KR101792329B1 - Rubber composition for sealing material composing silica, carbonblack, and method thereof - Google Patents

Abstract

The present invention provides a sealant rubber composition comprising a raw material rubber, silica and a particulate carbon compound. Specifically, the sealing material rubber composition contains 10 to 50 parts by weight of the particulate carbon compound and 2 to 30 parts by weight of silica with respect to 100 parts by weight of the raw material rubber. The present invention also provides a method for producing a sealant rubber composition by mixing raw rubber, silica, and a particulate carbon compound.

Description

TECHNICAL FIELD [0001] The present invention relates to a sealant rubber composition comprising silica and carbon black, and a method for producing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a sealant rubber composition comprising silica and carbon black, and a method of producing the same.

Generally, gases, fluids such as gas, air, steam, water, etc. are transported through piping. The valves are used for various purposes such as controlling the flow rate of the fluid piping, opening and closing the flow path, and maintaining the piping safety. These pipes or valves are typically used in the manufacture of various rubber-elastic materials, such as rubber chemicals and additives, in order to bond them together. The most important element in ball valves is sealing. A round O-ring is installed to block the leakage of working fluid such as gas or liquid along the stall of machine structure or contact area with small relative momentum. The O-ring is an easy-to-install and very small installation space because it has an axisymmetric shape in which the cutting surface always maintains a circular shape.

On the other hand, fluorine-based rubbers are widely used in various fields such as automobile industry, semiconductor industry, and chemical industry as sealing materials such as O-rings, stem seals and shaft seals in that they exhibit excellent chemical resistance, solvent resistance and heat resistance . Examples thereof are used as hoses and sealing materials used for engines and peripheral devices in the automobile industry, AT devices, fuel systems, and peripheral devices. When the crosslinkable fluorine-containing rubber composition obtained by kneading the fluorine-based rubber and the fluorine-based resin at a temperature not lower than the melting point of the fluorine-based resin at a temperature not lower than the melting point of the fluorine-based resin is molded and heated at a temperature not lower than the melting point of the fluorine-based resin, (Patent Application No. 2011-7008083) discloses that a fluorine-containing rubber molded article of increased low friction is obtained.

The fluorine rubber-based sealing material is usually produced by mixing a fluororubber, a crosslinking agent, a filler, and various additives with a roll or the like, followed by compression molding. Further, in order to increase the performance thereafter, it is common to carry out secondary crosslinking. However, in the crosslinked system with the peroxide / TAIC system, the initial process causes a thermally uniform cleavage of the peroxide molecule to produce two oxy radicals. Primary pyrolysis forms a number of radicals, such radicals that form radical intermediates by extracting bromine (Br) atoms from FKM, and are added to TAIC to become more stable radical intermediates. Thus, the intermediate radicals extract bromine from the fluororubber polymer to produce polymer radicals. The crosslinking is stabilized by a capping reaction by a coagent. The molecular chains of the fluorine rubber having a high molecular weight are cleaved by mechanical stress or shearing force applied at the time of processing, and as a result, low molecular weight water and uncrosslinked polymers are produced. The sealing material containing the fluorine rubber containing the low molecular weight water or the uncrosslinked polymer is hardly adhered to and adhered to the material to be adhered and adversely affects the operation of the device in the dynamic part.

Further, the hardness of the rubber compound can be influenced by the filler, and carbon black and so-called white filler, mainly silica, calcium carbonate and kaolin, are well known among the fillers (Patent Registration No. 0341317). Further, in order to develop a product for high-hardness O-ring, expert knowledge on the formulation of fluorine rubber is required. The company tried to develop the localization of fluorine rubber O-ring for high hardness by a large company but it failed due to lack of technical skill and the research data is also confidential and has not been made progress anymore. General fluororubber contains a cross-linking agent in the raw material rubber and is molded by simply adding the additive. On the other hand, since pure fluorine rubber (gum) needs to be directly injected into the crosslinking agent, designing an optimum crosslinking system requires considerable difficulty.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. Therefore, the present invention is to study the physical properties of raw materials and raw materials and rubber materials of O-ring products used in natural gas pipelines, to design physical formulations of high hardness suitable for FKM rubber, We intend to realize high value added rubber products by developing high hardness fluorine rubber O-ring for piping ball valve.

