CN118374068A - Preparation method and application of diatomite and zinc oxide composite high-density rubber material - Google Patents

Abstract

The invention provides a preparation method and application of a diatomite and zinc oxide composite high-density rubber material, and belongs to the technical field of solid adsorbent composition materials. First, a rubber mother liquor is prepared according to a certain ratio of natural rubber and epoxy natural rubber. Then, zinc oxide and diatomite in a certain proportion are added and mixed with the rubber mother solution, and the mixture is heated and stirred to prepare the zinc oxide and diatomite rubber material. Then adding N-cyclohexyl-2-benzothiazole-sulfonamide, diphenyl guanidine and sulfur, mixing with zinc oxide and diatomite rubber material, grinding, heating and stirring to prepare the zinc oxide and diatomite composite rubber solution. Finally, the zinc oxide and diatomite composite high-density rubber solution is injected into an injection molding machine, and a target mold is selected for molding. Meanwhile, the rubber material is used as a rubber material, can enhance the elasticity and wear resistance of the rubber material, is a cost-effective and high-performance choice, and can well exert the elasticity and skid resistance of the tire when applied to the tire.

Description

Preparation method and application of diatomite and zinc oxide composite high-density rubber material

Technical Field

The invention belongs to the technical field of solid filler composite materials, and in particular relates to a preparation method and application of a diatomaceous earth and zinc oxide composite high-density rubber material.

Background technique

Due to its excellent properties, natural rubber has been widely used in many fields of national economic and social development. However, pure natural rubber usually needs to be added with reinforcing fillers to make it highly elastic and strong due to its low strength and modulus. In addition to its excellent elasticity, natural rubber also exhibits viscoelasticity. The dynamic heat generation characteristics of rubber are related to its own viscoelasticity. After vulcanization, the macromolecular chains form a cross-linked network, so that the relative positions between the molecular chains in the rubber and between the molecular chains and the filling particles do not change in static state. When subjected to periodic deformation, the rubber material is subjected to dynamic alternating stress, and the rubber molecular chains and filling particles move relative to each other under the action of external forces, so that the molecular chains in the rubber, the molecular chains and the filling separation, and the filling particles slide relative to each other, generating heat. And rubber, like most polymers, is a poor conductor of heat, so it cannot quickly transfer the heat inside the rubber to the outside world, accelerates the aging of the rubber, and leads to a decrease in the safety and life of rubber products. Therefore, improving the dispersibility of fillers in rubber and enhancing the interface interaction between fillers and rubber matrix can effectively reduce the dynamic heat accumulation of rubber products and increase the service life of products.

The Chinese invention patent with application number CN202010190290.6 discloses a method for preparing a graphene oxide reinforced styrene-butadiene rubber material, comprising the following steps: step 1, ultrasonically dispersing 0.1 to 0.8 parts of casein in an ammonia solution to obtain an ammonia solution of casein, pre-treating 1.5 to 3.0 parts of graphene oxide and adding them to an aqueous chitosan solution with a concentration of 8 mg/ml to 12 mg/ml, stirring and mixing, adding the ammonia solution of casein, ultrasonically dispersing for 5 minutes, and obtaining a casein-graphene oxide mixed solution; step 2, adding the casein-graphene oxide mixed solution obtained in step 1 to 20 to 60 parts of nitrile latex, stirring and mixing evenly, adding a calcium chloride solution with a concentration of 8wt% to 14wt%, mixing and stirring, and standing for 20 minutes. The modified nitrile latex is obtained by drying; step 3, 100 parts of styrene-butadiene rubber are put into an open mill for plastication to obtain plasticized rubber; step 4, water, anhydrous ethanol and a silane coupling agent are mixed at 50° C. to 65° C. for 3 minutes to obtain a mixed solution, the mixed solution is evenly sprayed on the surface of 2.5 parts to 6.5 parts of boron nitride whiskers, and then dried to obtain modified boron nitride whiskers; step 5, the modified nitrile latex obtained in step 2, the plasticized rubber obtained in step 3 and the modified boron nitride whiskers obtained in step 4 are put into an internal mixer, and the mixture is mixed for 3 minutes, and 1.8 parts to 3.6 parts of nano-silicon dioxide, 1.2 parts to 3.5 parts of paraffin wax, 0.8 parts to 1.5 parts of zinc oxide and 0.3 parts to 1.5 parts of an antioxidant are added, and the mixture is mixed and molded to obtain a graphene oxide reinforced styrene-butadiene rubber material.

