TW201307462A - Fiber rubber formulation, fiber rubber composite material and its manufacturing process and application - Google Patents

Abstract

The present invention is related to a fiber rubber formulation and its composite material as well as manufacturing method and application. The fiber rubber formulation of the present invention comprises fluoroelastomer, para-aramid synthetic fiber, and carbon black, and is made from the following steps. Firstly, the fluoroelastomer, carbon black, and additive are blended beforehand and then added with the para-aramid synthetic fiber to form a fluoroelastomer mixture. Afterwards, aiding agent is added to form the fiber rubber by means of forward slicing. The fiber rubber, by means of a modified junction layer, is thermally pressed with a nitrile butadiene rubber and combined into a two-layer fiber rubber composite material. By means of various molding technologies, the composite material can be made into a high precision element material such as a shaft seal, which simultaneously needs the gel part with wear resistance and tear resistance and the gel part with high elasticity and high fitness.

Description

Fiber rubber formula, fiber rubber composite material and its process and application

The present invention relates to a fibrous rubber material which is obtained by a suitable mixing step of an aromatic polyamide synthetic fiber and a fluororubber mixture, and has a high tear strength. The present invention also relates to a fiber rubber composite having the aforementioned fiber rubber material in combination with nitrile rubber which is useful for fabricating component materials requiring two different characteristics. The invention also relates to a method of making a fiber rubber material or a fiber rubber composite material and to the use thereof.

Rotary shaft seals are common high precision components used to seal the space between the shaft, bearing and metal base. The rotary shaft seal of the prior art is mainly composed of a metal shell, a heat-resistant rubber body, a spring, and the like, which is resistant to abrasion by the metal shell and has elasticity of the rubber body, thereby being closely adhered to the metal base and the rotating shaft. To avoid oil and gas leakage inside the bearing. However, the metal casing, the spring and the colloid are not easy to be stably assembled due to different material properties, and when the prior art rotary shaft seal is used for a large-scale machine, once the tool fails, it is usually necessary to cut and destroy the metal casing. Machine maintenance, and once the damage is not easy to reassemble and use, the overall maintenance cost will be greatly improved. For the aforementioned characteristics of the rotating shaft seal, there is a need for a rubber composite material having two different properties. If a rubber composite material having the two characteristics can be manufactured, it can replace the rotary shaft seal of the prior art and reduce maintenance. The cost.

Fluoroelastomer (FKM) is a heat-resistant rubber material currently marketed on the market by DuPont. Mainly, the recent 3M company It is also widely used, based on its heat-resistance and anti-freezing properties, it can be used to manufacture high temperature resistance, corrosion resistance, oil resistance, radiation resistance, seals, gaskets, diaphragms, pumps, pipes and high vacuum, radiation. Precision materials such as wire. However, the hardness and tear strength of fluororubber itself are still insufficient, and the surface energy of fluorocarbon rubber is low (18.5 erg/cm ² ), so it is not easy to combine with other rubbers, and it is easy to produce mixing when blending other components. Both affect the structural strength. Therefore, the tear strength of the fluororubber and its bonding strength with other materials are still to be improved.

Nitrile butadiene rubber is produced by emulsion polymerization of butadiene and acrylonitrile. The nitrile rubber has good oil resistance, good abrasion resistance, high heat resistance and strong adhesion, but its low temperature resistance. Poor and less elastic. In addition, nitrile rubber is very polar, so compatibility with other rubbers is generally not very good. Therefore, the bonding strength between nitrile rubber and other materials still needs to be improved.

Based on the above, it is still known in the art to manufacture a rubber composite material having both characteristics for use in manufacturing a product such as a rotary shaft seal.

In view of the prior art, there is still a lack of a rubber composite material having both anti-wear ability and high adhesion to the object to be sealed. The object of the present invention is to provide an improved rubber composite material which has heat resistance and high elasticity. The rubber material is combined with a rubber material having anti-wearing ability, and the two rubber materials form a high-strength bonding interface structure, and have the effect of resisting external force pulling and being difficult to separate, and conforming to high precision as manufacturing. The material requirements of the component.

In order to achieve the above object, the present invention provides a fiber rubber formulation comprising a fluoroelastomer and an aromatic polyamine synthetic fiber (para-aramid) in an amount of 3% to 8% by weight based on the total fiber rubber. Synthetic fiber), preferably, the aforementioned fiber rubber formulation further comprises carbon black, an additive and an auxiliary agent. Preferably, the aforementioned fluororubber is 100 parts by weight, the carbon black is 20 to 30 parts by weight, and 10 to 20 parts by weight of the additive and 10 to 15 parts by weight of the auxiliary agent.