However, the technical problem to be solved by the present invention is not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

Hereinafter, various embodiments described herein will be described with reference to the drawings. In the following description, for purposes of complete understanding of the present invention, various specific details are set forth, such as specific forms, compositions and processes, and the like. However, certain embodiments may be practiced without one or more of these specific details, or with other known methods and forms. In other instances, well-known processes and techniques of manufacture are not described in any detail, in order not to unnecessarily obscure the present invention. Reference throughout this specification to "one embodiment" or "embodiment" means that a particular feature, form, composition, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Accordingly, the appearances of the phrase " in one embodiment "or" an embodiment "in various places throughout this specification are not necessarily indicative of the same embodiment of the present invention. In addition, a particular feature, form, composition, or characteristic may be combined in any suitable manner in one or more embodiments.

Unless defined otherwise in the specification, all scientific and technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

When carbon black is used to increase the hardness of the rubber composition, the viscosity of the rubber mixture is also greatly increased, adversely affecting the mixing process. In such cases, a plasticizer such as mineral oil, so-called process oil or plasticizer, is used to reduce the viscosity. However, the mineral oil remaining in the already prepared rubber compound reduces the hardness and stiffness. When the liquid phase is used as the plasticizer of the fluorine rubber, the DBS powder is used because the slip property of the plasticizer does not mix with the fluorine rubber due to the slip property during the rolling operation and the DBS (Di-butyl sebacate) . However, since the plasticizer volatilizes during the secondary crosslinking (230 占 폚 占 24 hrs) of the product, the hardness increases and the physical properties deteriorate, and the liquid fluorine rubber is expensive. Accordingly, an object of the present invention is to provide a rubber composition which is excellent in low temperature properties and physical properties even in high hardness, low temperature fluorine rubber (PL 855), and fluorine rubber for high hardness which does not lower the hardness and rigidity of cross- Sealing material. In particular, it is desirable to apply the sealing material for ball valves for high-pressure natural gas, which enables the production of mechanical rubber products having high stiffness and glass transition temperature (Tg).

Fluorine-containing elastomers (also known as FKMs) are used in these seals in a variety of environments that require resistance to strong chemicals. Perfluoroelastomers are particularly commonly used to exhibit special chemical resistance, solvent resistance and thermal resistance, and thus these elastomers are widely used to seal materials when placed in the most unfavorable environment. Perfluoroelastomer materials are well known for their chemical resistance and plasma resistance and, when used in compositions with common fillers or reinforcing systems for acceptable compression, set resistance levels and mechanical properties do. Usually, they are intended to be used to form a molded part that can withstand deformation to be used as an elastomeric sealing material in applications, where the seal or gasket is to be placed in highly corrosive chemicals and / or extreme operating conditions It is applicable for many purposes, including.

Unless defined otherwise in the specification, all scientific and technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

In order to achieve the above object, the present invention provides a sealing material rubber composition comprising a raw material rubber, silica, and a particulate carbon compound in a sealing material rubber composition. In one embodiment of the present invention, the raw rubber is fluoro rubber, the particulate carbon compound is any one of graphite powder, carbon nanotube, and carbon black, the particulate carbon compound is carbon black, The particulate carbon compound is contained in an amount of 10 to 50 parts by weight based on 100 parts by weight of the raw rubber, and the sealing material is 2 to 30 parts by weight based on 100 parts by weight of the raw rubber. The sealing material rubber composition preferably contains 20 to 40 parts by weight of the particulate carbon compound per 100 parts by weight of the raw rubber, and the sealing material rubber composition preferably contains 5 to 15 parts by weight of silica relative to 100 parts by weight of the raw rubber , And the raw rubber has a hardness of 70 to 90, and preferably, the raw rubber has a hardness of 90.