The limitation of this technology is that although graphene fillers can increase the dispersion stress of rubber molecules, prevent molecular chain breakage, and enhance the strength of rubber, their size is limited and their dispersion in the matrix is limited, resulting in low elasticity of the rubber.

The Chinese invention patent with application number CN202010190290.6 discloses a modified diatomite and its application in rubber materials, comprising the following steps: step 1, take 20-30 parts of diatomite, add 20-30 parts of a mixed acid of hydrofluoric acid and sulfuric acid and 30-40 parts of deionized water, stir for 2-5 minutes, put it into an ultrasonic instrument, and ultrasonically treat it at 200-300W for 30-60 minutes; step 2, transfer it to a muffle furnace and roast it at a temperature of 400-500℃ for 30-60 minutes; step 3, take it out after natural cooling to obtain a modified diatomite. soil; step 4, stirring and dissolving ferric chloride, aluminum chloride and deionized water, wherein the molar ratio of [Fe3+]/([Fe3+]+[Al3+]) is 0.5-0.7; step 5, placing in a 70°C water bath, slowly adding NaOH solution under constant stirring to adjust its alkalinity to 1.5, aging at room temperature for 2 days to obtain liquid A; step 6, mixing the primary modified diatomaceous earth and a KCl solution with a concentration of 1.0-2.0 mol/L, and shaking at 60°C for 2-3 hours; step 7, centrifuging, removing the supernatant, washing with deionized water 2-3 times, and placing in an oven at Dry at 100-105°C, grind, and sieve to obtain secondary modified diatomite; Step 8, add deionized water to make a 3wt% suspension, slowly drop 30-40 parts of liquid A, and stir, and continue to oscillate for 2-3h after the dropwise addition is completed; Step 9, react at a constant temperature of 50-90°C for 12-36h, discard the supernatant, wash with deionized water 2-3 times, centrifuge, and air-dry at room temperature; Step 10, age at a constant temperature of 300-600°C for 1-3h to obtain tertiary modified diatomite; Step 11, evenly spread the tertiary modified diatomite on a low-temperature plasma treatment On the ground electrode in the device, treat for 10-15 minutes under the conditions of power frequency of 10-15kHz, working voltage of 20kV, and discharge power of 70-80W to obtain four-time modified diatomite; step 12, place it in a constant temperature water bath at 90°C, stir and preheat at a speed of 250-300r/min, add 1wt%-2wt% stearic acid anhydrous ethanol solution dropwise, after adding, increase the stirring speed to 1500r/min, and stir the reaction for 60min; step 13, centrifuge, put it in a drying oven and dry it at a temperature of 60-70°C to obtain modified diatomite.

The limitations of this technology are: diatomaceous earth filler has high temperature resistance and excellent thermal conductivity, which can improve the wear resistance and thermal conductivity of rubber, but the rubber elasticity is not high.

Summary of the invention

In view of the problem that the above-mentioned technology cannot obtain rubber with high elasticity, the first aspect of the present invention provides a method for preparing a high-density rubber material composited with diatomaceous earth and zinc oxide.

Taking natural rubber as a carrier, the surface of the natural rubber is loaded with diatomaceous earth and zinc oxide, and the zinc oxide is loaded on the diatomaceous earth;

The preparation method comprises the following steps:

S1, crushing and calcining the original diatomite, and cooling to obtain carbonized diatomite;

S2, mixing carbonized diatomaceous earth, raw rubber, stearic acid, zinc oxide, sulfur powder and a vulcanization accelerator, heating, and cooling to obtain modified diatomaceous earth;

S3, adding natural rubber and epoxidized natural rubber with different contents into a mixer, heating, stirring and mixing to obtain a rubber mother liquor;

S4, adding the rubber mother liquid obtained in S3 to the modified diatomaceous earth, calcium stearate, zinc oxide, and bio-resin obtained in S2, heating, stirring, mixing, and extruding to obtain a zinc oxide/diatomaceous earth rubber material;

S5, adding N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine, and sulfur to the zinc oxide/diatomaceous earth rubber material obtained in S4, grinding, heating, and mixing to obtain a zinc oxide/diatomaceous earth composite rubber solution;

S6, placing the zinc oxide/diatomaceous earth composite rubber solution obtained in S5 into a mold, cooling and molding, and obtaining a diatomaceous earth and zinc oxide composite high-density rubber material.

