CN111171415B - Large-size non-standard SBR (styrene butadiene rubber) blended closed-cell secondary die-pressing foaming material and preparation method thereof - Google Patents

Abstract

The invention discloses a large-size non-standard SBR (styrene butadiene rubber) blended closed-cell secondary die-pressing foaming material and a preparation method thereof.A plurality of sub-formulas, such as synthetic rubber, black smoke rubber master batch and natural rubber pre-mixed rubber formulas, are adopted, and the formulas are combined with other raw materials and a process manufacturing scheme is repeatedly adjusted to prepare a foaming body with the size of 1720X 7500mm 62mm; the invention solves the problems of scorching prevention and primary vulcanization into a vulcanization foaming system mainly comprising secondary foaming during the processes of banburying, mixing and extrusion of colloid, enhances the heat conduction uniformity of the foaming body, the pore diameter structure uniformity of the foaming body, the compactness of the inner layer and the outer layer, the physical property consistency, the hardness and the stable balance of various curves of vulcanization foaming in the vulcanization foaming stage, and realizes the breakthrough of large-specification foaming size under the physical property characteristic of the foaming body with the conventional specification of 1300mm, 3300mm and 50mm.

Description

Large-size non-standard SBR (styrene butadiene rubber) blended closed-cell secondary die-pressing foaming material and preparation method thereof

Technical Field

The invention relates to the technical field of polymer preparation, in particular to a large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material and a preparation method thereof.

Background

At present, the specification of the foaming material on the market is generally 1300mm × 3300mm × 50mm, for example, a patent number of CN201110346009.4 applied by the applicant earlier discloses an environment-friendly styrene butadiene rubber closed-cell secondary foaming material and a preparation method thereof, the foaming material with the specification of 1300mm × 3300mm × 50mm produced by the method is formed into large-scale production, and is widely applied to the fields of shoe materials, bags, yoga mats, sports protectors, outdoor tents, outdoor equipment, large-scale military and civil important electronics, mechanical equipment, rain prevention, dust prevention, diving surfing clothes, building heat insulation and the like.

Then, the size is needed to be large for many purposes, glue is needed to be used for connection in the middle of foaming specifications with conventional sizes, and double-sided composite cloth or foaming sheet surface coating treatment is needed, glue joints are increased, the requirements on cutting quantity and physical properties in the subsequent processing process are greatly limited, and glue joints need to be avoided, so that the generated loss is increased, the utilization rate is seriously insufficient, and the waste is large; at present, the size specification of the leading product in the market at home and abroad is 1300mm by 3300mm by 50mm, and the requirement cannot be met.

In order to produce a foamed product with a larger specification, the applicant tries to expand the addition amount of the existing formula according to the proportion of the formula to produce the foamed product with the larger specification, but the performances of the foamed product produced according to the existing formula, such as vulcanization, foaming heat conduction uniformity, hardness, foaming aperture uniformity, density of inner and outer layers, physical property consistency, stable balance of a vulcanization curve and a foaming curve, and the like, cannot meet the product requirements.

Disclosure of Invention

The embodiment of the application solves the problem that the foaming material in the prior art is small in specification and cannot meet the use requirement by providing the preparation method of the large-size non-standard SBR blended closed-cell secondary die-pressing foaming material, and realizes breakthrough of large-size foaming size under the physical property characteristic of the foaming body with the conventional specification of 1300mm × 3300mm × 50mm.

The embodiment of the application provides a large-size non-standard SBR rubber blending closed-cell secondary die-pressing foaming material which comprises the following raw materials in parts by weight:

further, the synthetic glue comprises:

further, the natural rubber premix comprises:

100 portions of natural rubber

1-2 parts of stearic acid.

Further, the black tobacco gum base comprises:

further, the mixed oil T is prepared from 1# environment-friendly aromatic hydrocarbon oil, 4006# naphthenic oil according to the weight ratio of 1:2, and mixing the components in a ratio of 2.