In order to achieve the above object, the present invention provides a method for producing a sealant rubber composition by mixing raw rubber, silica, and a particulate carbon compound. In one embodiment of the present invention, the processing aid, the crosslinking agent, the co-crosslinking agent and the zinc oxide are further mixed, the raw rubber is fluorine rubber, and the fine particle carbon compound is any one of graphite powder, carbon nanotube, , And the particulate carbon compound is carbon black. Also, the sealing material rubber composition contains 10 to 50 parts by weight of the particulate carbon compound with respect to 100 parts by weight of the raw rubber, and the sealing material rubber composition has 2 to 30 parts by weight of silica relative to 100 parts by weight of the raw rubber. The sealing material rubber composition preferably contains 20 to 40 parts by weight of the particulate carbon compound per 100 parts by weight of the raw rubber, and the sealing material rubber composition preferably contains 5 to 15 parts by weight of silica relative to 100 parts by weight of the raw rubber , The raw rubber has a hardness of 70 to 90, and the raw rubber has a hardness of 90.

In order to achieve the above object, the present invention provides a molded article comprising the above-mentioned sealing material rubber composition. In one embodiment of the present invention, the shaped body can be used in a high-pressure gas supply facility.

In order to achieve the above object, the present invention provides a method for manufacturing a rubber molded article by filling a mold with the sealant rubber composition as described above, followed by heat molding. In one embodiment of the present invention, the rubber molded body is subjected to secondary crosslinking under a high temperature.

The sealing rubber composition according to the present invention has the effect of decreasing the hardness change rate and the volume expansion rate as the hardness of the raw material rubber is higher and being stable. Further, the sealing rubber composition according to the present invention is excellent in compression set ratio and low temperature characteristics. Further, the sealing rubber composition according to the present invention is excellent in general physical properties, heat resistance and fuel oil resistance.

1 is a graph showing changes in hardness with time after pressing for 14 days.
2 is a graph showing the volume expansion rate with time after pressurization for 14 days.
3 is a graph showing general physical properties.
4 is a graph showing heat resistance.
5 is a graph showing the fuel oil resistance.
6 is a graph showing oil resistance.

Hereinafter, the present invention will be described in more detail with reference to Examples. It will be apparent to those skilled in the art that these embodiments are only for describing the present invention in more detail and that the scope of the present invention is not limited by these embodiments in accordance with the gist of the present invention .

The sealing rubber composition of the present invention contains fluorine rubber (also referred to as FKM) as a rubber component.

<Fluorine rubber>

As the raw material rubber, conventionally known fluorine rubber can be widely used, and examples thereof include fluorinated vinylidene-hexafluoropropylene copolymer, fluorinated vinylidene-hexafluoropropylene-tetrafluoroethylene copolymer (e.g., Vinylidene fluoride-perfluoroalkyl vinyl ether-tetrafluoroethylene copolymer (e.g., &quot; Daiell LT302 &quot; manufactured by Daikin Industries, Ltd.) , Ethylene-perfluoroalkyl vinyl ether-tetrafluoroethylene copolymer, and tetrafluoroethylene-propylene copolymer. Preferably, poly (vinylidene fluoride) / hexafluoro-propylene / tetrafluoroethylene terpolymers can be used.

Examples of these FKMs include "DYEEL series" manufactured by Daikin Industries, "Viton series" manufactured by DuPont Dow Elastomers, "Tecnoflon series" manufactured by Solvay, "Sumitomo 3M" Dyneon fluorine rubber "available from Asahi Glass Co., Ltd., and" Fluon AFLAS series "available from Asahi Glass Co., Ltd. can be used. Preferably, FKM is "Technoflon PL-855" manufactured by Solvay.

