Self-lubricating fabric grey cloth and preparation method and application thereof, self-lubricating liner material and preparation method and application thereof, self-lubricating fabric composite material and preparation method and application thereof

Abstract

The invention relates to the technical field of self-lubricating materials, in particular to a self-lubricating fabric gray fabric and a preparation method and application thereof, a self-lubricating liner material and a preparation method and application thereof, and a self-lubricating fabric composite material and a preparation method and application thereof. The preparation method comprises the following steps: sequentially performing first twisting and first sizing on meta-aramid fibers to obtain pretreated meta-aramid fibers; sequentially performing second twisting and second sizing on polytetrafluoroethylene fibers to obtain pretreated polytetrafluoroethylene fibers; weaving the pre-treated meta-aramid fiber and the pre-treated polytetrafluoroethylene fiber to obtain a fabric gray fabric; sequentially performing dopamine-silane coupling agent modification on the gray fabric to obtain the self-lubricating gray fabric. Based on a fabric weaving pretreatment technology and a dopamine-silane coupling agent synergistic interface treatment technology, the prepared self-lubricating fabric grey cloth has excellent bonding strength, has excellent friction and wear properties in a working condition environment with a variable temperature range of-55-230 DEG C, and is long in service life.

Description

Technical Field

[0001] This invention relates to the field of self-lubricating materials technology, specifically to a self-lubricating fabric preform and its preparation method and application, a self-lubricating pad material and its preparation method and application, and a self-lubricating fabric composite material and its preparation method and application. Background Technology

[0002] Self-lubricating fabric composites are functional composite materials prepared by combining high-performance fiber woven fabrics as the skeleton material with resins and fillers. They possess low friction, wear resistance, and long service life. Self-lubricating fabric composites are commonly used in rotating, oscillating, and micro-motion mechanical parts in aerospace equipment, heavy engineering machinery, and marine equipment. The tribological properties of self-lubricating fabric composites have a significant impact on the operating status and stability of high-end equipment.

[0003] Currently, methods for improving the tribological properties of self-lubricating fabric composites mainly focus on fabric structure design, functional fillers, and resin matrix synthesis. For example, related technologies disclose an aramid III / PTFE self-lubricating fabric prefab and a self-lubricating pad composite material. The self-lubricating fabric prefab, designed with varying twill and satin weave structures using aramid III and PTFE as raw materials, adjusts the spatial distribution of fibers by adjusting the weave repeat number and weave dot count, thereby adjusting the tribological properties of the fabric and the self-lubricating pad material. However, the aforementioned pad material exhibits significant wear and a short service life in a variable temperature range of -55℃ to 230℃. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide a self-lubricating fabric greige, its preparation method and application, a self-lubricating pad material, its preparation method and application, and a self-lubricating fabric composite material, its preparation method and application. The self-lubricating fabric greige, self-lubricating pad material, and self-lubricating fabric composite material provided by this invention exhibit excellent tribological properties and long service life under varying temperature conditions from -55℃ to 230℃.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for preparing a self-lubricating fabric greige, comprising the following steps: Meta-aramid fibers are subjected to a first twist and a first sizing process in sequence to obtain pretreated meta-aramid fibers. The polytetrafluoroethylene fibers were subjected to a second twist and a second sizing in sequence to obtain pretreated polytetrafluoroethylene fibers. The pretreated meta-aramid fibers and pretreated polytetrafluoroethylene fibers are woven together to obtain a fabric greige. The fabric greige is modified sequentially with dopamine-silane coupling agent to obtain a self-lubricating fabric greige.

[0006] Preferably, the breaking strength of the meta-aramid is ≥4cN / dtex; The tensile strength of the polytetrafluoroethylene fiber is ≥1.2 cN / dtex; The twist of the first twist and the second twist are independently 40~280 twists / meter; The sizing agents used for the first and second sizing processes independently comprise: 2-16% modified polyester sizing agent, 2-16% polyvinyl alcohol, 0.01-0.1% defoamer, 0.01-0.1% antistatic agent, and the balance being water; The modified polyester slurry has a solid content of 27-33 wt%; the modified polyester in the modified polyester slurry includes polyester resin; The fabric structure includes: a weave repeat number of 2 to 6, a total tightness of 89 to 99.5, a warp tightness of 65 to 94, and a weft tightness of 70 to 83. The mass fraction of aramid in the intermediate position of the fabric is 32-87%; The warp strength of the fabric is ≥1040N and the weft strength is ≥810N.

