Hot jet silica gel hose sheath material and preparation method thereof

Abstract

The invention discloses a hot air injection silica gel hose sheath material which is prepared from the following raw materials in parts by weight: 95-105 parts of natural raw rubber, 0-15 parts of an active system, 5-10 parts of an anti-aging system, 60-75 parts of a reinforcing system and 10-15 parts of a plasticizing system, 1-3 parts of a promoting system and 2-4 parts of a cross-linking agent; the natural raw rubber is a combination of 1 # standard natural raw rubber and constant-viscosity natural raw rubber. The invention discloses a hot air injection silica gel hose sheath which comprises a braid layer, an inner rubber strip and an outer rubber strip, the inner rubber strip is spirally supported in the braid layer, the outer rubber strip is spirally wound outside the braid layer, and the outer rubber strip and the inner rubber strip are overlapped; the inner rubber strip and the outer rubber strip are rubber strips made of hot air injection silica gel hose sheath materials. The performance of the hot air injection silica gel hose sheath material reaches the optimal state, the hot air injection silica gel hose sheath material is prepared into a sheath for an air injection starting hose, and the stability and durability of the performance of a hot air injection starting hose product are effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of rubber materials and relates to a thermal jet silicone hose sheath material and its preparation method. Background Technology

[0002] Aircraft and airport air supply equipment vehicles primarily start aircraft engines by outputting low-pressure, high-flow compressed air. They can also provide auxiliary air supply for aircraft inspections or air conditioning. The equipment consists of a vehicle chassis, compressor unit, housing assembly, air supply assembly, and electrical system. The vehicle is also equipped with a heating system that generates heat, including waste heat supply devices and independent heat source devices, which is then delivered to the aircraft via jet starter hoses to meet various needs. Jet starter hoses require continuous high-temperature resistance, typically operating at around 200°C, with instantaneous operating temperatures reaching around 250°C. High-pressure, high-temperature hot air is passed through the hose, and during use, it undergoes frequent free bending, friction, stretching, and tearing with the ground or other media. Jet starter hoses are generally made of silicone or fluorosilicone. High-temperature resistance is a strength of silicone, while resistance to friction, stretching, and tearing is a weakness. Fluorosilicone has similar properties to silicone. Therefore, matching a suitable sheath to the silicone or fluorosilicone hose is the only way to solve the above problems. The sheath must be lightweight and have good heat dissipation. In order to meet the harsh operating environment of the jet starter hose, the hose sheath must also have good wear resistance, high and low temperature resistance, and tensile and tear resistance. Only in this way can the hose sheath be used under harsh conditions. The sheath and hose are used in combination, complementing each other's strengths and compensating for each other, so as to ensure the use of the hot jet starter hose under the above harsh conditions. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing silicone or fluorosilicone hoses and provide a thermal jet hose sheath material and its preparation method. By designing an optimal sheath material formula, raw materials with different properties are mixed to eliminate negative chemical reactions between them, thus maximizing their advantages and minimizing their disadvantages. Through parameter control of the product manufacturing process and key process conditions, the performance of the thermal jet hose sheath material is optimized. When this material is made into a sheath and used in jet starter hoses, it can meet the requirements of aviation hot air source and high-frequency use, effectively improving the stability and durability of the thermal jet starter hose product performance.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A thermal jet silicone hose sheath material, which is made from raw materials comprising the following parts by weight:

[0006] 95-105 parts natural raw rubber;

[0007] 10-15 parts of the active system;

[0008] Anti-aging system 5-10 copies;

[0009] 60-75 parts of the reinforcement system;

[0010] 10-15 parts of plasticizer system;

[0011] Promote the system 1-3 copies;

[0012] Crosslinking agent 2-4 parts.

[0013] Preferably, the thermal jet silicone hose sheath material is made from raw materials comprising the following parts by weight:

[0014] 95-105 parts natural raw rubber;

[0015] 10-12 parts of the active system;

[0016] Anti-aging system 8-10 parts;

[0017] 60-72 parts of the reinforcement system;

[0018] 10-12 parts of plasticizer system;

[0019] Promote the system to 2.5-3 parts;

[0020] Crosslinking agent 2-4 parts.

