A preparation method and application of high-performance natural rubber

Abstract

The present invention relates to the field of natural rubber, and in particular to a method for preparing high-performance natural rubber and its application. The method for preparing natural rubber comprises at least the following steps: (1) preparing a coagulation aid into a solution for standby use; (2) preparing a metal salt and a stabilizing aid into a solution for standby use; (3) taking a latex base material and adding the prepared stabilizing aid solution, mixing and stirring to stabilize, then adding the prepared coagulation aid solution, stirring while adding, and finally adding the prepared metal salt solution and mixing evenly and then standing, and after complete coagulation, the clot is matured for 2 to 72 hours, and then dehydrated, washed and dried to obtain the obtained product. The method for preparing the obtained high-performance natural rubber can effectively avoid the problems of environmental pollution, equipment corrosion and damage to human health caused by acid coagulation; the coagulation system can shorten the coagulation time of fresh latex, improve the coagulation effect of fresh latex, reduce the production cost of the product and the treatment cost of rubber processing wastewater, and has good reproducibility and is easy to mass produce.

Description

Technical Field

[0001] The invention relates to the field of natural rubber, and in particular to a preparation method and application of high-performance natural rubber. Background Art

[0002] Natural rubber is an industrial product whose main component is natural polymer compounds. At the same time, natural rubber is an important industrial raw material and strategic resource related to national economy, people's livelihood and national security. At present, compared with imported smoked rubber, the comprehensive performance of domestic natural rubber is low, and it is usually difficult to meet the demand for rubber for high-end products such as aviation tires, high-speed rail shock absorbers and heavy truck tires, resulting in my country's high-end products The rubber is heavily dependent on imports. Therefore, how to solve the technical problem of low comprehensive performance of natural rubber has become one of the key issues that domestic rubber companies focus on.

[0003] In recent years, in order to solve the above problems, domestic scientific researchers have gradually carried out research and development work on natural rubber with excellent comprehensive performance. For example, the performance of domestic natural rubber can be improved by separate microbial coagulation, enzyme coagulation or extended clot and film maturation time. For example, the prior art Chinese invention application CN201510419988.X provides a method for preparing deproteinized natural rubber, which adds a composite enzyme preparation during the natural rubber preparation process. Although it can effectively reduce the protein content and help rubber coagulation, the microbial coagulation and enzyme coagulation of natural rubber in the actual operation process are slow and poor in effect, and cannot meet the actual production needs; and clot maturation prolongs the production time of the product, greatly reduces the production efficiency of the enterprise, and increases its production cost; in addition, film maturation requires the transformation of the existing standard rubber production line of the rubber processing enterprise, which has high investment costs and reduces the production efficiency of the enterprise, making it difficult to carry out actual large-scale industrialization work and difficult to promote and apply in actual production.

[0004] Therefore, in order to solve the above problems, the applicant has successfully prepared a high-performance natural rubber through corresponding research and experiments, which has excellent comprehensive performance and simple production process operation, and the enterprise does not need to carry out substantial transformation of additional rubber production lines. Therefore, the investment cost of the enterprise is greatly reduced and the production efficiency is greatly improved, which has a very excellent market prospect. Summary of the invention

[0005] In order to solve the above problems, the first aspect of the present invention provides a method for preparing high-performance natural rubber, which comprises at least the following steps: (1) preparing a coagulation aid into a solution for later use; (2) preparing a metal salt and a stabilizing aid into a solution for later use; (3) taking a latex base material and adding the prepared stabilizing aid solution, mixing and stirring until stable, then adding the prepared coagulation aid solution, stirring while adding, and finally adding the prepared metal salt solution, mixing evenly, and then standing or compounding the coagulation aid solution and the metal salt solution and adding them together, and after complete coagulation, ripening the clot for 2 to 72 hours, dehydrating, washing, and drying to obtain the obtained product.

[0006] As a preferred solution, the mass ratio of the latex base material to the coagulation aid is 80-120:0.01-10; the mass ratio of the latex base material to the metal salt is 80-120:0.01-1; the mass ratio of the latex base material to the stabilization aid is 80-120:0.01-0.5.