[0007] Preferably, the dopamine-silane coupling agent modification includes: immersing the fabric in a dopamine aqueous solution for dopamine modification, and then immersing it in a silane coupling agent solution for silane coupling agent modification. The concentration of the dopamine aqueous solution is 0.01~0.05 mol / L, and the pH value is 8~8.5; the dopamine modification time is 2~10 h; The concentration of the silane coupling agent in the silane coupling agent solution is 2-8 wt%, and the solvent in the silane coupling agent solution includes lower alcohols and water; the silane coupling agent includes one or more of KH550, KH560 and KH570; the modification time of the silane coupling agent is 1-3 h.

[0008] The present invention also provides a self-lubricating fabric greige prepared by the preparation method described in the above technical solution.

[0009] Preferably, the self-lubricating fabric has a unit area mass of 160~300g / m². 2 .

[0010] The present invention also provides a self-lubricating pad material, comprising the self-lubricating fabric described in the above technical solution and a resin loaded in the self-lubricating fabric.

[0011] The present invention also provides a method for preparing the self-lubricating gasket material described in the above technical solution, comprising the following steps: Impregnate the self-lubricating fabric with resin to obtain the resin-impregnated fabric; The impregnated fabric is cured to obtain a self-lubricating fabric composite material.

[0012] The present invention also provides a self-lubricating fabric composite material, comprising a metal matrix and a self-lubricating pad material located on the surface of the matrix; the self-lubricating pad material is the self-lubricating pad material described in the above technical solution or the self-lubricating pad material prepared by the preparation method described in the above technical solution.

[0013] The present invention also provides a method for preparing the self-lubricating fabric composite material described in the above technical solution, comprising the following steps: Impregnate the self-lubricating fabric with resin to obtain the resin-impregnated fabric; The impregnated fabric is pre-cured to obtain a pre-cured material; The pre-cured material is adhered to the surface of a metal substrate and cured to obtain a self-lubricating fabric composite material.

[0014] The present invention also provides the application of the self-lubricating fabric preform described in the above technical solution, the self-lubricating pad material described in the above technical solution, the self-lubricating pad material prepared by the preparation method described in the above technical solution, the self-lubricating fabric composite material described in the above technical solution, or the self-lubricating fabric composite material prepared by the preparation method described in the above technical solution in friction motion mechanisms.

[0015] This invention uses meta-aramid fiber and polytetrafluoroethylene fiber as raw materials to prepare a self-lubricating fabric. By performing pre-weaving processing (twisting and sizing) on ​​the raw materials, the meta-aramid fiber and polytetrafluoroethylene fiber are endowed with better strength and abrasion resistance. The pre-treated fibers are then woven to obtain the fabric. This invention significantly improves the interfacial bonding force between the fiber and resin and the surface activity of the fabric by performing joint interfacial modification with silane coupling agent and dopamine on the surface of the fabric. The self-lubricating fabric provided by this invention has excellent adhesive strength and excellent tribological properties in a variable temperature range of -55~230℃, with a long service life. It can be used for mechanical moving parts, especially in variable temperature environments of -55℃ to 230℃.

[0016] The self-lubricating fabric prefabricated by this invention, after subsequent resin impregnation and curing, yields a self-lubricating pad material and a self-lubricating fabric composite material containing a metal matrix. These materials exhibit excellent friction and wear performance in a variable temperature range of -55 to 230°C, have a long service life, and can be used for mechanical moving parts, especially in a variable temperature range of -55°C to 230°C.

[0017] The results of the examples show that the self-lubricating fabric composite material provided by the present invention, after continuous testing under a load of 60 MPa, 2000 oscillations at a low temperature of -55℃, 14000 oscillations at room temperature, and 4000 oscillations at a high temperature of 230℃, exhibits a wear amount as low as 30 μm, which is only 5% of the material thickness. Moreover, it maintains a low coefficient of friction throughout the test period. This indicates that the self-lubricating fabric composite material provided by the present invention has excellent wear resistance, temperature resistance, and a low coefficient of friction under varying temperature conditions from -55℃ to 230℃. Detailed Implementation

[0018] This invention provides a method for preparing a self-lubricating fabric greige, comprising the following steps: Meta-aramid fibers are subjected to a first twist and a first sizing process in sequence to obtain pretreated meta-aramid fibers. The polytetrafluoroethylene fibers were subjected to a second twist and a second sizing in sequence to obtain pretreated polytetrafluoroethylene fibers. The pretreated meta-aramid fibers and pretreated polytetrafluoroethylene fibers are woven together to obtain a fabric greige. The fabric greige is modified sequentially with dopamine-silane coupling agent to obtain a self-lubricating fabric greige.

