CN110643072A

CN110643072A - Supported sulfur, preparation method and application thereof, and rubber composition

Info

Publication number: CN110643072A
Application number: CN201910773595.7A
Authority: CN
Inventors: 温世鹏; 郑龙; 刘力
Original assignee: Beijing University of Chemical Technology
Current assignee: Beijing University of Chemical Technology
Priority date: 2019-08-21
Filing date: 2019-08-21
Publication date: 2020-01-03

Abstract

The invention relates to a preparation method and application of supported sulfur and a rubber composition. The supported sulfur comprises nano filler and sulfur supported on the nano filler, wherein the content of the sulfur is 0.5-80 wt%. The invention applies the load-type sulfur to natural rubber and various synthetic rubbers to prepare the rubber composite material. The sulfur can be rapidly melted and infiltrated on the surface of the nano filler in high-temperature vulcanization, so that the agglomeration of the nano filler can be effectively prevented, the uniform dispersion of the nano filler in the rubber is realized, and the dynamic and static performances and the like of the rubber composite material can be greatly improved. In addition, the invention has the advantages of simple equipment, simple operation, good controllability, contribution to industrial production and the like.

Description

Supported sulfur, preparation method and application thereof, and rubber composition

Technical Field

The invention relates to the technical field of rubber, in particular to supported sulfur, a preparation method and application thereof, and a rubber composition.

Background

Rubber is a strategic material related to the countryside of China and is also one of indispensable industrial raw materials. Because the strength of the pure rubber is lower, the pure rubber has use value after being reinforced by the nano filler when being used for preparing the rubber composite material. However, the nano-filler is easy to agglomerate in the rubber matrix due to the large specific surface area. The dispersion of the nano filler in the rubber matrix plays a key role in the performance of the rubber composite material. To improve the dispersion of the nanofiller, different processes may be used depending on the situation. At present, the main processing methods for improving the dispersibility of the nano-filler comprise a melting compounding method, an emulsion compounding method, a solution compounding method and the like. Through the control of the process, the nano filler can be well dispersed in the early processing process. However, for optimum performance of the rubber composite, a high temperature vulcanization stage must be passed. The vulcanization process is a thermodynamically unstable process. In the process, the fillers are inevitably agglomerated to different degrees, thereby reducing the comprehensive performance of the rubber composite material. Therefore, how to improve the dispersibility of the filler in the rubber matrix is a difficult problem to be solved urgently in the rubber industry.

Disclosure of Invention

In order to solve the problems in the prior art, the invention adopts a simple and efficient method to load sulfur on the surface of the nano filler to obtain the loaded sulfur, and the loaded sulfur and other rubber additives are filled in rubber.

One of the purposes of the invention is to provide supported sulfur, which comprises a nano filler and sulfur supported on the nano filler, wherein the content of the sulfur is 0.5-80 wt%, preferably 3-60 wt%, and more preferably 5-30 wt%.

The nano filler can be a filler commonly used in the rubber field, and is preferably one or more of carbon black, white carbon black, carbon nanotubes, cellulose, chitosan, lignin, starch, short fibers, aramid fibers, graphene oxide, reduced graphene oxide, hydrotalcite, halloysite, kaolin, montmorillonite, clay, vermiculite, attapulgite, boehmite, alumina, zinc oxide, titanium dioxide, boron nitride, molybdenum disulfide and Mxene, and more preferably one or more of carbon black, white carbon black, carbon nanotubes, graphene, clay and hydrotalcite.

The second purpose of the invention is to provide a preparation method of the supported sulfur, wherein the supported sulfur is prepared from components including nano-filler, a sulfur precursor and acid, and the mass ratio of the nano-filler to the sulfur precursor is (0.1-20): 1, preferably (0.3-15): 1, more preferably (0.3 to 8): 1.

the sulfur precursor is preferably one or more of sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, calcium thiosulfate, thioacetamide, sodium sulfide and potassium sulfide.

The acid is preferably one or more of hydrochloric acid, sulfuric acid, nitric acid, hydrobromic acid, hydroiodic acid, perchloric acid and acetic acid.