[0007] As a preferred solution, the mass ratio of the latex base material to the coagulation aid is 100:0.01-0.1; the mass ratio of the latex base material to the metal salt is 100:0.01-0.1; the mass ratio of the latex base material to the stabilization aid is 100:0.01-0.1.

[0008] As a preferred solution, the mass ratio of the latex base material to the coagulation aid is 100:0.05; the mass ratio of the latex base material to the metal salt is 100:0.1; and the mass ratio of the latex base material to the stabilization aid is 100:0.05.

[0009] As a preferred solution, the coagulation aid is at least one of a microbial coagulant, a neutral protease, an alkaline protease, an acidic protease, a lysozyme, a papain, and a bromelain; and the activity of the coagulation aid is 1000 to 5000000 u / g.

[0010] As a preferred solution, the coagulation aid is alkaline protease and / or neutral protease; the activity of the coagulation aid is 100,000 to 300,000 u / g.

[0011] As a preferred solution, the ammonia content of the latex base material is 0.01-0.1%.

[0012] As a preferred solution, the ammonia content of the latex base material is 0.03-0.07%.

[0013] As a preferred solution, the latex base material is natural latex from Hevea brasiliensis.

[0014] As a preferred solution, the metal salt is at least one of a strong acid sodium salt and a strong acid calcium salt.

[0015] As a preferred solution, the strong acid sodium salt is any one of sodium chloride, sodium nitrate, sodium hypochlorite, and sodium sulfate; the strong acid calcium salt is any one of calcium chloride, calcium nitrate, calcium hypochlorite, and calcium sulfate.

[0016] As a preferred solution, the metal salt is at least one of sodium chloride, calcium chloride and calcium nitrate.

[0017] As a preferred solution, the metal salt is a mixture of sodium chloride and calcium chloride in a mass ratio of 1:1.

[0018] As a preferred solution, the metal salt is calcium nitrate.

[0019] As a preferred solution, the stabilizing aid is at least one of a heat stabilizer, a viscosity stabilizer, and a surfactant.

[0020] As a preferred solution, the heat stabilizer is a calcium zinc stabilizer; the viscosity stabilizer is any one of hydroxylamine sulfate or alkaline neutralized hydroxylamine sulfate.

[0021] As a preferred solution, the surfactant is at least one of sodium dodecyl sulfate, lauric acid, potassium laurate, myristic acid, polysaccharide, alkyl glycoside, sodium fatty alcohol polyoxyethylene ether sulfate, and alkyl polyoxyethylene ether.

[0022] As a preferred solution, the stabilizing agent is a surfactant, and the surfactant is sodium dodecyl sulfate or lauric acid.

[0023] In the present application, by adding specific sodium dodecyl sulfate or lauric acid as a surfactant stabilizer and matching a specific enzyme preparation with a metal salt, an excellent natural rubber coagulation preparation effect can be achieved. The applicant speculates that when the mass ratio of latex base material to coagulation aid is 100:0.05; the mass ratio of latex base material to metal salt is 100:0.1; the mass ratio of latex base material to stabilizing aid is 100:0.05, the synergistic effect of the several can enhance the rapid degradation of non-latex components in the system in the coagulation system, uniformly generate acidic medium inside the system, promote the aggregation of short-chain molecules, coordinate the tension effect of metal salt molecules and surfactants, improve the consistency of the system, and accelerate the local coagulation effect, thereby achieving the effect of overall rapid molding.

[0024] As a preferred solution, the mass concentration of the coagulation aid solution is 1-15%; the mass concentration of the metal salt stabilization aid solution is 1-10%.

[0025] As a preferred solution, the mass concentration of the coagulation aid solution is 5-10%; the mass concentration of the metal salt stabilization aid solution is 5-10%.

[0026] The second aspect of the present invention provides an application of the method for preparing the high-performance natural rubber, including application of the method for preparing the high-performance natural rubber in a natural rubber material preparation process.

