Flame-retardant weather-resistant rare earth butyl isoprene rubber and preparation method thereof

Abstract

The invention relates to the technical field of high polymer materials, and discloses flame-retardant and weather-resistant rare earth butyl isoprene rubber and a preparation method thereof.The preparation method includes the steps that rare earth butyl isoprene rubber, calcium carbonate, modified silane, polyethylene, sulfur-containing modified polyurethane and an antioxidant 626 are added into a stirrer to be evenly mixed, melted and cooled, and the flame-retardant and weather-resistant rare earth butyl isoprene rubber is obtained; the flame-retardant and weather-resistant rare earth butyl isoprene rubber is obtained. In the melting process, isocyanate-terminated in the sulfur-containing modified polyurethane reacts with hydroxyl in modified silane, cross-linking is generated between the isocyanate-terminated in the sulfur-containing modified polyurethane and the hydroxyl in the modified silane, the isocyanate-terminated in the sulfur-containing modified polyurethane and the hydroxyl in the modified silane are wound with rare earth butyl isoprene rubber and polyethylene, so that the isocyanate-terminated in the sulfur-containing modified polyurethane and the hydroxyl in the modified silane are connected more tightly, and the tensile property is improved; a sulfur element, a phosphorus element, a silicon element and a nitrogen element in the sulfur-containing modified polyurethane and the modified silane have good flame-retardant effects and jointly form a flame-retardant system; and meanwhile, the rare earth butyl isoprene rubber disclosed by the invention also has relatively good weather resistance.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, in particular to a flame retardant and weather-resistant rare earth isoprene rubber and a preparation method thereof. Background Art

[0002] Rare earth butyl isoprene rubber is a high-performance synthetic rubber with similar molecular structure and properties to natural rubber. It can be widely used in tires, tapes, hoses and other fields, but its flame retardant effect is poor, which greatly limits its application. For example, patent CN106750635A discloses modified flame retardant isoprene rubber for cables and its preparation method. The modified flame retardant isoprene rubber prepared by this method has excellent flame retardancy. At the same time, the preparation method has the advantages of simple process and easy operation, but its stretching effect is not improved. Summary of the invention

[0003] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides a flame retardant and weather resistant rare earth isoprene rubber and a preparation method thereof, which has good flame retardancy, tensile strength and weather resistance.

[0004] (II) Technical solution To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a flame retardant and weather-resistant rare earth butadiene isoprene rubber, comprising the following weight components: 50-70 weight parts of rare earth butadiene isoprene rubber, 2-3 weight parts of calcium carbonate, 4-8 weight parts of modified silane, 12-18 weight parts of polyethylene, 4-7 weight parts of sulfur-modified polyurethane, and 0.2-0.4 weight parts of antioxidant 626.

[0005] Preferably, the preparation method of the sulfur-modified polyurethane is: (1) adding hexachlorocyclotriphosphazene and tetrahydrofuran solvent to a reactor, introducing nitrogen protection, stirring for 12-15 minutes, continuing to add p-hydroxybenzaldehyde and anhydrous potassium carbonate, heating to 65-80° C. and reflux reaction for 6-10 hours, filtering after completion, precipitating with petroleum ether, filtering by suction, washing with deionized water, and drying to obtain hexa(4-formylphenoxy)cyclotriphosphazene; (2) adding hexa(4-formylphenoxy)cyclotriphosphazene and 5-amino-2-mercaptobenzimidazole to an ethanol solvent, stirring for condensation reaction at 65-80°C for 3-5h, then adding diethyl phosphite for addition reaction at 70-90°C for 6-10h, and then distilling under reduced pressure after completion, washing with ether to obtain intermediate 1; (3) Add 2-5 parts by weight of purified polyurethane particles to dimethylformamide solvent, stir and dissolve at 85-110°C for 6-10 hours, dry after completion, continue to add 2-3 parts by weight of methyl methacrylate isothiocyanate, introduce nitrogen for protection, then add 0.01-0.03 parts by weight of triethylamine, and place in an oil bath at 50-70°C for 8-10 hours. After the reaction, wash with acetonitrile and dry to obtain olefinic polyurethane; (4) Add olefinated polyurethane to N,N-dimethylformamide solvent, stir and disperse, then add intermediate 1 and benzoin dimethyl ether photoinitiator, irradiate with 365 nm ultraviolet light at 25-40° C. for 3-5 h, centrifuge, wash and dry to obtain sulfur-modified polyurethane.