Preferably, the preparation method comprises the following steps:

(1) dispersing the nano filler in a solvent to obtain a dispersion liquid, wherein the concentration of the nano filler is 0.01-30 wt%;

(2) adding the sulfur precursor into the nano filler dispersion liquid obtained in the step (1), and stirring for 1-1000 min until the sulfur precursor and the nano filler are uniformly mixed;

(3) and (3) dropwise adding an acid solution into the mixed solution obtained in the step (2), and stirring and reacting for 10-600 min at the temperature of 0-100 ℃ to obtain the supported sulfur.

In the step (1), the concentration of the nano filler is more preferably 0.1-15 wt%;

in the step (1), the adopted solvent is deionized water or an organic solvent. The organic solvent is preferably at least one of tetrahydrofuran, N-dimethylformamide, absolute ethanol, and the like.

In the step (1), the dispersion method of the nano filler can adopt a method which is common in the prior art.

In the step (2), the stirring time is preferably 30-180 min.

In the step (3), the concentration of the acid solution is preferably 1 to 20 wt%, and more preferably 3 to 10 wt%.

In step (3), the acid is used in excess.

In the step (3), the reaction is preferably carried out for 60-400 min under stirring at 20-80 ℃.

Further, the step (3) comprises the steps of filtering, washing and drying the obtained supported sulfur reaction product.

The filtration, washing and drying are not particularly limited, and a method generally used in the art is employed.

The invention also aims to provide application of the load-type sulfur in rubber.

The fourth purpose of the invention is to provide a rubber composition, which comprises rubber and the supported sulfur. The rubber can be various types of rubber, and preferably is at least one of natural rubber, styrene butadiene rubber, nitrile rubber, epoxy natural rubber and chloroprene rubber.

The supported sulfur is preferably 1 to 60 parts by weight, more preferably 2 to 55 parts by weight, based on 100 parts by weight of the rubber.

Various auxiliary agents commonly used in the field, such as zinc oxide, stearic acid, an anti-aging agent, an accelerator and the like, can be added into the rubber composition according to the processing requirement, and the dosage of the auxiliary agents is conventional dosage or is adjusted according to the requirement of the actual situation.

The antioxidant, the accelerator and the like are selected from the antioxidants, the accelerators and the like which are generally used in the field.

In the preparation process of the rubber composition, the processes of mixing, open milling, vulcanization and the like of the raw material components can adopt the common rubber processing process in the prior art. The equipment used is also the equipment in rubber processing in the prior art, such as kneaders, internal mixers, roll mills, vulcanizing machines and the like.

The invention adopts a simple method, loads sulfur on the surface of the nano filler, and applies the sulfur to rubber to prepare the high-performance rubber composite material.

In the rubber composition system, the sulfur on the surface of the nano filler not only plays a role of a vulcanizing agent, but also plays a role of a dispersing agent. In the high-temperature vulcanization process, the sulfur is rapidly melted (the melting point of the sulfur is 118 ℃) and infiltrates the surface of the nano filler, so that the aggregation of the nano filler can be effectively prevented, and the uniform dispersion of the filler is realized. Therefore, the dynamic and static performances of the rubber composite material can be greatly improved.

Drawings

FIG. 1 is a transmission electron micrograph of the CB/NR vulcanizate of comparative example 1.

FIG. 2 is a transmission electron micrograph of S-CB/NR vulcanizate of example 1.

FIG. 3 is a stress-strain curve of S-CB/NR of example 1 and CB/NR vulcanizate of comparative example 1.

FIG. 4 is a DMA curve for the S-CB/NR of example 1 and the CB/NR vulcanizate of comparative example 1.

FIG. 5 is a transmission electron micrograph of clay-supported sulfur.

Detailed Description

The present invention will be further described with reference to the following specific embodiments. The rubbers, nanofillers, auxiliaries and acid solutions used in the following are all commercially available.

The test criteria for each property in the following examples and comparative examples are as follows: the tensile strength is tested according to GB/T528-.

The elemental analysis was measured using an elemental analyzer (model vairo EL CUBE, Germany).

Example 1

Adding 50g of carbon black into deionized water, and stirring at a high speed for 4h to obtain a carbon black water dispersion liquid with the mass concentration of 5%. Adding 13.3g potassium thiosulfate (Chinese medicine reagent) into the carbon black water dispersion liquid, and stirring for 30min until the mixture is uniformly mixed. Then, 108.5g of a 5% hydrochloric acid solution was added dropwise thereto, and the mixture was stirred at room temperature for 2 hours. After the reaction is finished, the reactant is filtered, washed and dried to obtain the carbon black supported sulfur (S-CB). The sulfur content in the carbon black-supported sulfur was determined to be 3.99% by elemental analysis.