[0021] More preferably, the thermal jet silicone hose sheath material is made from raw materials comprising the following parts by weight:

[0022] 99 parts natural raw rubber;

[0023] 12 portions of the active system;

[0024] Nine anti-aging systems;

[0025] 70-72 parts of the reinforcement system;

[0026] 12 parts of plasticizer system;

[0027] Promotion system 2.5 copies;

[0028] Three parts of crosslinking agent.

[0029] The natural raw rubber is a combination of standard No. 1 natural raw rubber and constant viscosity natural raw rubber in a weight ratio of 1:1 to 3:1.

[0030] Preferably, the natural raw rubber is a combination of standard No. 1 natural raw rubber and constant viscosity natural raw rubber in a weight ratio of 2:1.

[0031] This invention uses standard natural raw rubber #1 and constant viscosity natural raw rubber as natural raw rubber, which have the best mixing performance with reinforcing materials, extremely low loss rate, and good retention of physical properties.

[0032] The active system is a combination of zinc oxide and stearic acid in a weight ratio of 4:1 to 6:1.

[0033] Preferably, the active system is a combination of zinc oxide and stearic acid in a weight ratio of 5:1.

[0034] The zinc oxide mentioned is highly active zinc oxide with a purity of 99.99% or higher.

[0035] The anti-aging system is a combination of antioxidant 445, antioxidant 4010NA and protective paraffin 9108 in a weight ratio of 1:1:1 to 1:2:3.

[0036] Preferably, the anti-aging system is a combination of anti-aging agent 445, anti-aging agent 4010NA and protective paraffin 9108 in a weight ratio of 1:1.5:2.

[0037] The reinforcing system is a combination of carbon black and white lubricating raw materials in a weight ratio of 3:1 to 5:1.

[0038] Preferably, the reinforcing system is a combination of carbon black and white lubricating raw materials in a weight ratio of 4:1.

[0039] The carbon black is a combination of medium-abrasion resistant carbon black 220 and thermal cracking carbon black 990 in a weight ratio of 2:1 to 4:1.

[0040] Preferably, the carbon black is a combination of medium-strength abrasion-resistant carbon black 220 and thermal cracking carbon black 990 in a weight ratio of 3:1.

[0041] The white lubricating material mentioned is talc powder.

[0042] The talc powder has a particle size of 1000 mesh.

[0043] The plasticizing system is a combination of aromatic oil, adhesive RS and adhesive RA in a weight ratio of (3-5):1:1. The plasticizing system has the best mixing performance with natural raw rubber materials, with the advantages of extremely low volatility and good retention of physical properties.

[0044] Preferably, the plasticizing system is a combination of aromatic oil, adhesive RS and adhesive RA in a weight ratio of 4:1:1.

[0045] The aforementioned accelerator system is a combination of accelerator DTDM and accelerator TT in a weight ratio of 3:1 to 5:1.

[0046] Preferably, the promoting system is a combination of accelerator DTDM and accelerator TT in a weight ratio of 4:1.

[0047] The crosslinking agent is a combination of peroxide and sulfur in a weight ratio of 1:1 to 1:3.

[0048] Preferably, the crosslinking agent is a combination of peroxide and sulfur in a weight ratio of 1:2.

[0049] The peroxide is DCP or bis(2,5-diphenyl)propoxide.

[0050] Another object of the present invention is to provide a method for preparing the aforementioned thermal jet silicone hose sheath material, comprising the following steps:

[0051] Step (1) Preparation of masterbatch through mixing: When the temperature of the internal mixer reaches 50℃~70℃, add natural raw rubber and plasticize for 240 seconds~360 seconds, add the anti-aging system and mix, raise the bolt once, add the reinforcing system and plasticizing system, raise the bolt twice, and wait for the temperature of the rubber compound to reach 115℃~125℃. Discharge the material from the mill, open the mill to produce sheets, cool with water to obtain masterbatch sheets, and let them stand for more than 12 hours.