Further, FKM containing a cure site monomer (CSM) having the following structure (1) can be used. A peroxide crosslinking system was used for the crosslinking of the fluororubber. By using a peroxide cross-linking agent as the cross-linking agent, the compression set ratio can be improved.

Regardless of the amount of carbon added, PL-855 has a low physical property change, excellent oil resistance, and excellent heat resistance. Also, PL-855 has excellent compression set ratio irrespective of the amount of carbon added, and low-temperature brittleness is higher than -20 ° C from 100 phr or more. At the same hardness level, PL-855 is more excellent at low temperature brittleness than the others.

&Lt; Carbon black (C) >

Specific examples of the filler (or reinforcing agent) include carbon black ("medium thermal N-990" (trade name, available from Can Cak)), silica, clay, silicate, alumina, aluminum hydroxide, calcium carbonate, Barium, titanium oxide, and the like.

In general, the smaller the particle diameter, the better the mechanical properties and hardness as the structure develops. The workability is better as the particle diameter is larger. However, fluororubber mainly uses MT carbon having excellent heat stability, and occasionally HAF or SRF carbon can also be used. The properties according to the types of carbon black are shown in Table 1 below.

Comparing the carbon blacks in Table 1, HAF and SRF did not significantly increase the hardness of the fluororubber after compounding, even though the particle size was small. However, the elongation percentage of HAF and SRF was larger than that of MT carbon.

This is because the use of a large amount of carbon in the progress of high hardness compounding can not form a bound rubber in the fluorine rubber even if a certain amount of carbon is used. Therefore, due to the excessive amount of carbon, the hardness can be improved but the physical properties are lowered. Particularly, when HAF and SRF having small particle diameters and large surface areas are added in the same amount, the bulk of the rubber is larger than that of MT carbon. Therefore, it is preferable to use MT carbon in the present invention.

&Lt; Processing aid &

The inventors of the present invention used an excessive amount of carbon in order to proceed with a compound having a high hardness. As described above, the excessive amount of carbon deteriorates the physical properties of the rubber. To solve this problem, a large amount of carbon is used in the present invention, but a processing aid is used in order to maximize dispersion.

Struktol WB-222 or WS-280 available from Schill & Seilacher may be used as the processing aid suitable for the fluorine rubber in the sealing material rubber composition according to the present invention. Each of the above-mentioned processing aids was applied to low temperature fluorine rubber PL-855 and GLT-600S (manufactured by Dupont), and the blending and physical properties were observed. As a result, it was observed that the hardness and elongation were increased by adding 2 phr of the processing aid WB-222 irrespective of the type of fluororubber and the type of carbon. Therefore, it is preferable to use WB-222 as the processing aid in the sealing material rubber composition according to the present invention.

<Cross-linking agent and cross-linking agent>

Generally, examples of the crosslinking method of the fluorine rubber (FKM) include peroxide vulcanization, polyol crosslinking, and polyamine crosslinking. Examples of the crosslinking method of the perfluoroelastomer include triazine crosslinking, benzolate crosslinking, peroxide However, it is preferable to use a peroxide crosslinking agent as a crosslinking system common to both of the perfluoroelastomer (FFKM) and the other fluorine rubber (FKM) in order to proceed the substantial crosslinking . As crosslinking agents usable for peroxide crosslinking, conventionally known ones can be widely used. Specific examples thereof include 2,5-dimethyl-2,5- (t-butylperoxy) hexane (40%) and Perhexa 25B-40 ", 2,5-dimethyl-2,5- (t-butylperoxy) hexane (" Perhexa 25B " Dicumyl peroxide, t-butyl dicumyl peroxide, benzoyl peroxide (available from Nippon Oil & Fats Co., Ltd., Japan) 2,5-dimethyl-2,5- (t-butylperoxy) hexane-3 ("Perhexain 25B" manufactured by Nippon Oil and Fats Co., Ltd.) Butyl peroxybenzoate, 5-di (benzoylperoxy) hexane,?,? '- bis (t-butylperoxy-m-isopropyl) benzene ("Perbutyl P" Para-chlorobenzoyl peroxide, t-butyl perbenzoate, etc. The present invention With respect to the sealing material according to the rubber composition, a crosslinking agent is preferably used in a (dicumyl peroxide) DCP.