[0027] Beneficial effects:

[0028] 1. The present invention provides a method for preparing high-performance natural rubber, which can effectively avoid the problems of environmental pollution, equipment corrosion and damage to human health caused by acid coagulation; the coagulation system can shorten the coagulation time of fresh latex, improve the coagulation effect of fresh latex, reduce the production cost of the product and the treatment cost of rubber processing wastewater, and the prepared product has better performance than imported No. 3 smoked sheet rubber and has good reproducibility, and is easy to mass produce.

[0029] 2. The present invention provides a method for preparing high-performance natural rubber, which can achieve excellent natural rubber coagulation preparation effect by adding specific sodium dodecyl sulfate or lauric acid as a surfactant stabilizer in combination with a specific ratio of enzyme preparation and metal salt, especially when the mass ratio of latex base material to coagulation aid is 100:0.05; the mass ratio of latex base material to metal salt is 100:0.1; the mass ratio of latex base material to stabilizing aid is 100:0.05, the synergistic effect of the above can enhance the rapid degradation of non-latex components in the coagulation system, uniformly generate acidic medium inside the system, promote the aggregation of short-chain molecules, coordinate the tension effect of metal salt molecules and surfactants, improve the consistency of the system, and accelerate the local coagulation effect. DETAILED DESCRIPTION

[0030] Example 1

[0031] Embodiment 1 provides a method for preparing high-performance natural rubber, comprising the following steps: (1) preparing a 10% (mass percentage concentration) solution with 50 g of sodium dodecyl sulfate for later use; (2) dissolving 30 g of alkaline protease in an aqueous solution to prepare a 5% (mass percentage concentration) solution for later use; on the other hand, dissolving 30 g of a mixture of calcium chloride and sodium chloride (mixed in a mass ratio of 1:1) in an aqueous solution to prepare a salt solution with a concentration of 10% (mass percentage concentration) for later use; (3) taking an appropriate amount of natural latex of Hevea brasiliensis with an ammonia content of 0.05%, adding 0.05% (calculated on the mass of dry rubber) of sodium dodecyl sulfate solution, then adding 0.07% (calculated on the mass of dry rubber) of alkaline protease solution, and finally adding 0.05% (calculated on the mass of dry rubber) of a mixture of calcium chloride and sodium chloride, stirring and adding, so that the coagulation system is fully mixed with the latex and then allowed to stand, after the latex is completely coagulated, ripening for 8 hours, and then pressing, washing, granulating, and drying to obtain the product.

[0032] The vulcanization formula of the obtained natural rubber vulcanizate is: 100g dry rubber, 6g zinc oxide, 3.5g sulfur, 0.5g stearic acid, and 0.5g promoter.

[0033] The mechanical properties test results of the obtained natural rubber vulcanizate are shown in Table 1 below:

[0034] Table 1

[0035]

[0036] Example 2

[0037] Embodiment 2 provides a method for preparing high-performance natural rubber, which comprises the following steps: (1) preparing a 10% (mass percentage concentration) solution with 30 g of sodium dodecyl sulfate for standby use; (2) dissolving 40 g of alkaline protease in an aqueous solution to prepare a 10% (mass percentage concentration) solution for standby use, and on the other hand, dissolving 30 g of calcium chloride in an aqueous solution to prepare a 10% (mass percentage concentration) salt solution for standby use; (3) taking an appropriate amount of natural latex of Hevea brasiliensis with an ammonia content of 0.03%, adding 0.05% (calculated on the mass of dry rubber) of sodium dodecyl sulfate solution, then adding 0.05% (calculated on the mass of dry rubber) of alkaline protease solution, and finally adding 0.1% (calculated on the mass of dry rubber) of calcium chloride solution, adding while stirring, so that the coagulation system is fully mixed with the latex, and then standing, after the latex is completely coagulated, ripening for 8 hours, and then pressing, washing, granulating, and drying to obtain the product.

[0038] The formula of the vulcanized rubber of natural rubber obtained in this example is the same as that in Example 1.