[0019] Unless otherwise specified, the materials and equipment used in this invention are all commercially available products in the field.

[0020] The present invention involves sequentially performing a first twisting and a first sizing on meta-aramid fibers to obtain pretreated meta-aramid fibers.

[0021] In this invention, the meta-aramid fibers undergo performance testing before use to screen out those with sufficient breaking strength. The breaking strength of the meta-aramid fibers can be ≥4 cN / dtex, or it can be 4~4.8 cN / dtex, specifically 4 cN / dtex, 4.1 cN / dtex, 4.2 cN / dtex, 4.3 cN / dtex, 4.4 cN / dtex, 4.5 cN / dtex, 4.6 cN / dtex, 4.7 cN / dtex or 4.8 cN / dtex.

[0022] In this invention, the first twisting can be performed by sequentially guiding meta-aramid fibers through the yarn guide channel of a twisting machine, setting the twist, and then twisting. In this invention, the conditions for the first twisting can include: the twist (S-twist) can be 40~280 twists / meter (S / m), or 80~150 S / m, specifically 40S / m, 50S / m, 60S / m, 70S / m, 80S / m, 90S / m, 100S / m, 110S / m, 120S / m, 130S / m, 140S / m, 150S / m, 160S / m, 170S / m, 180S / m, 190S / m, 200S / m, 210S / m, 220S / m, 230S / m. m, 240S / m, 250S / m, 260S / m, 270S / m or 280S / m; twist direction is S; speed is 400~6000r / min, or 400~1000r / min, specifically 400r / min, 500r / min, 600r / min, 700r / min, 800r / min, 900r / min, 1000r / min, 2000r / min, 3000r / min, 4000r / min, 5000r / min or 6000r / min.

[0023] In this invention, the composition of the sizing agent used for the first sizing may include: 2-16% modified polyester sizing agent, or 4-8%, specifically 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, or 16%; 3-16% polyvinyl alcohol (PVA), or 8-12%, specifically 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, or 16%; and defoamer. The content of the sizing agent is 0.01~0.1%, or 0.01~0.05%, specifically 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.1%; the antistatic agent is 0.01~0.1%, or 0.01~0.05%, specifically 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.1%; the balance is water. In this invention, the solid content of the sizing agent can be 5~18wt%, or 14~16wt%, specifically 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, or 18wt%. In this invention, the solid content of the modified polyester sizing agent can be 27-33 wt%, or 28-32 wt%, specifically 30%; the modified polyester in the modified polyester sizing agent includes polyester resin; the solvent in the modified polyester sizing agent can include water. In this invention, the degree of polymerization of the polyvinyl alcohol can be 1700-1800, or 1750; the polyvinyl alcohol can be PVA1799. In this invention, the defoamer can include polyether-modified silicone defoamer, specifically block polyether-modified silicone and / or side-chain comb-shaped modified silicone defoamer. In this invention, the antistatic agent can include nonionic antistatic agent, specifically polyethylene glycol ester. The sizing agent used in this invention is mainly modified polyester sizing agent and polyvinyl alcohol, with defoamer and antistatic agent as auxiliary agents. It has good compatibility with aramid fibers, improves fiber bundle properties, abrasion resistance and weaveability, and reduces fabric defect rate.

[0024] In this invention, the preparation method of the sizing agent may include the following steps: heating water and then adding modified polyester sizing agent, polyvinyl alcohol, defoamer, and antistatic agent, and mixing them. In this invention, the heating temperature can be 90~100℃, or it can be 95℃.

[0025] In this invention, the conditions for the first sizing may include: a sizing tank temperature of 50~65℃, or 55~60℃; a sizing speed of 100~300m / min, or 150~250m / min, or 200m / min; a pre-drying temperature of 70~85℃, or 75~80℃; and a drying temperature of 85~95℃, or 90℃.

[0026] The present invention involves subjecting polytetrafluoroethylene fibers to a second twist and a second sizing process to obtain pretreated polytetrafluoroethylene fibers.

[0027] In this invention, the polytetrafluoroethylene (PTFE) fibers undergo performance testing before use to select those with sufficient breaking strength. The breaking strength of the PTFE fibers can be ≥1.2 cN / dtex, or it can be 1.2~1.8 cN / dtex, specifically 1.2 cN / dtex, 1.3 cN / dtex, 1.4 cN / dtex, 1.5 cN / dtex, 1.6 cN / dtex, 1.7 cN / dtex, or 1.8 cN / dtex.