Preferably, in S2, the mass ratio of carbonized diatomaceous earth, raw rubber, stearic acid, zinc oxide, sulfur powder and vulcanization accelerator is 100:100:100:15:300:10, and the mixing temperature is 140°C.

Preferably, S4 is specifically:

S41, leaving the rubber mother solution to stand for 12 hours at a temperature of 16° C. to obtain a rubber gel;

S42, adding modified diatomaceous earth, calcium stearate, zinc oxide and bio-resin to the rubber gel obtained in S41 to obtain a mixed solution, stirring and mixing at a temperature of 110° C. and a rotation speed of 60 rpm for 8 minutes, and extruding to obtain a zinc oxide/diatomaceous earth rubber material.

Preferably, S5 is specifically:

S51, heating, extruding, and shearing the zinc oxide/diatomaceous earth rubber material to obtain zinc oxide/diatomaceous earth rubber particles with a diameter of 3 mm;

S52, adding N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine, and sulfur to the zinc oxide/diatomaceous earth rubber particles obtained in S51, grinding, mixing, and heating to obtain a zinc oxide/diatomaceous earth rubber composite solution.

Preferably, in S3, the volume mixing ratio of natural rubber and epoxidized natural rubber is 50 mL:50 mL, the oxygen concentration in the epoxidized natural rubber is 25 mol% and 50 mol%, and the solution is stirred at a temperature of 110°C, at a speed of 60 rpm, and for 8 minutes.

Preferably, in S42, the volume of the rubber gel is 100 mL, the mass ratio of modified diatomaceous earth, calcium stearate, zinc oxide and bio-resin is 60 g:3 g:2 g:2 g, the heating temperature is 110° C., the stirring speed is 60 rpm, and the stirring time is 8 minutes.

Preferably, in S51, the mass of the zinc oxide/diatomaceous earth rubber material is 100 g, the heating temperature is 100° C., the extrusion speed is 15 g/min, and the diameter of the zinc oxide/diatomaceous earth rubber particles is 3 mm.

Preferably, in S52, the mass of the zinc oxide/diatomaceous earth rubber material is 100 g, the mass ratio of N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine and sulfur is 1.2 g:1.5 g:2 g, the grinding speed is 70 rpm, the heating temperature is 110°C, the stirring speed is 60 rpm, and the stirring time is 4 minutes.

Preferably, in S6, the resistance force of the zinc oxide/diatomaceous earth composite rubber solution injection molding is 245166.3N, the cavity filling time is 1s, and the cavity cooling time is 15s.

The second aspect of the present invention provides an application of a diatomaceous earth and zinc oxide composite high-density rubber material prepared by the preparation method described in the first aspect: the composite high-density rubber material is used as a tire material to maintain the high elasticity of the rubber material.

Compared with the prior art, the present invention has the following beneficial effects:

(1) Provided is a diatomite and zinc oxide composite high-density rubber material, with natural rubber as a carrier and zinc oxide/diatomite distributed on the rubber surface. In the micro-powder sorting process, the modified diatomite prepared in the present invention uses a self-developed micro-powder pulse separation device to obtain 325 mesh full-pass powder through high-speed centrifugal sorting, so that the prepared modified diatomite has higher precision and less impurities. The modified diatomite has a porous structure and can be used as a polymer material for filling natural rubber to improve the solidification of natural rubber; the nano zinc oxide particles are conducive to promoting the efficient solidification of natural rubber in the sulfur crosslinking process, while reducing the heat accumulation of the rubber material and improving the wear resistance of the rubber; the natural rubber has excellent properties such as resilience, insulation, water-proof and plasticity, and its macromolecular chain is mainly composed of polyisoolefins, which can also have the properties of oil resistance, acid resistance, alkali resistance, heat resistance, cold resistance, pressure resistance and wear resistance after proper treatment. The diatomite and zinc oxide composite rubber material formed by the composite of these three materials, the blending of zinc oxide, diatomite and natural rubber promotes rubber solidification and maintains the good elasticity of the composite material; and the composite material improves the elasticity and wear resistance of the composite rubber tire by increasing rubber solidification and elasticity, so that the wet grip of the composite rubber tire is shown to be larger. In addition, in the diatomite and zinc oxide composite rubber material of the present invention, natural rubber is used as the main material, and the amount of diatomite and zinc oxide is small. Since the price of zinc oxide is very low, the cost of the composite material is relatively low, and it is economical and practical. Therefore, the diatomite and zinc oxide composite rubber material of the present invention has the advantages of low cost, stable structure, good elasticity, high wear resistance, wide application range, etc., and has high application value and good application prospects;

