Rubber composition, composite material and preparation method thereof

Abstract

The invention belongs to the technical field of rubber materials, and particularly relates to a rubber composition, a composite material and a preparation method thereof. The rubber composite material comprises a rubber composition, a vulcanizing agent, an accelerant and an activating agent, the rubber composition comprises natural rubber and a filler, and the filler is calcium carbonate or a combination of carbon black and calcium carbonate; the calcium carbonate is modified biological source calcium carbonate; the modified biological source calcium carbonate comprises modified oyster shells or modified clam shells. The rubber composition containing the modified biological source calcium carbonate powder has excellent reinforcing performance, the prepared composite material has excellent vulcanization processing characteristics, mechanical characteristics and dynamic fatigue characteristics, meanwhile, the preparation process is simple and safe, large-scale industrialization is easy, and the preparation method is suitable for industrial production. The used biological source calcium carbonate is wide in source, low in cost, recyclable and environment-friendly, the problem of marine product shell waste pollution is solved, and the cost is effectively reduced.

Description

Technical Field

[0001] The invention belongs to the field of rubber materials, and in particular relates to a rubber composition, a composite material and a preparation method thereof. Background Art

[0002] Natural rubber (NR), as a renewable natural resource with superior comprehensive properties, has the characteristics of high elasticity, high strength, high elongation and wear resistance. It is widely used in aerospace, national defense, aircraft tires, medical elastomers and other fields, and occupies a very important position in economic construction. However, as a non-polar rubber, although NR does not react much in polar solvents, it is easy to react with hydrocarbon organic solvents, so its oil resistance and organic solvent resistance are poor; in addition, NR molecules contain unsaturated double bonds, so its resistance to thermal oxidation aging, ozone resistance and UV resistance are poor, all of which limit its application in some special occasions. For a long time, the modification of NR has been a hot research topic in this field.

[0003] The main component of shellfish is calcium carbonate. With the growth of seafood consumption groups in recent years, the scale of artificial shellfish culture in coastal areas has continued to expand, but a large number of shells are discarded as waste, causing serious environmental pollution. In particular, oyster shells (OS) are composed of organic macromolecules such as minerals, proteins and polysaccharides to form an orderly and regular multi-microlayer structure. Calcium carbonate accounts for more than 95% of the mass fraction of oyster shells. The natural structure of oyster shells contains a large number of 2-10μm micropores and has a certain adsorption capacity. In addition to the rich calcium content, it is also rich in more than 20 trace elements such as copper, iron, zinc, and manganese.

[0004] Existing modified rubbers have problems such as filler resource costs and environmental health, while the fillers of rubber products have problems such as high processing costs and insufficient environmental protection. At the same time, the shells of shellfish seafood full of calcium carbonate have the problem of waste pollution. Therefore, finding a green, environmentally friendly, low-cost, waste-to-treasure rubber filler, as well as researching high-performance modified rubber composite materials, are of great significance in today's society. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention uses shell waste as a filler for rubber to study its performance and perform modification, and proposes a modified rubber composition and a rubber composite material.

[0006] In a first aspect, the present invention provides a rubber composite material, comprising a rubber composition, a vulcanizer, an accelerator, and an activator; the mass ratio of the rubber composition, the vulcanizer, the accelerator, and the activator is 100-150:0.5-2:1-2.5:4-10; the rubber composition includes natural rubber and a filler, and the filler is calcium carbonate or a combination of carbon black and calcium carbonate.

[0007] Furthermore, the calcium carbonate is modified biogenic calcium carbonate; the modified biogenic calcium carbonate includes modified oyster shell or modified clam shell.

[0008] Furthermore, the mass ratio of the natural rubber to the filler is 10:1-4.

[0009] Furthermore, the modified biogenic calcium carbonate is obtained by acid washing, cleaning, water washing, drying, calcining and grinding.

[0010] Furthermore, the particle size of the modified biogenic calcium carbonate is 50-300 mesh; further, the particle size of the modified biogenic calcium carbonate is 100-200 mesh.

[0011] The pickling may be carried out by using dilute hydrochloric acid; the cleaning may be carried out by brushing to remove dirt or sand on the surface of the oyster shell or clam shell;

[0012] Wherein, the drying temperature is 80°C-100°C (for example, it can be 80°C, 85°C, 90°C, 95°C or 100°C), and the drying time is 6-12h (for example, it can be 6h, 7h, 8h, 9h, 10h, 11h or 12h).