[0052] Step (2), two-stage mixing preparation of compounded rubber: When the temperature of the internal mixer reaches 50℃~70℃, add the masterbatch rubber sheet and plasticize for 300 seconds~360 seconds, add the active system for mixing, and lift the plug once. Add the accelerator system and crosslinking agent for mixing, and lift the plug twice. When the temperature of the rubber compound reaches 95℃~105℃, discharge the material from the internal mixer and put the rubber compound into the open mill. Turn the material over for 240 seconds~300 seconds, adjust the roller gap to 7~10mm, and the rubber compound is sheeted out. Cool it with water to obtain the silicone tube sheath compounded rubber material, and let it stand for more than 24 hours.

[0053] In step (1), when the temperature of the internal mixer reaches 50℃~70℃, natural raw rubber is added and plasticized for 300 seconds.

[0054] Another object of the present invention is to provide a thermal jet silicone hose sheath, comprising a braided layer, an inner rubber strip and an outer rubber strip, wherein the inner rubber strip is spirally supported inside the braided layer, and the outer rubber strip is spirally wound around the outside of the braided layer, and the outer rubber strip overlaps with the inner rubber strip; both the inner and outer rubber strips are rubber strips made of the thermal jet silicone hose sheath material.

[0055] Another object of the present invention is to provide a method for preparing the aforementioned thermal jet silicone hose sheath, comprising the following steps:

[0056] Step (1): Control the temperature of the extruder body to 70℃~80℃ and the temperature of the screw to 60℃~70℃. The silicone hose sheath compound rubber material is extruded and formed by the extruder to obtain a rubber strip. The rubber strip is wound on the mandrel once with a pitch of 60~80mm. Polyester or aramid yarn is used to braid the inner rubber strip to obtain a braided shape with a braiding angle of 25 degrees~45 degrees. Then, the rubber strip is wound a second time on the outside of the braided layer to form an outer rubber strip. The outer rubber strip overlaps with the inner rubber strip to obtain a sheath semi-finished product. The sheath semi-finished product is left to stand for more than 1 hour.

[0057] Step (2): The sheath semi-finished product is vulcanized in a vulcanizing tank. The vulcanization conditions are: temperature 140℃~150℃, pressure 0.4~0.5MPa, time 110~120 minutes.

[0058] Step (3): Remove the core rod to obtain the sheath product.

[0059] In step (1), the width of the adhesive strip is 20-30 mm.

[0060] Physical property standards of the thermal jet silicone hose sheath material described in this invention:

[0061]

[0062] Performance standards for the thermal jet silicone hose sheath product described in this invention:

[0063]

[0064] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0065] (1) The present invention uses a combination of No. 1 standard natural raw rubber and constant viscosity natural raw rubber, which has the best mixing performance with the reinforcing material, the advantage of extremely low loss rate, and good retention of physical properties and wear resistance.

[0066] (2) The present invention uses a mixture of aromatic oil, adhesive RS and adhesive RA as a plasticizing system. The plasticizing system has the best mixing performance with natural raw rubber materials, with the advantages of extremely low volatility and good retention of physical and adhesive properties.

[0067] (3) The present invention uses carbon black and white lubricating raw materials as a reinforcing system, which effectively improves the mixing and dispersibility of the reinforcing material and natural raw rubber. The reinforcing system uses carbon black and white lubricating raw materials as a mixture, which effectively improves the mixing and dispersibility of the reinforcing material and the plasticizing system, and effectively improves the physical properties and aging properties of the material.

[0068] (4) The present invention uses a mixture of accelerator DTDM and accelerator TT as the accelerator system and a mixture of peroxide and sulfur as the crosslinking system, which has good physical property retention.

[0069] (5) The silicone hose sheath material preparation process of the present invention includes a first stage of mixing to prepare masterbatch, in which an anti-aging system is preferentially mixed with natural raw rubber, which effectively improves the overall dispersibility and uniformity of the anti-aging system of the material. The second stage of mixing to prepare compounded rubber uses an active system to be mixed with natural masterbatch, which effectively improves the overall dispersibility and uniformity of the active system of the material, and ultimately improves the retention of the physical properties and aging properties of the product.