A preparation method of a large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material comprises the following steps:

(1) Preparation of Mixed oil T

Preheating oil barrels filled with 1# environment-friendly aromatic hydrocarbon oil and 4006# naphthenic oil respectively, pumping the 1# environment-friendly aromatic hydrocarbon oil and 4006# naphthenic oil into a stirring barrel in advance according to the proportion of 1:2, and uniformly stirring in the stirring barrel to obtain mixed oil T;

(2) Preparation of Natural rubber premix

Mixing and masticating natural rubber and stearic acid to obtain natural rubber colloid; putting the natural rubber colloid into an open mill for milling to obtain natural rubber premixed rubber;

(3) Preparation of Nicotiana tabacum Gum

Mixing and banburying stearic acid, a dispersing agent AT-B, an anti-aging agent 4010NA, microcrystalline paraffin LY-1, carbon black N330, carbon black N550 and carbon black N774, adding mixed oil T for banburying again, and then adding natural rubber premix rubber for mixing to obtain black smoke rubber master batch;

(4) Preparation of synthetic rubber

Sequentially putting stearic acid, a dispersing agent AT-B, microcrystalline paraffin LY-1, an anti-aging agent 2246, an anti-aging agent PPD-B, an anti-aging agent FR, palm oil ointment, activated calcium carbonate, PEG4000 polyethylene glycol, zinc stearate, calcium stearate, activated zinc oxide, activated magnesium oxide and vaseline into an internal mixer for banburying uniformly, and then putting styrene butadiene rubber, natural rubber premixed rubber and black smoke rubber masterbatch for mixing;

(5) Preparation of Mixed gums

Fully stirring insoluble sulfur glue serving as a vulcanizing agent, p-tert-octylphenol formaldehyde resin SP-1045 serving as a vulcanizing agent, an accelerator DM, argil, light calcium carbonate, magnesium strong powder and a foaming agent DPT, adding mixed oil T, banburying uniformly, then adding synthetic rubber, mixing, then carrying out banburying on the accelerator M, the accelerator DPG, the accelerator DTDM, the accelerator CZ, the accelerator TMTM, the accelerator DETU, the foaming agent AC6000 and the foaming agent OBSH, adding the mixed oil T again, mixing, standing and cooling to obtain mixed rubber;

(6) Extrusion

(7) First in-mold closed cell foaming

Putting the material obtained in the step (6) into an in-mold foaming mold of an oil pressure vulcanizing machine, wherein the specification of the in-mold foaming mold is 1150mm × 3500mm × 22mm, the vulcanization temperature is 135 +/-5 ℃, the holding time is 45-50 minutes, and the pressure is relieved to obtain a high-elasticity foaming body, namely 1300mm × 5300mm × 45mm, and trimming the high-elasticity foaming body;

(8) Second in-mold closed cell foaming

Filling the high-elasticity foaming body into a foaming machine die 1600mm multiplied by 7200mm multiplied by 60mm for foaming, keeping the foaming temperature at 168 +/-5 ℃ for 25-35 minutes, and releasing the pressure to obtain the high-elasticity foaming body;

(9) Shaping

Naturally cooling the foaming body at room temperature, and warehousing or processing and molding after the product is sufficiently cooled and contracted.

Further, a preparation method of the large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material, wherein the (1) preparation of the mixed oil T comprises the following specific steps:

respectively preheating oil drums filled with the 1# environment-friendly aromatic hydrocarbon oil and the 4006# naphthenic oil to 50 ℃, then pumping the 1# environment-friendly aromatic hydrocarbon oil and the 4006# naphthenic oil into a stirring barrel in advance according to the proportion of 1:2, and stirring for 2 hours at the rotating speed of 10 revolutions per minute to obtain the mixed oil T.

Further, the step (2) of preparing the natural rubber premix comprises the following specific steps:

putting natural rubber and stearic acid into an internal mixing chamber for mastication, pressing down by a heavy hammer for 4 times, mixing for 500-600 seconds or pouring at 130 +/-3 ℃ to obtain natural rubber colloid, putting the natural rubber colloid into an open mill, adjusting the gap of a roller to 2mm, mixing for 500-600 seconds, passing through the roller for two times with the thickness of 5mm, continuously passing cooling water through the inner wall of the roller, controlling the temperature to 90 +/-5 ℃, and standing to obtain the natural rubber premixed rubber.

Further, the extrusion process (2) comprises the following specific steps:

adjusting the roller clearance of the open mill to 8mm for open milling and turnover for 500 seconds, continuously introducing cooling water into the inner wall of the roller, controlling the temperature to be 80 +/-5 ℃, controlling the diameter to be 250mm, and controlling the diameter length-diameter ratio to be 1: extruding by an 8-hot-feeding single-screw extruder at the speed of 1-2 meters per minute, extruding at the temperature of 80 +/-5 ℃, automatically cutting a film output of a film output conveyor, and standing and cooling to obtain the film.