(2) The present invention also provides a method for preparing a diatomaceous earth and zinc oxide composite high-density rubber material, using natural rubber and epoxy natural rubber with different oxygen contents as raw materials to prepare a rubber mother liquor; while adding diatomaceous earth and zinc oxide, a bio-resin is also introduced, mixed, extruded, and cut into microsphere particles; N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine, and sulfur are added, ground and mixed, and injection molded to obtain a diatomaceous earth and zinc oxide composite rubber material. The bio-resin has high polarity and low aromaticity, and can be used as a plasticizer to soften uncured rubber compounds. In addition, the bio-resin is used in small amounts, is easy to obtain, and is economical in price, and the preparation operation process is also relatively simple. The preparation method of the present invention has the advantages of simple process, convenient operation, and low cost, and can achieve large-scale preparation and is suitable for industrial use;

(3) The diatomite and zinc oxide composite high-density rubber material of the present invention can be used to prepare automobile tires. The results show that compared with traditional rubber materials, the diatomite and zinc oxide composite rubber material of the present invention reduces the rolling resistance of the diatomite and zinc oxide composite rubber tire by 4% and improves the wet grip performance by 33%. The storage modulus value of the diatomite and zinc oxide composite rubber tire is twice that of the traditional composite rubber material, and its enriched silica is more evenly dispersed in natural rubber and epoxy rubber, showing the superiority of the diatomite and zinc oxide composite rubber in tire applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the overall process of the preparation method of the present invention.

Figure 2 is a physical picture of modified diatomite.

FIG. 3 is a comparison diagram of stress-strain curves of conventional rubber materials and the composite high-density rubber material of the present invention.

FIG. 4 is a comparison diagram of the curing curve (a) and the derivative curing curve (b) of a conventional rubber material and the composite high-density rubber material of the present invention.

FIG. 5 is a comparison diagram of the storage modulus and temperature curve (a) and the loss tangent and temperature curve (b) of a conventional rubber material and the composite high-density rubber material of the present invention.

Detailed ways

The present invention is further described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Embodiment 1:

Natural rubber has excellent resilience, insulation, water-proof and plasticity. Its macromolecular chain is mainly composed of polyisocyanate, which can be oil-resistant, acid-resistant, alkali-resistant, heat-resistant, cold-resistant, pressure-resistant and wear-resistant after proper treatment. Silicon-based diatomaceous earth is often used as a material to fill natural rubber due to its unique void structure, which can improve the curing of natural rubber. Nano zinc oxide particles are beneficial to promote the efficient curing of natural rubber in the sulfur cross-linking process, while reducing the heat accumulation of rubber materials and improving the wear resistance of rubber. Therefore, the combined use of diatomaceous earth and nano zinc oxide particles in rubber will enhance the application and popularization of rubber materials in production and life.

In order to improve the surface performance of diatomite, the present invention provides a preparation method of modified diatomite.

The technology includes the following steps: firstly, the original diatomite is crushed to less than 200 meshes, then calcined at high temperature, isolated from air for heat preservation, and cooled in the furnace to form carbonized diatomite. Then, the carbonized diatomite, raw rubber, stearic acid, zinc oxide, sulfur powder and vulcanization accelerator are mixed at a mass ratio of 100:100:100:15:300:10 at a certain temperature, and after cooling, they are molded in a flat vulcanizer to prepare modified diatomite.

In order to improve the elasticity and wear resistance of rubber materials, the present invention proposes a preparation method and application of a modified diatomite and zinc oxide composite high-density rubber material. The zinc oxide/diatomite rubber composite high-density material uses natural rubber as a carrier, and diatomite/zinc oxide is loaded on the surface of the natural rubber; the zinc oxide/diatomite composite material includes zinc oxide and diatomite, and zinc oxide is loaded on the diatomite; the mass volume ratio of zinc oxide, diatomite and natural rubber is 1:60:100.

