Low-Mooney high-performance natural rubber and preparation method thereof

Abstract

The embodiment of the invention relates to the technical field of rubber flocculation, and discloses low-Mooney high-performance natural rubber and a preparation method thereof, and the preparation method adopts fresh latex, a clastic enzyme and a flocculant to prepare the natural rubber. The natural rubber with low Mooney viscosity and high performance is prepared through the matching of the decomposition enzyme and the flocculating agent. The raw materials adopted in the method are few in variety and easy to obtain, and the cost of the raw materials can be reduced. Meanwhile, the raw materials adopted by the preparation method are environment-friendly and are not easy to cause pollution.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of rubber flocculation, and in particular to a low-Mooney high-performance natural rubber and a preparation method thereof. Background Art

[0002] As a biopolymer material, natural rubber contains other trace groups in addition to the main cis-isoprene structure on its molecular chain. It is these trace groups that lead to the unpredictability of the performance of natural rubber compared to synthetic rubber, such as storage Mooney increase, hardening phenomenon, vulcanization acceleration effect, supramolecular network structure, etc.

[0003] As an industrial raw material, natural rubber has excellent performance and is difficult to replace. Modern processing technology generally uses it with additives and other rubbers, vulcanizes it to strengthen or adjust its various properties, and before producing products, it needs to be subjected to steps such as open and closed mixing by machines.

[0004] Due to the high Mooney viscosity of natural rubber, there are two problems when processing it in the laboratory or factory:

[0005] 1. Excessively high Mooney value of natural rubber often leads to processing difficulties. Not only does the energy consumption of open and closed mixers increase, but small and medium-sized machines are also accompanied by BAS risks. In addition, high Mooney rubber can easily lead to uneven dispersion of fillers and additives. Therefore, in factory production, it is necessary to perform plasticizing and other operations to reduce the Mooney value before adding other rubbers, additives, fillers and other series of formulas, resulting in high production costs and low efficiency.

[0006] 2. The Mooney value of synthetic rubber is generally lower than that of natural rubber. When high and low Mooney rubbers are used together, compatibility problems are likely to occur. Obvious stratification is likely to occur at the molecular level, and the degree of filler dispersion is greatly affected. Such phenomena will lead to excessive loss of formula performance.

[0007] At present, the production of low Mooney natural rubber is mainly based on low Mooney constant viscosity, that is, to keep the Mooney value change small. The traditional process is to add additional compounds such as amines, thiols and hydrazine hydrates when flocculating natural rubber to prevent rubber molecules from generating aldehyde groups and self-polymerization. The Mooney value of this constant viscosity low Mooney natural rubber is between 50-60, which can maintain a small change in the Mooney value for a long time. However, according to research, it has an adverse effect on the tensile properties of natural rubber. The greater the amount used, the more obvious this adverse effect is. The tensile strength and elongation at break show a fluctuating downward trend. In addition, the use of hydroxylamine, thiol and hydrazine hydrate compounds in the aqueous phase is not environmentally friendly, and there is also the disadvantage of high cost.

[0008] Therefore, how to provide a natural rubber with both low Mooney and excellent physical properties is an urgent problem to be solved by researchers in the current relevant technical field. Summary of the invention

[0009] In order to solve the above problems, the invention object of the first aspect of the present application is to provide a low Mooney high-performance natural rubber, which has the characteristics of low Mooney value and excellent physical properties.

[0010] The second aspect of the invention of the present application aims to provide a method for preparing low-Mooney high-performance natural rubber, which can be used to prepare natural rubber with excellent performance. At the same time, the raw materials are environmentally friendly and easy to obtain, less materials are required, and the cost does not increase.

[0011] In order to achieve the above object, the present invention provides the following technical solutions:

[0012] The invention provides a low Mooney high-performance natural rubber, which is prepared from the following components: fresh latex, decomposing enzyme and flocculant;

[0013] Based on the mass of the fresh latex, the mass of the decomposition enzyme is 0.05% to 0.5% of the mass of the dry rubber of the fresh latex, and the decomposition enzyme includes at least one of a protease or a phospholipase;

[0014] The mass ratio of the fresh latex to the flocculant is: 100:(0.3-2.0), and the flocculant is a cationic quaternary ammonium salt.