[0028] In this invention, the conditions for the second twisting and the second sizing are the same as those for the first twisting and the first sizing, and will not be repeated here.

[0029] After obtaining pretreated meta-aramid fibers and pretreated polytetrafluoroethylene fibers, the present invention weaves the pretreated meta-aramid fibers and pretreated polytetrafluoroethylene fibers to obtain a fabric greige.

[0030] In this invention, the fabric structure may include: a weave repeat number (R) of 2-6, or 3-5, specifically 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, or 6; a total tightness (E) of 89-99.5, or 95-99, specifically 89, 90, 91, 92, 93, 94, 95, 96, 96.7, 97, 98, 99, or 99.5; and a warp tightness (E...). j The value is 65~94, and can also be 85~94, specifically 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93 or 94; latitudinal compactness (E w The value is 70~83, and can also be 72~83, specifically 70, 71, 72, 72.7, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82 or 83. In this invention, the weaving is carried out on a loom. This invention does not have any special limitations on the weaving, as long as the fabric with the above-mentioned structure can be obtained.

[0031] In this invention, the mass fraction of aramid in the middle position of the fabric can be 32-87%, or 50-70%, specifically 32%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 87%.

[0032] In this invention, the warp strength of the fabric can be ≥1040N, or 1040~1340N; the weft strength of the fabric can be ≥810N, or 810~1060N; and the area mass of the fabric can be 160~300g / m². 2 Specifically, it can be 160g / m 2 180g / m 2 200g / m 2 220g / m 2 240g / m 2 250g / m 2 260g / m 2 280g / m 2 295g / m 2 Or 300g / m 2 .

[0033] After obtaining the fabric greige, the present invention modifies the fabric greige sequentially with dopamine-silane coupling agent to obtain a self-lubricating fabric greige.

[0034] In this invention, the modification of the dopamine-silane coupling agent may further include: desizing the fabric. In this invention, the pH value of the desizing agent used for the desizing treatment can be 8-10, or 8.5-9.5, or even 9; the desizing agent may include an aqueous sodium hydroxide solution. In this invention, the temperature of the desizing treatment is 80-95℃, or 85-90℃; the time of the desizing treatment can be 0.5-2 hours, or 1-1.5 hours.

[0035] In this invention, the dopamine-silane coupling agent modification includes: immersing the fabric in a dopamine aqueous solution for dopamine modification, and then immersing it in a silane coupling agent solution for silane coupling agent modification.

[0036] In this invention, the concentration of the dopamine aqueous solution can be 0.01~0.05 mol / L, or 0.01~0.02 mol / L, specifically 0.01 mol / L, 0.02 mol / L, 0.03 mol / L, 0.04 mol / L, or 0.05 mol / L; the pH value of the dopamine aqueous solution can be 8.5; the pH adjuster for the dopamine aqueous solution can include hydrochloric acid. In this invention, the mass-to-volume ratio of the fabric to the dopamine aqueous solution can be 1 g: 10~20 mL, or 1 g: 12~18 mL, further 1 g: 14~16 mL, specifically 1 g: 15 mL.

[0037] In this invention, the dopamine modification temperature can be room temperature (18~35℃); the dopamine modification time can be 2~10h, or 4~6h, specifically 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h or 10h.

[0038] After dopamine modification, the present invention can further dry the dopamine-modified wet fabric to obtain a dopamine-modified fabric. In the present invention, the drying temperature can be 60~80℃, or 70~80℃, specifically 60℃, 65℃, 70℃, 75℃ or 80℃; the present invention does not have a special limitation on the drying time, as long as it is dried to constant weight.

[0039] In this invention, the concentration of the silane coupling agent in the silane coupling agent solution can be 2-8 wt%, or 2-4 wt%, specifically 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, or 8 wt%. The solvent in the silane coupling agent solution can include a lower alcohol and water, and the lower alcohol can include ethanol. The volume ratio of the lower alcohol to water can be 1:3-7, or 1:4-6, or even 1:5. The silane coupling agent can include one or more of KH550, KH560, and KH570. In this invention, the mass-to-volume ratio of the fabric greige to the silane coupling agent solution can be 1 g:10-20 mL, or 1 g:12-18 mL, or even 1 g:14-16 mL, specifically 1 g:15 mL.

[0040] In this invention, the temperature for modifying the silane coupling agent can be room temperature (18~25℃); the modification time for the silane coupling agent can be 1~3h, or 1~2h, specifically 1h, 1.5h, 2h, 2.5h or 3h.