[0006] Preferably, the mass ratio of hexachlorocyclotrimer phosphazene, p-hydroxybenzaldehyde and anhydrous potassium carbonate in (1) is 1:2.1-3.4:0.01-0.03.

[0007] Preferably, the mass ratio of hexa(4-formylphenoxy)cyclotriphosphazene, 5-amino-2-mercaptobenzimidazole and diethyl phosphite in (2) is 1:1.2-1.4:1.1-1.5.

[0008] Preferably, in the (4), the ratio of olefinated polyurethane, intermediate 1, and benzoin dimethyl ether photoinitiator is 1.3-1.6:1:0.02-0.04.

[0009] Preferably, the preparation method of the modified silane is: S1. 8-14 parts by weight of allyl glycidyl ether, tetrahydrofuran solvent and 0.4-0.6 parts by weight of chloroplatinic acid are added to a reactor, activated at 40-60° C. for 32-50 min, and then 9-15 parts by weight of 1,1,3,3-tetramethyldisiloxane are added dropwise for 50-75 min, and the reaction is continued at 50-65° C. for 4-7 h. After the reaction is completed, the reaction is cooled to room temperature, an activated carbon adsorbent is added, ultrasonically shaken for 30-45 min, the catalyst chloroplatinic acid is removed, filtered, and rotary evaporated to obtain epoxy-modified siloxane; S2. Add epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst to N,N-dimethylformamide for ring-opening reaction at 70-95°C for 6-10 hours. After the reaction, dilute the precipitate, filter and wash to obtain modified silane.

[0010] Preferably, the mass ratio of epoxy-modified siloxane, intermediate 1, and tetrabutylammonium fluoride catalyst in S2 is 1.2-1.4:1:0.01-0.03.

[0011] Preferably, the preparation method of the flame retardant and weather-resistant rare earth butadiene isoprene rubber is as follows: rare earth butadiene isoprene rubber, calcium carbonate, modified silane, polyethylene, sulfur-modified polyurethane, and antioxidant 626 are added into a stirrer and mixed evenly, melted at a melting temperature of 190-200°C and a melting time of 20-40 minutes, and cooled to obtain the flame retardant and weather-resistant rare earth butadiene isoprene rubber.

[0012] 3. Beneficial technical effects The invention obtains flame-retardant and weather-resistant rare earth butadiene isoprene rubber by adding rare earth butadiene isoprene rubber, calcium carbonate, modified silane, polyethylene, sulfur-modified polyurethane and antioxidant 626 into a stirrer, mixing evenly, melting and cooling.

[0013] During the melting process, the terminal isocyanate in the sulfur-modified polyurethane reacts with the hydroxyl group in the modified silane to generate cross-linking between them, and is entangled with the rare earth butyl isoprene rubber and polyethylene to make the connection between them tighter and increase their tensile properties; the sulfur, phosphorus, silicon and nitrogen elements in the sulfur-modified polyurethane and the modified silane all have good flame retardant effects and together constitute a flame retardant system; at the same time, the rare earth butyl isoprene rubber of the present invention also has good weather resistance. DETAILED DESCRIPTION

[0014] Brief description of the production process of isoprene butadiene rubber: the carboxylic acid rare earth catalyst component and the aluminum component are respectively delivered by metering pumps, mixed through a venturi, and then mixed with the n-hexane solution of butadiene dissolved in the n-hexane preheater (precooler) and the n-hexane solution of isoprene, and then mixed with the aluminum catalyst at the bottom of the kettle and enter the first kettle.

[0015] In the polymerization kettle, the mixed solution is subjected to the action of the initiator at a certain temperature and pressure, causing polymerization of butadiene and isodiene to occur, generating high molecular weight butadiene and isodiene polymerization products.

