CN116082537A - Preparation method and application of high-performance natural rubber - Google Patents
Preparation method and application of high-performance natural rubber Download PDFInfo
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- CN116082537A CN116082537A CN202211596377.9A CN202211596377A CN116082537A CN 116082537 A CN116082537 A CN 116082537A CN 202211596377 A CN202211596377 A CN 202211596377A CN 116082537 A CN116082537 A CN 116082537A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08C—TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
- C08C1/00—Treatment of rubber latex
- C08C1/14—Coagulation
- C08C1/15—Coagulation characterised by the coagulants used
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
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- C08K3/06—Sulfur
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2296—Oxides; Hydroxides of metals of zinc
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/80—Technologies aiming to reduce greenhouse gasses emissions common to all road transportation technologies
- Y02T10/86—Optimisation of rolling resistance, e.g. weight reduction
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Abstract
The invention relates to the field of natural rubber, in particular to a preparation method and application of high-performance natural rubber. The preparation method of the natural rubber at least comprises the following steps: (1) preparing a solidification auxiliary agent into a solution for later use; (2) Preparing a metal salt and a stabilizing auxiliary agent into a solution for later use; (3) Adding the prepared stable auxiliary solution into the latex base material, mixing and stirring the mixture stably, adding the prepared solidification auxiliary solution, stirring the mixture while adding the mixture, finally adding the prepared metal salt solution, uniformly mixing the mixture, standing the mixture, curing the coagulated mixture for 2 to 72 hours, dehydrating the coagulated mixture, washing the coagulated mixture, and drying the coagulated mixture to obtain the modified latex. The preparation method of the prepared high-performance natural rubber can effectively avoid the problems of environmental pollution, equipment corrosion, human health damage and the like caused by acid solidification; the coagulating system can shorten the coagulating time of the fresh latex, improve the coagulating effect of the fresh latex, reduce the production cost of products and the treatment cost of rubber processing wastewater, has good reproducibility and is easy for large-scale production.
Description
Technical Field
The invention relates to the field of natural rubber, in particular to a preparation method and application of high-performance natural rubber.
Background
The natural rubber is an industrial product with a natural high molecular compound as a main component, and is an important industrial raw material and strategic resource for national life and national security. Compared with imported tobacco flake rubber, the domestic natural rubber has low comprehensive performance, and is generally difficult to meet the rubber requirement of high-end products such as aviation tires, high-speed rail shock absorbers, heavy truck tires and the like, so that the rubber for the high-end products in China is seriously imported. Therefore, how to solve the technical problem of low comprehensive performance of natural rubber becomes one of key problems of important attention of domestic rubber enterprises.
In recent years, in order to solve the above-mentioned problems, domestic researchers have developed natural rubber with excellent comprehensive properties. For example, the property of domestic natural rubber is improved by independent microbial coagulation, enzyme coagulation or prolongation of coagulation and film curing time, as in the prior art, the Chinese patent application No. CN201510419988.X provides a preparation method of deproteinized natural rubber, which is added with a compound enzyme preparation in the preparation process of natural rubber, and can effectively reduce the protein content to help the rubber coagulation, but the microbial coagulation and the enzyme coagulation of the natural rubber in the actual operation process have slow coagulation speed and poor effect, and cannot meet the actual production requirement; the clot curing prolongs the production time of the product, greatly reduces the production efficiency of enterprises and increases the production cost of the enterprises; in addition, the curing of the rubber sheet needs to reform the existing standard rubber production line of rubber processing enterprises, so that the investment cost is high, the production efficiency of the enterprises is reduced, the actual large-scale industrialized work is difficult to carry out, and the popularization and the application in the actual production are difficult.
Therefore, in order to solve the problems, the applicant successfully prepares the high-performance natural rubber through corresponding researches and experiments, the comprehensive performance of the high-performance natural rubber is excellent, the production process is simple to operate, and enterprises do not need to greatly modify an additional sizing material production line. Therefore, the investment cost of enterprises is greatly reduced, the production efficiency is greatly improved, and the method has very excellent market prospect.
Disclosure of Invention
In order to solve the above problems, the first aspect of the present invention provides a method for preparing high-performance natural rubber, comprising at least the following steps: (1) preparing a solidification auxiliary agent into a solution for later use; (2) Preparing a metal salt and a stabilizing auxiliary agent into a solution for later use; (3) Adding the prepared stable auxiliary solution into the latex base material, mixing and stirring the mixture stably, adding the prepared solidification auxiliary solution, stirring the mixture while adding the mixture, finally adding the prepared metal salt solution, uniformly mixing the mixture, standing the mixture or adding the mixture of the solidification auxiliary solution and the metal salt solution together, curing the coagulated mixture for 2 to 72 hours after the solidification is completed, and dehydrating, washing and drying the coagulated mixture to obtain the modified latex.