[0041] After modification with the silane coupling agent, the present invention can further dry the self-lubricating wet fabric obtained by the silane coupling agent modification to obtain a self-lubricating fabric. In the present invention, the drying temperature can be 80~120℃, or 80~10℃, specifically 80℃, 90℃, 100℃, 110℃ or 120℃; the present invention does not have a special limitation on the drying time, drying to constant weight is sufficient.

[0042] This invention also provides a self-lubricating fabric greige prepared by the method described above. In this invention, the weight per square meter of the self-lubricating fabric greige is 160~300 g / m². 2 Specifically, it can be 160g / m 2 180g / m 2 200g / m 2 220g / m 2 240g / m 2 250g / m 2 260g / m 2 280g / m 2 295g / m 2 Or 300g / m 2 .

[0043] This invention improves the performance of meta-aramid fibers and polytetrafluoroethylene fibers based on pre-weaving treatment technology (twisting and sizing) and synergistic interface treatment technology with dopamine-silane coupling agent. It enhances the mechanical properties and cohesion of the fibers, increases the surface activity of the fabric and the interfacial bonding strength with the resin, and regulates the spatial distribution of meta-aramid fibers and polytetrafluoroethylene fibers through the microstructure. This endows the self-lubricating fabric with superior resistance to temperature ranges from -55 to 230°C and tribological properties, significantly improving its service life.

[0044] The present invention also provides a self-lubricating pad material, comprising the self-lubricating fabric described in the above technical solution and a resin loaded in the self-lubricating fabric. In the present invention, the mass fraction of the self-lubricating fabric in the self-lubricating pad material can be 15-38%, or 18-20%, specifically 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, or 38%.

[0045] The present invention also provides a method for preparing the self-lubricating pad material described in the above technical solution, comprising the following steps: impregnating a self-lubricating fabric blank with resin to obtain an impregnated fabric; and curing the impregnated fabric to obtain a self-lubricating fabric composite material.

[0046] In this invention, the resin may include one or more of phenolic resin, epoxy resin, polyimide resin, and urea-formaldehyde resin. In this invention, the impregnation process may include: immersing a self-lubricating fabric in the resin, and then removing excess resin by squeezing with a rubber roller. In this invention, the impregnation may be performed 1 to 4 times, or even 2 to 3 times. The impregnation method used in this invention is simple and quick to operate.

[0047] In this invention, the mass fraction of resin in the impregnated fabric can be 5-35%, 10-30%, or 15-25%, specifically 5%, 10%, 15%, 16%, 20%, 23%, 25%, 30%, or 35%.

[0048] In this invention, the curing process includes sequentially performing a first curing and a second curing. In this invention, the temperature of the first curing can be 40~110℃, or 60~100℃, specifically 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, or 110℃; the pressure of the first curing can be 0.1~3.5MPa, or 0.5~1MPa, specifically 0.1MPa, 0.3MPa, 0.5MPa, 0.8MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, or 3.5MPa; the time of the first curing can be 0.5~2h, or 1~2h, specifically 0.5h, 1h, 1.5h, or 2h. In this invention, the second curing temperature can be 80~220℃, or 120~160℃, specifically 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, or 220℃; the second curing pressure can be 0.4~4.5MPa, or 0.5~1MPa, specifically 0.4MPa, 0.5MPa, 0.8MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, or 4.5MPa; the second curing time can be 1~4.5h, or 2~3h, specifically 1h, 1.5h, 110min, 2h, 2.5h, 3h, 3.5h, 4h, or 4.5h.

[0049] The present invention also provides a self-lubricating fabric composite material, comprising a metal matrix and a self-lubricating pad material located on the surface of the matrix; the self-lubricating pad material is the self-lubricating pad material described in the above technical solution or the self-lubricating pad material prepared by the preparation method described in the above technical solution.

[0050] In this invention, the metal matrix may include metal materials for spherical bearings, specifically including 45# steel, 7075 aluminum alloy or TC4 titanium alloy.

[0051] This invention also provides a method for preparing the self-lubricating fabric composite material described in the above technical solution, comprising the following steps: impregnating a self-lubricating fabric prefabricated fabric with resin to obtain an impregnated fabric; pre-curing the impregnated fabric to obtain a pre-cured material; and bonding the pre-cured material to the surface of a metal substrate and curing it (referred to as the third curing) to obtain the self-lubricating fabric composite material. In this invention, the method for preparing the impregnated fabric is the same as the method for preparing the impregnated fabric in the aforementioned self-lubricating pad material preparation process; the pre-curing conditions are the same as the aforementioned first curing conditions, and the third curing conditions are the same as the aforementioned second curing conditions, which will not be repeated here.