[0016] The first kettle glue liquid comes out from the kettle outlet, enters the second kettle from the bottom of the second kettle to continue the reaction: then comes out from the kettle outlet of the second kettle, enters the third kettle from the bottom of the third kettle to continue the reaction: comes out from the kettle outlet of the third kettle, enters the fourth kettle to continue the reaction: when a certain viscosity and conversion rate are reached, the fourth kettle outlet pipeline (the inlet pipeline of the termination kettle) and the terminator enter the termination kettle from the bottom of the termination kettle for termination treatment: finally, the glue liquid comes out from the termination kettle outlet, enters the glue liquid tank through the glue liquid filter and the pressure control valve. After the terminated glue liquid enters the glue liquid tank, part of the unconverted butadiene and isoprene enter the butadiene storage tank through the tank pressure control regulating valve, the brine condensation cooler, and then is sent to the butadiene recovery tank area. After the glue liquid is mixed with each other in the tank according to the Mooney viscosity value, it is sent to the condensation kettle through the glue liquid pump. The qualified glue liquid is sprayed into the condensation kettle. Under the action of hot water, mechanical stirring and base steam heating, it is fully condensed to form particles, and the solvent oil solvent and a small amount of butadiene are evaporated. The gas evaporated from the kettle head includes water vapor, part of butadiene and most of the solvent oil solvent. The gas passes through two parallel circulating water condensation coolers, and the condensate enters the oil-water separator for oil-water separation. The solvent oil is sent to the solvent recovery tank area by an oil pump. The water is discharged from the bottom of the oil-water separation tank by the liquid level regulating valve and discharged into the ditch through the secondary purification separation tank. The glue particles at the bottom of the kettle and the circulating hot water are sent to the buffer of the glue washing station through the particle pump, and then the glue particles are separated by the No. 1 vibrating screen and sent to the glue washing tank. In the glue washing tank, the glue particles are washed with water at 40-60℃, and the washed glue particles and water are separated by the No. 2 vibrating screen, and the glue particles with 40-60% water content are sent to the extrusion drying station.

[0017] The water content of the rubber particles is reduced to 8-15% by extrusion, and then cut into strips and sent to the expansion dryer for heating and pressurization to achieve the purpose of expansion and internal steaming, remove most of the water in the rubber particles, and then send them to the horizontal infrared drying box for drying to reduce the water content of the rubber to below 0.75%. The qualified rubber strips are sent to the automatic weighing scale by the elevator for weighing and briquetting (25kg). The pressed rubber blocks are wrapped with film, put into paper bags, sealed and stored. Example 1

[0018] Hexachlorocyclotrimer phosphazene and tetrahydrofuran solvent were added to the reactor, nitrogen was introduced for protection, and the mixture was stirred for 12 minutes. p-hydroxybenzaldehyde and anhydrous potassium carbonate were added thereto, wherein the mass ratio of hexachlorocyclotrimer phosphazene, p-hydroxybenzaldehyde and anhydrous potassium carbonate was 1:2.1:0.01. The mixture was heated to 65° C. and refluxed for 6 hours. After the reaction was completed, the mixture was filtered, precipitated with petroleum ether, filtered, washed with deionized water, and dried to obtain hexa(4-formylphenoxy)cyclotriphosphazene. (2) Hexa(4-formylphenoxy)cyclotriphosphazene and 5-amino-2-mercaptobenzimidazole were added to an ethanol solvent, stirred for condensation reaction, and reacted at 65°C for 3 hours. Then, diethyl phosphite was added thereto, wherein the mass ratio of hexa(4-formylphenoxy)cyclotriphosphazene, 5-amino-2-mercaptobenzimidazole and diethyl phosphite was 1:1.2:1.1, and an addition reaction was carried out. The reaction was carried out at 70°C for 6 hours. After completion, the reaction was distilled under reduced pressure and washed with ether to obtain intermediate 1. (3) Add 2-5 parts by weight of purified polyurethane particles to dimethylformamide solvent, stir and dissolve at 85°C for 6 hours, dry after completion, continue to add 2 parts by weight of methyl methacrylate isothiocyanate, introduce nitrogen for protection, then add 0.01 parts by weight of triethylamine, and place in an oil bath at 50°C for 8 hours. After the reaction, wash with acetonitrile and dry to obtain olefinic polyurethane; (4) Adding olefinic polyurethane to N,N-dimethylformamide solvent, stirring and dispersing, and then adding intermediate 1 and benzoin dimethyl ether photoinitiator, wherein the olefinic polyurethane, intermediate 1, and benzoin dimethyl ether photoinitiator are 1.3:1:0.02, irradiating with 365 nm ultraviolet light at 25° C. for 3 h, centrifuging, washing and drying to obtain sulfur-modified polyurethane; (5) 8 parts by weight of allyl glycidyl ether, tetrahydrofuran solvent and 0.4 parts by weight of chloroplatinic acid were added to the reactor, activated at 40°C for 32 minutes, and then 9 parts by weight of 1,1,3,3-tetramethyldisiloxane were added dropwise for 50 minutes. The reaction was continued at 50°C for 4 hours. After the reaction was completed, the mixture was cooled to room temperature, activated carbon adsorbent was added, ultrasonic vibration was performed for 30 minutes, the catalyst chloroplatinic acid was removed, and the mixture was filtered and rotary evaporated to obtain epoxy-modified siloxane; (6) adding epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst to N,N-dimethylformamide, wherein the mass ratio of epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst is 1.2:1:0.01, and performing a ring-opening reaction at 70° C. for 6 h. After the reaction, diluting the precipitate, filtering and washing to obtain modified silane; (7) 50 parts by weight of rare earth isoprene butadiene rubber, 2 parts by weight of calcium carbonate, 4 parts by weight of modified silane, 12 parts by weight of polyethylene, 4 parts by weight of sulfur-modified polyurethane, and 0.2 parts by weight of antioxidant 626 are added into a stirrer, mixed evenly, and melted at a melting temperature of 190° C. for a melting time of 20 min. The mixture is cooled to obtain flame-retardant and weather-resistant rare earth isoprene butadiene rubber. Example 2