[0013] Wherein, the calcination temperature is 500°C-850°C (for example, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C or 100°C), the calcination time is 5-10h (for example, 5h, 6h, 7h, 8h, 9h or 10h), and the calcination heating rate is 8-15°C / min (for example, 8°C / min, 9°C / min, 10°C / min, 11°C / min, 12°C / min, 13°C / min, 14°C / min or 15°C / min). The calcination can be carried out in a horse furnace, a rotary kiln or a calcining furnace.

[0014] Furthermore, the carbon black includes any one of N550, N660, N774, N220, N234, N326 or N330.

[0015] Furthermore, the vulcanizing agent is one or more of sulfur, benzyltriphenylphosphonium chloride, and peroxide vulcanizing agent.

[0016] Furthermore, the accelerator is one or more of 2-thiolbenzothiazole, N-tert-butyl-2-benzothiazolesulfenamide, diphenylguanidine, and zinc dimethyldithiocarbamate.

[0017] Furthermore, the activator is one or both of zinc oxide and stearic acid.

[0018] In a preferred embodiment, the rubber composite material comprises the following raw materials in parts by mass: natural rubber: 100-140 parts; modified oyster shell: 1-30 parts; carbon black N550: 0-30 parts; zinc oxide: 4-12 parts; stearic acid: 0-5 parts; N-tert-butyl-2-benzothiazolesulfonamide: 0.5-2 parts; diphenylguanidine: 0.5-2 parts; sulfur: 0.5-2 parts.

[0019] In a preferred embodiment, the rubber composite material comprises the following raw materials in parts by mass: natural rubber: 100 parts; modified oyster shell: 1-30 parts; carbon black N550: 0-30 parts; zinc oxide: 4-8 parts; stearic acid: 0-2 parts; N-tert-butyl-2-benzothiazolesulfonamide: 0.5-1 parts; diphenylguanidine: 0.5-1.5 parts; sulfur: 0.5-2 parts.

[0020] In a second aspect, the present invention provides a method for preparing a rubber composite material, comprising the following steps:

[0021] (1) firstly, the natural rubber and the filler are masticated for 1-5 minutes (for example, 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes) to obtain a rubber composition, then, an activator is added and masticated for 2-6 minutes (for example, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes), and then, the material is discharged to obtain a masticated mixture;

[0022] (2) Adding an accelerator and a vulcanizing agent to the plasticized mixture in sequence and kneading the mixture to obtain a rubber compound, and evenly standing the obtained rubber compound for 22-26 hours to obtain a rubber composite material.

[0023] The rubber mix is ​​evenly parked, usually by placing the rubber mix on a flat, clean, dry metal plate; the purpose of evenly parking the rubber mix is ​​to allow the vulcanizer, accelerator, and activator to further diffuse during the parking process, promote the bonding strength between the rubber compositions, improve the reinforcement effect, and relieve the fatigue and stress of the rubber mix.

[0024] Furthermore, the plasticizing equipment is preheated before plasticizing, and the preheating temperature is 40-60°C;

[0025] Furthermore, the plasticating equipment preferably uses an internal mixer with a rotation speed of 30 to 60 r / min, for example, 30 r / min, 35 r / min, 40 r / min, 45 r / min, 50 r / min, 55 r / min or 60 r / min;

[0026] Furthermore, the mixing equipment preferably uses an open mill, and the speed ratio of the two rollers of the open mill is 1:1.15-1:1.37, for example, 1:1.15, 1:1.17, 1:1.2, 1:1.25, 1:1.27, 1:1.3, 1:1.35 or 1:1.37; the speed range of the open mill is 12 to 22 r / min.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The calcium carbonate source of the rubber composition filler of the present invention is selected from biogenic calcium carbonate with wide sources, low cost, recyclability and green environmental protection, such as oyster shells, clam shells, etc., and seafood shells with high calcium carbonate content are selected and obtained through modification to obtain seafood shell powder, which solves the problem of waste pollution of seafood shells and achieves the effect of reducing the cost of rubber fillers; the embodiment of the present invention shows the preparation of rubber compositions and rubber composite materials by using modified biogenic calcium carbonate and carbon black in different proportions as fillers, and it is found that the rubber composition using modified biogenic calcium carbonate has excellent reinforcement performance and the use characteristics of rubber compositions with different filler proportions are studied. At the same time, the preparation process is simple and safe, and easy to be industrialized on a large scale. The prepared rubber composition and composite material have excellent vulcanization processing characteristics, mechanical properties and dynamic fatigue properties as verified by experiments. The low-loss and fatigue-resistant rubber composite material can be widely used in many fields such as transportation, national defense aviation, etc.