Specific examples of the crosslinking agent (crosslinking aid) include triallyl isocyanurate ("TAIC" manufactured by Nippon Kayaku Co., Ltd.), triallyl cyanurate, triallylformate, triallyl trimellitate, N'-m-phenylene bismaleimide, dipropanediyl terephthalate, diallyl phthalate, tetraallyl terephthalamide, and the like. For the sealing rubber composition according to the present invention, triallyl isocyanurate (TAIC) is preferably used as the co-crosslinking agent.

Triallylcyanurate (TAC) is a crosslinking additive commonly used in rubber or resin crosslinking systems. It has excellent storage stability and scorch prevention effect in processing. It is also used in EPDM (ethylene propylene diene monomer), HNBR (hydrogenated nitrile butadiene rubber) , Chlorinated polyethylene (CM), and ethylene vinyl acetate copolymer (EVA). The use of such a co-crosslinking agent not only improves basic physical properties but also imparts excellent heat resistance characteristics.

Also, triallyl isocyanurate (TAIC) is a crosslinking aid suitable for HNBR, EAM (Ethylene vinyl acetate copolymer) and fluorine rubber, and is particularly excellent in compression set durability when applied to fluorine rubber.

<Silica>

Quot; QS10 &quot; (manufactured by Tokuyama Corporation) was used.

Test equipment

(1) Universal testing machine (UTM)

To test the mechanical properties, a model UTM2014S from LABTECH was used.

(2) Oscillating Disk Rheometer (ODR)

In order to investigate the crosslinking characteristics of the chemicals and measure the proper crosslinking time, ODR2013 of LABTECH was used according to ASTM-2084.

(3) Durometer

An IRHD type hardness meter was used to measure hardness.

(4) Aging oven

A moldel aging test chamber aging oven of LABTECH was used to measure heat resistance and oil resistance.

Analytical instrument

(1) Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR)

A Nicolet 6700 model from Thermo Scientific was used to identify the constituents through structural analysis of the material.

(2) Thermo Gravimetric Analyzer (TGA)

A model Q-500 of TA Instrument was used to measure the composition ratio of the material.

(3) Energy Dispersion Spectroscopy (EDS)

INCA EDS from OXFORD was used to identify the constituents of inorganic fillers and additives contained in the material.

(4) Differential Scanning Calorimetry (DSC)

To measure the glass transition temperature (Tg) of the material, a model DSC Q100 from TA Instrument was used.

Characteristic test

(1) Hardness

The hardness of the specimen having a thickness of about 5 to 10 mm was measured with an IRHD type hardness meter according to ASTM D-2240. At this time, the measurement was repeated five times and the average value was taken as longitude.

(2) Tensile strength and elongation

The tensile strength (TB) and elongation (EB) of the specimen were measured by using a die A cutter. At this time, the number of specimens used in the same test was 5, and the measurement conditions were as follows.

Method: ASTM D-412

Die: Die A

Number of specimens (EA): 5

Thickness (mm): 3 ± 0.1

Rate (mm / min): 500

(3) Thermal properties

The rubber sheet was subjected to a test using a die A cutter according to ASTM D-412 and heat-treated in an oven at 250 DEG C for 70 hours, and the change in hardness, tensile strength and elongation was measured. After 5 repeated measurements, the mean value was taken.

(4) Oil resistance

The rubber sheet was tested with a die A cutter according to ASTM D-471 and D-412, The change in hardness, tensile strength, elongation and volume was measured after 70 hours at 150 ° C after oil impregnation. After 5 repeated measurements, the mean value was taken.