[0052] This invention also provides the application of the self-lubricating fabric preform, the self-lubricating pad material, the self-lubricating pad material prepared by the preparation method described in the above-mentioned technical solutions, the self-lubricating fabric composite material, or the self-lubricating fabric composite material prepared by the preparation method described in the above-mentioned technical solutions in friction motion mechanisms. In this invention, the friction motion mechanism may include a spherical bearing, an aircraft tail fin, or an aileron. The self-lubricating fabric preform, the self-lubricating pad material, and the self-lubricating fabric composite material provided by this invention exhibit excellent tribological properties and long service life under varying temperature conditions from -55℃ to 230℃, and have promising application prospects in friction motion mechanisms.

[0053] To further illustrate the present invention, the following detailed descriptions, in conjunction with embodiments, illustrate the self-lubricating fabric greige fabric and its preparation method and application, the self-lubricating pad material and its preparation method and application, and the self-lubricating fabric composite material and its preparation method and application. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0054] In the following examples and comparative examples, the mechanical properties of meta-aramid and polytetrafluoroethylene fibers were tested using a yarn strength tester. The breaking strength of meta-aramid was 4.5 cN / dtex, and the breaking strength of polytetrafluoroethylene was 1.35 cN / dtex. PVA was PVA1799. The nonionic antistatic agent was polyethylene glycol. WISESTER ARF modified polyester sizing agent (30 wt% solids content) was purchased from Bozzetto Group. The epoxy resin was AF-4020A epoxy resin. The phenolic resin was phenolic resin 204. The polyether-modified silicone defoamer was DiLi-828.

[0055] Tribological property testing conditions from low temperature to room temperature to high temperature: load 60MPa, frequency oscillation 0.2Hz, 2000 oscillations at low temperature -55℃, 14000 oscillations at room temperature, and 4000 oscillations at high temperature 230℃. Then the wear of the composite material is tested. During the heating process, the testing machine is stopped, but the composite material does not detach from the friction surface.

[0056] Example 1 (1) Pre-weaving process treatment Meta-aramid fibers were twisted at 400 r / min and a twist of 145 S / m before sizing to obtain pretreated meta-aramid fibers. The sizing conditions were as follows: sizing speed 200 m / min, sizing bath temperature 60℃, pre-drying temperature 70℃, and drying temperature 85℃.

[0057] Polytetrafluoroethylene (PTFE) fibers were twisted at 600 r / min and a twist of 145 S / m before sizing to obtain pretreated PTFE fibers. The sizing conditions were as follows: sizing speed 300 m / min, sizing bath temperature 60℃, pre-drying temperature 80℃, and drying temperature 90℃.

[0058] The sizing agents for meta-aramid and polytetrafluoroethylene fibers, by mass percentage, consist of: 5% modified polyester sizing agent, 10% PVA, 0.02% nonionic antistatic agent, 0.02% polyether-modified silicone defoamer, and the balance being water.

[0059] (2) Weave according to the established organizational structure Pretreated meta-aramid and pretreated polytetrafluoroethylene fibers were woven using a fabric weave structure with a weave cycle number R=3 to obtain a greige fabric. The total tightness of the greige fabric was 99, and the warp tightness was E. j The latitudinal compactness is 94, and the latitudinal tightness is E. W The value is 83, and the mass per unit area is 295 g / m². 2 The mass content of aramid in the middle of the fabric is 49%.

[0060] (3) Surface treatment to obtain self-lubricating fabric greige. The fabric was desized in a sodium hydroxide aqueous solution with pH=8~10 and 80~95℃ for 60 min, then modified by immersing in a 0.02mol / L dopamine aqueous solution (pH=8.5) for 4 h, dried at 80℃, and then modified by immersing in a 2wt% KH550-ethanol-water mixed solution (ethanol:water volume ratio=1:4) for 1 h, and dried at 90℃ to obtain a self-lubricating fabric.

[0061] (4) Preparation of self-lubricating fabric composites The self-lubricating fabric was impregnated with epoxy resin, and excess epoxy resin was removed by extrusion using a rubber roller. This step was repeated three times until the epoxy resin content in the composite material reached 23% by mass. The mixture was then heat-treated at 80℃ and 0.5MPa for 2 hours to obtain a pre-cured material. This pre-cured material was bonded to a 7075 aluminum alloy surface and cured at 120℃ and 0.5MPa for 120 minutes to obtain the self-lubricating fabric composite material. The average peel strength of the self-lubricating fabric composite material was 1.7 N / mm. After low-temperature-room-high-temperature tribological performance testing, the average wear of the composite material was 30 μm, accounting for 5.8% of the composite material thickness, and the average coefficient of friction was 0.15.