[0070] (6) The silicone tube sheath material of the present invention adopts a first-stage mixing premixed rubber with a temperature of 25±5℃, humidity ≤70%, and a storage time of no more than 6 months, and a second-stage mixing premixed rubber with a temperature of 25±5℃, humidity ≤70%, and a storage time of no more than 3 months, which effectively improves the dispersibility, mixing properties and stability of the material. Attached Figure Description

[0071] Figure 1 This is a schematic diagram of the structure of the silicone hose sheath for thermal jetting.

[0072] Figure 1 In the middle, 1-woven layer, 2-outer rubber strip. Detailed Implementation

[0073] The technical solution of the present invention will be further illustrated by using examples.

[0074] Example 1

[0075] Table 1. Material formulations (parts by weight) for Example 1, Comparative Examples 1a-1c

[0076]

[0077] Note: Zinc oxide is highly active zinc oxide with a purity of 99.99%, the same below; the PCA value of aromatic oil is ≤10%, the same below.

[0078] A thermal jet silicone hose sheath material, the raw materials and their weight proportions are shown in Table 1, and the preparation method of the thermal jet silicone hose sheath material includes the following steps:

[0079] Step (1) Preparation of masterbatch through mixing: When the temperature of the internal mixer reaches 60℃, add No. 1 standard smoked sheet and constant viscosity natural rubber CV60 and plasticize for 300 seconds. Add antioxidant 445, antioxidant 410NA and protective wax 9108 and mix. Raise the plug once, add medium-abrasion resistant carbon black 220, thermal cracking carbon black 990, aromatic oil, adhesive RS and adhesive RA. Raise the plug twice. When the temperature of the rubber compound reaches 120℃, discharge the material. The open mill produces sheets, which are cooled with water to obtain masterbatch sheets. Let them stand for 16 hours.

[0080] Step (2), two-stage mixing preparation of compounded rubber: When the temperature of the internal mixer reaches 65℃, add the masterbatch rubber sheet and plasticize for 300 seconds, add zinc oxide and stearic acid for mixing, raise the plug once, add accelerator DTDM, accelerator TT and S-80, DCP for mixing, raise the plug twice, wait for the rubber temperature to reach 100℃, discharge the internal mixer, the rubber material enters the open mill, turn the material for 240 seconds, adjust the roller gap to 9mm, the rubber material is sheeted out, water-cooled, and the silicone tube sheath compounded rubber material is obtained, and left to stand for 24 hours.

[0081] like Figure 1 As shown, a thermal jet silicone hose sheath includes a braided layer, an inner rubber strip, and an outer rubber strip. The inner rubber strip is spirally supported inside the braided layer, and the outer rubber strip is spirally wound around the outside of the braided layer. The method for preparing the thermal jet silicone hose sheath includes the following steps:

[0082] Step (1): Set the extruder body temperature to 75℃ and the screw temperature to 65℃. The silicone hose sheath compound is extruded into a rubber strip with a width of 20mm and a thickness of 5mm. The rubber strip is wound around the mandrel to form an inner rubber strip with a pitch of 60mm. Then, 2200D polyester yarn is used to weave the inner rubber strip to form a braided layer 1 with a braiding angle of 30 degrees. The rubber strip is wound around the braided layer a second time to form an outer rubber strip 2. The outer rubber strip overlaps with the inner rubber strip. The pitch of the outer rubber strip is the same as that of the inner rubber strip, which is 60mm. The sheath semi-finished product is obtained and left to stand for 2 hours for later use.

[0083] Step (2): The sheath semi-finished product is sent into the vulcanizing tank for vulcanization. The vulcanization temperature is 145℃, the vulcanization pressure is 0.4~0.5MPa, and the vulcanization time is 120 minutes.

[0084] Step (3): After vulcanization, remove the core rod to obtain the sheath product.

[0085] Comparative Example 1a

[0086] A thermal jet silicone hose sheath material, the raw materials and weight parts of which are shown in Table 1, is prepared according to the method of Example 1. The thermal jet silicone hose sheath material is then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 1.