As a preferable scheme, the mass ratio of the latex base material to the solidification assistant is 80-120: 0.01 to 10; the mass ratio of the latex base material to the metal salt is 80-120: 0.01 to 1; the mass ratio of the latex base material to the stabilizing auxiliary agent is 80-120: 0.01 to 0.5.
As a preferred scheme, the mass ratio of the latex base material to the solidification assistant is 100:0.01 to 0.1; the mass ratio of the latex base material to the metal salt is 100:0.01 to 0.1; the mass ratio of the latex base material to the stabilizing auxiliary agent is 100:0.01 to 0.1.
As a preferred scheme, the mass ratio of the latex base material to the solidification assistant 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 stabilizing auxiliary agent is 100:0.05.
as a preferable scheme, the coagulation aid is at least one of microbial coagulant, neutral protease, alkaline protease, acid protease, lysozyme, papain and bromelain; the activity of the solidification assistant is 1000-5000000 u/g.
As a preferred embodiment, the coagulation aid is alkaline protease and/or neutral protease; the activity of the solidification assistant is 100000 ～ 300000u/g.
As a preferred embodiment, the latex binder contains 0.01 to 0.1% ammonia.
As a preferred embodiment, the latex binder contains 0.03 to 0.07% ammonia.
As a preferred embodiment, the latex binder is Hevea brasiliensis natural latex.
As a preferable scheme, the metal salt is at least one of sodium salt and calcium salt of strong acid.
As a preferable scheme, 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.
As a preferable scheme, the metal salt is at least one of sodium chloride, calcium chloride and calcium nitrate.
As a preferable scheme, the metal salt is a mixture of sodium chloride and calcium chloride, and the mass ratio is 1:1.
As a preferred embodiment, the metal salt is calcium nitrate.
As a preferable scheme, the stabilizing auxiliary is at least one of a heat stabilizer, a viscosity stabilizer and a surfactant.
As a preferable scheme, the heat stabilizer is a calcium-zinc stabilizer; the viscosity stabilizer is any one of hydroxylamine sulfate or alkaline neutralized hydroxylamine sulfate.
As a preferable embodiment, 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.
As a preferred embodiment, the stabilizing aid is a surfactant, which is sodium dodecyl sulfate or lauric acid.
In the present application, a specific sodium dodecyl sulfate or lauric acid is added as a surfactant stabilizer to be blended with a specific ratio of an enzyme preparation to a metal salt, whereby an excellent natural rubber coagulation preparation effect can be achieved. The applicant speculates that: when the mass ratio of the latex base material to the solidification assistant 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 stabilizing auxiliary agent is 100: when the pH value of the aqueous solution is 0.05, the synergistic effect of the aqueous solution and the aqueous solution can strengthen the rapid degradation effect on non-latex components in a system in a solidification system, acidic media are uniformly generated in the system, short chain molecular aggregation is promoted, the tension effect of metal salt molecules and a surfactant is cooperated, the system consistency is improved, and meanwhile, the local solidification effect is accelerated, so that the effect of integral rapid molding is achieved.
As a preferable scheme, the mass concentration of the solidification assistant solution is 1-15%; the mass concentration of the metal salt and the stabilizing auxiliary solution is 1-10%.
As a preferable scheme, the mass concentration of the solidification assistant solution is 5-10%; the mass concentration of the metal salt and the stabilizing auxiliary solution is 5-10%.
The second aspect of the invention provides an application of the preparation method of the high-performance natural rubber, comprising an application of the preparation method of the high-performance natural rubber in a preparation process of a natural rubber material.
The beneficial effects are that:
1. the preparation method of the high-performance natural rubber provided by the invention can effectively avoid the problems of environmental pollution, equipment corrosion, human health damage and the like caused by acid solidification; the coagulating system can shorten the coagulating time of the fresh latex, improve the coagulating effect of the fresh latex, reduce the production cost of the product and the treatment cost of the rubber processing wastewater, and the prepared product has better performance than that of imported No. 3 tobacco flake rubber and good reproducibility, and is easy for large-scale production.