The S-CB prepared as described above is applied to Natural Rubber (NR) to prepare an S-CB/NR composite. The formula comprises the following components in parts by weight: NR 100; zinc oxide 4; stearic acid 1; anti-aging agent 4010NA 2; accelerator CZ 1.8; S-CB 52. According to the formula, placing NR into a double-roller open mill with phi 160mm multiplied by 320mm for plastication, sequentially adding an active agent, an anti-aging agent, an accelerator and S-CB, cutting rubber, rolling for 10 times, thin and passing through for 5 times, and then discharging. And carrying out mould pressing vulcanization (143 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 1

And respectively and independently adding the carbon black and the sulfur into the NR by adopting a direct blending method to prepare the CB/NR composite material. The formula comprises the following components in parts by weight: NR 100; zinc oxide 4; stearic acid 1; anti-aging agent 4010NA 2; accelerator CZ 1.8; CB 50; and 2, sulfur. According to the formula, NR is put into a double-roller open mill with phi 160mm multiplied by 320mm for plastication, and an active agent, an anti-aging agent, carbon black, an accelerator and sulfur are sequentially added. Tapping and rolling for 10 times, and taking out after 5 times. And carrying out mould pressing vulcanization (143 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

FIGS. 1 and 2 are transmission electron micrographs of the two vulcanizates. As can be seen from FIG. 1, significant agglomeration of the carbon black in the CB/NR vulcanizate occurred; no significant agglomerates were seen in the S-CB/NR vulcanizate (FIG. 2), indicating that a uniform dispersion of the carbon black was achieved. FIG. 3 is a stress-strain curve of the two vulcanizates, which can be seenThus, S-CB/NR vulcanizates have higher tensile strength and modulus at the same carbon black loading fraction. FIG. 4 is a DMA curve for the two vulcanizates and it can be seen that the S-CB/NR vulcanizate has a lower loss factor value at 60 deg.C. Further, the Akron abrasion value of the vulcanized rubber CB/NR was 0.192cm³The Akron abrasion value of the S-CB/NR vulcanized rubber is 0.165cm and is 1.61km³And/1.61 km. The above experimental results show that the carbon black loaded sulfur can improve the dispersion of the carbon black in the rubber matrix, thereby improving the comprehensive performance of the rubber composite material.

Example 2

Adding 10g of clay into water, stirring for 12h, and then carrying out ultrasonic treatment in an ultrasonic device for 60min (the ultrasonic power is 400w) to obtain a clay water dispersion liquid with the mass fraction of 5%. To the clay aqueous dispersion was added 8.1g of sodium thiosulfate (a national reagent), and stirred for 60min until uniformly mixed. 130g of a 5% nitric acid solution was added dropwise thereto, and the mixture was stirred at room temperature for 2 hours. After the reaction is finished, the reactant is filtered, washed and dried to obtain the Clay-supported sulfur (S-Clay). FIG. 5 is a transmission electron micrograph of clay-supported sulfur. The sulfur content in the S-Clay was determined to be 13.04% by elemental analysis.

The S-Clay prepared by the method is applied to emulsion polymerized styrene butadiene rubber (ESBR) to prepare the S-Clay/ESBR composite material. The formula comprises the following components in parts by weight: ESBR 100; 3.5 parts of zinc oxide; stearic acid 1; an anti-aging agent RD 3; accelerator NS 1.8; S-Clay 11.5. According to the formula, ESBR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, an accelerator and S-Clay are sequentially added, rubber tapping is performed for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 2

The Clay/ESBR composite material is prepared by respectively and independently adding Clay and sulfur into ESBR by adopting a direct blending method. The formula comprises the following components in parts by weight: ESBR 100; 3.5 parts of zinc oxide; stearic acid 1; an anti-aging agent RD 3; accelerator NS 1.8; clay 10; 1.5 of sulfur. According to the formula, ESBR is put into a double-roll mill with phi 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, clay, an accelerator and sulfur are sequentially added, rubber is cut, the mixture is rolled for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 2 and comparative example 2 are given in table 1 below:

TABLE 1 comparison of vulcanizate Properties of example 2 and comparative example 2