Table 2 shows the test lubricant properties. Test lubricant No.1 oil is low swelling oil, No.2 oil is medium swelling oil, and No.3 oil is high swelling oil. In addition, as described in ISO / DIS 1817, No. 1 oil, No. 2 oil and No. 3 correspond to ASTM IRM 9011, IRM 902 and IRM 903, respectively.

(5) Compression Permanent Rowing Rate

A specimen having a thickness of about 10 mm was prepared and measured at 100 캜 and 175 캜 for 24 hours according to ASTM D-395. At this time, the average value was taken after 5 repeated measurements.

(6) Low temperature brittleness

The low temperature brittleness temperature was measured according to ASTM D-746 for certain rubber specimens.

<Examples>

Hereinafter, the sealing rubber composition according to the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

As is apparent from comparison between the following examples and comparative examples, the sealing material made of the sealing material rubber composition according to the present invention is excellent in general physical properties, heat resistance and fuel oil resistance in the natural gas supply equipment, And has various excellent effects as rubber members.

Sealant rubber composition

The sealing material made of the sealing material rubber composition according to the present invention can be produced by a conventionally known method.

Specifically, for example, a rubber component is Soviet (mastication) with a kneading device such as an open roll, a Banbury mixer, a biaxial roll and the like, and a blending component such as a crosslinking agent is further added, Thereby preparing a composition (composition for forming a sealing material for a high-quality natural gas feeder). Then, it is possible to fill the mold of the predetermined shape with the sealing material rubber composition, and obtain a predetermined rubber molded body such as a sealing material by hot press molding. Preferably, the rubber molded body is subjected to secondary crosslinking in an oven or the like for a predetermined period of time. More preferably, secondary crosslinking in air is preferable for reducing the emitted gas and particles.

(Shore A of FKM PL-855 is 80 and 90, respectively, in the case of FKM PL-855, and these are referred to as FP 80 and FP 90, respectively) Was kneaded with an open roll to prepare a sealant rubber composition. Here, MT was used for the carbon black, and QS10 was used for the silica filler. Here, when only carbon black is used as a filler, '(C)' is used, only silica is used as '(Q)', and carbon black and silica are used as '(C / Q)'. ZnO was used for zincification and WB-222 was used as a processing aid. The crosslinking agent used was DCP 98% and the co-crosslinking agent was TAIC 60%. Subsequently, press molding was performed at 165 占 폚 for 15 minutes under a pressure of 5 MPa with a compression vacuum press, and then secondary crosslinking was performed at 200 占 폚 for 20 hours in an electric furnace to obtain an O-ring-formed body (sealing material).

Fig. 1 shows the hardness changes of the sealing materials in Comparative Examples 1 to 4 after pressurization for 14 days. From this, it can be seen that the higher the hardness of the FKM is, the lower the hardness change rate is. That is, the higher the hardness, the greater the change in hardness. Therefore, it is preferable that the FKM in the sealing material rubber composition according to the present invention has a high hardness. In addition, since the change in hardness includes less QS10 than that including carbon black, it is more preferable that QS10 is used. In FP 80 (Q) and FP 90 (Q), hardness of FP 90 (Q) hardly changed from 5 minutes to 10 days. Therefore, FP90 (Q) is particularly preferable.

Fig. 2 shows the volume expansion ratios of the sealing materials in Comparative Examples 1 to 4 and Examples 1 and 2 after pressurization for 14 days. From this, it can be seen that the higher the hardness of the FKM is, the smaller the rate of change of the volume expansion rate is. That is, the higher the hardness of the FKM, the less the volume changes. Also, it is shown that the rate of change of the volume expansion rate decreases as the pressing date becomes longer. In other words, the volume change was not significant as the pressing day was longer. Therefore, it is preferable that the FKM in the sealing material rubber composition according to the present invention has a high hardness.

Table 4 shows the compression set ratio and glass transition temperature.

