Lightweight high-strength rubber composition for soles, lightweight high-strength rubber soles and applications thereof

Abstract

The present invention belongs to the field of polymer materials, and discloses a lightweight, high-strength rubber composition for soles, including the following components in parts by weight: 1300-1450 parts of high-cis polybutadiene composite rubber VCR412; 350-400 parts of isoprene rubber SKI-3S; 410-460 parts of high styrene rubber HS-860; 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. The composition adopts an optimized main glue composition to cooperate with hydrocarbon resin mixture RH-100 to improve the compatibility of the main glue and glass microspheres, effectively reducing the specific gravity of the sole while having satisfactory wear and strength. At the same time, the present invention also discloses an application of the composition and a lightweight, high-strength rubber sole.

Description

Technical Field

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

[0002] The applicant previously filed an invention patent application CN113388119B for a method for preparing polyhydroxysilane-modified butadiene rubber and an ozone-resistant aging rubber. The soles prepared using this rubber composition have high-strength and antioxidant properties. The main rubber used is natural rubber, butadiene rubber, nitrile rubber, and modified butadiene rubber. This 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 and has many advantages, but it does not have advantages in water absorption, yellowing resistance, and fracture performance.

[0004] In addition to its relatively high density, rubber soles do not have the above-mentioned defects; lightweight rubber soles are currently a key research direction in this field;

[0005] Using glass microspheres to lightweight rubber soles is an effective approach. However, this approach can easily lead to a reduction in the mechanical strength of the soles. To solve this problem, most techniques in this field involve surface modification of the glass microspheres.

[0006] The patent application, publication number CN114525007A, is for a lightweight, crack-resistant rubber sole and its preparation method. The sole is lightweight by optimizing the main rubber formula and using approximately 15wt% glass microspheres relative to the main rubber. The DIN abrasion resistance 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. It uses petroleum resin as the main rubber and graded glass microspheres and chopped fibers to achieve lightweight and strength.

[0008] In the prior art, there are few technologies for lightweighting 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. The composition 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 at the same time 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, high-strength rubber composition for shoe soles, characterized by comprising 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- To reduce the impact of micron-sized hollow glass microspheres on the strength and wear resistance of the rubber composition, a hydrocarbon resin mixture RH-100 is used. This resin mixture serves as a bridge connecting the hollow glass microspheres and the main rubber, improving 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 bromobutyl rubber. In the formulation of the present invention, it mainly acts as a compatibilizer and structural reinforcement, achieving the goal of lightweighting and increasing the strength of the rubber.

[0023] As a common 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 the rubber to a certain extent and improve the strength of the 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 those commonly used in the art.

[0026] The rubber composition further includes 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] 20-25 parts of anti-aging agent;

[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] 20-25 parts of accelerator zinc dialkyl dithiophosphate;

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

[0034] 30-35 parts of insoluble sulfur.

[0035] In the present invention, a variety of 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 effectively improve the wear resistance and strength;

[0036] Generally speaking, the most commonly used vulcanization accelerators are thiazoles, sulfenamides, 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 for preparing shoe soles.

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

[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, and hydrocarbon resin mixture RH-100 to a 10,000 horsepower mill and mix for 30 to 40 minutes; then add 2 / 3 of the white carbon black and mix for 50 to 70 minutes; add the remaining white carbon black and other additives except the vulcanization processing aid and mix for 90 to 110 minutes; unload, and control the unloading temperature below 130°C;

[0041] Open mill: The rubber material unloaded from the 10,000 horsepower machine is unloaded once, turned over on the turner, and then the sheet is rolled out. The temperature of the rubber material is controlled below 40℃ and placed in 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, the material is turned over for 5 to 10 minutes until the sulfur is evenly dispersed, and then the sheet is rolled out.

