Method for manufacturing rubber from waste rubber

Abstract

The invention discloses a method for manufacturing rubber from waste rubber, and belongs to the technical field of rubber production. Waste rubber is recycled through the steps of material preparation, smashing, internal mixing, secondary internal mixing, forming and the like, the emulsibility and integration of the rubber are thoroughly stimulated through the internal mixing technology, the physical performance of the rubber is effectively improved, after the rubber waste is modified, waste components are activated again and then enter a vulcanization state again through secondary internal mixing, and the rubber waste is recycled. Therefore, the storage time of the rubber can be prolonged, the cost can be effectively saved, the service life of the rubber is prolonged, and the safety is also improved.

Description

Technical Field

[0001] This invention relates to the field of rubber technology, and more specifically to a method for manufacturing rubber from waste rubber. Background Technology

[0002] Rubber is commonly used in the production of wheels, conveyor belts, structural components, shoe materials, and other products. The annual consumption of rubber is also staggering. How to properly dispose of waste rubber has become an urgent problem to be solved. Turning waste into treasure is the mainstream method of rubber treatment. Therefore, rubber production technology also becomes very important. Inappropriate reprocessing may not meet the conditions for the use of rubber and will waste human and material resources.

[0003] Existing rubber products (including rubber shoe soles) do not have a formulation technology that adds waste rubber to the raw materials with a grinding ratio exceeding 50%, nor do they have a technology for direct modification of rubber through vulcanization (dead material). They are all made with traditional natural rubber and synthetic rubber (i.e., styrene-butadiene rubber and cis-butadiene rubber, abbreviated as SBR and BR) as the main components. This type of rubber has a low proportion of waste rubber added, high cost, and great waste of resources. Moreover, the finished rubber products have a short storage time and are prone to aging. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned technical problems and provide a method for manufacturing rubber from waste rubber. The rubber prepared by this method can be used to make shoe sole rubber, saving costs. Moreover, the produced rubber is easy to store and does not age easily.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for manufacturing rubber from waste rubber, comprising the following steps:

[0006] Step 1: Material preparation: Clean the recycled waste rubber scraps and dry them at 40-50℃ to obtain dried waste rubber scraps.

[0007] Step 2, Crushing: Crush the dried waste rubber scraps obtained in Step 1 into granules to obtain waste rubber granules;

[0008] Step 3, Internal mixing: According to the weight parts, mix 60-70 parts of waste rubber granules obtained in Step 2, 20-30 parts of emulsifier, 5-10 parts of fumed silica, 3-5 parts of vulcanization accelerator and 7-10 parts of softening oil and add them to the internal mixer for internal mixing. When the temperature of the internal mixer reaches 100-110℃, the internal mixing raw material can be obtained.

[0009] Step 4, Secondary mixing: After the raw material from the mixing process in Step 3 has cooled, add 3-5 parts of vulcanization accelerator to 100 parts of the raw material obtained in Step 3 by weight, mix and then mix again. The temperature of the mixing mill is controlled at 80℃ to obtain the secondary mixed rubber compound.

[0010] Step 5, Molding: The secondary mixer obtained in Step 4 is conveyed to a granulator via a conveyor belt to granulate or sheet the secondary mixer compound, thus obtaining the rubber raw material.

[0011] Preferably, in the method for manufacturing rubber from waste rubber of the present invention, the waste rubber particles in step two are sieved through a 100-mesh sieve.

[0012] Preferably, in the method for manufacturing rubber from waste rubber of the present invention, the vulcanization accelerator in step three is one of N-tert-butyl-2-benzothiazole sulfenamide (NS), N-cyclohexyl-2-benzothiazole sulfenamide (CZ), N,N, dicyclohexyl-2-benzothiazole sulfenamide (DZ), and N-oxodiethyl-2-benzothiazole sulfenamide (NOBS).

[0013] Preferably, in the method for manufacturing rubber from waste rubber of the present invention, the softening oil in step three is one of vegetable oil, mineral oil or rubber oil.