As shown in Table 4, when carbon black was used for FKM, the compression set ratio was excellent. In the DSC analysis of the FP 80 (C / Q) sealing material, the glass transition temperature was about -29 ° C. when the QS 10 filler was used at 15 phr in the FP 80 (Q) ) The sealing material composition shows about -31 캜. Therefore, the combination of FP 80 (C / Q) sealant was excellent in low temperature characteristics as the glass transition temperature decreased. Similarly, the combination of FP 90 (C / Q) sealant exhibited excellent low-temperature characteristics as the glass transition temperature decreased.

Table 5 shows general properties, heat resistance and fuel oil resistance.

As shown in Table 5, general properties were obtained by using a carbon black / silica (C / Q) filler in combination with a carbon black (C) and a silica (Q) filler in comparison with a tensile strength and elongation . The heat resistance of the carbon black (C) filler was lower than that of the silica (Q) and the carbon black / silica (C / Q) filler in that the carbon black (C) filler had a lower rate of change in tensile strength and elongation. The fuel oil repellency was better than that of the carbon black (C) and silica (Q) filler by using a carbon black / silica (C / Q) filler in combination with lower physical properties such as hardness, tensile strength and elongation percentage. Compression set consistency was better at 100 ℃ and 175 ℃ than when using carbon black (C) and silica (Q) fillers and the combination of carbon black / silica (C / Q) . In addition, the FP 90 (C / Q) (13%) was improved by more than 70% from the FP 90 (Q) (45%). The glass transition temperature (Tg) was obtained by using a carbon black / silica (C / Q) filler in combination with a temperature of -31 to -32 占 폚. It is considered that this is due to the segment movement of the polymer due to the interaction of the silica filler (QS10) with the fluorine rubber polymer. In addition, when the carbon black / silica filler is used in combination with the silica filler alone, the glass transition temperature (Tg) is lowered. Table 4 and Table 5 are compared, and it is possible to lower the compression set ratio by using carbon black / silica (C / Q) filler in combination with a higher hardness. In addition, the low temperature brittleness is improved and it is considered to be a suitable sealing material for high pressure natural gas ball valves.

Claims (19)

In the sealing material rubber composition,
Raw rubber, silica, and a particulate carbon compound,
The raw rubber has a hardness of 90 and is a poly (vinylidene fluoride) / hexafluoropropylene / tetrafluoroethylene terpolymer,
The silica is 2 to 30 parts by weight based on 100 parts by weight of the raw material rubber,
The particulate carbon compound is carbon black having a particle diameter of 201-500 nm and a specific surface area of 9 m ² / g,
A peroxide crosslinking agent as a crosslinking agent; And
A sealant rubber composition further comprising co-crosslinked zero triallyl isocyanurate delete delete delete The method according to claim 1,
Wherein the sealing material rubber composition is 10 to 50 parts by weight of the fine carbon compound relative to 100 parts by weight of the raw rubber. delete The method according to claim 1,
Wherein the sealing material rubber composition is 20 to 40 parts by weight of the particulate carbon compound with respect to 100 parts by weight of the raw rubber. delete delete delete A raw material rubber, silica, and a particulate carbon compound,
The raw rubber has a hardness of 90 and is a poly (vinylidene fluoride) / hexafluoropropylene / tetrafluoroethylene terpolymer,
The silica is 2 to 30 parts by weight based on 100 parts by weight of the raw material rubber,
The particulate carbon compound is carbon black having a particle diameter of 201-500 nm and a specific surface area of 9 m ² / g,
A peroxide crosslinking agent as a crosslinking agent; And
A method of making a sealant rubber composition further comprising co-crosslinked zero triallyl isocyanurate. delete delete delete 12. The method of claim 11,
Wherein the sealing rubber composition is prepared by mixing raw rubber, silica and a particulate carbon compound having 10 to 50 parts by weight of a particulate carbon compound with respect to 100 parts by weight of the raw rubber. delete delete A molded article comprising the sealing rubber composition according to any one of claims 1, 5 and 7. A method for manufacturing a rubber molded article by filling a mold with a sealant rubber composition according to any one of claims 1 to 7, followed by heat molding.

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