阅读说明：本技术 一种橡胶 (Rubber ) 是由 王一然 周波 李鹏 于 2019-11-28 设计创作，主要内容包括：本发明公开了一种橡胶。该橡胶的阻燃性好,不易焦烧,方便施工操作,抗腐蚀性强。使用该橡胶的防护带具有更优的机械强度和耐候性,抗撕裂性能优异,在机械外力的作用下不易破损,使用寿命更长,防腐效果更优,大大减少了后期维护成本。(The invention discloses rubber. The rubber has good flame retardance, is not easy to scorch, is convenient for construction operation and has strong corrosion resistance. The protective belt using the rubber has the advantages of excellent mechanical strength and weather resistance, excellent tear resistance, difficulty in damage under the action of mechanical external force, longer service life, excellent corrosion resistance effect and greatly reduced later maintenance cost.)

1. A rubber raw material composition A is characterized by comprising the following components in parts by weight:

chlorosulfonated polyethylene: 30-50 parts;

calcined kaolin: 10-20 parts;

antimony trioxide: 1-10 parts;

titanium dioxide: 5-20 parts of a solvent;

aluminum hydroxide: 10-20 parts;

zinc borate: 1-5 parts;

tricresyl phosphate: 0-10 parts;

pentaerythritol: 0.5-2 parts;

dipentamethylenethiuram tetrasulfide: 0.5-2 parts;

n, N' -m-phenylenebismaleimide: 0.5-2 parts;

magnesium oxide: 1-4 parts;

processing aid: 1-2 parts;

pigment: 0.1 to 0.3 portion.

2. The rubber starting composition a as defined in claim 1, which is composed of the following components in parts by weight:

chlorosulfonated polyethylene: 40 parts of a mixture;

calcined kaolin: 10 parts of (A);

antimony trioxide: 5 parts of a mixture;

titanium dioxide: 6 parts of (1);

aluminum hydroxide: 20 parts of (1);

zinc borate: 5 parts of a mixture;

tricresyl phosphate: 4 parts of a mixture;

pentaerythritol: 2 parts of (1);

dipentamethylenethiuram tetrasulfide: 2 parts of (1);

n, N' -m-phenylenebismaleimide: 1 part;

magnesium oxide: 3 parts of a mixture;

polyethylene glycol 4000: 1.9 parts;

pigment: 0.1 part.

3. A rubber composition A which is obtained by compounding the rubber raw material composition A according to claim 1 or 2.

4. A rubber A semi-finished product characterized in that the raw material is the rubber raw material composition A as claimed in claim 1 or 2.

5. A rubber A produced from the rubber raw material composition A according to claim 1 or 2.

6. A rubber raw material composition B is characterized by comprising the following components in parts by weight:

chlorosulfonated polyethylene: 30-50 parts;

ethylene vinyl acetate copolymer: 10-30 parts;

calcined kaolin: 10-20 parts;

antimony trioxide: 1-10 parts;

aluminum hydroxide: 10-20 parts;

zinc borate: 1-5 parts;

tricresyl phosphate: 0-10 parts;

pentaerythritol: 0.5-2 parts;

dipentamethylenethiuram tetrasulfide: 0.5-2 parts;

magnesium oxide: 1-4 parts;

processing aid: 1-2 parts;

pigment: 0.1 to 0.5 portion.

7. The rubber feedstock composition B as defined in claim 6 which is comprised of the following components in parts by weight:

chlorosulfonated polyethylene: 30 parts of (1);

ethylene vinyl acetate copolymer: 10 parts of (A);

calcined kaolin: 18 parts of a mixture;

antimony trioxide: 5 parts of a mixture;

aluminum hydroxide: 20 parts of (1);

zinc borate: 5 parts of a mixture;

tricresyl phosphate: 4 parts of a mixture;

pentaerythritol: 1 part;

dipentamethylenethiuram tetrasulfide: 2 parts of (1);

magnesium oxide: 3 parts of a mixture;

polyethylene glycol 4000: 1.5 parts;

pigment: 0.5 part.

8. A rubber composition B characterized by being the rubber raw material composition B as claimed in claim 6 or 7.

9. A rubber B semi-finished product characterized by being the rubber raw material composition B as described in claim 6 or 7.