[0087] Comparative Example 1b

[0088] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 1, is prepared according to the method of Example 1. The thermal jet silicone hose sheath material is then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 1.

[0089] Comparative Example 1c

[0090] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 1, is prepared according to the method of Example 1. The thermal jet silicone hose sheath material is then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 1.

[0091] The properties of the thermal jet silicone hose sheath materials prepared in Example 1 and the three comparative examples are shown in Table 2.

[0092] Table 2. Performance of the thermal jet silicone hose sheath materials prepared in Example 1 and the three comparative examples

[0093]

[0094] The performance analysis led to the following conclusions:

[0095] (1) When the ultra-wear-resistant carbon black 220 in Example 1 was replaced with an equal amount of high-wear-resistant carbon black 330, the wear resistance of the material (Comparative Example 1a) did not meet the requirements. Specifically, the wear resistance was reduced and the friction coefficient was increased. At the same time, the hardness and strength of the material were also reduced.

[0096] (2) When the ultra-abrasion-resistant carbon black 220 in Example 1 was replaced with mixed gas carbon black in equal amounts, the tear strength and abrasion resistance of the material (Comparative Example 1b) decreased, the coefficient of friction increased, the change in elongation at break under low temperature aging did not meet the requirements, and the hardness and strength also decreased.

[0097] (3) When the ultra-abrasion resistant carbon black 220 in Example 1 is replaced with channel black, i.e. fumed silica alone, the tear strength and abrasion resistance of the material (Comparative Example 1c) are reduced, the coefficient of friction is increased, the compression deformation is increased, and the changes in elongation at break under low and high temperature aging do not meet the requirements.

[0098] Table 3. Performance of the sheaths prepared in Example 1 and the three comparative examples

[0099]

[0100] Based on the performance analysis of the sheathing product, the following conclusions were drawn:

[0101] (1) When the ultra-abrasion-resistant carbon black 220 in Example 1 is replaced with an equal amount of high abrasion-resistant carbon black 330, the adhesion between the sheath rubber and the polyester tends to decrease.

[0102] (2) When the ultra-abrasion resistant carbon black 220 in Example 1 is replaced with mixed gas carbon black in equal amounts, the adhesion between the sheath rubber and the polyester tends to decrease.

[0103] Example 2

[0104] Table 4. Material formulations (parts by weight) for Example 2, Comparative Examples 2a-2c

[0105]

[0106] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 4, is prepared by the same method as in Example 1. Using the thermal jet silicone hose sheath material obtained in this example as the adhesive, a thermal jet silicone hose sheath is prepared according to the method in Example 1.

[0107] Comparative Example 2a

[0108] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 4, was prepared according to the method of Example 2. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 2.

[0109] Comparative Example 2b

[0110] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 4, was prepared according to the method of Example 2. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 2.

[0111] Comparative Example 2c

[0112] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 4, was prepared according to the method of Example 2. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 2.

[0113] The properties of the thermal jet silicone hose sheath materials prepared in Example 2 and the three comparative examples are shown in Table 5.

[0114] Table 5. Performance of the thermal jet silicone hose sheath materials prepared in Example 2 and the three comparative examples.

[0115]

[0116] The performance analysis led to the following conclusions:

[0117] (1) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of semi-reinforcing 774, the material (Comparative Example 2a) has low tear resistance, reduced wear resistance, increased friction coefficient, and large changes in elongation at break under high and low temperature aging. These properties do not meet the above standard requirements, and the hardness and strength are also reduced.

[0118] (2) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of general carbon black 660, the material (Comparative Example 2b) has low tear resistance, reduced wear resistance, increased friction coefficient, and large changes in elongation at break under high and low temperature aging. These properties do not meet the above standard requirements, and the hardness and strength are also reduced.

[0119] (3) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of white carbon black, the wear resistance of the material (Comparative Example 2c) is reduced, the friction coefficient is increased, and the elongation at break after high and low temperature aging changes significantly. These properties do not meet the above standard requirements, and the hardness and strength are also reduced.