[0015] Preferably, the flocculant is selected from at least one of polydimethyldiallylammonium chloride, acrylamide / dimethyldiallylammonium chloride copolymer, pyridinium quaternary ammonium salt type cationic polyacrylamide, modified urea-formaldehyde resin quaternary ammonium salt, dicyandiamide / epichlorohydrin polymer, dicyandiamide / formaldehyde polymer, and dimethylamine / epichlorohydrin polymer.

[0016] Preferably, the flocculant consists of dimethyldiallylammonium chloride and dimethylamine / epichlorohydrin polymer.

[0017] Preferably, the decomposing enzyme comprises protease and phospholipase, and the mass ratio of the protease to the phospholipase is 5:1.

[0018] Preferably, the protease is alkaline protease and the phospholipase is phospholipase D.

[0019] The present invention also provides a method for preparing any of the above-mentioned low Mooney high-performance natural rubbers, comprising the following steps:

[0020] S1. The decomposing enzyme is added to the fresh latex, stirred, and the fresh latex is hydrolyzed to obtain the first latex;

[0021] S2. adding a flocculant to the first latex, stirring, and allowing to stand to obtain a latex clot;

[0022] S3. The latex coagulates are fished out, creped, granulated, washed with water, and dried after dripping to obtain natural rubber.

[0023] Preferably, in S1, the step of adding the decomposing enzyme to the fresh latex comprises:

[0024] The decomposition enzyme is added to water to prepare a decomposition enzyme aqueous solution.

[0025] Preferably, in the aqueous solution of decomposing enzyme, the mass fraction of the decomposing enzyme is 10%.

[0026] Preferably, the activity of the degrading enzyme is at least 100,000 u / g.

[0027] Preferably, the dry rubber content of the fresh latex is 17-50wt%, and the ammonia content is within 0.5wt%.

[0028] Based on the above technical solutions, the present invention has the following technical effects:

[0029] 1. A low-Mooney high-performance natural rubber provided by the present invention is prepared by including fresh latex, decomposing enzyme and flocculant. Among them, the decomposing enzyme is used to enzymolyze latex, eliminate rubber supramolecular network nodes, and reduce the density of latex molecular network. The flocculant adopts quaternary ammonium salt flocculant, and the amine hydrogen bonds carried have the function of shielding the α, ω terminal hydrogen bonds and ionic bonds exposed after enzymolysis, which can prevent the latex from generating cross-linking points again after enzymolysis. The amine groups carried by the flocculant can react with natural rubber to generate aldehyde groups, and can also prevent the Mooney viscosity from being greatly increased. That is, the flocculant plays the role of latex flocculation and separation, and reaction of natural rubber molecules, achieving the effect of reducing the density of supramolecular gel network. Therefore, the natural rubber provided by the present invention greatly reduces the Mooney value, while maintaining the advantages in mechanical properties, which is conducive to solving the problems of high cost and low efficiency caused by high rubber damping in industrial production processes.

[0030] 2. The present invention provides a method for preparing a low-Mooney high-performance natural rubber, which prepares a natural rubber with low Mooney and excellent physical properties through the reaction of fresh latex, decomposing enzyme and flocculant. The method uses a small number of raw materials, which are easy to obtain and help reduce the cost of raw materials. In addition, the raw materials used in the preparation method are environmentally friendly and not easy to cause pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The figure is a schematic flow chart of the method for preparing low Mooney high-performance natural rubber of the present invention. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below in conjunction with specific embodiments. The present invention provides preferred embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0033] Before further describing various embodiments of the compounds / compositions and methods of the present disclosure in more detail through exemplary descriptions, examples and results, it should be understood that the embodiments of the present disclosure are not limited to the details of the methods and compositions described in the following description in application. The description provided herein is for illustrative purposes only and is not to be interpreted in a limiting sense. The inventive concepts of the present disclosure can have other embodiments or can be practiced or implemented in various ways. Therefore, the language used herein is intended to give the broadest scope and meaning; and the embodiments are intended to be exemplary, not exhaustive, and are not intended to limit the present disclosure to these specific embodiments. Moreover, it should be understood that the wording and terminology used herein are for the purpose of description and should not be considered restrictive unless otherwise stated. In addition, in the following detailed description, many specific details are listed in order to provide a more thorough understanding of the present disclosure.