10. A rubber B produced from the rubber raw material composition B as described in claim 6 or 7.

Technical Field

The invention relates to a rubber.

Background

The bridge, oil gas pipeline etc. infrastructure influences the face to national economy and people's life, and it is metal material generally, in order to maintain above-mentioned infrastructure's long life, avoids leading to the fact premature of its service function to scrap because of corroding the reason, reduces economic loss, needs carry out necessary anticorrosive protection to it. Taking a suspension bridge main cable as an example, the suspension bridge main cable is taken as a life line of a suspension bridge, referring to the related description of a transportation industry standard JT/T694 2007 document of suspension bridge main cable system anticorrosion coating technical condition, the traditional bridge cable uses a vulcanized sealant as a surface anticorrosion material, the material has stable performance and long history of use, which is a commonly adopted scheme for the current bridge cable, however, the polysulfide sealant also has many defects in the long-term use process, the construction by means of manual blade coating requires huge constructors to construct simultaneously, the efficiency is low, the engineering quality is greatly influenced by the skills of the constructors, the thickness and the uniformity of coating cannot be accurately controlled, the tensile strength and the tear strength of the sealant are too low, cracking easily occurs, and a large amount of rainwater and wet air enter the main cable, resulting in corrosion failure. Based on the reasons, the main cable winding belt is developed in the industry to replace the main cable winding belt, the winding belt is prefabricated into a rubber belt roll with a certain thickness in a factory, the rubber belt roll is cut into rubber belt products with specific widths, and then a belt winding machine is used for spiral winding operation, so that the convenience of construction and the strength of an anticorrosive layer are greatly improved.

Disclosure of Invention

The invention aims to solve the technical problem of few types of the existing rubber, and therefore, the invention provides the rubber. The rubber has good flame retardance, is not easy to scorch, is convenient for construction operation and has strong corrosion resistance. The protective belt using the rubber has the advantages of excellent mechanical strength and weather resistance, excellent tear resistance, difficulty in damage under the action of mechanical external force, longer service life, excellent corrosion resistance effect and greatly reduced later maintenance cost.

The invention provides a rubber raw material composition A which is characterized by comprising the following components in parts by weight:

chlorosulfonated polyethylene: 30-50 parts;

calcined kaolin: 10-20 parts;

antimony trioxide: 1-10 parts;

titanium dioxide: 5-20 parts of a solvent;

aluminum hydroxide: 10-20 parts;

zinc borate: 1-5 parts;

tricresyl phosphate: 0-10 parts;

pentaerythritol: 0.5-2 parts;

dipentamethylenethiuram tetrasulfide: 0.5-2 parts;

n, N' -m-phenylenebismaleimide: 0.5-2 parts;

magnesium oxide: 1-4 parts;

processing aid: 1-2 parts;

pigment: 0.1 to 0.3 portion.

In the rubber raw material composition a, the "rubber raw material" may be a raw material for preparing: rubbers (e.g., vulcanized rubber, semi-vulcanized rubber), intermediates in the rubber preparation process (e.g., rubber compounds), and the like.

In a certain embodiment of the rubber raw material composition a, the chlorosulfonated polyethylene may be present in an amount of 40 parts.

In a certain embodiment of the rubber raw material composition a, the part of the chlorosulfonated polyethylene may be 40 type chlorosulfonated polyethylene.

In one embodiment of the rubber raw material composition a, the calcined kaolin may be 10 parts.

In a certain embodiment of the rubber raw material composition a, the antimony trioxide may be present in an amount of 5 parts.

In a certain scheme of the rubber raw material composition A, the titanium dioxide can be 6 parts.

In one embodiment of the rubber raw material composition a, the aluminum hydroxide may be present in an amount of 20 parts.

In one embodiment of the rubber material composition a, the zinc borate may be present in an amount of 5 parts.

In one embodiment of the rubber raw material composition a, the number of parts of tricresyl phosphate may be 4.

In one embodiment of the rubber raw material composition a, the pentaerythritol may be present in an amount of 2 parts.

In one embodiment of the rubber raw material composition a, the amount of the dipentamethylenethiuram tetrasulfide may be 2 parts.

In one embodiment of the rubber raw material composition a, the amount of the N, N' -m-phenylene bismaleimide may be 1 part.

In one embodiment of the rubber raw material composition a, the magnesium oxide may be present in an amount of 3 parts.