In another aspect, the present invention also provides a method for producing a fiber rubber, comprising the steps of: providing a premixed compound containing a fluorocarbon rubber; and the weight percentage of the premixed rubber compound based on the fiber rubber as a whole is 3 to 8% of the aromatic polyamine synthetic fibers are mixed to form a fiber rubber compound; and the fiber rubber compound is mixed with an auxiliary agent to form the fiber rubber.

Preferably, the foregoing mixing step of the premixed compound and the para-polyamide polyamide synthetic fiber comprises using the pre-mixed compound and the para-aramid synthetic fiber in a forward-looking manner using a roller kneading machine. Mixing so that the pair of aromatic polyamide synthetic fibers are aligned in the fiber rubber.

Preferably, the above-mentioned aromatic polyamine synthetic fiber is a heat-resistant strong fiber composed of long-chain molecules extending in the axial direction of the fiber, and thus has excellent chemical bond strength.

Preferably, the foregoing step of providing a premixed compound containing a fluororubber comprises kneading a fluorocarbon rubber, carbon black and an additive to form the premixed compound containing the fluororubber, wherein the content of the fluorocarbon rubber It is 100 parts by weight, carbon black is 25 parts by weight, and an appropriate amount of an additive and an auxiliary agent. The proper amount as used herein means sufficient to allow the fluororubber to be crosslinked to have a certain strength, wherein the crosslinking reaction can be carried out by a vulcanizing agent or the like by a vulcanizing agent or the like, and the vulcanization reaction can be achieved by a hot pressing method. Preferably, the additive may be 10 to 20 parts by weight and the auxiliary may be 10 to 15 parts by weight. Since the fibers emit high heat when kneaded in the rubber, in the premixing stage (without fiber addition), in order to avoid premature phenomena, no vulcanization aid is added.

According to the present invention, the aforementioned additives may be, but are not limited to, a processing oil, an activator or a combination thereof; and the aforementioned additives may include, but are not limited to, a bridging aid and a vulcanizing agent.

In another aspect, the present invention also provides a fiber rubber which is produced by the above-described manufacturing method and which has a Shore hardness of 80 to 90 degrees, an elongation of 250 to 300%, and an abrasion amount of 70 to 150 mm ³ .

In another aspect, the present invention also provides a fiber rubber composite material comprising a fiber rubber layer and a nitrile rubber layer tightly bonded to the fiber rubber, wherein the fiber rubber layer comprises a fiber rubber as described above, The nitrile rubber layer comprises a nitrile rubber layer, and the fiber rubber layer and the nitrile rubber layer are tightly bonded by an interface structure, wherein the interface structure is formed by a fluorine rubber, a nitrile rubber and a tackifier, and the interface structure is formed. The strength is greater than 10 kgf/cm ² .

In another aspect, the present invention also provides a method for producing a fiber rubber composite material, comprising the steps of: preparing a blending compatible layer comprising a fiber rubber and a nitrile rubber as described above; And a tackifier is formed by kneading; and the blending compatible layer is hot pressed between a fiber rubber and a nitrile rubber as described above to form the fiber rubber composite.

According to the present invention, the tackifier refers to a material for increasing the adhesion between two contact materials under specific temperature and humidity conditions. For two kinds of materials which are not easily combined, the tackifier can be weakly pressed. A certain strength bond between the two substances is ordered. Tackifiers suitable for use in the present invention include tetrabutylbenzotriazolium.

The rubber composite material of the present invention comprises a fiber rubber layer which is a fluorine-based rubber material having high tear strength, high elongation and heat resistance and high adhesion, which is passed through a high-strength interface structure to make the fiber rubber The layer is combined with a nitrile rubber layer having anti-abrasion capability, wherein the high-strength fiber rubber layer can replace the metal shell of the prior art, and the interface structure can resist the external force to pull the fiber rubber layer and the nitrile rubber layer Not easy to separate. Therefore, the product manufactured by using the rubber composite material of the present invention can meet the needs of related industries. For example, when the rubber composite material of the present invention is used to manufacture a rotary shaft seal, a portion of the fiber colloid layer can be manufactured instead. Part of the metal casing, which facilitates the process of maintenance cutting, increases the convenience of maintenance, and also reduces the manufacturing cost of the shaft seal.

The fiber rubber formulation of the present invention comprises a fluorocarbon rubber and a para-aramid synthetic fiber having a weight percentage of 3% to 8% based on the entire fiber rubber. In a preferred embodiment, the weight percentage of the pair of aromatic polyamide fibers is 5.2%; and the length of the pair of aromatic polyamide fibers is 1 to 6 mm. In another preferred embodiment, the pair of aromatic polyamide synthetic fibers have a length of from 1 to 3 mm.