[0029] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the specific embodiments listed in the description. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present invention clearer, the implementation scheme of the present application will be described in detail below in conjunction with specific examples. The technical terms and scientific terms used in the present invention have the meanings generally understood by those of ordinary skill in the art to which the present invention belongs, without other definitions. Without departing from the concept of the present invention, those skilled in the art may make various improvements and changes to the specific implementation methods of the present invention specification, which all belong to the protection scope of the present invention. The raw materials used in the present invention are all commercially available unless otherwise specified.

[0031] In a specific embodiment, the biogenic calcium carbonate is pickled, cleaned, washed, dried, calcined, and ground to obtain modified biogenic calcium carbonate. The pickling is to select dilute hydrochloric acid for pickling; the cleaning can be done by brushing to remove dirt or mud on the surface of the oyster shell; the drying temperature is 80°C-100°C, and the drying time is 6-12h. The calcination temperature is 500°C-850°C, the calcination time is 5-10h, the calcination heating rate is 8-15°C / min, and the calcination can be done using a horse furnace, a rotary kiln, or a calcining furnace. The particle size of the modified biogenic calcium carbonate is 50-300 mesh; the biogenic calcium carbonate is exemplarily oyster shells or clam shells.

[0032] Comparative Example 1

[0033] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 30 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0034] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0035] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0036] Example 1

[0037] The oyster shells are pickled, cleaned, washed, dried, calcined, and ground to obtain modified oyster shell powder. Specifically, dilute hydrochloric acid pickling is selected, and the cleaning is performed by brushing to remove dirt or sand on the surface of the oyster shells, then washed with water, and dried at 85°C for 10 hours, and then calcined at 600°C for 8 hours in a Ma Fuel Furnace at a heating rate of 10°C / min, and then ground in a crucible after cooling to obtain modified oyster shell powder, wherein the particle size of the modified oyster shell powder is 100-200 meshes.

[0038] A rubber composite material comprises 100 parts by weight of natural rubber, 5 parts by weight of modified oyster shell powder, 25 parts by weight of carbon black N550, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 0.5 parts by weight of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts by weight of accelerator diphenylguanidine, and 1.5 parts by weight of sulfur.

[0039] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0040] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0041] Example 2

[0042] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 10 parts of modified oyster shell powder, 20 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0043] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0044] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0045] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0046] Example 3

[0047] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 15 parts of modified oyster shell powder, 15 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0048] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0049] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0050] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0051] Example 4

[0052] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 20 parts of modified oyster shell powder, 10 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0053] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0054] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0055] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0056] Example 5

[0057] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 25 parts of modified oyster shell powder, 5 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0058] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0059] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0060] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0061] Example 6

[0062] A rubber composite material comprises 100 parts by weight of natural rubber, 30 parts by weight of modified oyster shell powder, 0 parts by weight of carbon black N550, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 0.5 parts by weight of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts by weight of accelerator diphenylguanidine, and 1.5 parts by weight of sulfur.

[0063] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0064] The internal mixer was preheated to 40°C, the speeds of the two rollers of the mixer were 15 r / min and 19 r / min, and the speed was set to 40 r / min. The natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and mixed for 3 min, and finally the filler was added and mixed for 4 min before discharging.

[0065] On an open mill, an accelerator and a vulcanizing agent are sequentially added to a solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0066] Example 7

[0067] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 30 parts of modified oyster shell powder, 0 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1 part of sulfur.

[0068] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0069] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0070] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0071] Example 8

[0072] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 30 parts of modified oyster shell powder, 0 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 2 parts of sulfur.