In one embodiment of the rubber raw material composition a, the processing aid may be 1.9 parts.

In one embodiment of the rubber raw material composition a, the processing aid can be an ingredient that is required to be added for normal rubber processing to improve rubber processing performance (such as non-stick roller), such as one or more of polyethylene glycol, PE wax, microcrystalline wax and oleamide, such as polyethylene glycol, and such as polyethylene glycol 4000.

In one embodiment of the rubber raw material composition a, the pigment may be present in an amount of 0.1 part.

In one embodiment of the rubber raw material composition a, the total amount of the rubber raw material composition a may be 100 parts.

In one embodiment of the rubber raw material composition a, the rubber raw material composition a may comprise the following components in parts by weight:

chlorosulfonated polyethylene: 40 parts of a mixture;

calcined kaolin: 10 parts of (A);

antimony trioxide: 5 parts of a mixture;

titanium dioxide: 6 parts of (1);

aluminum hydroxide: 20 parts of (1);

zinc borate: 5 parts of a mixture;

tricresyl phosphate: 4 parts of a mixture;

pentaerythritol: 2 parts of (1);

dipentamethylenethiuram tetrasulfide: 2 parts of (1);

n, N' -m-phenylenebismaleimide: 1 part;

magnesium oxide: 3 parts of a mixture;

polyethylene glycol 4000: 1.9 parts;

pigment: 0.1 part.

The invention also provides a rubber compound A, which is characterized in that the raw material of the rubber compound A is the rubber raw material composition A.

In one embodiment of the rubber composition a, the preparation method of the rubber composition a may be a preparation method conventional in the art, for example:

(1) plasticating chlorosulfonated polyethylene in the rubber raw material composition A to obtain plasticated rubber A;

(2) and (3) mixing the plasticated rubber A with the rest of the components in the rubber raw material composition A to obtain a mixed rubber A.

In a variant of said compound A, the temperature of said mastication may be that conventional in the art for mastications of this type, for example 100 ℃. + -. 5 ℃.

In a variant of the mix A, the mixing temperature may be that conventional for this type of mixing in the art, for example 100 ℃. + -. 5 ℃.

The rubber compound A can be a rubber compound A used for a bridge cable or an oil and gas transmission pipeline, and can also be a rubber compound A used for the bridge cable or the oil and gas transmission pipeline as a wrapping anti-corrosion protection material.

The invention also provides an application of the rubber compound A in a bridge cable or an oil and gas transmission pipeline.

In the application, the mixed rubber A can be used as a wrapping anticorrosion protective material.

The invention also provides a rubber A semi-finished product which is characterized in that the raw material is the rubber raw material composition A.

In one aspect of the rubber A semi-finished product, the "semi-finished product" refers to a semi-vulcanized product.

In one aspect of the semi-finished rubber a product, the semi-finished rubber a product may be prepared by a method conventional in the art, for example: and vulcanizing the mixed rubber A to obtain a semi-finished product of the rubber A.

In a particular version of the semi-finished rubber A, the vulcanization temperature may be that conventional in the art for such vulcanizates, for example 130 ℃ to 160 ℃.

In a particular version of the semi-finished rubber A, the vulcanization time may be that conventional in the art for such vulcanization, for example from 5min to 8 min.

In one version of the semi-finished rubber a product, the vulcanization mold clamping pressure may be a mold clamping pressure conventional to such vulcanization in the art, such as 10T.

The rubber A semi-finished product can be a rubber A semi-finished product used for a bridge cable or an oil and gas transmission pipeline, and can also be a rubber A semi-finished product used for the bridge cable or the oil and gas transmission pipeline as a winding anticorrosion protection material.

The invention also provides an application of the rubber A semi-finished product in bridge cables or oil and gas transmission pipelines. In the application, the semi-finished product of the rubber A can be used as a wrapping anticorrosion protective material.

The invention also provides a rubber A, which is characterized in that the raw material is the rubber raw material composition A.

In one embodiment of the rubber A, the "rubber" refers to a product which has undergone secondary vulcanization.

In one embodiment of the rubber a, the preparation method of the rubber a may be a preparation method conventional in the art, for example: and (3) carrying out secondary vulcanization on the semi-finished product of the rubber A to obtain the rubber A.