[0034] However, it is obvious to those skilled in the art that the embodiments of the present disclosure can be practiced without these specific details. In other cases, features known to those skilled in the art are not described in detail to avoid unnecessary complex descriptions. It is intended that all substitutions, replacements, modifications and equivalents obvious to those skilled in the art are included within the scope of the present disclosure. According to the present disclosure, all compounds / compositions disclosed herein and their preparation methods, applications and uses can be prepared and implemented without undue experimentation.

[0035] Thus, although the compounds / compositions and methods of the present disclosure have been described according to specific embodiments, it will be apparent to those skilled in the art that changes may be made to the formulations, compounds or compositions and / or methods, as well as the steps or order of steps of the methods described herein, without departing from the spirit and scope of the inventive concepts of the present disclosure.

[0036] As used herein, any reference to "one embodiment" or "an embodiment" means that a particular element, feature, structure, or characteristic described in conjunction with the implementation is included in at least one embodiment. The phrase "in one embodiment" appearing in multiple places in the specification does not necessarily refer to the same embodiment.

[0037] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present disclosure shall have the meanings commonly understood by those of ordinary skill in the art. In addition, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular.

[0038] Example 1

[0039] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0040] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0041] (2) Add dimethyldiallyl ammonium chloride, a quaternary ammonium salt flocculant, to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. The added mass of dimethyldiallyl ammonium chloride is 0.3 wt% of the mass of the fresh latex.

[0042] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0043] Example 2

[0044] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0045] (1) A decomposition enzyme aqueous solution is prepared with a protease and a phospholipase having an activity of 100000u / g as solutes, wherein the mass fraction of the enzyme in the decomposition enzyme aqueous solution is 10%. The protease is an alkaline protease, the phospholipase is a phospholipase D, and the mass ratio of the protease to the phospholipase is 5:1. The decomposition enzyme aqueous solution is added to the fresh latex. The total added mass of the protease and the phospholipase is 0.15wt% of the dry rubber content of the fresh latex. The mixture of the fresh latex and the decomposition enzyme aqueous solution is stirred and left for 2h to obtain a first latex.

[0046] (2) Add dimethyldiallyl ammonium chloride, a quaternary ammonium salt flocculant, to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. The added mass of dimethyldiallyl ammonium chloride is 0.3 wt% of the mass of the fresh latex.

[0047] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0048] Example 3

[0049] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0050] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0051] (2) Add dimethyldiallyl ammonium chloride and dimethylamine / epichlorohydrin polymer to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. Dimethyldiallyl ammonium chloride and dimethylamine / epichlorohydrin polymer are used as flocculants, and the mass ratio of dimethyldiallyl ammonium chloride to dimethylamine / epichlorohydrin polymer is 4:1. The added mass of the flocculant is 0.4wt% of the fresh latex content.

[0052] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0053] Example 4

[0054] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0055] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0056] (2) Add acrylamide / dimethyldiallyl ammonium chloride to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. Wherein, acrylamide / dimethyldiallyl ammonium chloride is used as a flocculant, and the added mass of the flocculant is 0.4wt% of the fresh latex content.

[0057] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0058] Example 5

[0059] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0060] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0061] (2) Adding dicyandiamide / epichlorohydrin polymer to the first latex at room temperature of 21 degrees Celsius, stirring evenly, and standing for 30 minutes. The dicyandiamide / epichlorohydrin polymer is used as a flocculant, and the added mass of the flocculant is 1.0wt% of the fresh latex content.

[0062] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0063] Example 6

[0064] This embodiment uses fresh latex from Hevea brasiliensis produced in Hainan, with a dry rubber content of 27wt% and an ammonia content of 0.5wt%.

[0065] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0066] (2) Adding dicyandiamide / formaldehyde polymer to the first latex at room temperature of 21 degrees Celsius, stirring evenly, and standing for 30 minutes. The dicyandiamide / formaldehyde polymer is used as a flocculant, and the added mass of the flocculant is 2.0wt% of the fresh latex content.

[0067] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0068] Example 7

[0069] Adopt the fresh latex that derives from the Hevea brasiliensis tree produced in Hainan, the dry rubber content is 27wt%, and the ammonia content is 0.3wt%. In the present embodiment, the fresh latex total solid is diluted with water to a dry rubber content of 17wt%.