Test specimen	S-Clay/ESBR	Clay/ESBR
			Tensile Strength (MPa)	8.4	5.3
Tear Strength (kN/m)	25	17
			300% definite elongation (MPa)	2.8	1.8
Elongation at Break (%)	732	569
			Hardness (Shao A)	59	58
Permeability coefficient of nitrogen (x 10)^-17m²s^-1pa^-1)	4.4	5.3

Example 3

Adding 5g of graphene and 0.5g of dispersant octylphenol polyoxyethylene ether into deionized water, stirring for 30min, and then carrying out ultrasonic treatment in an ultrasonic device for 30min (the ultrasonic power is 500w) to obtain a graphene water dispersion liquid with the mass dispersion of 0.3%. 4.01g of sodium sulfide (Alfa) was added to the graphene aqueous dispersion, and stirred for 50min until mixed uniformly. 114.05g of a hydrochloric acid solution having a mass fraction of 8% was then added dropwise thereto, and the mixture was stirred at room temperature for 6.5 hours. And after the reaction is finished, filtering, washing and drying the reactant to obtain the graphene supported sulfur (S-GE). The sulphur content in the S-GE was 21.42% as determined by elemental analysis.

The S-GE prepared by the method is applied to Nitrile Butadiene Rubber (NBR) to prepare the S-GE/NBR composite material. The formula comprises the following components in parts by weight: NBR 100; 5 parts of zinc oxide; stearic acid 3; an anti-aging agent RD 3; accelerator DM 1.8; S-GE 7. According to the formula, the NBR is put into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, an accelerant and S-GE are sequentially added, rubber tapping and rolling are carried out for 10 times, and the mixture is thin and passed through for 5 times and then is taken out. And carrying out mould pressing vulcanization (155 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 3

And respectively and independently adding the graphene and the sulfur into the NBR by adopting a direct blending method to prepare the GE/NBR composite material. The formula comprises the following components in parts by weight: NBR 100; 5 parts of zinc oxide; stearic acid 3; an anti-aging agent RD 3; accelerator DM 1.8; 5, graphene; 1.5 of sulfur. According to the formula, the NBR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, graphene, an accelerant and sulfur are sequentially added, rubber tapping is performed for rolling for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (155 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 3 and comparative example 3 are as follows:

TABLE 2 comparison of vulcanizate Properties of example 3 and comparative example 3

Test specimen	S-GE/NBR	GE/NBR
			Tensile Strength (MPa)	16.8	12.5
Tear Strength (kN/m)	43.2	31.4
			300% definite elongation (MPa)	7.3	5.1
Elongation at Break (%)	582	436
			Conductivity (S/m)	1.5×10^-3	7.8×10^-5

Example 4

Mixing 40g of whiteAdding carbon black into deionized water, and stirring at high speed for 360min to obtain 20% white carbon black water dispersion. 8.93g ammonium thiosulfate (Aladdin) is added into the white carbon black water dispersion, and the mixture is stirred for 80min until the mixture is uniformly mixed. Then, 220.4g of a 5% sulfuric acid solution was added dropwise thereto, and the mixture was stirred at 60 ℃ for 5 hours. After the reaction is finished, the reactant is filtered, washed and dried to obtain silicon dioxide supported sulfur (S-SiO)₂). Determination of S-SiO by elemental analysis₂The content of sulfur in the product is 4.31%.

The S-SiO prepared above is used₂Applied to Butadiene Rubber (BR) to prepare S-SiO₂a/BR composite material. The formula comprises the following components in parts by weight: BR 100; 5 parts of zinc oxide; 2 parts of stearic acid; 1.5 of an anti-aging agent RD; accelerator NS 1.5; an accelerator TT 1; S-SiO₂41.8. According to the formula, BR is put into a double-roller mill with phi 160mm multiplied by 320mm for plastication, and an active agent, an anti-aging agent, a promoter and S-SiO are sequentially added₂Tapping and rolling for 10 times, and taking out after 5 times. And carrying out mould pressing vulcanization (151 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 4