In one version of said rubber A, the temperature of said secondary vulcanization may be a temperature conventional for such vulcanization in the art, for example from 100 ℃ to 150 ℃ and again for example 130 ℃.

In one version of the rubber A, the time of the secondary vulcanization may be a time conventional in the art for such vulcanization, for example from 5min to 8min, and for example again 6 min.

The rubber A can be rubber A used for bridge cables or oil and gas transmission pipelines and can also be rubber A used for bridge cables or oil and gas transmission pipelines as a winding anticorrosion protection material.

The invention also provides application of the rubber A to bridge cables or oil and gas transmission pipelines. In the application, the rubber A can be used as a wrapping anticorrosion protective material.

The invention provides a rubber raw material composition B which is characterized by comprising the following components in parts by weight:

chlorosulfonated polyethylene: 30-50 parts;

ethylene vinyl acetate copolymer: 10-30 parts;

calcined kaolin: 10-20 parts;

antimony trioxide: 1-10 parts;

aluminum hydroxide: 10-20 parts;

zinc borate: 1-5 parts;

tricresyl phosphate: 0-10 parts;

pentaerythritol: 0.5-2 parts;

dipentamethylenethiuram tetrasulfide: 0.5-2 parts;

magnesium oxide: 1-4 parts;

processing aid: 1-2 parts;

pigment: 0.1 to 0.5 portion.

In the rubber raw material composition B, the "rubber raw material" may be a raw material for preparing: rubbers (e.g., vulcanized rubber, semi-vulcanized rubber), intermediates in the rubber preparation process (e.g., rubber compounds), and the like.

In a certain embodiment of the rubber raw material composition B, the chlorosulfonated polyethylene may be present in an amount of 30 parts.

In a certain embodiment of the rubber raw material composition B, the chlorosulfonated polyethylene may be 40 parts of chlorosulfonated polyethylene.

In one embodiment of the rubber material composition B, the ethylene-vinyl acetate copolymer may be present in an amount of 10 parts.

In one embodiment of the rubber raw material composition B, the calcined kaolin may be present in an amount of 18 parts.

In a certain embodiment of the rubber raw material composition B, the antimony trioxide may be present in an amount of 5 parts.

In one embodiment of the rubber raw material composition B, the aluminum hydroxide may be present in an amount of 20 parts.

In one embodiment of the rubber raw material composition B, the zinc borate may be present in an amount of 5 parts.

In one embodiment of the rubber raw material composition B, the number of parts of tricresyl phosphate may be 4.

In one embodiment of the rubber raw material composition B, the pentaerythritol may be present in an amount of 1 part.

In one embodiment of the rubber raw material composition B, the amount of the dipentamethylenethiuram tetrasulfide may be 2 parts.

In one embodiment of the rubber raw material composition B, the magnesium oxide may be present in an amount of 3 parts.

In one embodiment of the rubber raw material composition B, the processing aid may be present in an amount of 1.5 parts.

In one embodiment of the rubber raw material composition B, the processing aid can be an ingredient that is required to be added for normal rubber processing to improve rubber processing performance (such as non-stick roller), such as one or more of polyethylene glycol, PE wax, microcrystalline wax and oleamide, such as polyethylene glycol, and such as polyethylene glycol 4000.

In one embodiment of the rubber raw material composition B, the pigment may be present in an amount of 0.5 parts.

In one embodiment of the rubber raw material composition B, the total amount of the rubber raw material composition B may be 100 parts.

In one embodiment of the rubber raw material composition B, the rubber raw material composition B may comprise the following components in parts by weight:

chlorosulfonated polyethylene: 30 parts of (1);

ethylene vinyl acetate copolymer: 10 parts of (A);

calcined kaolin: 18 parts of a mixture;

antimony trioxide: 5 parts of a mixture;

aluminum hydroxide: 20 parts of (1);

zinc borate: 5 parts of a mixture;

tricresyl phosphate: 4 parts of a mixture;

pentaerythritol: 1 part;

dipentamethylenethiuram tetrasulfide: 2 parts of (1);

magnesium oxide: 3 parts of a mixture;

polyethylene glycol 4000: 1.5 parts;

pigment: 0.5 part.

The invention also provides a rubber compound B which is characterized in that the raw material of the rubber compound B is the rubber raw material composition B.