[0014] Preferably, in the method for manufacturing rubber from waste rubber of the present invention, the mixing raw material described in step four is cooled to 60-80°C.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention recycles waste rubber through material preparation, crushing, mixing, secondary mixing, and molding. The mixing process thoroughly stimulates the emulsification and blending properties of the rubber, effectively improving its physical properties. The secondary mixing process modifies the waste rubber, and the waste components are reactivated and re-enter the vulcanization state, thereby increasing the shelf life of the rubber, effectively saving costs, extending the service life of the rubber, and improving safety. Detailed Implementation

[0016] The present invention will be further described below with reference to the embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0017] Example 1

[0018] A method for manufacturing rubber from waste rubber includes the following steps:

[0019] Step 1: Material preparation: Clean the recycled waste rubber scraps and dry them at 45℃ to obtain dried waste rubber scraps.

[0020] Step 2, Crushing: The dried waste rubber scraps obtained in Step 1 are crushed into granules to obtain waste rubber granules. The particle size of the waste rubber granules passes through a 100-mesh sieve.

[0021] Step 3, Internal mixing: According to the weight parts, 62 parts of waste rubber granules obtained in Step 2, 20 parts of emulsifier, 7 parts of fumed silica, 3 parts of N-tert-butyl-2-benzothiazole sulfenamide (NS) and 8 parts of mineral oil are mixed and added to the internal mixer for internal mixing. When the temperature of the internal mixer reaches 100℃, the internal mixing raw material can be obtained.

[0022] Step 4, Secondary mixing: After the raw material from the mixing process in Step 3 has cooled to 65°C, add 3 parts of accelerator to the 100 parts of raw material obtained in Step 3 by weight, mix and then mix again. The temperature of the mixing mill is controlled at 80°C to obtain the secondary mixed rubber compound.

[0023] Step 5, Molding: The secondary mixer obtained in Step 4 is conveyed to a granulator via a conveyor belt to granulate or sheet the secondary mixer compound, thus obtaining the rubber raw material.

[0024] Example 2

[0025] A method for manufacturing rubber from waste rubber includes the following steps:

[0026] Step 1: Material preparation: Clean the recycled waste rubber scraps and dry them at 50℃ to obtain dried waste rubber scraps.

[0027] Step 2, Crushing: The dried waste rubber scraps obtained in Step 1 are crushed into granules to obtain waste rubber granules. The particle size of the waste rubber granules passes through a 100-mesh sieve.

[0028] Step 3, Internal mixing: According to the weight parts, mix 65 parts of waste rubber granules obtained in Step 2, 20 parts of emulsifier, 5 parts of fumed silica, 3 parts of N-tert-butyl-2-benzothiazole sulfenamide (NS) and 7 parts of mineral oil and add them to the internal mixer for internal mixing. When the temperature of the internal mixer reaches 105℃, the internal mixing raw material can be obtained.

[0029] Step 4, Secondary mixing: After the raw material from the mixing process in Step 3 has cooled to 70°C, add 5 parts of accelerator to the 100 parts of raw material obtained in Step 3 by weight, mix and then mix again. The temperature of the mixing mill is controlled at 80°C to obtain the secondary mixed rubber compound.

[0030] Step 5, Molding: The secondary mixer obtained in Step 4 is conveyed to a granulator via a conveyor belt to granulate or sheet the secondary mixer compound, thus obtaining the rubber raw material.

[0031] Compare with Example 1

[0032] The difference from Example 1 is that the vulcanization accelerator in step three is N-cyclohexyl-2-benzothiazole sulfenamide (CZ), as detailed below:

[0033] A method for manufacturing rubber from waste rubber includes the following steps:

[0034] Step 1: Material preparation: Clean the recycled waste rubber scraps and dry them at 45℃ to obtain dried waste rubber scraps.

[0035] Step 2, Crushing: The dried waste rubber scraps obtained in Step 1 are crushed into granules to obtain waste rubber granules. The particle size of the waste rubber granules passes through a 100-mesh sieve.

[0036] Step 3, Internal mixing: According to the weight parts, 62 parts of waste rubber granules obtained in Step 2, 20 parts of emulsifier, 7 parts of fumed silica, 3 parts of N-cyclohexyl-2-benzothiazole sulfenamide (CZ) and 8 parts of mineral oil are mixed and added to the internal mixer for internal mixing. When the temperature of the internal mixer reaches 100℃, the internal mixing raw material can be obtained.