[0019] (1) adding hexachlorocyclotrimer phosphazene and tetrahydrofuran solvent to a reactor, introducing nitrogen protection, stirring for 15 minutes, and continuing to add p-hydroxybenzaldehyde and anhydrous potassium carbonate, wherein the mass ratio of hexachlorocyclotrimer phosphazene, p-hydroxybenzaldehyde and anhydrous potassium carbonate is 1:3.4:0.03, heating to 80° C. and reflux reaction for 10 hours, filtering after completion, precipitating with petroleum ether, filtering by suction, washing with deionized water, and drying to obtain hexa(4-formylphenoxy)cyclotriphosphazene; (2) Hexa(4-formylphenoxy)cyclotriphosphazene and 5-amino-2-mercaptobenzimidazole were added to an ethanol solvent, and the mixture was stirred for condensation reaction at 80°C for 5 hours. Then, diethyl phosphite was added thereto, wherein the mass ratio of hexa(4-formylphenoxy)cyclotriphosphazene, 5-amino-2-mercaptobenzimidazole and diethyl phosphite was 1:1.4:1.5, and an addition reaction was carried out. The reaction was carried out at 90°C for 10 hours. After the reaction was completed, the mixture was distilled under reduced pressure and washed with ether to obtain intermediate 1. (3) Add 5 parts by weight of purified polyurethane particles to dimethylformamide solvent, stir and dissolve at 110°C for 10 hours, dry after completion, continue to add 3 parts by weight of methyl methacrylate isothiocyanate, introduce nitrogen for protection, then add 0.03 parts by weight of triethylamine, and place in an oil bath at 70°C for 10 hours. After the reaction, wash with acetonitrile and dry to obtain olefinic polyurethane; (4) Adding olefinic polyurethane to N,N-dimethylformamide solvent, stirring and dispersing, and then adding intermediate 1 and benzoin dimethyl ether photoinitiator, wherein the olefinic polyurethane, intermediate 1, and benzoin dimethyl ether photoinitiator are 1.6:1:0.04, irradiating with 365 nm ultraviolet light at 40° C. for 5 h, centrifuging, washing and drying to obtain sulfur-modified polyurethane; (5) 14 parts by weight of allyl glycidyl ether, tetrahydrofuran solvent and 0.6 parts by weight of chloroplatinic acid were added to the reactor, activated at 60°C for 50 minutes, and then 15 parts by weight of 1,1,3,3-tetramethyldisiloxane were added dropwise for 75 minutes. The reaction was continued at 65°C for 7 hours. After the reaction was completed, the mixture was cooled to room temperature, activated carbon adsorbent was added, ultrasonic vibration was performed for 45 minutes, the catalyst chloroplatinic acid was removed, and the mixture was filtered and rotary evaporated to obtain epoxy-modified siloxane; (6) adding epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst to N,N-dimethylformamide, wherein the mass ratio of epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst is 1.4:1:0.03, to carry out a ring-opening reaction at 95° C. for 10 h, diluting the precipitate after the reaction, filtering and washing to obtain modified silane; (7) Add 70 parts by weight of rare earth butadiene isoprene rubber, 3 parts by weight of calcium carbonate, 8 parts by weight of modified silane, 18 parts by weight of polyethylene, 7 parts by weight of sulfur-modified polyurethane, and 0.4 parts by weight of antioxidant 626 into a stirrer, mix well, and melt at a melting temperature of 200° C. for 40 min. Cool and obtain flame-retardant and weather-resistant rare earth butadiene isoprene rubber. Example 3