The technology includes the following key steps, as shown in Figure 1: First, prepare modified diatomaceous earth. Then, prepare a rubber mother liquor according to a certain ratio of natural rubber and epoxy rubber. Subsequently, in order to improve its performance, add modified diatomaceous earth, calcium stearate, zinc oxide, and bio-resin, and heat, stir and mix them with the rubber mother liquor in a reactor to prepare a zinc oxide/diatomaceous earth rubber material. Subsequently, add N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine, and sulfur, grind, heat, mix, inject into an injection molding machine, select the target mold, and form.

Preparation of modified diatomaceous earth:

The original diatomite is crushed to less than 200 meshes, calcined at high temperature, the calcination temperature is 100℃, isolated from air for heat preservation, and cooled with the furnace to make carbonized diatomite. Carbonized diatomite, raw rubber, stearic acid, zinc oxide, sulfur powder and vulcanization accelerator are mixed at a mass ratio of 100:100:100:15:300:10 at a temperature of 140℃, and formed in a flat vulcanizer after cooling. The variable program control program is used to fully automatically control the exhaust valve and pulse valve to modify the diatomite, and high-precision modified diatomite is prepared, as shown in Figure 2.

Preparation of rubber mother liquor:

Natural rubber and epoxidized natural rubber were added into a reactor at a volume ratio of 50 mL:50 mL, and stirred for 8 minutes at a temperature of 110° C. and a rotation speed of 60 rpm/min under the action of a stirrer in the reactor to obtain a rubber mother liquor.

Preparation of zinc oxide/diatomaceous earth rubber material:

The rubber mother liquor was allowed to stand at 16°C for 12 hours to obtain a rubber gel. The modified diatomaceous earth, calcium stearate, zinc oxide, and bio-resin were mixed with the rubber gel at a mass ratio of 60g:3g:2g:2g:100mL for 8 minutes, and stirred at 110°C and 60rpm to obtain a zinc oxide/diatomaceous earth zinc oxide/diatomaceous earth rubber material.

Preparation of zinc oxide/diatomaceous earth composite rubber solution:

The zinc oxide/diatomaceous earth rubber material is heated at a temperature of 100°C, extruded, and sheared to obtain zinc oxide/diatomaceous earth rubber particles with a diameter of 3 mm; N-cyclohexyl-2-benzothiazole-sulfonamide, diphenylguanidine, sulfur and zinc oxide/diatomaceous earth rubber particles are mixed according to a mass ratio of 1.2g:1.5g:2g:100g, the grinding speed is 70rpm, the temperature is 110°C, the rotation speed is 60rpm, and the stirring is carried out for 4 minutes to obtain a zinc oxide/diatomaceous earth rubber composite solution.

Preparation of diatomaceous earth and zinc oxide composite high-density rubber material:

The zinc oxide/diatomaceous earth rubber composite solution was added into the injection molding machine, the target mold was selected, and a resistance force of 245166.3 Newtons (i.e., 25 tons) was applied during the injection molding process. The cavity filling and cooling times were 1 s and 15 s, respectively, to obtain a diatomaceous earth and zinc oxide composite high-density rubber material.

Figure 3 shows the stress-strain curves of the high-density rubber materials composited with zinc oxide and diatomite. The physical properties of the high-density rubber materials composited with zinc oxide and diatomite in terms of tensile strength, elongation at break, 300% strain modulus and hardness were significantly improved in most cases (Table 1). This indicates that during the vulcanization process, the combination of nano zinc oxide with the bio-resin resulted in an increase in the cross-linking degree and cross-linking density of the elastomer. The bio-resin formed stronger hydrogen bonds with the rubber-silica surface. The multifunctional and abundant aromatic hydroxyl groups provided sites for hydrogen bonding to promote greater silica dispersion in the blend of natural rubber and epoxidized natural rubber.

Embodiment 2:

The diatomaceous earth and zinc oxide composite high-density rubber material prepared by the preparation method of Example 1 is used as a tire material to maintain the high elasticity of the rubber material.