In a preferred embodiment of the fiber rubber formulation of the present invention, the content of the fluorocarbon rubber is 100 parts by weight (PHR), and the aromatic polyamide polymer fiber is 5.2 weight of the whole fiber rubber. The percentage, carbon black was 25.8 parts by weight, the processing oil was 9.1 parts by weight, and the activator was 6 parts by weight, the antioxidant was 1.82 parts by weight, the bridging aid was 1 part by weight, and the vulcanizing agent was 6 parts by weight.

The fiber rubber of the present invention can be produced by the method for producing the fiber rubber of the present invention by using the above-mentioned fiber rubber. The fiber rubber produced has been tested to have a hardness of 85 degrees and a elongation of 293%. With a tear strength of 46 kgf/cm ² and an abrasion capacity of 146 mm ³ , it meets the needs of alternative metal components.

The fiber rubber composite material of the invention is formed by a fluorine rubber, a nitrile rubber and a tackifier, wherein the weight ratio of the tackifier in the interface structure to the fluorine rubber and the nitrile rubber is 4 : Between 6 and 7: 3. The strength of the interface structure is greater than 10 kgf/cm ² .

In a preferred embodiment of the fiber rubber composite of the present invention, the nitrile rubber layer is a mixture of a nitrile rubber and a tackifier, wherein the weight ratio of the tackifier to the nitrile rubber is between 3:7. Between 8:2.

The tackifier according to the present invention may be a phosphorus-containing heterocyclic compound. In a preferred embodiment of the fiber rubber composite of the present invention, the tackifier is butyl phosphonium benzotriazolate.

The invention will be further illustrated by the following examples, but it should be understood that these examples are for illustrative purposes only and are not to be considered as limiting.

Example

Example 1 Preparation and properties analysis of reinforced heat-resistant fluorocarbon rubber

This example was prepared according to the formulation of Table 1 below by the following method to obtain a reinforced heat-resistant fluororubber.

The reinforced heat-resistant fluororubber of the present embodiment is produced by the following steps: (1) mixing the main component, the additive, and the carbon black in the following Table 2 parameters using a twin-screw compacting machine; (2) adding the reinforcing material (that is, the aromatic polyamine synthetic fiber) is mixed and discharged to obtain a fiber rubber mixture; and (3) the fiber rubber mixture is mixed with an open type roller kneading machine according to the kneading conditions of Table 3 below, and added. Additives, and make the calender and take out the film in a forward direction, obtain a fiber rubber, analyze the forwardness and dispersibility of the fiber in the gel, and analyze the fiber in the vulcanized fiber rubber by SEM of the colloidal section In the case of distribution, the results show that after the addition of the reinforcing material, the vulcanization is carried out and the film is formed in the forward direction, so that the aromatic polyamine synthetic fibers are aligned in the colloid.

The fiber rubber obtained above was further analyzed for various physical properties by the Shore hardness test, CNS3553, and CNS3559, DIN standard test methods, and the results are shown in Table 4 below.

As a result, it was found that the obtained fiber rubber had a tear strength of more than 40 Kgf/cm ² , and it had high hardness (Angstrom A 85 degree) and good elongation (273%, 269%), which is very suitable for application. Manufacturing requires rubber products with high adhesion, such as shaft seal products used in various industrial machines.

Example 2 Preparation and Interfacial Strength Analysis of Fiber Rubber Composites

The purpose of this embodiment is to manufacture a fiber rubber composite material having high adhesion, wear resistance and the like, which is a blend of a high-adhesive fiber rubber sheet and a wear-resistant nitrile rubber sheet. The compatible layer is subjected to hot pressing treatment, and the formed fiber rubber composite material has a fiber rubber layer and a nitrile rubber layer closely bonded to the fiber rubber, wherein an interface structure is formed between the fiber rubber layer and the nitrile rubber layer. . This embodiment further analyzes and compares the interfacial structural strength formed by different blending compatible layer formulations, thereby obtaining a fiber rubber composite material having high interfacial structural strength. The steps of the fiber rubber composite system are detailed as follows.

The fiber rubber (i.e., the fluorine-containing rubber containing fibers) (hereinafter abbreviated as fluorine rubber, and is referred to as F or FKM) in the present embodiment was obtained by the method as described in Example 1.