[0020] (1) adding hexachlorocyclotrimer phosphazene and tetrahydrofuran solvent to a reactor, introducing nitrogen protection, stirring for 13 minutes, continuing to add p-hydroxybenzaldehyde and anhydrous potassium carbonate, wherein the mass ratio of hexachlorocyclotrimer phosphazene, p-hydroxybenzaldehyde and anhydrous potassium carbonate is 1:2.8:0.02, heating to 75° C. and reflux reaction for 8 hours, filtering after completion, precipitating with petroleum ether, filtering by suction, washing with deionized water, and drying to obtain hexa(4-formylphenoxy)cyclotriphosphazene; (2) Hexa(4-formylphenoxy)cyclotriphosphazene and 5-amino-2-mercaptobenzimidazole were added to an ethanol solvent, stirred for condensation reaction, and reacted at 72°C for 4 hours. Then, diethyl phosphite was added thereto, wherein the mass ratio of hexa(4-formylphenoxy)cyclotriphosphazene, 5-amino-2-mercaptobenzimidazole and diethyl phosphite was 1:1.3:1.3, and an addition reaction was carried out. The reaction was carried out at 80°C for 8 hours. After completion, the reaction was distilled under reduced pressure and washed with ether to obtain intermediate 1. (3) Add 3.5 parts by weight of purified polyurethane particles to dimethylformamide solvent, stir and dissolve at 100°C for 8 hours, dry after completion, continue to add 2.5 parts by weight of methyl methacrylate isothiocyanate, introduce nitrogen for protection, then add 0.02 parts by weight of triethylamine, and place in an oil bath at 60°C for 9 hours. After the reaction, wash with acetonitrile and dry to obtain olefinic polyurethane; (4) Adding olefinic polyurethane to N,N-dimethylformamide solvent, stirring and dispersing, and then adding intermediate 1 and benzoin dimethyl ether photoinitiator, wherein the olefinic polyurethane, intermediate 1, and benzoin dimethyl ether photoinitiator are in a ratio of 1.5:1:0.03, irradiating with 365 nm ultraviolet light at 32° C. for 4 h, centrifuging, washing and drying to obtain sulfur-modified polyurethane; (5) 14 parts by weight of allyl glycidyl ether, tetrahydrofuran solvent and 0.5 parts by weight of chloroplatinic acid were added to the reactor, activated at 50°C for 45 minutes, and then 12 parts by weight of 1,1,3,3-tetramethyldisiloxane were added dropwise for 60 minutes. The reaction was continued at 62°C for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, activated carbon adsorbent was added, ultrasonic vibration was performed for 40 minutes, the catalyst chloroplatinic acid was removed, and the mixture was filtered and rotary evaporated to obtain epoxy-modified siloxane; (6) adding epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst to N,N-dimethylformamide, wherein the mass ratio of epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst is 1.3:1:0.02, to carry out a ring-opening reaction at 82° C. for 8 h, diluting the precipitate after the reaction, filtering and washing to obtain modified silane; (7) Add 60 parts by weight of rare earth isoprene butadiene rubber, 2 parts by weight of calcium carbonate, 6 parts by weight of modified silane, 14 parts by weight of polyethylene, 5 parts by weight of sulfur-modified polyurethane, and 0.3 parts by weight of antioxidant 626 into a stirrer, mix well, and melt at a melting temperature of 195° C. for 30 min. Cool and obtain flame-retardant and weather-resistant rare earth isoprene butadiene rubber.