In one embodiment of the rubber composition B, the preparation method of the rubber composition B may be a preparation method conventional in the art, such as:

(1) plasticating chlorosulfonated polyethylene and ethylene-vinyl acetate copolymer in the rubber raw material composition B to obtain plasticated rubber B;

(2) and mixing the plasticated rubber B with the rest of the components in the rubber raw material composition B to obtain a mixed rubber B.

In a variant of the compound B, the temperature of the mastication may be that conventional for mastications of this type in the art, for example 100 ℃. + -. 5 ℃.

In a variant of the compound B, the mixing temperature may be that conventional for this type of mixing in the field, for example 100 ℃. + -. 5 ℃.

The rubber compound B can be a rubber compound B used for a bridge cable or an oil and gas transmission pipeline, and can also be a rubber compound B used for the bridge cable or the oil and gas transmission pipeline as a wrapping anti-corrosion protection material.

The invention also provides an application of the rubber compound B in a bridge cable or an oil and gas transmission pipeline. In the application, the rubber compound B can be used as a wrapping anticorrosion protective material.

The invention also provides a rubber B semi-finished product which is characterized in that the raw material is the rubber raw material composition B.

In one aspect of the rubber B semi-finished product, the "semi-finished product" refers to a semi-vulcanized product.

In one aspect of the semi-finished rubber B product, the semi-finished rubber B product may be prepared by a method conventional in the art, such as: and vulcanizing the rubber compound B to obtain a semi-finished product of the rubber B.

In a particular version of the semi-finished rubber B, the vulcanization temperature may be that conventional for such vulcanizates in the art, for example 130 ℃ to 160 ℃.

In a particular version of the semi-finished rubber B, the vulcanization time may be that conventional in the art for such vulcanization, for example from 5min to 8 min.

In one version of the semi-finished rubber B product, the vulcanization mold clamping pressure may be a mold clamping pressure conventional for such vulcanization in the art, such as 10T.

The rubber B semi-finished product can be a rubber B semi-finished product used for a bridge cable or an oil and gas transmission pipeline, and can also be a rubber B semi-finished product used for the bridge cable or the oil and gas transmission pipeline as a winding anticorrosion protection material.

The invention also provides an application of the rubber B semi-finished product in bridge cables or oil and gas transmission pipelines. In the application, the semi-finished product of the rubber B can be used as a wrapping anticorrosion protective material.

The invention also provides a rubber B, which is characterized in that the raw material is the rubber raw material composition B.

In one embodiment of the rubber B, the "rubber" refers to a product which has undergone secondary vulcanization.

In one embodiment of the rubber B, the preparation method of the rubber B may be a preparation method conventional in the art, for example: and (3) carrying out secondary vulcanization on the semi-finished product of the rubber B to obtain the rubber B.

In a version of said rubber B, the temperature of said secondary vulcanization may be a temperature conventional for such vulcanization in the art, for example from 100 ℃ to 150 ℃ and further for example 130 ℃.

In a variant of said rubber B, the time of said secondary vulcanization may be that conventional in the art for such vulcanization, for example from 5min to 8min, for example again 6 min.

The rubber B can be rubber B used for bridge cables or oil and gas transmission pipelines and can also be rubber B used for bridge cables or oil and gas transmission pipelines as a winding anticorrosion protection material.

The invention also provides application of the rubber B in bridge cables or oil and gas transmission pipelines. In the application, the rubber B can be used as a wrapping anticorrosion protective material.

The invention also provides a rubber belt C which is characterized in that the middle of the rubber belt C is provided with a mesh cloth, and the two sides of the mesh cloth are respectively provided with the mixed rubber A and the mixed rubber B.

In one embodiment of the rubber belt C, the material of the mesh fabric may be a material that is conventional in the rubber belts in the art, such as aramid, poly-p-phenylene terephthalamide, and kevlar. When the grid cloth is made of aramid fiber, the grid cloth can be subjected to acrylic acid glue dipping treatment. When the mesh cloth is made of aramid fiber, the specification of the mesh cloth can be 500D × 500D, 9 × 9 "," 850D × 850D, 9 × 9 "or" 1000D × 1000D, 9 × 9 ".

In one embodiment of the rubber belt C, the preparation method of the rubber belt C may be a preparation method conventional in the art, for example: and rolling the mixed rubber A and the mixed rubber B onto the mesh cloth.