[0062] Example 2 (1) Pre-weaving process treatment Meta-aramid fibers were twisted at 600 r / min and a twist of 80 S / m before sizing to obtain pretreated meta-aramid fibers. The sizing conditions were as follows: sizing speed 200 m / min, sizing bath temperature 60℃, pre-drying temperature 85℃, and drying temperature 95℃.

[0063] Polytetrafluoroethylene (PTFE) fibers were twisted at 800 r / min and a twist of 80 S / m before sizing to obtain pretreated PTFE fibers. The sizing conditions were as follows: sizing speed 400 m / min, sizing bath temperature 60℃, pre-drying temperature 85℃, and drying temperature 95℃.

[0064] By mass percentage, the sizing agents for meta-aramid and polytetrafluoroethylene fibers are: 8% modified polyester sizing agent, 7% PVA, 0.01% nonionic antistatic agent, 0.01% polyether modified silicone defoamer, and the balance being water.

[0065] (2) Weave according to the established organizational structure Pretreated meta-aramid and pretreated polytetrafluoroethylene fibers were woven using a fabric weave structure with a weave cycle number R=4 to obtain a greige fabric. The total tightness of the greige fabric was 96.7, and the warp tightness was E. j The latitudinal compactness is 89, E. W The value is 72.7, and the mass per unit area is 260 g / m². 2 The mass content of aramid in the middle of the fabric is 42%.

[0066] (3) Dopamine-silane coupling agent treatment on fabric surface The fabric was desized in a sodium hydroxide aqueous solution with pH=8~10 and 80~95℃ for 60 min, modified by immersion in a 0.01mol / L dopamine aqueous solution (pH=8.5) for 6 h, dried at 80℃, modified by immersion in a 4wt% KH550-ethanol-water mixed solution (ethanol:water volume ratio=1:6) for 2 h, and dried at 90℃ to obtain a self-lubricating fabric.

[0067] (4) Preparation of self-lubricating fabric composites The self-lubricating fabric was impregnated with phenolic resin, and excess phenolic resin was removed by squeezing with a rubber roller. This step was repeated twice until the mass percentage of phenolic resin in the composite material was 16%. The mixture was then heat-treated at 80℃ and 0.5MPa for 1 hour to obtain a pre-cured material. The pre-cured material was bonded to a 45# steel surface and cured at 160℃ and 0.9MPa for 110 minutes to obtain the self-lubricating fabric composite material. The average peel strength of the self-lubricating fabric composite material was 1.8 N / mm. After low-temperature-room-high-temperature tribological performance testing, the average wear of the composite material was only 45 μm, accounting for 11% of the composite material thickness, and the average coefficient of friction was 0.18.

[0068] Comparative Example 1 The only difference from Example 1 is that step (1) is omitted, and in step (2), the dopamine modification and silane coupling agent modification are replaced by cleaning the oil on the fiber surface with anhydrous ethanol. The specific steps are as follows: Meta-aramid and polytetrafluoroethylene fibers were woven using a weave structure with a weave count R=3 to obtain a greige fabric. The total tightness of the greige fabric was 99, and the warp tightness was E. j The latitudinal compactness is 94, and the latitudinal tightness is E. W The value is 83, and the mass per unit area is 295 g / m². 2 The aramid content in the intermediate position of the fabric was 39%. The fabric was desized using a sodium hydroxide aqueous solution with pH 8-10 and a temperature of 80-95℃. The oil on the fabric surface was removed using anhydrous ethanol, and the fabric was dried at 90℃ to obtain a self-lubricating fabric. The self-lubricating fabric was then impregnated with epoxy resin, and excess epoxy resin was removed by pressing with a rubber roller. This process was repeated three times until the epoxy resin content in the composite material reached 23% by mass. The mixture was then heat-treated at 80℃ and 0.5 MPa for 2 hours to obtain a pre-cured material. This pre-cured material was bonded to a 7075 aluminum alloy surface and cured at 120℃ and 0.5 MPa for 120 minutes to obtain the self-lubricating fabric composite material. The average peel strength of the self-lubricating fabric composite material was 1.0 N / mm. After low-temperature-room-high-temperature tribological performance testing, the average wear of the composite material was 110 μm, accounting for 21.3% of the composite material thickness, and the average coefficient of friction was 0.19.