Adopting a direct blending method to prepare SiO by separately adding white carbon black and sulfur into BR₂a/BR composite material. The formula comprises the following components in parts by weight: BR 100; 5 parts of zinc oxide; 2 parts of stearic acid; 1.5 of an anti-aging agent RD; accelerator NS 1.5; an accelerator TT 1; 40 parts of white carbon black; 1.8 of sulfur. According to the formula, BR is put into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, white carbon black, an accelerator and sulfur are sequentially added, rubber is cut, the mixture is rolled for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (151 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 4 and comparative example 4 are as follows in table 3:

table 3 comparison of vulcanizate properties for example 4 and comparative example 4

Test specimen	S-SiO₂/BR	SiO₂/BR
			Tensile Strength (MPa)	13.7	9.3
Tear Strength (kN/m)	31.2	22.3
			300% definite elongation (MPa)	7.4	5.2
Elongation at Break (%)	412	377
			Hardness (Shao A)	56	57
Akron abrasion (cm)³/1.61km)	0.071	0.104
			Dynamic temperature rise (. degree. C.)	21.6	27.5

Example 5

30g of alumina is added into deionized water, and the mixture is stirred for 180min to obtain an alumina water dispersion liquid with mass dispersion of 6%. 12.89g of calcium thiosulfate (alatin) was added to the aqueous alumina dispersion and stirred for 150min until mixed well. 380.4g of a 3% hydrochloric acid solution was added dropwise thereto, and the mixture was stirred at room temperature for 6 hours. After the reaction is finished, the reactant is filtered, washed and dried to obtain the aluminum oxide supported sulfur (S-AlO)₃). Determination of S-AlO by elemental analysis₃The content of sulfur in the product is 7.69%.

The S-AlO prepared by the method₃Applied to solution polymerized styrene butadiene rubber (SSBR) to prepare S-AlO₃a/SSBR composite material. The formula comprises the following components in parts by weight: an SSBR 100; 3.5 parts of zinc oxide; 2 parts of stearic acid; an anti-aging agent RD 2; an anti-aging agent 40201; 1 part of paraffin wax; accelerator NS 1.5; S-AlO₃32.5. According to the formula, SSBR is put into a double-roller mill with phi 160mm multiplied by 320mm for plastication, and an active agent, an anti-aging agent, paraffin, a promoter and S-AlO are sequentially added₃Tapping and rolling for 10 times, and taking out after 5 times. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 5

Adopting a direct blending method to prepare AlO by separately adding alumina and sulfur into SSBR₃a/SSBR composite material. The formula comprises the following components in parts by weight: an SSBR 100; 3.5 parts of zinc oxide; 2 parts of stearic acid; an anti-aging agent RD 2; an anti-aging agent 40201; 1 part of paraffin wax; accelerator NS 1.5; 30 parts of aluminum oxide; 2.5 of sulfur. According to the formula, SSBR is put into a double-roller mill with phi 160mm multiplied by 320mm for plastication, an activating agent, an anti-aging agent, paraffin, alumina, an accelerator and sulfur are sequentially added, rubber tapping is performed for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 5 and comparative example 5 are given in table 4 below:

TABLE 4 comparison of vulcanizate Properties of example 5 and comparative example 5

Example 6

15g of cellulose and 2g of potassium hydroxide are added into deionized water and stirred for 180min to obtain a cellulose water dispersion with mass dispersion of 6%. To the aqueous cellulose dispersion, 6.86g of potassium sulfide (Alfa) was added, and the mixture was stirred for 200min until the mixture was mixed uniformly. Then, 200.8g of a 10% nitric acid solution was added dropwise thereto, and the mixture was stirred at room temperature for 6 hours. After the reaction is finished, the reactant is filtered, washed and dried to obtain cellulose-supported sulfur (S-CN). The sulphur content in the S-CN was found to be 10.18% by elemental analysis.

The S-CN prepared by the method is applied to Epoxy Natural Rubber (ENR) to prepare the S-CN/ENR composite material. The formula comprises the following components in parts by weight: ENR 100; zinc oxide 4; 2 parts of stearic acid; anti-aging agent RD 2.5; 0.2 of accelerator DM; promoter CZ 1.5; S-CN 16.7. According to the formula, ENR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, an accelerator and S-CN are sequentially added, rubber is cut, the mixture is rolled for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (143 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 6