In one embodiment of the rubber belt C, the calendering may be performed by a four-roll calender (e.g., an L-shaped four-roll calender).

In one embodiment of the rubber tape C, the calendering temperature can be a calendering temperature conventional in the art, such as 90 ℃ to 110 ℃, and such as 100 ℃.

In one embodiment of the rubber belt C, when a four-roll calender is used for calendering, the temperature parameters can be as follows: the first press roll temperature is 90-110 ℃, the second press roll temperature is 100-110 ℃, the third press roll temperature is 100-110 ℃, and the fourth press roll temperature is 90-100 ℃.

In a certain aspect of the rubber belt C, the width of the rubber belt C is 100mm to 300 mm.

The rubber belt C can be used for a bridge cable or an oil and gas conveying pipeline and can also be used as a rubber belt C for winding and wrapping an anti-corrosion protection material for the bridge cable or the oil and gas conveying pipeline.

The invention also provides an application of the rubber belt C in a bridge cable or an oil and gas transmission pipeline.

The invention also provides a rubber belt D, which is characterized by being prepared according to the following method: and (3) carrying out primary vulcanization on the rubber belt C to obtain a rubber belt D.

In one embodiment of the rubber belt D, the primary vulcanization may be performed by a drum vulcanizer.

In one version of the rubber belt D, the temperature of the primary vulcanization may be a temperature conventional to such vulcanization in the art, for example, 130 ℃ to 160 ℃.

In one version of the rubber belt D, the time for the first vulcanization may be a time conventional in the art for such vulcanization, for example, 5min to 8 min.

In one embodiment of the rubber belt D, the curing mold pressure may be a mold pressure conventional in the art for such curing, for example, 10T.

In one embodiment of the rubber belt D, the width of the rubber belt D is 100mm to 300 mm.

The rubber belt D can be used for a bridge cable or an oil and gas conveying pipeline and can also be used as a rubber belt D for winding and wrapping an anti-corrosion protection material for the bridge cable or the oil and gas conveying pipeline.

The invention also provides an application of the rubber belt D on a bridge cable or an oil and gas transmission pipeline.

The construction method of the rubber belt D is characterized by comprising the following steps of:

(1) wrapping the rubber belt D;

(2) the rubber tape D described above is heated.

In the construction method, the lamination proportion of the wrapping operation can be 30-50%.

In the construction method, the pressure applied to the rubber tape D during heating may be 0.01 to 0.1 MPa.

In the construction method, the heating temperature can be 100-150 ℃ or 130 ℃.

In the construction method, the heating time can be 5-8min or 6 min.

In the construction method, the welding and the secondary vulcanization can be simultaneously carried out in the step (2).

The invention also provides a rubber belt E, which is characterized by being prepared according to the following method: and (3) carrying out secondary vulcanization on the rubber belt D to obtain a rubber belt E.

In one version of the rubber belt E, the temperature of the secondary vulcanization may be a temperature conventional for such vulcanization in the art, such as 100 ℃ to 150 ℃, for example, 130 ℃.

In one version of the rubber belt E, the time of the secondary vulcanization may be a time conventional in the art for such vulcanization, for example 5 to 8min, and for example 6 min.

In one aspect of the rubber belt E, the width of the rubber belt E is 100mm to 300 mm.

The rubber belt E can be used for a bridge cable or an oil and gas transmission pipeline and can also be used as a rubber belt E for winding and wrapping an anti-corrosion protection material for the bridge cable or the oil and gas transmission pipeline.

The invention also provides an application of the rubber belt E on a bridge cable or an oil and gas transmission pipeline.

The above preferred conditions can be arbitrarily combined to obtain preferred embodiments of the present invention without departing from the common general knowledge in the art.

The reagents and starting materials used in the present invention are commercially available.

The positive progress effects of the invention are as follows: the rubber has good flame retardance, is not easy to coke, is convenient for construction operation and has strong corrosion resistance. The protective belt using the rubber has better mechanical strength and weather resistance, is not easy to damage under the action of mechanical external force, has longer service life and better corrosion resistance effect, and greatly reduces the later maintenance cost.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

In the following examples, the respective raw materials in the rubber formulation were regarded as being commercially available unless otherwise specified.