One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

1. through years of experimental research, the applicant improves a single formula of conventional-size foaming into a formula consisting of four formulas, namely three formulas of natural rubber premixed rubber, black tobacco rubber master batch and synthetic rubber, is specially customized and processed for the invention, is different from main rubber raw materials in other inventions, journals and documents, prepares synthetic rubber by matching the three types of rubber according to parts by weight according to a vulcanization and foaming system of a foaming material, and can stably obtain the large-size non-standard SBR rubber closed-cell blended secondary die-pressing foaming material after subsequent process processing.

2. The natural rubber is pre-mixed and uniformly dispersed, and the mixed rubber is uniformly dispersed by adopting higher temperature and time when being prepared.

3. In the prior art, the prepared foaming material has small specification, so the types and the quantity of the used auxiliary agents of a vulcanization system and a foaming system are small, the problem of scorching is not required to be considered, simultaneously, the added carbon black has few components, and the problems that the carbon black is easy to generate high temperature and the like due to strong friction force in rubber mixing are not required to be considered; in order to overcome the problems, the applicant of the invention develops the process and the formula of the black smoke rubber master batch by self, and independently mixes the black smoke rubber master batch, so that the problems that the black smoke rubber master batch reacts with a vulcanization auxiliary agent and a foaming auxiliary agent in the formula of a foaming material, and further the vulcanization and foaming are advanced to enter a scorching period and the like are avoided; the technical effect of providing guarantee for subsequent extrusion and foaming processes is achieved.

4. The invention adopts a plurality of colloids which have different melting points and dispersion difficulty, and the problems of temperature, time, input sequence, reaction before each component and the like need to be fully considered during banburying, so that the invention adopts a plurality of formulas and combines with the specific process to ensure that the produced foaming material meets the production requirements.

5. According to the four compound formulas, the invention has more loose selection conditions of banburying, open milling, extrusion, temperature and time in the process, more abundant safety and stability prevention of scorching in advance and better effect, and the temperature, time, vulcanization curve and foaming curve integrating degree and selection condition range in the vulcanization and foaming process are more in line with the mass production requirement of the foaming body with large size.

6. According to the invention, the natural rubber premix, the black smoke rubber masterbatch and the synthetic rubber are respectively prefabricated, so that the modification treatment of the natural rubber, the styrene butadiene rubber and the like is realized, and the physical property characteristic effect of different types of rubber seeds which can be retained by simple mixing and banburying is obviously better. The rubber mixture is more static energy-efficient no matter the dispersibility, the saturation and the pre-crosslinking effect.

7. The temperature and time of the vulcanization system and the foaming system are reasonably adjusted, so that the primary vulcanization is mainly characterized; the secondary foaming is mainly characterized in that the superposition interval of a vulcanization curve and a foaming curve is wide, and the heat conduction uniformity of a steam hot plate and the volume, the vulcanization degree and the foaming degree of an oil pressure die assembly external pressure and an expansion internal pressure of colloid in a die obviously reach the complementary synergistic effect of the process and the formula as much as possible.

8. The invention selects four compound formulas to carry out trial production through process combination and successfully develops a practical complete formula system and process meeting the requirement of the foaming body with larger size, solves the problems of scorching prevention and primary vulcanization and secondary foaming of colloid during banburying, mixing and extrusion processes, enhances the heat conduction uniformity of the foaming body, the pore structure uniformity of the foaming body, the density of the inner layer and the outer layer, the physical property consistency, the hardness and the stability and balance of curves of vulcanization foaming in the vulcanization foaming stage, realizes the breakthrough of large foaming size under the physical property characteristic of the foaming body with conventional specification of 130mm, 330mm, 50mm, and simultaneously obtains the foaming body with 1720, 7500mm, 62mm size.

Detailed Description

In order to better understand the technical solutions, the technical solutions will be described in detail with reference to the description and the specific embodiments.

Example 1:

the formulation of this example is shown in table 1:

TABLE 1

A preparation method of a large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material comprises the following specific steps:

(1) Preparing mixed oil T:

preheating an oil drum: the oil drum is transported to a customized electric heating temperature control preheating box by a forklift, and the oil drum is clamped by a slow-speed rotating heating clamping and forking clamp to preheat to 50 ℃ in advance.