[0021] Comparative Example 1 Add 60 parts by weight of rare earth butadiene isoprene rubber, 2 parts by weight of calcium carbonate, 14 parts by weight of polyethylene, 5 parts by weight of sulfur-modified polyurethane, and 0.3 parts by weight of antioxidant 626 into a stirrer, mix evenly, and melt at a melting temperature of 195° C. for 30 minutes. Cool and obtain flame-retardant and weather-resistant rare earth butadiene isoprene rubber.

[0022] Comparative Example 2 Add 60 parts by weight of rare earth butadiene isoprene rubber, 2 parts by weight of calcium carbonate, 6 parts by weight of modified silane, 14 parts by weight of polyethylene and 0.3 parts by weight of antioxidant 626 into a stirrer, mix evenly, and melt at a melting temperature of 195° C. for 30 minutes. Cool and obtain flame-retardant and weather-resistant rare earth butadiene isoprene rubber.

[0023] The oxygen index meter is used to test the limiting oxygen index of the flame retardant and weather resistant rare earth butadiene isoprene rubber; the horizontal and vertical combustion instrument is used to test the combustion grade of the flame retardant and weather resistant rare earth butadiene isoprene rubber.

[0024] Table 1: Flame retardancy tests.

[0025] project Limiting oxygen index (%) Combustion level Example 1 31 V-0 Example 2 33 V-0 Example 3 32 V-0 Comparative Example 1 21 V-1 Comparative Example 2 22 V-1 It can be seen from Table 1 that the flame retardant effect of Examples 1-3 is better than that of Comparative Examples 1-2, which indicates that the flame retardant and weather-resistant rare earth isoprene rubber prepared by the present invention has good flame retardant effect.

[0026] The tensile test was carried out in accordance with GB / T 1040.1-2018. The test results are shown in Table 2.

[0027] Table 2: Tensile strength test.

[0028] project Tensile strength (MPa) Example 1 55.4 Example 2 56.9 Example 3 56.2 Comparative Example 1 38.3 Comparative Example 2 39.5 It can be seen from Table 2 that the flame retardant and weather-resistant rare earth isoprene rubber of Examples 1-3 of the present invention have better tensile properties than those of Comparative Examples 1-2.

[0029] Weather resistance: After high and low temperature aging test (maintained at high temperature of 80°C for 8 hours, then reduced to low temperature of -40°C for 8 hours, and high and low temperature cycle) was carried out on the rare earth butadiene isoprene rubber provided in the embodiments of the present invention and the comparative examples for 500 hours, the appearance of the material was observed, and the toughness retention rate of the rare earth butadiene isoprene rubber was tested. The results are recorded in Table 3.

[0030] Table 3: Weathering test.

[0031] project Appearance Toughness retention rate (%) Example 1 No noticeable fading 88 Example 2 No noticeable fading 90 Example 3 No noticeable fading 89 Comparative Example 1 No noticeable fading 81 Comparative Example 2 No noticeable fading 83 It can be seen from Table 2 that the flame retardant and weather-resistant rare earth isoprene rubber of the present invention has good weather resistance.

[0032] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A flame retardant and weather-resistant rare earth isoprene rubber, characterized in that: The invention comprises the following components by weight: 50-70 parts by weight of rare earth isoprene rubber, 2-3 parts by weight of calcium carbonate, 4-8 parts by weight of modified silane, 12-18 parts by weight of polyethylene, 4-7 parts by weight of sulfur-modified polyurethane and 0.2-0.4 parts by weight of antioxidant 626.