The nitrile rubber (hereinafter abbreviated as NBR rubber, and is also referred to as N or NBR) in the present embodiment is a condition in which the kneading rubber as a main component has a kneading temperature of less than 100 ° C, a kneading rotation speed of 500 rpm, and a kneading time of 20 minutes. Double drum mixer is mixed.

The blend-compatible layer of the different formulations of the present embodiment is composed of the aforementioned fiber rubber and the aforementioned nitrile rubber and/or a tackifier [butyl phosphonium benzotriazolate] ( Zeonet PB) (hereinafter referred to as PB) is formed by kneading. As shown in Figure 1, blended compatible layers (FKM/NBR, FKM/NBR/PB, FKM/NBR/PB) of different formulations were placed in a fiber rubber (FKM) and a nitrile rubber (NBR/NBR+). The PB) sheet is subjected to hot press vulcanization to form a fiber rubber composite material having a two-layer structure. The detailed production steps of various fiber rubber composite test pieces are as follows:

a. Control composite (F/N):

The fluorine rubber and the NBR rubber were directly subjected to hot press vulcanization to form a test piece (F/N).

b. Fiber rubber composites (F/A/N) combined with a common adhesive:

(1) Preparation of fluorine rubber and NBR rubber sheet; (2) Coating of adhesive on NBR rubber surface (Chemlok-Lord 6153, 615TX, 2132 or Nafion And (3) hot-vulcanized and formed the fluorine rubber and NBR rubber into a test piece (F/A/N), please refer to the area A of Figure 1.

c. Fiber rubber composite (F/FN/N) combined with a blend compatible layer (FN):

(1) Firstly mix the fluorine rubber and NBR rubber with a weight ratio of 5:5 in various ratios to form a blending compatible layer; (2) Place the blending compatible layer in the fluorine rubber and NBR rubber. Between the sheets; and (3) FCC and NBR rubber hot-pressed vulcanization to form test pieces (F/FN/N), please refer to Zone B of Figure 1.

d. Fiber rubber composite (F/FN-PB/N) combined with a blend compatible layer (FN-PB):

(1) firstly mixing the fluorine rubber of the weight ratio of 5:5 with the NBR rubber in a compacting machine, taking 100 parts by weight, and adding PB of 2, 4 and 7 parts by weight to prepare a blending compatible layer; 2) placing the blending compatible layer between the fluorine rubber and the NBR rubber film; and (3) forming the test piece (F/FN-PB/N) by hot pressing vulcanization of the fluorine rubber and the NBR rubber, please refer to the reference drawing. Zone 1 of Zone 1.

e. Another fiber rubber composite (F/FN-PB/N-PB) combined with a blend compatible layer (FN-PB):

(1) firstly mixing a fluorine rubber and a NBR rubber having a weight ratio of 5:5 by a weaving machine, taking 100 parts by weight, and further adding PB of 2, 4 and 7 parts by weight to prepare a blending compatible layer; (2) 100 parts by weight of unvulcanized NBR rubber is blended with PB of 3, 5 and 6 parts to form NBR+BP rubber; (3) The blending compatible layer is placed in fluorine rubber and NBR-BP rubber And (4) hot-vulcanization of fluorine rubber and NBR-BP rubber into a test piece (F/FN-PB/N-PB), please refer to the D area of Figure 1.

The test piece obtained above was further tested by the standard test CNS5812 K6508/ASTM-D903, and as shown in the following Table 5, the interface strength of the fiber rubber composite material produced according to the present invention was greater than 10 kgf/cm ² and as high as 13.4. Kgf/cm ² shows that the technique of the present invention overcomes the problem that the fluorine-based rubber is not easily bonded to other materials. In addition, as shown in Table 5, where the failure mode is the location where the test process is damaged, if the damage is the interface, it is marked as the interface; and if the damage is the aforementioned fluorine rubber and NBR rubber, it is marked as the material. The results show that when the PB in the blended compatible layer is more than 4 parts by weight, the interface strength is greater than 12 kgf/cm ² , and the occurrence of the failure behavior will be changed from the "interface" to the "material", that is, the fluorine rubber and The strength of the NBR rubber is higher than that of the fluorine rubber and the NBR rubber material itself, confirming that the fiber rubber composite of the present invention has extremely high interfacial strength.

Figure 1 is a schematic diagram of the combination of different fiber composite materials, wherein FKM represents a fiber rubber layer, NBR represents a nitrile rubber layer, Adhesive represents an adhesive, FKM/NBR, FKM/NBR/PB represents a blended compatible layer of different formulations, And NBR+PB represents a nitrile rubber layer mixed with a tackifier.