Pumping oil into a stirring barrel:

a. customization of 1m ³ The automatic oil pumping and stirring barrel is a double-layer barrel wall, and an electric heating wire and an automatic temperature control heating switch are wound outside the automatic oil pumping and stirring barrel; helical blades are adopted in the stirring barrel, and the blades are hollow and can be heated by an electric heating wire.

b. Manual ball with custom beltDiameter of valve 1 ¹ / ₂ The stainless steel pipe head MB (1 inch and half) with the length of 1000mm is connected with a rubber hose for the self-priming centrifugal oil well pump.

c. Inserting a customized pipe head MB into a barreled softened oil barrel, respectively pumping two crude oils of the 1# environment-friendly aromatic hydrocarbon oil and the 4006# naphthenic oil into a stirring barrel in advance according to the proportion of 1:2, and uniformly stirring and premixing for 2 hours at a rotating speed of 10 revolutions per minute to obtain mixed oil T;

(2) Preparing natural rubber premix rubber:

a. 100 parts of natural rubber and 1 part of stearic acid are put into an internal mixing chamber, a heavy hammer is pressed down for 4 times (150 seconds for the first time, and 120 seconds for each of the second time to the 4 th time, the heavy hammer is lifted and stays for 15 seconds at intervals, and the air pressure is 7.5kg/cm ² Continuously introducing cooling water into a blade shaft, a wall of the mixing chamber and an inner cavity of a heavy hammer of the ML-75 mixer during the mixing period) mixing for 500-600 seconds or pouring materials at 130 +/-3 ℃;

b. b, putting the material obtained in the step a into an open mill, adjusting the gap of a roller to 2mm, carrying out open milling and turnover for 500-600 seconds, then carrying out twice through the roller with the thickness of 5mm, continuously introducing cooling water into the inner wall of the roller, controlling the temperature to be 90 +/-5 ℃, and standing for 24 hours to obtain natural rubber premixed rubber;

(3) Preparing a black tobacco gel master batch:

a ¹ adding 1-2 parts of stearic acid, 1-2 parts of a dispersing agent AT-B, 0.5-1 part of an anti-aging agent 4010NA, 0.5-1 part of microcrystalline wax, 15-25 parts of carbon black N330, 10-15 parts of carbon black N550 and 15-20 parts of carbon black N774 into an internal mixer according to the weight part of the formula, adding 25-30 parts of mixed oil T into an automatic oil pumping spiral blade stirring barrel MA after a heavy hammer keeps ascending state and stirring uniformly, stirring uniformly by the internal mixer again, adding 100 parts of natural rubber premixed rubber, pressing the heavy hammer for 5 times (pressing for 200 seconds for the first time and pressing for 90 seconds from the second time to the fifth time, keeping the heavy hammer ascending for 15 seconds, keeping the air pressure AT 7.5kg/cm < 2 >, continuously introducing cooling water into the blade shaft, the internal mixing chamber wall and the internal cavity of the internal mixer during mixing), and mixing for 620 seconds or pouring AT 130 +/-3 ℃;

b ¹ adjusting the roller clearance of the open mill to 8mm for 500 seconds, then passing through the roller twice with a thickness of 2mm and passing through the roller twice with a thickness of 5mm, continuously passing cooling water through the inner wall of the roller, controlling the temperature to be 80 +/-5 ℃, and floating according to the weight part of the formulaObtaining black tobacco gum mother rubber through dynamic cutting and standing for 24 hours;

(4) Preparing synthetic glue:

a ² according to the weight portion of the formula, 2-3 portions of stearic acid, 2-3 portions of dispersant AT-B, 1-2 portions of microcrystalline paraffin, 2246-2 portions of phenol antioxidant, 1-2 portions of p-phenylenediamine antioxidant PPD-B, 1-2 portions of antioxidant FR, 20-30 portions of palm oil paste, 10-20 portions of active calcium carbonate, 3-6 portions of PEG4000 polyethylene glycol, 3-6 portions of zinc stearate, 8-15 portions of calcium stearate, 20-30 portions of active zinc oxide, 5-10 portions of active magnesium oxide and 5-10 portions of vaseline are put into an internal mixer in sequence, 100 portions of styrene butadiene rubber, 30-50 portions of natural rubber premixed rubber and 30-50 portions of black smoke rubber are put into the internal mixer after the internal mixing blade shaft rotates and is uniformly stirred in an ascending state, a heavy hammer is pressed for 6 times (the first time is pressed for 200 seconds, the second time is pressed for the second time to the fifth time, the ascending time is kept for 15 seconds, and the air pressure is 7.5kg/cm ² Continuously introducing cooling water into a blade shaft, a wall of the internal mixing chamber and an inner cavity of a heavy hammer of the internal mixer during mixing) for mixing for 620 seconds or pouring at 130 +/-3 ℃;