[0070] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.05 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0071] (2) Add dimethyldiallyl ammonium chloride, a quaternary ammonium salt flocculant, to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. The added mass of dimethyldiallyl ammonium chloride is 0.5 wt% of the mass of the fresh latex.

[0072] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0073] Example 8

[0074] Fresh latex from Hevea brasiliensis produced in Hainan is used, with dry rubber content of 27wt% and ammonia content of 0.4wt%. The latex is concentrated to a concentration of 50wt% by sedimentation centrifugation.

[0075] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.5 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0076] (2) Add dimethyldiallyl ammonium chloride, a quaternary ammonium salt flocculant, to the first latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. The added mass of dimethyldiallyl ammonium chloride is 0.3 wt% of the mass of the fresh latex.

[0077] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber pellets are sent to an oven and dried at 90 degrees Celsius to obtain the low Mooney high-strength natural rubber of this embodiment.

[0078] Comparative Example 1

[0079] The present embodiment adopts fresh latex derived from Hevea brasiliensis produced in Hainan to prepare traditional acid flocculated natural rubber, wherein the dry rubber content of the fresh latex is 27wt%, and the ammonia content is 0.5wt%.

[0080] (1) A formic acid solution with a concentration of 3 wt% is prepared, and the formic acid solution is added to the fresh latex and stirred evenly, and the coagulation is left to mature for two hours. The mass of the formic acid added to the fresh latex is 0.3 wt% of the fresh latex content.

[0081] (2) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber granules are sent to an oven and dried at 90 degrees Celsius to obtain the natural rubber of this embodiment.

[0082] Comparative Example 2

[0083] The present embodiment adopts fresh latex derived from the Hevea brasiliensis tree produced in Hainan to prepare acid flocculated low-protein natural rubber. Wherein, the dry rubber content of the fresh latex is 27wt%, and the ammonia content is 0.5wt%.

[0084] (1) A protease aqueous solution is prepared with alkaline protease having an activity of 100000 u / g as a solute, wherein the mass fraction of the enzyme in the protease aqueous solution is 10%. The protease aqueous solution is added to fresh latex. The amount of the protease added is 0.15 wt % of the dry rubber content of the fresh latex. The mixture of the fresh latex and the protease aqueous solution is stirred and left to stand for 2 hours to obtain a first latex.

[0085] (2) preparing a formic acid solution with a concentration of 3 wt%, adding the formic acid solution to the fresh latex and stirring evenly, and leaving the coagulation for two hours to mature. The mass of the formic acid added to the fresh latex is 0.3 wt % of the fresh latex content.

[0086] (3) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber granules are sent to an oven and dried at 90 degrees Celsius to obtain the natural rubber of this embodiment.

[0087] Comparative Example 3

[0088] The present embodiment adopts fresh latex derived from Hevea brasiliensis produced in Hainan to prepare quaternary ammonium salt flocculated natural rubber, wherein the dry rubber content of the fresh latex is 27wt%, and the ammonia content is 0.5wt%.

[0089] (1) Add bis(dimethyldiallyl)ammonium chloride, a quaternary ammonium salt flocculant, to fresh latex at room temperature of 21 degrees Celsius, stir evenly, and leave for 30 minutes. The added mass of bis(dimethyldiallyl)ammonium chloride is 0.5 wt% of the fresh latex.

[0090] (2) The curd is fished out, creped, granulated, washed with water, and after dripping, the rubber granules are sent to an oven and dried at 90 degrees Celsius to obtain the natural rubber of this embodiment.

[0091] Comparative Example 4

[0092] Domestic environmentally friendly cigarette tablets.

[0093] Performance Testing

[0094] The natural rubber prepared in the above-mentioned Examples 1-8 and Comparative Examples 1-4 was sampled, and each sample was placed on a constant speed roller to be uniformly rolled, and the uniformly rolled rubber was subjected to Mooney test using a Songshu MV-2000 rubber Mooney tester. In addition, the natural rubber obtained in Examples 1-8 and Comparative Examples 1-4 was mixed according to the "NY / T1403-2007 Natural Rubber Evaluation Method" to obtain samples after flocculation, and then the physical properties of each sample were tested. The test results are shown in Table 1:

[0095] Table 1 Performance test data of each embodiment and comparative example

[0096] 100% elongation / MPa 300% elongation / MPa Tensile strength / MPa Fracture growth rate / % Mooney value Example 1 1.8 7.8 30.3 688.5 44.7 Example 2 1.5 6.1 26.6 663.7 35.6 Example 3 1.7 7.5 29.3 683.7 40.8 Example 4 1.8 8 29.6 671.8 62.2 Example 5 1.7 6.8 29.5 698.8 44.2 Example 6 1.9 7.7 29.3 673.6 63.5 Example 7 1.6 7.2 28.5 671.2 48.1 Example 8 1.5 6.4 27.3 662.3 42.8 Comparative Example 1 1.9 8.3 29.2 647.6 75.5 Comparative Example 2 1.7 7.5 28.2 665.8 74.1 Comparative Example 3 1.8 7.6 29.7 675.1 86.6 Comparative Example 4 1.6 7 30.5 701.7 92

[0097] As can be seen from Table 1, the Mooney values ​​of the natural rubber obtained in Examples 1-8 are 30-65, which are significantly smaller than those of the natural rubber obtained in Comparative Examples 1 to 4. Among them, the natural rubber obtained in Example 2 is the most obvious. In addition, the physical properties of the natural rubber obtained in Examples 1-8 after kneading are basically the same as those of Comparative Examples 1-4. In particular, the fracture growth rate of the natural rubber of Examples 1-8 after kneading is significantly improved compared with that of Comparative Example 1. It can be seen that the present invention, through the combined action of decomposing enzymes and flocculants, enables the prepared natural rubber to maintain or even improve the physical properties while significantly reducing the Mooney value, thereby providing a low-Mooney high-performance natural rubber.

[0098] The above contents are merely examples and illustrations of the structure of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and these obvious replacement forms all belong to the protection scope of the present invention.

Claims

1. A low Mooney high performance natural rubber, characterized in that: The invention is prepared from the following components: fresh latex, decomposing enzyme and flocculant; Based on the mass of the fresh latex, the mass of the decomposition enzyme is 0.05% to 0.5% of the mass of the dry rubber of the fresh latex, and the decomposition enzyme includes at least one of a protease or a phospholipase; The mass ratio of the fresh latex to the flocculant is: 100:(0.3-2.0), and the flocculant is a cationic quaternary ammonium salt.

2. The low Mooney high performance natural rubber according to claim 1, characterized in that: The flocculant is selected from at least one of polydimethyldiallyl ammonium chloride, acrylamide / dimethyldiallyl ammonium chloride copolymer, pyridinium quaternary ammonium salt type cationic polyacrylamide, modified urea-formaldehyde resin quaternary ammonium salt, dicyandiamide / epichlorohydrin polymer, dicyandiamide / formaldehyde polymer, and dimethylamine / epichlorohydrin polymer.

3. The low Mooney high performance natural rubber according to claim 2, characterized in that: The flocculant consists of dimethyldiallylammonium chloride and dimethylamine / epichlorohydrin polymer.

4. The low Mooney high performance natural rubber according to claim 1, characterized in that: The decomposing enzyme comprises protease and phospholipase, and the mass ratio of the protease to the phospholipase is 5:

1.

5. The low Mooney high performance natural rubber according to claim 1, characterized in that: The protease is alkaline protease, and the phospholipase is phospholipase D.

6. A method for preparing the low Mooney high-performance natural rubber according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. The decomposing enzyme is added to the fresh latex, stirred, and the fresh latex is hydrolyzed to obtain the first latex; S2. adding a flocculant to the first latex, stirring, and allowing to stand to obtain a latex clot; S3. The latex coagulates are fished out, creped, granulated, washed with water, and dried after dripping to obtain natural rubber.

7. The method for preparing low Mooney high performance natural rubber according to claim 6, characterized in that: In S1, the step of adding the decomposing enzyme to the fresh latex comprises: The decomposition enzyme is added to water to prepare a decomposition enzyme aqueous solution.

8. The method for preparing low Mooney high performance natural rubber according to claim 7, characterized in that: In the decomposition enzyme aqueous solution, the mass fraction of the decomposition enzyme is 10%.

9. The method for preparing low Mooney high performance natural rubber according to claim 6, characterized in that: The activity of the degrading enzyme is at least 100,000 u / g.

10. The method for preparing low Mooney high performance natural rubber according to claim 6, characterized in that: The dry rubber content of the fresh latex is 17-50wt%, and the ammonia content is within 0.5wt%.

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