1. Elastic compression test

The zinc oxide/diatomaceous earth composite high-density rubber material was prepared into a tire. The zinc oxide/diatomaceous earth composite high-density rubber tire was cut into a shape of 10×10 cm in length and width, placed in an oscillating disc rheometer, and heated at 150°C for 30 minutes to determine the optimal curing time and baking time of the zinc oxide and diatomaceous earth composite high-density rubber material.

The rubber material test without zinc oxide was used as the blank control group, and the zinc oxide and diatomaceous earth composite high-density rubber material test with zinc oxide added was used as the experimental group.

Figures a and b in Figure 4 describe the elastic properties of zinc oxide and diatomite composite high-density rubber tires. As shown in Table 1, the incorporation of nano zinc oxide increases the modulus of the zinc oxide/diatomite composite rubber when strained without affecting the elastic time of the rubber. Nano zinc oxide with a large surface area can greatly increase the maximum contact with diphenylguanidine/n-cyclohexyl-2-benzothiazole-sulfonamide, sulfur, etc. during vulcanization. This phenomenon makes nano zinc oxide an efficient activator for sulfur-crosslinkable rubber. In addition, when bio-resin is used to couple with nano zinc oxide, in most cases, the maximum rheometer torque value has a marginal increase. This may be due to the high polar compatibility between polar bio-resins in the blend of natural rubber and epoxy rubber. In general, the curing characteristics of zinc oxide and diatomite composite high-density rubber materials seem to be significantly affected by the addition of bio-resin and nano zinc oxide.

Table 1 Physical, mechanical and rheological properties of traditional/zinc oxide and diatomaceous earth composite high-density rubber materials

2. Rolling resistance test

The zinc oxide/diatomaceous earth composite high-density rubber material was prepared into a tire. The zinc oxide/diatomaceous earth composite high-density rubber tire was cut into a shape of 10×10 cm in length and width, and placed in a temperature of -100℃~100℃, a tension of 0.1%, 10Hz, and a heating rate mode of 3℃/min for dynamic analysis. The dynamic strain amplitude of 0.56%~100% was measured at a constant frequency of 10Hz.

The rubber material test without zinc oxide was used as the blank control group, and the zinc oxide and diatomaceous earth composite high-density rubber material test with zinc oxide added was used as the experimental group.

Figure 5a shows the storage modulus versus temperature curve of conventional/zinc oxide and diatomite composite high-density rubber materials. In order to determine the impact of zinc oxide and diatomite composite high-density rubber on tire applications in detail, the results of rolling resistance at 60°C and wet grip at 0°C were considered respectively. Rolling resistance represents an opposite trend to the wet grip properties. Obviously, lower hysteresis will be conducive to lower rolling resistance. Zinc oxide and diatomite composite high-density rubber shows a similar trend to composite rubber in terms of dynamic mechanical properties. Bioresins easily react with rubber or fillers and produce additional crosslinks. This leads to the formation of a stronger immobilized rubber shell around the silica particles and the release of more rubber from the void space of the silica aggregates. The elastic properties of the compound are improved by reducing hysteresis and show the lowest value in zinc oxide and diatomite composite rubber. The results show that the rolling resistance performance is reduced by 4% and the wet grip performance is improved by 33% compared with conventional rubber materials. Figure 5b shows the temperature dependence of the storage modulus, which also refers to the material wear curve. The storage modulus values of all compounds decreased significantly near the transition zone from -50°C to 10°C. This sharp drop in storage modulus is due to the increased mobility of the rubber segments with increasing temperature. The storage modulus values of the composites in the rubber state (25-80°C) can be used to evaluate the interaction between fillers and rubber. The storage modulus values of the green composites are almost twice that of the conventional composite rubber materials. This effect may be due to the presence of bio-resin and nano-zinc oxide-enriched silica dispersion in natural rubber and epoxy rubber.