And respectively and independently adding the cellulose and the sulfur into the ENR by adopting a direct blending method to prepare the CN/ENR composite material. The formula comprises the following components in parts by weight: ENR 100; zinc oxide 4; 2 parts of stearic acid; anti-aging agent RD 2.5; 0.2 of accelerator DM; promoter CZ 1.5; 15 of cellulose; 1.7 of sulfur. According to the formula, ENR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an activating agent, an anti-aging agent, cellulose, an accelerant and sulfur are sequentially added, rubber tapping is performed for rolling for 10 times, and the mixture is thin and passed through for 5 times and then is taken out. And carrying out mould pressing vulcanization (143 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 6 and comparative example 6 are given in table 5 below:

TABLE 5 comparison of vulcanizate Properties of example 6 and comparative example 6

Test specimen	S-CN/ENR	CN/ENR
			Tensile Strength (MPa)	22.6	17.3
Tear Strength (kN/m)	40.8	31.5
			300% definite elongation (MPa)	5.4	3.9
Elongation at Break (%)	740	736

Example 7

1.5g of carbon nano tube (surface carboxylation) is added into deionized water and stirred for 40min to obtain the carbon nano tube water dispersion liquid with the mass dispersion of 0.2 percent. 4.69g of sodium sulfide (Alfa) was added to the aqueous dispersion of carbon nanotubes and stirred for 60min until the mixture was homogeneous. 134g of a 5% sulfuric acid solution was then added dropwise thereto, and the mixture was stirred at 70 ℃ for 2.5 hours. After the reaction, the reaction product was filtered, washed, and dried to obtain carbon nanotube-supported sulfur (S-CNT). The sulphur content in the S-CNT was found to be 56.25% by elemental analysis.

The S-CNT prepared by the method is applied to Emulsion Styrene Butadiene Rubber (ESBR) to prepare an S-CNT/ESBR composite material. The formula comprises the following components in parts by weight: ESBR 100; 3.5 parts of zinc oxide; stearic acid 1; an anti-aging agent RD 2; an anti-aging agent 40201; an accelerator TMTD 1; an accelerator M1; S-CNT 3.2. According to the formula, ESBR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, an accelerator, S-CNT and rubber tapping are sequentially added, the mixture is rolled for 10 times, and the mixture is rolled for 5 times and then is taken out. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

Comparative example 7

And respectively and independently adding the carbon nano tube and the sulfur into the ESBR by adopting a direct blending method to prepare the CNT/ESBR composite material. The formula comprises the following components in parts by weight: ESBR 100; 3.5 parts of zinc oxide; stearic acid 1; an anti-aging agent RD 2; an anti-aging agent 40201; an accelerator TMTD 1; an accelerator M1; CNT 1.5; 1.8 of sulfur. According to the formula, ESBR is placed into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, an active agent, an anti-aging agent, a carbon nano tube, an accelerator and sulfur are sequentially added, rubber is cut, the mixture is rolled for 10 times, and the mixture is thin and passed through for 5 times and then is taken out. And carrying out mould pressing vulcanization (150 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 7 and comparative example 7 are as follows:

TABLE 6 comparison of vulcanizate Properties of example 7 and comparative example 7

Test specimen	S-CNT/ESBR	CNT/ESBR
			Tensile Strength (MPa)	4.8	3.9
300% definite elongation (MPa)	2.4	2.2
			Elongation at Break (%)	510	596
Fatigue life (times)	105986	94610

Example 8

Adding 50g of starch into deionized water, and stirring at a high speed for 300min to obtain a starch water dispersion liquid with the mass dispersion of 1%. To the aqueous starch dispersion, 2.68g of potassium sulfide (Alfa) was stirred for 100min until mixed uniformly. Then, 101.2g of a 10% hydrochloric acid solution was added dropwise thereto, and the mixture was stirred at 50 ℃ for 6 hours. And after the reaction is finished, filtering, washing and drying the reactant to obtain the starch stone supported sulfur (S-DF). The sulphur content in S-DF was found to be 1.38% by elemental analysis.

