reduce the influence of micron-sized hollow glass microspheres on the strength and wear resistance of the rubber composition, a hydrocarbon resin mixture RH-100 is used. The resin mixture serves as a connecting bridge between the hollow glass microspheres and the main rubber to improve the compatibility between the two. The hydrocarbon resin mixture RH-100 is used in the tire airtight rubber layer to improve the physical properties and flex crack resistance of the brominated butyl rubber. In the formulation of the present invention, it mainly plays the role of a compatibilizer and a structural reinforcing agent to achieve the lightweight and high-strength transformation purposes of the rubber. DETAILED DESCRIPTION

[0046] Below in conjunction with embodiments of the present invention, the present invention is clearly and completely described. In the description of the present invention, it should be noted that, in the embodiments, those not indicating specific conditions, are carried out according to the conditions of normal conditions or manufacturer's suggestions. Reagents used or instruments not indicating manufacturers are conventional products that can be obtained by commercial purchase. In the case of not making special instructions, the parts used in the embodiments of the present invention are all parts by weight.

[0047] A method for preparing a lightweight and high-strength rubber sole comprises the following steps:

[0048] Mixing: Add high cis polybutadiene composite rubber VCR412, isoprene rubber SKI-3S, high styrene rubber HS-860, hydrocarbon resin mixture RH-100 into a 10,000 horsepower machine and mix for 35 minutes; then add 2 / 3 of white carbon black and mix for 60 minutes; add the remaining white carbon black and other additives except the vulcanization processing aid and mix for 100 minutes; unload, and control the unloading temperature below 130°C;

[0049] Open mixing: unload the rubber material from the 10,000 horsepower machine, turn the material over on the turning machine, and then roll the material out of the sheet. The temperature of the rubber material is controlled below 40℃ and put into the storage room for aging. The aging time is 5 hours. The temperature of the open mixing machine should not exceed 80℃. After mixing and adding sulfur in the open mixing machine, turn the material for 8 minutes until the sulfur is evenly dispersed, and then roll the material out of the sheet.

[0050] Vulcanization: Vulcanization mold temperature 155 ~ 160 ℃; oil pressure controlled at 150kg / cm 2 ~160kg / cm 2; Molding time 300s.

[0051] The formula is shown in Table 1 below;

[0052] Table 1 Formula Unit: g

[0053]

[0054]

[0055] The CAS number of antioxidant CPL is 68610-51-5;

[0056] Comparative Example 5

[0057] The same as Example 1, except that C9 petroleum resin is used in an equal weight amount to replace the resin RH-100.

[0058] Comparative Example 6

[0059] The method is substantially the same as Example 1, except that an equal weight amount of C5 petroleum resin is used to replace the resin RH-100.

[0060] Comparative Example 7

[0061] The process is substantially the same as Example 1, except that an equal weight amount of N-tert-butyl-2-benzothiazolesulfenamide is used to replace the accelerator SW50 GE / F150.

[0062] Performance Testing

[0063] Performance tests include: hardness, relative density, abrasion, tear strength, elongation at break, and tensile strength. The test methods all adopt Adidas standards, as shown in Table 2 below;

[0064] Table 2 Test results

[0065]

[0066]

[0067] Result analysis:

[0068] 1. It can be seen from Examples 1 to 3 that the relative density of the sole prepared by the rubber composition of the present invention can reach about 1.0, achieving lightweight soles; its wear is less than 75, and its strength reaches the index required by the standard;

[0069] 2. It can be seen from Comparative Examples 1, 2, 5 and 6 that the amount of resin RH-100 needs to be controlled at a reasonable level, otherwise it will increase wear and reduce strength; when other similar petroleum resins are used, their wear and strength are significantly reduced, which shows that resin RH-100 can significantly improve the compatibility between glass microspheres and the main glue;

[0070] 3. Comparative Examples 3 and 4 show that excessive or insufficient use of isoprene rubber and high styrene rubber will increase wear. High styrene rubber can increase the strength of the rubber composition, but reduce its elongation at break. The appropriate proportion of isoprene rubber and high styrene rubber can achieve simultaneous improvement in strength and elongation at break.

[0071] 4. Comparative Example 7 shows that, unlike the prior application of the present applicant, thiazole and dithiophosphate accelerators are the most preferred for the rubber composition with glass microspheres. The use of thiazole and sulfonamide accelerators can improve strength, but have no significant effect on the reduction of wear and relative density.

[0072] 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-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the elements are encompassed by the present invention.

Claims

1. A lightweight and high-strength rubber composition for shoe soles, characterized in that: The invention comprises the following components in parts by weight: 1300 to 1450 parts of high cis polybutadiene composite rubber VCR412; Isoprene rubber SKI-3S 350-400 parts; High styrene rubber HS-860 410-460 parts; 300-350 parts of white carbon black; 20-30 parts of zinc oxide; 8-12 parts of microcrystalline wax; 40-50 parts of hydrocarbon resin mixture RH-100; 240-280 parts of glass microspheres.

2. The rubber composition according to claim 1, characterized in that The following components are also included in parts by weight: 20 to 25 parts of silane coupling agent HP-669; Active agent PEG-4000 20-25 parts; Anti-aging agent 20-25 parts; 20-25 parts of antiozonant; And a vulcanization processing aid, the vulcanization processing aid is composed of the following components in parts by weight: Accelerator zinc dialkyl dithiophosphate 20-25 parts; Accelerator: 6-7 parts of dibenzothiazole disulfide; 30-35 parts of insoluble sulfur.

3. Use of the rubber composition according to claim 1 or 2 in preparing shoe soles.

4. A lightweight and high-strength rubber sole, characterized in that: The adhesive composition is prepared by using the adhesive composition as claimed in claim 1 or 2.

5. A method for preparing a lightweight and high-strength rubber sole as claimed in claim 4, characterized in that: The steps include: Mixing: Add high cis polybutadiene composite rubber VCR412, isoprene rubber SKI-3S, high styrene rubber HS-860, hydrocarbon resin mixture RH-100 into a 10,000 horsepower machine and mix for 30-40 minutes; then add 2 / 3 of white carbon black and mix for 50-70 minutes; add the remaining white carbon black and other additives except the vulcanization processing aid and mix for 90-110 minutes; unload, and control the unloading temperature below 130°C; Open mill: unload the rubber material from the 10,000 horsepower machine, turn the material over on the turner, and then roll the material out of the sheet. The temperature of the rubber material is controlled below 40℃ and put into the storage room for aging. The aging time is at least 4 hours. The temperature of the open mill should not exceed 80℃. After mixing and adding sulfur in the open mill, turn the material for 5 to 10 minutes until the sulfur is evenly dispersed, and then roll the material out of the sheet. Vulcanization: Vulcanization mold temperature 155 ~ 160 ℃; oil pressure controlled at 150kg / cm 2 ~160kg / cm 2 ; Molding time 280~320s.

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