b ² adjusting the gap between rollers of the open mill to 8mm for open milling and turnover for 500 seconds, then performing thin passing twice with the thickness of 2mm, performing thick passing twice with the thickness of 5mm, continuously passing cooling water through the inner wall of the roller, controlling the temperature to be 80 +/-5 ℃, weighing and standing for 24 hours to obtain synthetic rubber;

(5) Preparation of Mixed gums

a ³ Continuously introducing cooling water into an internal mixer, continuously introducing 1-1.8 parts of vulcanizing agent insoluble sulfur medical adhesive, 0.3-0.5 part of vulcanizing agent p-tert-octylphenol formaldehyde resin SP-1045, 0.3-0.5 part of accelerator 1DM0.3-0.6 part of pottery clay, 80-100 parts of light calcium carbonate, 15-20 parts of magnesium powder, 2-3 parts of foaming agent DPT, using an automatic oil pumping spiral blade stirring barrel, adding 25-35 parts of mixed oil T, uniformly stirring by the internal mixer, then adding 100 parts of synthetic rubber for mixing, pressing by a heavy hammer for 4 times (first pressing for 200 seconds, second pressing for 90 seconds, stopping for 15 seconds each time, and keeping the air pressure for 7.5kg/cm < 2 >, continuously introducing cooling water into a blade shaft of the internal mixer, a wall of the internal cavity of the internal mixer and a heavy hammer during mixing) for mixing for 515 seconds or at the temperature of 120 +/-5 ℃, and continuously introducing 0.2-0.4 parts of accelerator M, 0.2-0.3 parts of accelerator DPG, 0.2-0.3 parts of accelerator DTDM, 0.3 parts of accelerator and 0.3 parts of CZ,0.1-0.2 part of accelerant TMTM, 0.1-0.2 part of accelerant DETU, 8-10 parts of foaming agent AC6000 and 1-2 parts of foaming agent OBSH are put into an internal mixer, 8-10 parts of mixed oil T is added into an automatic oil pumping helical blade stirring barrel, and the mixture is mixed with the sizing material mixture through the internal mixer and pressed down for 3 times (pressed down for 120 seconds for the first time and pressed down for 70 seconds for the second time to the third time respectively, the weight rises and stays for 15 seconds each time, the air pressure is 7.5kg/cm < 2 >, and cooling water is continuously introduced into a blade shaft, an internal mixing chamber wall and an internal cavity of the internal mixer during mixing) for 290 seconds or the temperature reaches 120 +/-5 ℃ for discharging;

b ³ adjusting the roller clearance of an open mill to 8mm for open milling and turnover milling for 500 seconds, then performing thin milling twice for 2mm, and performing thick milling twice for 5mm, continuously introducing cooling water to the inner wall of the roller, controlling the temperature to 80 +/-5 ℃ for open milling, adjusting the roller clearance of a calender to 0.5-1 mm for calendering, standing and cooling to obtain mixed rubber;

(6) Extruding:

the roller clearance of the open mill is adjusted to 8mm open mill and is turned over for 500 seconds, cooling water is continuously introduced into the inner wall of the roller, the temperature is controlled to be 80 +/-5 ℃, the diameter is 250mm, and the diameter length-diameter ratio is 1:8 hot feed single screw extruder extrudes at the speed of 1 ~ 2 meters per minute, and control by temperature change 80 ℃ + -5 ℃ is extruded, decides out a piece conveyer automatically and goes out the piece, and the many rollers of automatic rising weigh platform weighs and will bear the weight of the dull and stereotyped of film and put into the cold work or material rest of multilayer and stew the cooling according to every layer of difference in height, obtains the film.