[0039] The mechanical properties test results of the obtained natural rubber vulcanizate are shown in Table 2 below:

[0040] Table 2

[0041]

[0042] Example 3

[0043] Embodiment 3 provides a method for preparing high-performance natural rubber, which comprises the following steps: (1) preparing a 10% (mass percentage concentration) solution of 50g lauric acid for later use; (2) dissolving 40g neutral protease in an aqueous solution to prepare a 10% (mass percentage concentration) solution for later use; on the other hand, dissolving 20g calcium nitrate in an aqueous solution to prepare a 10% (mass percentage concentration) salt solution for later use; (3) taking an appropriate amount of natural latex of Hevea brasiliensis with an ammonia content of 0.05%, adding 0.08% (calculated on the mass of dry rubber) lauric acid solution, then adding 0.07% (calculated on the mass of dry rubber) neutral protease solution, and finally adding 0.05% (calculated on the mass of dry rubber) calcium nitrate solution, adding while stirring, so that the coagulation system and latex are fully mixed and then allowed to stand, after the latex is completely coagulated, ripening for 8h, and then pressing, washing, granulating, and drying to obtain the product.

[0044] The formula of the vulcanized rubber of natural rubber obtained in this example is the same as that in Example 1.

[0045] The mechanical properties test results of the obtained natural rubber vulcanizate are shown in Table 3 below:

[0046] Table 3

[0047]

[0048] Example 4

[0049] Embodiment 4 provides a method for preparing high-performance natural rubber, which comprises the following steps: (1) preparing a 5% (mass percentage concentration) solution of 20 g of lauric acid for later use; (2) dissolving 40 g of neutral protease in an aqueous solution to prepare a 10% (mass percentage concentration) solution for later use; on the other hand, dissolving 20 g of calcium nitrate in an aqueous solution to prepare a 10% (mass percentage concentration) salt solution for later use; (3) taking an appropriate amount of natural latex of Hevea brasiliensis with an ammonia content of 0.03%, adding 0.05% (calculated on the mass of dry rubber) sodium laurate solution, then adding 0.05% (calculated on the mass of dry rubber) neutral protease solution, and finally adding 0.1% (calculated on the mass of dry rubber) calcium nitrate solution, adding while stirring, so that the coagulation system is fully mixed with the latex, and then standing, after the latex is completely coagulated, ripening for 8 hours, and then pressing, washing, granulating, and drying to obtain the product.

[0050] The formula of the vulcanized rubber of natural rubber obtained in this example is the same as that in Example 1.

[0051] The mechanical properties test results of the obtained natural rubber vulcanizate are shown in Table 4 below:

[0052] Table 4

[0053]

Claims

1. A method for preparing high-performance natural rubber, characterized in that: The steps include at least the following steps: (1) preparing a coagulation aid into a solution for later use; (2) preparing a metal salt and a stabilizing aid into a solution for later use; (3) adding the prepared stabilizing aid solution to a latex base material, mixing and stirring until stable, then adding the prepared coagulation aid solution, stirring while adding, and finally adding the prepared metal salt solution, mixing evenly, and then standing or mixing the coagulation aid solution and the metal salt solution and then adding them together, and after the coagulation is complete, ripening the clot for 2 to 72 hours, dehydrating, washing, and drying to obtain the clot; The mass ratio of the latex base material to the coagulation aid is 100:0.05; the mass ratio of the latex base material to the metal salt is 100:0.1; the mass ratio of the latex base material to the stabilization aid is 100:0.05; The coagulation aid is alkaline protease and / or neutral protease; the activity of the coagulation aid is 100000~300000u / g; The ammonia content of the latex base material is 0.03-0.07%, and the latex base material is natural latex of Hevea brasiliensis; The stabilizing aid is a surfactant, and the surfactant is sodium lauryl sulfate or lauric acid; The mass concentration of the coagulation aid solution is 5-10%; the mass concentration of the metal salt and stabilization aid solution is 5-10%.

2. The method for preparing high-performance natural rubber according to claim 1, characterized in that: The metal salt is at least one of a strong acid sodium salt and a strong acid calcium salt.

3. The method for preparing high-performance natural rubber according to claim 2, characterized in that: The strong acid sodium salt is any one of sodium chloride, sodium nitrate, sodium hypochlorite and sodium sulfate; the strong acid calcium salt is any one of calcium chloride, calcium nitrate, calcium hypochlorite and calcium sulfate.

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