The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Although the above describes the specific implementation methods of the present invention, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims (9)

1. A preparation method of a diatomite and zinc oxide composite high-density rubber material is characterized by comprising the following steps:

Taking natural rubber as a carrier, wherein diatomite and zinc oxide are loaded on the surface of the natural rubber, and the zinc oxide is loaded on the diatomite;

The preparation method comprises the following steps:

s1, crushing and calcining raw diatomite, and cooling to obtain carbonized diatomite;

s2, mixing carbonized diatomite, raw rubber, stearic acid, zinc oxide, sulfur powder and a vulcanization accelerator, heating and cooling to obtain modified diatomite;

s3, adding the natural rubber and the epoxidized natural rubber with different contents into a stirrer, heating, stirring and mixing to obtain a rubber mother solution;

S4, adding the modified diatomite, calcium stearate, zinc oxide and biological resin obtained in the step S2 into the rubber mother solution obtained in the step S3, heating, stirring, mixing and extruding to obtain a zinc oxide/diatomite rubber material;

s5, adding the zinc oxide/diatomite rubber material obtained in the step S4 into N-cyclohexyl-2-benzothiazole-sulfonamide, diphenyl guanidine and sulfur, grinding, heating and mixing to obtain a zinc oxide/diatomite composite rubber solution;

S6, placing the zinc oxide/diatomite composite rubber solution obtained in the step 5 in a die, and cooling and forming to obtain the diatomite and zinc oxide composite high-density rubber material.

2. The method for preparing the diatomite and zinc oxide composite high-density rubber material according to claim 1, wherein the S4 specifically comprises:

s41, standing the rubber mother liquor for 12 hours at the temperature of 16 ℃ to obtain rubber gel;

s42, adding modified diatomite, calcium stearate, zinc oxide and biological resin into the rubber gel obtained in the step S41 to obtain a mixed solution, stirring and mixing for 8 minutes at the temperature of 110 ℃ and the rotating speed of 60rpm, and extruding to obtain the zinc oxide/diatomite rubber material.

3. The method for preparing the diatomite and zinc oxide composite high-density rubber material according to claim 1, wherein the step S5 is specifically:

S51, heating, extruding and shearing a zinc oxide/diatomite rubber material to obtain zinc oxide/diatomite rubber particles with the diameter of 3 mm;

s52, adding the zinc oxide/diatomite rubber particles obtained in the step S51 into N-cyclohexyl-2-benzothiazole-sulfonamide, diphenyl guanidine and sulfur, grinding, mixing and heating to obtain the zinc oxide/diatomite rubber composite solution.

4. The method for preparing the diatomite and zinc oxide composite high-density rubber material as set forth in claim 1, wherein the method comprises the following steps: in the S3, the volume mixing ratio of the natural rubber to the epoxidized natural rubber is 50mL:50mL of the epoxidized natural rubber had an oxygen content of 25 mol% and 50 mol%, and the solution was stirred at 110℃for 8 minutes at 60 rpm.

5. The method for preparing the diatomite and zinc oxide composite high-density rubber material as set forth in claim 2, wherein the method comprises the following steps: in the S42, the volume of the rubber gel is 100mL, and the mass ratio of the modified diatomite, the calcium stearate, the zinc oxide and the biological resin is 60g:3g:2g:2g, heating temperature 110 ℃, stirring speed 60rpm, stirring time 8 minutes.

6. The method for preparing the diatomite and zinc oxide composite high-density rubber material as set forth in claim 3, wherein the method comprises the following steps: in S51, the mass of the zinc oxide/diatomite rubber material is 100g, the heating temperature is 100 ℃, the extrusion speed is 15 g/min, and the particle diameter of the zinc oxide/diatomite rubber material is 3mm.

7. The method for preparing the diatomite and zinc oxide composite high-density rubber material as set forth in claim 3, wherein the method comprises the following steps: in the S52, the mass ratio of the zinc oxide to the diatomite rubber material is 100g, and the mass ratio of the N-cyclohexyl-2-benzothiazole-sulfonamide to the diphenyl guanidine to the sulfur is 1.2g:1.5g:2g, a grinding speed of 70rpm, a heating temperature of 110 ℃, a stirring speed of 60rpm and a stirring time of 4 minutes.

8. The method for preparing the diatomite and zinc oxide composite high-density rubber material as set forth in claim 1, wherein the method comprises the following steps: in the step S6, the blocking force of injection molding of the zinc oxide/diatomite composite rubber solution is 245166.3N, the cavity filling time is 1S, and the cavity cooling time is 15S.

9. Use of the diatomite and zinc oxide composite high-density rubber material prepared by the preparation method according to any one of claims 1 to 8, characterized in that: is used as a tire material to maintain the elasticity and wear resistance of the rubber material.