[0120] Table 6. Performance of the sheaths prepared in Example 2 and the three comparative examples

[0121]

[0122] Based on the performance analysis of the sheathing product, the following conclusions were drawn:

[0123] (1) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of semi-reinforcing 774, the adhesion between the sheath rubber and the polyester tends to decrease.

[0124] (2) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of general carbon black 660, the adhesion between the sheath rubber and the polyester tends to decrease.

[0125] (3) When the thermal cracking carbon black 990 of Example 2 is replaced with an equal amount of white carbon black, the adhesion between the sheath rubber and the polyester tends to decrease.

[0126] Example 3

[0127] Table 7. Material formulations (parts by weight) for Example 3, Comparative Examples 3a-3c

[0128]

[0129] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 7, is prepared by the same method as in Example 1. Using the thermal jet silicone hose sheath material obtained in this example as the adhesive, a thermal jet silicone hose sheath is prepared according to the method in Example 1.

[0130] Comparative Example 3a

[0131] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 7, was prepared according to the method of Example 3. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 3.

[0132] Comparative Example 3b

[0133] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 7, was prepared according to the method of Example 3. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 3.

[0134] Comparative Example 3c

[0135] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 7, was prepared according to the method of Example 3. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 3.

[0136] The properties of the thermal jet silicone hose sheath materials prepared in Example 3 and the three comparative examples are shown in Table 8.

[0137] Table 8. Performance of the thermal jet silicone hose sheath materials prepared in Example 3 and the three comparative examples

[0138]

[0139] The performance analysis led to the following conclusions:

[0140] (1) When the talc powder in Example 3 was replaced with clay in equal amounts, the wear resistance of the material (Comparative Example 3a) decreased, the coefficient of friction increased, the elongation at break under high and low temperature aging changed significantly, and the high temperature compressive deformation was significant. These properties did not meet the above standard requirements, and the tear strength and tensile strength also decreased.

[0141] (2) When the talc powder in Example 3 is replaced with an equal amount of calcium carbonate, the material (Comparative Example 3b) has low tear resistance, reduced wear resistance, increased friction coefficient, large changes in elongation at break under high and low temperature aging, and large high temperature compressive deformation. These properties do not meet the above standard requirements, and the tensile strength is also reduced.

[0142] (3) When the talc powder in Example 3 was replaced with silica in equal amounts, the wear resistance of the material (Comparative Example 3c) decreased and the coefficient of friction increased. These properties did not meet the above standard requirements, and the low-temperature aging elongation at break changed significantly and barely met the standard.

[0143] Table 9. Performance of the sheaths prepared in Example 3 and the three comparative examples

[0144]

[0145] Based on the performance analysis of the sheathing product, the following conclusions were drawn:

[0146] (1) When the talc powder in Example 3 is replaced with an equal amount of clay, the adhesion between the sheath rubber and the polyester tends to decrease.

[0147] (2) When the talc powder in Example 3 is replaced with an equal amount of calcium carbonate, the adhesion between the sheath rubber and the polyester tends to decrease.

[0148] Example 4

[0149] Table 10. Material formulations (parts by weight) for Example 4, Comparative Examples 4a-4c

[0150]

[0151] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 10, is prepared by the same method as in Example 1. Using the thermal jet silicone hose sheath material obtained in this example as the adhesive, a thermal jet silicone hose sheath is prepared according to the method in Example 1.

[0152] Comparative Example 4a

[0153] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 10, was prepared according to the method of Example 4. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 4.

[0154] Comparative Example 4b

[0155] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 10, was prepared according to the method of Example 4. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 4.

[0156] Comparative Example 4c

[0157] A thermal jet silicone hose sheath material, the composition and weight parts of which are shown in Table 10, was prepared according to the method of Example 4. The thermal jet silicone hose sheath material was then used as the adhesive to prepare the thermal jet silicone hose sheath according to the method of Example 4.

[0158] The properties of the thermal jet silicone hose sheath materials prepared in Example 4 and the three comparative examples are shown in Table 11.