[0073] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0074] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0075] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0076] Example 9

[0077] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 10 parts of modified oyster shell powder, 0 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0078] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0079] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0080] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0081] Example 10

[0082] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 20 parts of modified oyster shell powder, 0 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0083] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0084] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0085] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0086] Embodiment 11

[0087] A rubber composite material comprises the following components by weight: 100 parts of natural rubber, 40 parts of modified oyster shell powder, 0 parts of carbon black N550, 5 parts of zinc oxide, 1 part of stearic acid, 0.5 parts of accelerator N-tert-butyl-2-benzothiazole sulfenamide, 0.7 parts of accelerator diphenylguanidine, and 1.5 parts of sulfur.

[0088] Wherein, the modified oyster shell powder is obtained according to the method described in Example 1.

[0089] The internal mixer was preheated to 40°C, the speed was set to 40 r / min, the natural rubber was added to the internal mixer and plasticized for 2 min, then the activator was added and plasticized for 3 min, and finally the filler was added and plasticized for 4 min before discharging.

[0090] On an open mixing mill, the speeds of the two rollers of the mixing mill are 15 r / min and 19 r / min, and the accelerator and the vulcanizer are sequentially added to the solid rubber composition and mixed to obtain a mixed rubber, which is evenly rolled down and left to stand for 24 hours to obtain a rubber composite material.

[0091] Example 12

[0092] The difference from Example 11 is that the modified oyster shell powder is replaced by modified clam shell powder, and the modified clam shell powder is obtained by pickling, cleaning, washing, drying, calcining, and grinding the clam shells. Specifically, dilute hydrochloric acid pickling is selected, and the cleaning is performed by brushing to remove dirt or mud on the surface of the clam shells, followed by washing with water and drying at 85°C for 10h, and then calcining at 600°C for 8h at a heating rate of 10°C / min using a horse furnace, and then grinding in a crucible after cooling to obtain the modified clam shell powder, and the particle size of the modified clam shell powder is 100-200 mesh.

[0093] The above-mentioned embodiments and comparative examples were subjected to vulcanization processing characteristic test, mechanical characteristic test and dynamic fatigue characteristic test, and Table 1, Table 2 and Table 3 were obtained respectively.

[0094] Table 1 Vulcanization processing characteristics data

[0095] <![CDATA[Minimum torque M L / dNm]]> <![CDATA[Maximum torque M H / dNm]]> <![CDATA[T 10 / min]]> <![CDATA[T 90 / min]]> Comparative Example 1 0.65 12.57 3.12 10.72 Example 1 0.68 12.74 2.89 9.57 Example 2 0.66 12.89 3.35 10.81 Example 3 0.72 12.67 3.08 10.59 Example 4 0.77 13.51 3.77 10.91 Example 5 0.74 13.23 3.57 10.41 Example 6 0.75 13.98 3.19 10.56 Example 7 0.78 13.36 4.86 12.81 Example 8 0.82 14.54 2.81 9.08 Example 9 0.48 12.99 3.27 9.56 Example 10 0.58 13.45 3.56 10.52 Embodiment 11 0.92 14.02 4.05 11.07 Example 12 0.88 13.76 3.84 10.63

[0096] Table 1 shows the vulcanization processing characteristics of each embodiment. The experimental equipment used is RPA2000 vulcanization processing analyzer, and the experimental conditions are 140°C×40min. From the data of Comparative Example 1 and Embodiments 1 to 6 or the data of Embodiments 6 and Embodiments 9 to 11 in Table 1, it can be seen that the minimum torque M of the rubber composite material prepared by the present invention is L As the proportion of modified oyster shell powder added to the total filler increases, it shows an increasing trend. H -M LAs the amount of sulfur increases, it increases, which indicates an increase in the degree of crosslinking. In addition, it can be seen that the compound rubber of the modified oyster shell powder system has a higher minimum torque M L With the change of the ratio of modified oyster shell powder and carbon black N550, the scorch time T 10 , positive vulcanization time T 90 The change is not big. Further control of the amount of sulfur added. Examples 6 to 8 show that as the amount of sulfur increases, the scorch time T 10 , positive vulcanization time T 90 It can be seen from Examples 11 and 12 that the rubber composite material prepared by using the modified oyster shell powder in the present invention is slightly better than the rubber composite material prepared by using the modified clam shell powder in terms of vulcanization processing performance.