2. According to the preparation method of the high-performance natural rubber, provided by the invention, the specific sodium dodecyl sulfate or lauric acid is added as the surface active stabilizer to be matched with the specific ratio of the enzyme preparation to the metal salt, so that an excellent natural rubber coagulation preparation effect can be achieved, and particularly when the mass ratio of the latex base material to the coagulation auxiliary agent 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 stabilizing auxiliary agent is 100: when the pH value is 0.05, the synergistic effect of the two components can strengthen the rapid degradation effect on non-latex components in a system in a solidification system, acidic media are uniformly generated in the system, short chain molecular aggregation is promoted, the tension effect of metal salt molecules and a surfactant is cooperated, and the local solidification effect is accelerated while the system consistency is improved.
Detailed Description
Example 1
Example 1 provides a method for preparing high-performance natural rubber, comprising the following steps: (1) Preparing 50g of sodium dodecyl sulfate into 10% (mass percentage concentration) solution for later use; (2) Dissolving 30g of alkaline protease in an aqueous solution to prepare a solution with the concentration of 5% (mass percentage concentration) for later use, and on the other hand, dissolving 30g of a mixture of calcium chloride and sodium chloride (which are mixed according to the mass ratio of 1:1) in the aqueous solution to prepare a salt solution with the concentration of 10% (mass percentage concentration) for later use; (3) Taking a proper amount of Brazilian hevea natural latex with ammonia content of 0.05%, adding 0.05% (calculated by dry colloid amount) of sodium dodecyl sulfate solution, adding 0.07% (calculated by dry colloid amount) of alkaline proteinase solution, finally adding 0.05% (calculated by dry colloid amount) of calcium chloride and sodium chloride mixture solution, stirring and adding, fully mixing a coagulating system with the latex, standing, curing for 8 hours after the latex is completely coagulated, and then performing creping, washing, granulating and drying to obtain the final product.
The vulcanization formula of the vulcanized rubber of the obtained natural rubber is as follows: 100g of dry glue, 6g of zinc oxide, 3.5g of sulfur, 0.5g of stearic acid and 0.5g of accelerator M.
The mechanical properties of the vulcanizate of the obtained natural rubber were tested as follows in table 1:
TABLE 1
Example 2
Example 2 provides a method for preparing high-performance natural rubber, comprising the following steps: (1) Preparing 30g of sodium dodecyl sulfate into 10% (mass percentage concentration) solution for later use; (2) Dissolving 40g of alkaline protease in an aqueous solution to prepare a solution with the concentration of 10% (mass percentage concentration) for later use, and dissolving 30g of calcium chloride in the aqueous solution to prepare a salt solution with the concentration of 10% (mass percentage concentration) for later use; (3) Taking a proper amount of Brazilian hevea natural latex with ammonia content of 0.03%, adding 0.05% (calculated by dry colloid amount) of sodium dodecyl sulfate solution, adding 0.05% (calculated by dry colloid amount) of alkaline proteinase solution, finally adding 0.1% (calculated by dry colloid amount) of calcium chloride solution, stirring and adding, fully mixing a coagulating system with the latex, standing, curing for 8 hours after the latex is completely coagulated, and then carrying out pressure creping, washing, granulating and drying to obtain the final product.
The recipe of the vulcanized rubber of the natural rubber obtained in this example is the same as that of example 1.
The mechanical properties of the vulcanizate of the resulting natural rubber were tested as follows in table 2:
TABLE 2
Example 3
Example 3 provides a method for preparing high-performance natural rubber, comprising the following steps: (1) Preparing 50g of lauric acid into a solution with the mass percent concentration of 10 percent for later use; (2) Dissolving 40g of neutral protease in an aqueous solution to prepare a solution with the concentration of 10% (mass percentage concentration) for later use, and dissolving 20g of calcium nitrate in the aqueous solution to prepare a salt solution with the concentration of 10% (mass percentage concentration) for later use; (3) Taking a proper amount of Brazilian hevea natural latex with ammonia content of 0.05%, adding 0.08% (dry colloid amount) lauric acid solution, adding 0.07% (dry colloid amount) neutral proteinase solution, finally adding 0.05% (dry colloid amount) calcium nitrate solution, stirring and adding, fully mixing a coagulating system with the latex, standing, curing for 8 hours after the latex is completely coagulated, and then performing pressure creping, washing, granulating and drying to obtain the final product.
The recipe of the vulcanized rubber of the natural rubber obtained in this example is the same as that of example 1.