Claims (19)

A fiber rubber formulation comprising a fluoroelastomer and a para-aramid synthetic fiber having a weight percentage of 3% to 8% based on the total fiber rubber. The fiber rubber formulation according to claim 1, wherein the weight percentage of the aromatic polyamine synthetic fiber is 5.2% based on the fiber rubber as a whole. The fiber rubber formulation of claim 2, wherein the pair of aromatic polyamide fibers have a length of from 1 to 6 mm. The fiber rubber formulation of any one of claims 1 to 3, which further comprises carbon black, an additive, and an auxiliary. The fiber rubber formulation according to claim 4, wherein the fluorocarbon rubber is 100 parts by weight and the carbon black is 20 to 30 parts by weight. A fiber rubber formulation as described in claim 5, wherein the additive is a processing oil, an activator or a combination thereof; and the adjuvant comprises a bridging aid and a vulcanizing agent. The fiber rubber formulation according to claim 6, wherein the content of the fluorocarbon rubber is 100 parts by weight, the aromatic polyamine synthetic fiber is 5.2% by weight of the entire fiber rubber, and the carbon black is 25.8 parts by weight. The oil was 9.1 parts by weight and the activator was 6 parts by weight, the antioxidant was 1.82 parts by weight, the bridging aid was 1 part by weight, and the vulcanizing agent was 6 parts by weight. A method for producing a fiber rubber, comprising: providing a premixed compound containing a fluororubber, which comprises a fluorocarbon rubber; and the weight ratio of the premixed rubber compound to an integral fiber rubber is 3 to 8 % of the aromatic polyamide synthetic fibers are mixed to form a fiber rubber compound; and the fiber rubber compound is mixed with an auxiliary agent to form the fiber rubber. The method for producing a fiber rubber according to claim 8, wherein the step of mixing the premixed compound with the aromatic polyamine synthetic fiber comprises synthesizing the premixed compound with an aromatic polyamine. The fibers are mixed in a forward-feeding manner using a roller kneader to thereby align the pair of aromatic polyamide synthetic fibers in the fiber rubber. The method for producing a fiber rubber according to claim 9, wherein the step of providing a premixed compound containing a fluororubber comprises kneading a fluorocarbon rubber, carbon black, and an additive to form the fluorocarbon rubber. A premixed compound in which the content of the fluororubber is 100 parts by weight and the carbon black is 25 parts by weight. The method for producing a fibrous rubber according to claim 10, wherein the additive comprises a processing oil and an activator; and the auxiliary agent comprises an antioxidant, a bridging aid, and a vulcanizing agent. The method for producing a fiber rubber according to claim 11, wherein the content of the fluorocarbon rubber is 100 parts by weight, the aromatic polyamine synthetic fiber is 5.2% by weight of the whole fiber rubber, and the carbon black is 25.8 parts by weight. The processing oil was 9.1 parts by weight and the activator was 6 parts by weight, the antioxidant was 1.82 parts by weight, the bridging aid was 1 part by weight, and the vulcanizing agent was 6 parts by weight. A fiber rubber produced by the production method according to any one of claims 8 to 12, which has a Shore hardness of 80 to 90 degrees, an elongation of 250 to 300%, and an abrasion amount of 70 to 150 mm. ³ . A fiber rubber composite material comprising a fiber rubber layer and a nitrile rubber layer tightly bonded to the fiber rubber, wherein the fiber rubber layer comprises a fiber rubber according to claim 13 of the patent application, the nitrile The rubber layer comprises a nitrile rubber layer, and the fiber rubber layer and the nitrile rubber layer are tightly bonded by an interface structure formed by a fluorine rubber, a nitrile rubber and a tackifier, and the strength of the interface structure More than 10 kgf/cm ² . The fiber rubber composite material according to claim 14, wherein the weight ratio of the tackifier to the fluorine rubber and the nitrile rubber in the interface structure is between 4:6 and 7:3. The fiber rubber composite material according to claim 15, wherein the nitrile rubber layer is a mixture of a nitrile rubber and a tackifier. The fiber rubber composite material according to claim 16, wherein the weight ratio of the tackifier to the nitrile rubber in the nitrile rubber layer is between 3:7 and 8:2. The fiber rubber composite material according to any one of claims 14 to 17, wherein the tackifier is a phosphorus-containing heterocyclic compound. A method for producing a fiber rubber composite material, comprising: preparing a blending compatible layer, wherein the blending compatible layer is a fiber rubber and a nitrile rubber, and a tackifier as described in claim 13 The kneading is formed; and the blended compatible layer is placed between a fiber rubber as described in claim 13 and a sheet of nitrile rubber to be hot pressed to form the fiber rubber composite.