[0037] Step 4, Secondary mixing: After the raw material from the mixing process in Step 3 has cooled to 65°C, add 3 parts of accelerator to the 100 parts of raw material obtained in Step 3 by weight, mix and then mix again. The temperature of the mixing mill is controlled at 80°C to obtain the secondary mixed rubber compound.

[0038] Step 5, Molding: The secondary mixer obtained in Step 4 is conveyed to a granulator via a conveyor belt to granulate or sheet the secondary mixer compound, thus obtaining the rubber raw material.

[0039] Compare with Example 2

[0040] The difference from Example 1 is that the softening oil in step three is a vegetable oil, as detailed below:

[0041] A method for manufacturing rubber from waste rubber includes the following steps:

[0042] Step 1: Material preparation: Clean the recycled waste rubber scraps and dry them at 50℃ to obtain dried waste rubber scraps.

[0043] Step 2, Crushing: The dried waste rubber scraps obtained in Step 1 are crushed into granules to obtain waste rubber granules. The particle size of the waste rubber granules passes through a 100-mesh sieve.

[0044] Step 3, Internal mixing: According to the weight proportions, mix 65 parts of waste rubber granules obtained in Step 2, 20 parts of emulsifier, 5 parts of fumed silica, 3 parts of N-tert-butyl-2-benzothiazole sulfenamide (NS) and 7 parts of vegetable oil and add them to the internal mixer for internal mixing. When the temperature of the internal mixer reaches 105℃, the internal mixing raw material can be obtained.

[0045] Step 4, Secondary mixing: After the raw material from the mixing process in Step 3 has cooled to 70°C, add 5 parts of accelerator to the 100 parts of raw material obtained in Step 3 by weight, mix and then mix again. The temperature of the mixing mill is controlled at 80°C to obtain the secondary mixed rubber compound.

[0046] Step 5, Molding: The secondary mixer obtained in Step 4 is conveyed to a granulator via a conveyor belt to granulate or sheet the secondary mixer compound, thus obtaining the rubber raw material.

[0047] The above embodiments are merely preferred embodiments of the present invention and should not be used to limit the scope of protection of the present invention. Any modifications or refinements made to the main design concept and spirit of the present invention that are not of substantial significance, but solve the same technical problem as the present invention, should be included within the scope of protection of the present invention.

Claims

1. A method for manufacturing rubber from waste rubber, characterized by, It comprises the following steps: Step one, preparation: the recycled waste rubber scraps are washed and dried at 40-50℃ to obtain dry waste rubber scraps; Step two, crushing: the dry waste rubber scraps obtained in step one are crushed into granules to obtain waste rubber granules; Step three, mixing: 60-70 parts of waste rubber granules, 20-30 parts of emulsifier, 5-10 parts of white carbon black, 3-5 parts of vulcanization accelerator and 7-10 parts of softening oil obtained in step two are mixed and then added to a mixing machine for mixing, and the temperature of the mixing machine is controlled at 100-110℃ to obtain the mixing raw material; Step four, secondary mixing: after the mixing raw material in step three is cooled, 3-5 parts of vulcanization accelerator are added to 100 parts of the mixing raw material obtained in step three, and then the mixture is mixed again, and the temperature of the mixing machine is controlled at 80℃ to obtain the secondary mixing rubber material; Step five, molding: the secondary mixing rubber material obtained in step four is conveyed to a granulator by a conveyor belt, and the secondary mixing rubber material is granulated or sheeted to obtain the rubber raw material.

2. The method for manufacturing rubber from waste rubber according to claim 1, characterized in that: The particle size of the waste rubber granules in step two is less than 100 mesh.

3. The method of claim 1, wherein the waste rubber is ground to a size of 1 mm or less. The vulcanization accelerator in step three is one of N-tert-butyl-2-benzothiazole sulfenamide (NS), N-cyclohexyl-2-benzothiazole sulfenamide (CZ), N, N, dicyclohexyl-2-benzothiazole sulfenamide (DZ), and N-oxydiethylene-2-benzothiazole sulfenamide (NOBS). ​ 4. The method of claim 1, wherein the waste rubber is ground to a size of 1 mm or less. The softening oil in step three is one of vegetable oil, mineral oil or rubber oil.

5. The method for manufacturing rubber from waste rubber according to claim 1, characterized in that: The mixing raw material in step four is cooled to 60-80℃.