(7) First in-mold closed-cell foaming:

accurately weighing the film by an electric control hydraulic lifting electronic weighing platform, filling the film into an in-mold foaming mold of an oil pressure vulcanizing machine with the corresponding quantity of 2000 tons of 2 cylinders, wherein the specification of the in-mold foaming mold is 1150mm, 3500mm, 22mm, the vulcanization temperature is 135 +/-5 ℃, the holding time is 45-50 minutes, and the high-elasticity foaming body is obtained by pressure relief and trimmed with the specification of 1300mm, 5300mm, 45mm;

(8) Second in-mold closed cell foaming

Filling the high-elasticity foaming body obtained in the previous procedure into a corresponding 400 ton oil pressure foaming machine mould with the number of 8 cylinders, wherein the mould is 1600mm, 7200mm, 60mm, foaming temperature is 168 +/-5 ℃, keeping time is 25-35 minutes, and pressure relief is carried out to obtain the high-elasticity foaming body, 1950mm, 8500mm, 68mm; cooling for half an hour and then shrinking the sponge to 1780mm 7800mm 65mm;

(9) Shaping

Naturally cooling the foamed body obtained in the previous step at room temperature for 7-10 days, and warehousing or processing and molding after the product is fully cooled and shrunk by 1720mm x 7500mm x 62mm.

Comparative example 1

Comparative example 1 adopts the physical property data provided in the preparation method of the environment-friendly styrene butadiene rubber closed-cell secondary foam material with the application number of CN 201110346009.4;

physical property comparison ratios of the foamed material of example 1 and the foamed material of comparative example 1 are shown in table 2 below, environment-friendly PAHS polycyclic aromatic hydrocarbon test results of the foamed material of example 1 are shown in table 3, and halogen detection results of the foamed material of example 1 are shown in table 4 below:

TABLE 2

TABLE 3

Test item	Content (mg/kg)	Method detection limit (mg/kg)
			Fluorine (F)	N.D	50
Chlorine (C1)	N.D	50
			Bromine (Br)	N.D	50
Iodine (I)	N.D	50

TABLE 4

(Note: 1.mg/kg = PPM = parts per mileon; 2.N.D = not Detected (less than detection limit of method)

In conclusion, the foamed material produced by the invention can keep the physical index of the conventional foaming specification on the premise of keeping the large size, greatly reduces waste by cutting and typesetting when the material is used for processing finished products such as garments, bags, mats and the like, and reduces the influence of glue bonding parts on the physical property.

The above description is only an embodiment utilizing the technical content of the present disclosure, and any modification and variation made by those skilled in the art can be covered by the claims of the present disclosure, and not limited to the embodiments disclosed.

Claims (7)

1. A large-size non-standard SBR (styrene butadiene rubber) blended closed-cell secondary die-pressing foaming material is characterized by comprising the following raw materials in parts by weight:

the synthetic glue comprises:

the mixed oil T is prepared from 1# environment-friendly aromatic hydrocarbon oil and 4006# naphthenic oil according to the weight ratio of 1:2, and mixing the components in a ratio of 2.

2. The large-size non-standard SBR rubber blended closed-cell secondary molding foaming material of claim 1, wherein the natural rubber pre-blended rubber comprises:

100 portions of natural rubber

1-2 parts of stearic acid.

3. The large-size non-standard SBR rubber blended closed-cell secondary molding foaming material of claim 2, wherein the black smoke rubber matrix comprises:

4. a preparation method of a large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material is characterized by comprising the following steps:

(1) Preparation of Mixed oil T

Preheating oil barrels filled with 1# environment-friendly aromatic hydrocarbon oil and 4006# naphthenic oil respectively, pumping the 1# environment-friendly aromatic hydrocarbon oil and 4006# naphthenic oil into a stirring barrel in advance according to the proportion of 1:2, and uniformly stirring in the stirring barrel to obtain mixed oil T;

(2) Preparation of Natural rubber premix

Mixing and masticating natural rubber and stearic acid to obtain natural rubber colloid; putting the natural rubber colloid into an open mill for milling to obtain natural rubber premixed rubber;

(3) Preparation of Nicotiana tabacum Gum

Mixing and banburying stearic acid, a dispersing agent AT-B, an anti-aging agent 4010NA, microcrystalline paraffin LY-1, carbon black N330, carbon black N550 and carbon black N774, adding mixed oil T for banburying again, and then adding natural rubber premix rubber for mixing to obtain black smoke rubber master batch;