The S-DF prepared above is applied to Chloroprene Rubber (CR) to prepare an S-DF/CR composite material. The formula comprises the following components in parts by weight: CR 100; zinc oxide 3; MgO 2; stearic acid 1; anti-aging agent 4010NA 2; promoter NA 221; S-DF 50.7. According to the formula, placing CR into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, sequentially adding an active agent, an anti-aging agent, an accelerator and S-DF, cutting rubber, rolling for 10 times, thin and passing through for 5 times, and then taking out the sheet. And carrying out mould pressing vulcanization (158 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

And (3) respectively and independently adding starch and sulfur into CR by adopting a direct blending method to prepare the DF/CR composite material. The formula comprises the following components in parts by weight: CR 100; zinc oxide 3; MgO 2; stearic acid 1; anti-aging agent 4010NA 2; promoter NA 221; 50 parts of starch; 0.7 of sulfur. According to the formula, placing CR into a double-roller open mill with the diameter of 160mm multiplied by 320mm for plastication, sequentially adding an active agent, an anti-aging agent, starch, an accelerator and sulfur, cutting rubber, rolling for 10 times, thin and passing through for 5 times, and then taking out the sheet. And carrying out mould pressing vulcanization (158 ℃) by a 25t electric heating flat plate vulcanizing machine to obtain vulcanized rubber, and testing various performances of the vulcanized rubber according to corresponding national standards.

The vulcanizate test properties in example 8 and comparative example 8 are given in table 7 below:

TABLE 7 comparison of vulcanizate Properties of example 8 and comparative example 8

Test specimen	S-DF/CR	DF/CR
			Tensile Strength (MPa)	8.2	6.1
Water swelling Rate (%)	675	433

The above embodiments have described the specific implementation of the present invention in detail, but the present invention is not limited to the embodiments, and those skilled in the art can make various modifications and improvements to the technical solution of the present invention without departing from the design of the present invention, and the modifications and improvements are within the scope of the present invention defined by the claims.

Claims

1. The supported sulfur is characterized by comprising a nano filler and sulfur loaded on the nano filler, wherein the sulfur content is 0.5-80 wt%.

2. The supported sulfur of claim 1, wherein:

the content of the sulfur is 3-60 wt%, preferably 5-30 wt%.

3. The supported sulfur of claim 1, wherein:

the nano filler is one or more of carbon black, white carbon black, carbon nano tubes, cellulose, chitosan, lignin, starch, short fibers, aramid fibers, graphene oxide, reduced graphene oxide, hydrotalcite, halloysite, kaolin, montmorillonite, clay, vermiculite, attapulgite, boehmite, aluminum oxide, zinc oxide, titanium dioxide, boron nitride, molybdenum disulfide and Mxene.

4. A process for the preparation of supported sulphur according to any of claims 1 to 3, wherein:

the supported sulfur is prepared from components including nano-filler, a sulfur precursor and acid, wherein the mass ratio of the nano-filler to the sulfur precursor is (0.1-20): 1, preferably (0.3-15): 1, more preferably (0.3 to 8): 1.

5. the method for preparing supported sulfur according to claim 4, wherein:

the sulfur precursor is one or more of sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, calcium thiosulfate, thioacetamide, sodium sulfide and potassium sulfide; and/or the presence of a gas in the gas,

the acid is one or more of hydrochloric acid, sulfuric acid, nitric acid, hydrobromic acid, hydroiodic acid, perchloric acid and acetic acid.

6. The process for the preparation of supported sulphur according to claim 4 or 5, characterized in that it comprises the following steps:

(1) dispersing the nano filler in a solvent to obtain a dispersion liquid, wherein the concentration of the nano filler is 0.01-30 wt%, and preferably 0.1-15 wt%;

(2) adding the sulfur precursor into the nano filler dispersion liquid obtained in the step (1), and stirring for 1-1000 min, preferably 30-180 min;

(3) and (3) dropwise adding an acid solution into the mixed solution obtained in the step (2), and stirring and reacting at 0-100 ℃ for 10-600 min to obtain the supported sulfur, wherein the stirring and reacting at 20-80 ℃ is preferably carried out for 60-400 min.

7. The method for preparing supported sulfur according to claim 6, wherein:

in the step (3), the concentration of the acid solution is 1-20 wt%, preferably 3-10 wt%.

8. Use of the supported sulphur of any of claims 1 to 3 in rubber.

9. A rubber composition comprising a rubber and the supported sulfur according to any one of claims 1 to 3, wherein the rubber is preferably at least one of natural rubber, styrene-butadiene rubber, nitrile rubber, epoxy natural rubber and chloroprene rubber.

10. The rubber composition according to claim 9, characterized in that:

based on 100 parts by weight of the rubber, 1-60 parts of the supported sulfur is used.