The mechanical properties of the vulcanizate of the resulting natural rubber were tested as follows in table 3:
TABLE 3 Table 3
Example 4
Example 4 provides a method for preparing high-performance natural rubber, comprising the following steps: (1) Preparing 20g of lauric acid into a 5% (mass percentage concentration) solution for later use; (2) Dissolving 40g of neutral protease in an aqueous solution to prepare a solution with the concentration of 10% (mass percentage concentration) for later use, and dissolving 20g of calcium nitrate in the aqueous solution to prepare a salt solution with the concentration of 10% (mass percentage concentration) for later use; (3) Taking a proper amount of natural rubber latex of Hevea brasiliensis with ammonia content of 0.03%, adding 0.05% (calculated by dry colloid amount) of sodium laurate solution, adding 0.05% (calculated by dry colloid amount) of neutral proteinase solution, finally adding 0.1% (calculated by dry colloid amount) of calcium nitrate solution, stirring and adding, fully mixing a coagulating system with the rubber latex, standing, curing for 8 hours after the latex is completely coagulated, and then carrying out creping, washing, granulating and drying to obtain the rubber latex.
The recipe of the vulcanized rubber of the natural rubber obtained in this example is the same as that of example 1.
The mechanical properties of the vulcanizate of the resulting natural rubber were tested as follows in table 4:
TABLE 4 Table 4
Claims (10)
1. A preparation method of high-performance natural rubber is characterized by comprising the following steps: the method at least comprises the following steps: (1) preparing a solidification auxiliary agent into a solution for later use; (2) Preparing a metal salt and a stabilizing auxiliary agent into a solution for later use; (3) Adding the prepared stable auxiliary solution into the latex base material, mixing and stirring the mixture stably, adding the prepared solidification auxiliary solution, stirring the mixture while adding the mixture, finally adding the prepared metal salt solution, uniformly mixing the mixture, standing the mixture or adding the mixture of the solidification auxiliary solution and the metal salt solution together, curing the coagulated mixture for 2 to 72 hours after the solidification is completed, and dehydrating, washing and drying the coagulated mixture to obtain the modified latex.
2. The method for producing a high-performance natural rubber according to claim 1, wherein: the mass ratio of the latex base material to the solidification auxiliary agent is 80-120: 0.01 to 10; the mass ratio of the latex base material to the metal salt is 80-120: 0.01 to 1; the mass ratio of the latex base material to the stabilizing auxiliary agent is 80-120: 0.01 to 0.5.
3. The method for producing a high-performance natural rubber according to claim 2, characterized in that: the coagulation auxiliary agent is at least one of microbial coagulant, neutral protease, alkaline protease, acid protease, lysozyme, papain and bromelain; the activity of the solidification assistant is 1000-5000000 u/g.
4. A method for producing a high-performance natural rubber according to claim 3, wherein: the metal salt is at least one of sodium salt and calcium salt of strong acid.
5. The method for producing a high-performance natural rubber according to claim 4, wherein: 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.
6. The method for producing a high-performance natural rubber according to any one of claims 1 to 5, characterized in that: the stabilizing auxiliary agent is at least one of a heat stabilizer, a viscosity stabilizer and a surfactant.
7. The method for producing a high-performance natural rubber according to claim 6, wherein: the heat stabilizer is a calcium-zinc stabilizer; the viscosity stabilizer is any one of hydroxylamine sulfate or alkaline neutralized hydroxylamine sulfate.
8. The method for producing a high-performance natural rubber according to claim 6, wherein: the surfactant is at least one of sodium dodecyl sulfate, lauric acid, potassium laurate, myristic acid, polysaccharide, alkyl glycoside, fatty alcohol polyoxyethylene ether sodium sulfate and alkyl polyoxyethylene ether.
9. The method for producing a high-performance natural rubber according to claim 8, wherein: the mass concentration of the solidification assistant solution is 1-15%; the mass concentration of the metal salt and the stabilizing auxiliary solution is 1-10%.
10. Use of the method for the preparation of high-performance natural rubber according to any one of claims 1 to 9, characterized in that: the preparation method of the high-performance natural rubber is applied to the preparation process of natural rubber materials.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211596377.9A CN116082537A (en) | 2022-12-12 | 2022-12-12 | Preparation method and application of high-performance natural rubber |
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| CN202211596377.9A CN116082537A (en) | 2022-12-12 | 2022-12-12 | Preparation method and application of high-performance natural rubber |
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