(4) Preparation of synthetic rubber

Sequentially putting stearic acid, a dispersing agent AT-B, microcrystalline paraffin LY-1, an anti-aging agent 2246, an anti-aging agent PPD-B, an anti-aging agent FR, palm oil ointment, activated calcium carbonate, PEG4000 polyethylene glycol, zinc stearate, calcium stearate, activated zinc oxide, activated magnesium oxide and vaseline into an internal mixer for banburying uniformly, and then putting styrene butadiene rubber, natural rubber premixed rubber and black smoke rubber masterbatch for mixing;

(5) Preparation of Mixed gums

Fully stirring insoluble sulfur glue of a vulcanizing agent, p-tert-octylphenol formaldehyde resin SP-1045 of the vulcanizing agent, an accelerator DM, argil, light calcium carbonate, magnesium powder and a foaming agent DPT, adding mixed oil T, banburying uniformly, then adding synthetic rubber, banburying, then adding the accelerator M, the accelerator DPG, the accelerator DTDM, the accelerator CZ, the accelerator TMTM, the accelerator DETU, the foaming agent AC6000 and the foaming agent OBSH, banburying again with the mixed oil T, standing and cooling to obtain mixed rubber;

(6) Extrusion

(7) First in-mold closed cell foaming

Putting the material obtained in the step (6) into an in-mold foaming mold of an oil pressure vulcanizing machine, wherein the specification of the in-mold foaming mold is 1150mm × 3500mm × 22mm, the vulcanization temperature is 135 +/-5 ℃, the holding time is 45-50 minutes, and the pressure is relieved to obtain a high-elasticity foaming body, namely 1300mm × 5300mm × 45mm, and trimming the high-elasticity foaming body;

(8) Second in-mold closed cell foaming

Filling the high-elasticity foaming body into a foaming machine die 1600mm multiplied by 7200mm multiplied by 60mm for foaming, keeping the foaming temperature at 168 +/-5 ℃ for 25-35 minutes, and releasing the pressure to obtain the high-elasticity foaming body;

(9) Shaping

Naturally cooling the foaming body at room temperature, and warehousing or processing and molding after the product is sufficiently cooled and contracted.

5. The method for preparing the large-size non-standard SBR rubber blended closed-cell secondary molding foaming material according to claim 4, wherein the step (1) for preparing the mixed oil T comprises the following steps:

respectively preheating oil drums filled with the 1# environment-friendly aromatic hydrocarbon oil and the 4006# naphthenic oil to 50 ℃, then pumping the 1# environment-friendly aromatic hydrocarbon oil and the 4006# naphthenic oil into a stirring barrel in advance according to the proportion of 1:2, and stirring for 2 hours at the rotating speed of 10 revolutions per minute to obtain the mixed oil T.

6. The method for preparing the large-size non-standard SBR rubber blended closed-cell secondary die-pressing foaming material as claimed in claim 5, wherein the step (2) for preparing the natural rubber pre-mixed rubber comprises the following steps:

putting natural rubber and stearic acid into an internal mixing chamber for mastication, pressing by a heavy hammer for 4 times, mixing for 500-600 seconds or pouring at 130 +/-3 ℃ to obtain natural rubber colloid, putting the natural rubber colloid into an open mill, adjusting the gap of a roller to 2mm, mixing for 500-600 seconds, passing through the roller twice at a thickness of 5mm, continuously passing cooling water through the inner wall of the roller, controlling the temperature to 90 +/-5 ℃, and standing to obtain the natural rubber premixed rubber.

7. The method for preparing the large-size non-standard SBR rubber blended closed-cell secondary molding foaming material as claimed in claim 6, wherein the (2) extrusion process comprises the following steps:

adjusting the roller clearance of the open mill to 8mm for open milling and turnover for 500 seconds, continuously introducing cooling water into the inner wall of the roller, controlling the temperature to be 80 +/-5 ℃, controlling the diameter to be 250mm, and controlling the diameter length-diameter ratio to be 1: extruding by an 8-hot-feeding single-screw extruder at the speed of 1-2 meters per minute, extruding at the temperature of 80 +/-5 ℃, automatically cutting a film output of a film output conveyor, and standing and cooling to obtain the film.