[0159] Table 11. Performance of the thermal jet silicone hose sheath materials prepared in Example 4 and the three comparative examples

[0160]

[0161] The performance analysis led to the following conclusions:

[0162] (1) When the aromatic oil in Example 4 is replaced with an equal amount of paraffin oil, the tear strength and tensile strength of the material (Comparative Example 4a) are lower, the wear resistance is reduced, the friction coefficient is increased, the elongation at break changes significantly under high and low temperature aging, and the compressive deformation is larger. These properties do not meet the above standard requirements, and the hardness is also reduced.

[0163] (2) In Comparative Example 4b, the aromatic oil in Example 4 was replaced with naphthenic oil in equal amounts. The wear resistance of the material (Comparative Example 4b) was reduced, the friction coefficient was increased, the elongation at break under high and low temperature aging changed significantly, and the compressive deformation was large. These properties did not meet the above standard requirements, and the tear strength and tensile strength were also reduced.

[0164] (3) In Comparative Example 4c, the aromatic oil in Example 4 was replaced with an equal amount of machine oil. The wear resistance of the material (Comparative Example 4c) was reduced, the friction coefficient was increased, the elongation at break under high and low temperature aging changed significantly, and the compressive deformation was large. These properties did not meet the above standard requirements, and the tear strength and tensile strength were also reduced.

[0165] Table 12. Performance of the sheaths prepared in Example 4 and the three comparative examples

[0166]

[0167] Based on the performance analysis of the sheathing product, the following conclusions were drawn:

[0168] (1) When the aromatic oil in Example 4 was replaced with an equal amount of paraffin oil, the adhesion between the sheath rubber and the polyester decreased significantly.

[0169] (2) In Comparative Example 4b, the aromatic oil in Example 4 was replaced with naphthenic oil in equal amounts, and the adhesion between the sheath rubber and the polyester showed a decreasing trend.

[0170] (3) In Comparative Example 4c, the aromatic oil in Example 4 was replaced with an equal amount of machine oil, and the adhesion between the sheath rubber and the polyester was significantly reduced.

Claims

1. A thermal jet silicone hose sheath material, characterized in that: It is made from the following ingredients in parts by weight: 95-105 parts natural raw rubber; 10-15 parts of the active system; Anti-aging system 5-10 copies; 60-75 parts of the reinforcement system; 10-15 parts of plasticizer system; Promote the system by 1-3 copies; 2-4 parts of crosslinking agent; The natural raw rubber is a combination of standard natural raw rubber #1 and constant viscosity natural raw rubber in a weight ratio of 1:1 to 3:1; the active system is a combination of zinc oxide and stearic acid in a weight ratio of 4:1 to 6:1; the anti-aging system is a combination of antioxidant 445, antioxidant 4010NA and protective paraffin wax 9108 in a weight ratio of 1:1:1 to 1:2:3; the reinforcing system is a combination of carbon black and white lubricating raw materials in a weight ratio of 3:1 to 5:1; the carbon black is a combination of medium-duty wear-resistant carbon black 220 and thermal cracking carbon black 990 in a weight ratio of 2:1 to 4:1; the plasticizing system is a combination of aromatic oil, adhesive RS and adhesive RA in a weight ratio of (3-5):1:1; the accelerator system is a combination of accelerator DTDM and accelerator TT in a weight ratio of 3:1 to 5:1; and the crosslinking agent is a combination of peroxide and sulfur in a weight ratio of 1:1 to 1:

3.

2. The thermal jet silicone hose sheath material according to claim 1, characterized in that: It is made from the following ingredients in parts by weight: 95-105 parts natural raw rubber; 10-12 parts of the active system; Anti-aging system 8-10 parts; 60-72 parts of the reinforcement system; 10-12 parts of plasticizer system; Promote the system to 2.5-3 parts; Crosslinking agent 2-4 parts.

3. The thermal jet silicone hose sheath material according to claim 2, characterized in that: The thermal jet silicone hose sheath material is made from raw materials comprising the following parts by weight: 99 parts natural raw rubber; 12 portions of the active system; Nine anti-aging systems; 70-72 parts of the reinforcement system; 12 parts of plasticizer system; Promotion system 2.5 copies; Three parts of crosslinking agent.