[0042] Vulcanization: Vulcanization mold temperature 155 ~ 160 ℃; oil pressure is 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 glass microspheres, effectively reducing the specific gravity of the sole while having 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- To reduce the impact of micron-sized hollow glass microspheres on the strength and wear resistance of the rubber composition, a hydrocarbon resin mixture RH-100 is used. This resin mixture serves as a bridge connecting the hollow glass microspheres and the main rubber, improving 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 bromobutyl rubber. In the formulation of the present invention, it mainly acts as a compatibilizer and structural reinforcement, achieving the goal of lightweighting and increasing the strength of the rubber. DETAILED DESCRIPTION

[0046] Below in conjunction with embodiments of the present invention, the present invention is clearly and completely described, in description of the present invention, it should be noted that, in the embodiment, the unrecited specific conditions person, carry out according to the condition of normal condition or manufacturer's suggestion. Reagents therefor or instrument are not recited manufacturer person, are the conventional products that can be obtained by commercial purchase. When not making special instructions, used part in the embodiments of the present invention is all weight part.

[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, and hydrocarbon resin mixture RH-100 to a 10,000 horsepower mill and mix for 35 minutes; then add 2 / 3 of the 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 mill: The rubber material unloaded from the 10,000 horsepower machine is unloaded once, turned over on the turning machine, and then the sheet is rolled out. The temperature of the rubber material is controlled below 40℃ and placed in the storage room for aging. The aging time is 5 hours. The temperature of the open mill should not exceed 80℃. After mixing and adding sulfur in the open mill, the material is turned over for 8 minutes until the sulfur is evenly dispersed, and then the sheet is rolled out.

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

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

[0052] Table 1 Recipe Unit: g

[0053]

[0054]

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

[0056] Comparative Example 5

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

[0058] Comparative Example 6

[0059] The process is substantially the same as in 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 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. As shown in Examples 1 to 3, the soles prepared from the rubber composition of the present invention can have a relative density of approximately 1.0, achieving lightweighting of the soles; their wear rate is less than 75, and their strength meets the standards.

[0069] 2. Comparative Examples 1, 2, 5, and 6 show 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 adhesive.

[0070] 3. Comparative Examples 3 and 4 show that using too much or too little isoprene rubber or high-styrene rubber will increase wear. High-styrene rubber can increase the strength of the rubber composition but reduce its elongation at break. A proper ratio of isoprene rubber and high-styrene rubber can achieve simultaneous improvements in strength and elongation at break.

[0071] 4. Comparative Example 7 shows that, unlike the applicant's prior application, thiazole and dithiophosphate accelerators are the most preferred for rubber compositions containing glass microspheres. Thiazole and sulfenamide accelerators can improve strength but have no significant effect on reducing 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 invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Equivalents to the claims are intended to be encompassed. All variations within the meaning and scope of the elements are intended to be included in the present invention.

Claims

1. A lightweight, high-strength rubber composition for shoe soles, characterized in that: It comprises the following components in parts by weight: High cis polybutadiene composite rubber VCR412 1300~1450 parts; 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; Silane coupling agent HP-669 20-25 parts; Active agent PEG-4000 20-25 parts; 20-25 parts of anti-aging agent; 20-25 parts of antiozonant; And a vulcanization processing aid, the vulcanization processing aid is composed of the following components in parts by weight: 20-25 parts of zinc dialkyl dithiophosphate accelerator; Accelerator: 6-7 parts of dibenzothiazyl disulfide; 30-35 parts of insoluble sulfur.

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

3. A lightweight and high-strength rubber sole, characterized in that: The adhesive composition is prepared according to claim 1.

4. A method for preparing a lightweight and high-strength rubber sole as claimed in claim 3, characterized in that: The steps include: Mixing: Add high-cis polybutadiene composite rubber VCR412, isoprene rubber SKI-3S, high styrene rubber HS-860, and hydrocarbon resin mixture RH-100 to a 10,000 horsepower mill and mix for 30-40 minutes; then add 2 / 3 of the 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; then discharge the material, and control the discharge temperature below 130°C; Open mill: The rubber material unloaded from the 10,000 horsepower machine is unloaded once, turned over on the turner, and then the coiled material is supercooled. The temperature of the rubber material is controlled below 40℃ and placed in 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 5-10 minutes until the sulfur is evenly dispersed, and then coil 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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