2. The flame retardant and weather resistant rare earth isoprene rubber according to claim 1, characterized in that: The preparation method of the sulfur-modified polyurethane is as follows: (1) adding hexachlorocyclotriphosphazene and tetrahydrofuran solvent to a reactor, introducing nitrogen protection, stirring for 12-15 minutes, continuing to add p-hydroxybenzaldehyde and anhydrous potassium carbonate, heating to 65-80° C. and reflux reaction for 6-10 hours, filtering after completion, precipitating with petroleum ether, filtering by suction, washing with deionized water, and drying to obtain hexa(4-formylphenoxy)cyclotriphosphazene; (2) adding hexa(4-formylphenoxy)cyclotriphosphazene and 5-amino-2-mercaptobenzimidazole to an ethanol solvent, stirring for condensation reaction at 65-80°C for 3-5h, then adding diethyl phosphite for addition reaction at 70-90°C for 6-10h, and then distilling under reduced pressure after completion, washing with ether to obtain intermediate 1; (3) Add 2-5 parts by weight of purified polyurethane particles to dimethylformamide solvent, stir and dissolve at 85-110°C for 6-10 hours, dry after completion, continue to add 2-3 parts by weight of methyl methacrylate isothiocyanate, introduce nitrogen for protection, then add 0.01-0.03 parts by weight of triethylamine, and place in an oil bath at 50-70°C for 8-10 hours. After the reaction, wash with acetonitrile and dry to obtain olefinic polyurethane; (4) Add olefinated polyurethane to N,N-dimethylformamide solvent, stir and disperse, then add intermediate 1 and benzoin dimethyl ether photoinitiator, irradiate with 365 nm ultraviolet light at 25-40° C. for 3-5 h, centrifuge, wash and dry to obtain sulfur-modified polyurethane.

3. The flame retardant and weather resistant rare earth isoprene rubber according to claim 2, characterized in that: The mass ratio of hexachlorocyclotrimer phosphazene, p-hydroxybenzaldehyde and anhydrous potassium carbonate in (1) is 1:2.1-3.4:0.01-0.

03.

4. The flame retardant and weather resistant rare earth isoprene rubber according to claim 2, characterized in that: The mass ratio of hexa(4-formylphenoxy)cyclotriphosphazene, 5-amino-2-mercaptobenzimidazole and diethyl phosphite in (2) is 1:1.2-1.4:1.1-1.

5.

5. The flame retardant and weather resistant rare earth isoprene rubber according to claim 2, characterized in that: The olefinated polyurethane, the intermediate 1, and the benzoin dimethyl ether photoinitiator in the (4) are 1.3-1.6:1:0.02-0.

04.

6. The flame retardant and weather resistant rare earth isoprene rubber according to claim 1, characterized in that: The preparation method of the modified silane is: S1. 8-14 parts by weight of allyl glycidyl ether, tetrahydrofuran solvent and 0.4-0.6 parts by weight of chloroplatinic acid are added to a reactor, activated at 40-60°C for 32-50min, and then 9-15 parts by weight of 1,1,3,3-tetramethyldisiloxane are added dropwise for 50-75min, and the reaction is continued at 50-65°C for 4-7h. After the reaction is completed, the reaction is cooled to room temperature, an activated carbon adsorbent is added, ultrasonically shaken for 30-45min, the catalyst chloroplatinic acid is removed, filtered, and rotary evaporated to obtain epoxy-modified siloxane; S2. Add epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst to N,N-dimethylformamide for ring-opening reaction at 70-95°C for 6-10 hours. After the reaction, dilute the precipitate, filter and wash to obtain modified silane.

7. The flame retardant and weather resistant rare earth isoprene rubber according to claim 6, characterized in that: The mass ratio of epoxy-modified siloxane, intermediate 1 and tetrabutylammonium fluoride catalyst in S2 is 1.2-1.4:1:0.01-0.

03.

8. A method for preparing the flame retardant and weather resistant rare earth butyl isoprene rubber according to any one of claims 1 to 7, characterized in that: The preparation method of the flame retardant and weather resistant rare earth butadiene isoprene rubber is as follows: adding rare earth butadiene isoprene rubber, calcium carbonate, modified silane, polyethylene, sulfur-modified polyurethane and antioxidant 626 into a stirrer, mixing evenly, melting at a melting temperature of 190-200° C. and a melting time of 20-40 min, and cooling to obtain the flame retardant and weather resistant rare earth butadiene isoprene rubber.