4. The thermal jet silicone hose sheath material according to any one of claims 1-3, characterized in that: The natural raw rubber is a combination of No. 1 standard natural raw rubber and constant viscosity natural raw rubber in a weight ratio of 2:

1.

5. The thermal jet silicone hose sheath material according to any one of claims 1-3, characterized in that: The active system is a combination of zinc oxide and stearic acid in a weight ratio of 5:1; the anti-aging system is a combination of antioxidant 445, antioxidant 4010NA and protective paraffin 9108 in a weight ratio of 1:1.5:2; the plasticizing system is a combination of aromatic oil, adhesive RS and adhesive RA in a weight ratio of 4:1:

1.

6. The thermal jet silicone hose sheath material according to any one of claims 1-3, characterized in that: The reinforcing system is a combination of carbon black and white lubricating raw materials in a weight ratio of 4:1; the carbon black is a combination of medium-duty wear-resistant carbon black 220 and thermal cracking carbon black 990 in a weight ratio of 3:1; the white lubricating raw material is talc.

7. The thermal jet silicone hose sheath material according to any one of claims 1-3, characterized in that: The aforementioned accelerator system is a combination of accelerator DTDM and accelerator TT in a weight ratio of 4:1; the aforementioned crosslinking agent is a combination of peroxide and sulfur in a weight ratio of 1:2; the aforementioned peroxide is DCP or bis(2,5-diphenyltrioxide).

8. A method for preparing the thermal jet silicone hose sheath material according to claim 1, characterized in that: Includes the following steps: Step (1) Preparation of masterbatch through mixing: When the temperature of the internal mixer reaches 50℃~70℃, add natural raw rubber and plasticize for 240 seconds~360 seconds, add the anti-aging system and mix, raise the bolt once, add the reinforcing system and plasticizing system, raise the bolt twice, and wait for the temperature of the rubber compound to reach 115℃~125℃. Discharge the material from the mill, open the mill to produce sheets, cool with water to obtain masterbatch sheets, and let them stand for more than 12 hours. Step (2), two-stage mixing preparation of compounded rubber: When the temperature of the internal mixer reaches 50℃~70℃, add the masterbatch rubber sheet and plasticize for 300 seconds~360 seconds, add the active system for mixing, and lift the plug once. Add the accelerator system and crosslinking agent for mixing, and lift the plug twice. When the temperature of the rubber compound reaches 95℃~105℃, discharge the material from the internal mixer and put the rubber compound into the open mill. Turn the material over for 240 seconds~300 seconds, adjust the roller gap to 7~10mm, and the rubber compound is sheeted out. Cool it with water to obtain the silicone tube sheath compounded rubber material, and let it stand for more than 24 hours.

9. A thermal jet silicone hose sheath, characterized in that: It includes a braided layer, an inner rubber strip, and an outer rubber strip. The inner rubber strip is spirally supported inside the braided layer, and the outer rubber strip is spirally wound around the outside of the braided layer, with the outer rubber strip overlapping the inner rubber strip. Both the inner and outer rubber strips are made of the thermal jet silicone hose sheath material as described in claim 1.

10. A method for preparing the thermal jet silicone hose sheath according to claim 9, characterized in that: Includes the following steps: Step (1): Control the temperature of the extruder body to 70℃~80℃ and the temperature of the screw to 60℃~70℃. The silicone hose sheath compound rubber material is extruded and formed by the extruder to obtain a rubber strip. The rubber strip is wound on the mandrel once with a pitch of 60~80mm. Polyester or aramid yarn is used to braid the inner rubber strip to obtain a braided shape with a braiding angle of 25 degrees~45 degrees. Then, the rubber strip is wound a second time on the outside of the braided layer to form an outer rubber strip. The outer rubber strip overlaps with the inner rubber strip to obtain a sheath semi-finished product. The sheath semi-finished product is left to stand for more than 1 hour. Step (2): The sheath semi-finished product is vulcanized in a vulcanizing tank. The vulcanization conditions are: temperature 140℃~150℃, pressure 0.4~0.5MPa, time 110~120 minutes. Step (3): Remove the core rod to obtain the sheath product.

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