[0097] Table 2 Mechanical properties data

[0098]

[0099]

[0100] Table 2 shows the mechanical properties of each embodiment. The experimental equipment used is an electronic tensile machine, and the experimental conditions are carried out in accordance with GB / T528-2009. First, it can be seen from Examples 1 to 6 that as the percentage of modified oyster shell powder in the total filler increases, the rubber composite material has a hardness, tensile strength, elongation at break and tear strength comparable to those of Comparative Example 1 (pure carbon black N550 filler). It can be seen from Examples 6, 9 to 11 that as the amount of modified oyster shell powder added increases, the hardness, tensile strength and tear strength of the rubber composite material increase significantly, and the elongation at break first increases and then decreases. It can be seen from Examples 11 and 12 that the rubber composite material prepared using modified oyster shell powder in the present invention is slightly better than the rubber composite material prepared using modified clam shell powder in terms of mechanical properties. In summary, the excellent reinforcement properties of modified oyster shell powder are demonstrated.

[0101] Table 3 Dynamic fatigue characteristics data

[0102]

[0103]

[0104] Table 3 shows the dynamic fatigue properties of each embodiment. The experimental equipment used is a flexure tester. The experimental conditions are performed in accordance with the standard GB / T 1687.3-2016), where the starting temperature of the compression heat test is 55°C, the prestress is 1MPa, and the stroke is 4.45mm. It can be seen that with the addition of modified oyster shell powder, the rubber composite material still has the same compression heat, loss factor and compression fatigue times as the carbon black system, and the dynamic fatigue performance is relatively excellent. For example, the performance characterization of rubber materials formulated based on the application requirements of aviation rubber elastic elements, within a certain range, the smaller the compression heat, the better, and the smaller the loss factor, the better the elasticity of the rubber material; the compression fatigue times are the end point when the compression stiffness decreases by 30% during the dynamic compression fatigue process. The slower the decrease, the greater the compression fatigue times, and the better the fatigue performance. It can be seen from Examples 11 and 12 that the rubber composite material prepared using modified oyster shell powder in the present invention is slightly better than the rubber composite material prepared using modified clam shell powder in terms of dynamic fatigue properties.

[0105] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A rubber composite material, characterized in that: The invention comprises a rubber composition, a vulcanizing agent, an accelerator and an activator; the mass ratio of the rubber composition, the vulcanizing agent, the accelerator and the activator is 100-150:0.5-2:1-2.5:4-10; the rubber composition comprises natural rubber and a filler, and the filler is calcium carbonate or a combination of carbon black and calcium carbonate.

2. The rubber composite material according to claim 1, characterized in that: The calcium carbonate is modified biogenic calcium carbonate; the modified biogenic calcium carbonate is modified oyster shell or modified clam shell.

3. The rubber composite material according to claim 1, characterized in that: The mass ratio of the natural rubber to the filler is 10:1-4.

4. The rubber composite material according to claim 2, characterized in that: The modified biogenic calcium carbonate is obtained by acid washing, cleaning, water washing, drying, calcining and grinding.

5. The rubber composite material according to claim 4, characterized in that: The particle size of the modified biogenic calcium carbonate is 50-300 meshes.

6. The rubber composite material according to claim 1, characterized in that: The carbon black is any one of N550, N660, N774, N220, N234, N326 or N330.

7. The rubber composite material according to claim 1, characterized in that: The vulcanizing agent is one or more of sulfur, benzyltriphenylphosphonium chloride and peroxide vulcanizing agent.

8. The rubber composite material according to claim 1, characterized in that: The accelerator is one or more of 2-mercaptobenzothiazole, N-tert-butyl-2-benzothiazolesulfenamide, diphenylguanidine, and zinc dimethyldithiocarbamate.

9. The rubber composite material according to claim 1, characterized in that: The activator comprises one or both of zinc oxide and stearic acid.

10. A method for preparing a rubber composite material, for preparing the rubber composite material according to any one of claims 1 to 9, characterized in that: The following steps are involved: First, the natural rubber and filler are masticated for 1-5 minutes to obtain a rubber composition, then an activator is added and masticated for 2-6 minutes, and then the material is discharged to obtain a masticated mixture; The accelerator and the vulcanizing agent are sequentially added into the plasticized mixture and mixed to obtain a rubber compound, and the obtained rubber compound is evenly placed to obtain a rubber composite material.

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