[0069] Comparing Example 1 and Comparative Example 1, it is evident that the self-lubricating pad material prepared without pre-weaving treatment and dopamine-silane coupling agent treatment on the fabric surface exhibits significantly lower peel strength and tribological properties compared to the self-lubricating pad material prepared in Example 1 under the same test conditions. This indicates that the self-lubricating fabric prepared according to the present invention possesses superior interfacial bonding performance and tribological properties.

[0070] Comparative Example 2 Aramid III fiber was used as the warp yarn and PTFE fiber as the weft yarn, woven in a varied satin weave with 8 repeats, 3 warp flybacks, and 5 weft flybacks. The aramid III fiber fabric was not subjected to the treatment described in this patent. A self-lubricating liner material was prepared using phenolic resin via an impregnation method. The liner was then bonded to a 45# steel surface to obtain a self-lubricating fabric composite material. The average peel strength of the self-lubricating fabric composite material was 1.2 N / mm. After low-temperature-room-high-temperature tribological performance testing, the average wear of the composite material was 75 μm, accounting for 15% of the composite material thickness, and the average coefficient of friction was 0.21.

[0071] Compared to self-lubricating pad materials prepared using aramid III / PTFE fiber-woven satin weave fabrics, the self-lubricating fabric prepared in this invention has better interfacial bonding performance and tribological properties.

[0072] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a self-lubricating fabric, characterized in that, Includes the following steps: Meta-aramid fibers are subjected to a first twist and a first sizing process in sequence to obtain pretreated meta-aramid fibers. The polytetrafluoroethylene fibers were subjected to a second twist and a second sizing in sequence to obtain pretreated polytetrafluoroethylene fibers. The pretreated meta-aramid fibers and pretreated polytetrafluoroethylene fibers are woven together to obtain a fabric greige. The fabric greige is modified sequentially with dopamine-silane coupling agent to obtain a self-lubricating fabric greige.

2. The preparation method according to claim 1, characterized in that, The breaking strength of the meta-aramid is ≥4cN / dtex; The tensile strength of the polytetrafluoroethylene fiber is ≥1.2 cN / dtex; The twist of the first twist and the second twist are independently 40~280 twists / meter; The sizing agents used for the first and second sizing processes independently comprise: 2-16% modified polyester sizing agent, 2-16% polyvinyl alcohol, 0.01-0.1% defoamer, 0.01-0.1% antistatic agent, and the balance being water; The modified polyester slurry has a solid content of 27-33 wt%; the modified polyester in the modified polyester slurry includes polyester resin; The fabric structure includes: a weave repeat number of 2 to 6, a total tightness of 89 to 99.5, a warp tightness of 65 to 94, and a weft tightness of 70 to 83. The mass fraction of aramid in the intermediate position of the fabric is 32-87%; The warp strength of the fabric is ≥1040N and the weft strength is ≥810N.

3. The preparation method according to claim 1, characterized in that, The dopamine-silane coupling agent modification includes: immersing the fabric in a dopamine aqueous solution for dopamine modification, and then immersing it in a silane coupling agent solution for silane coupling agent modification. The concentration of the dopamine aqueous solution is 0.01~0.05 mol / L; the dopamine modification time is 2~10 h; The concentration of the silane coupling agent in the silane coupling agent solution is 2-8 wt%, and the solvent in the silane coupling agent solution includes lower alcohols and water; the silane coupling agent includes one or more of KH550, KH560 and KH570; the modification time of the silane coupling agent is 1-3 h.

4. The self-lubricating fabric greige obtained by the preparation method according to any one of claims 1 to 3.

5. The self-lubricating fabric according to claim 4, characterized in that, The self-lubricating fabric has a unit area mass of 160~300g / m². 2 .

6. A self-lubricating gasket material, characterized in that, It includes the self-lubricating fabric as described in claim 5 or 6 and the resin loaded in the self-lubricating fabric.

7. The method for preparing the self-lubricating pad material according to claim 6 comprises the following steps: Impregnate the self-lubricating fabric with resin to obtain the resin-impregnated fabric; The impregnated fabric is cured to obtain a self-lubricating fabric composite material.

8. A self-lubricating fabric composite material, characterized in that, It includes a metal substrate and a self-lubricating pad material located on the surface of the substrate; the self-lubricating pad material is the self-lubricating pad material according to claim 6 or the self-lubricating pad material prepared by the preparation method according to claim 7.

9. The method for preparing the self-lubricating fabric composite material according to claim 8, characterized in that, Includes the following steps: Impregnate the self-lubricating fabric with resin to obtain the resin-impregnated fabric; The impregnated fabric is pre-cured to obtain a pre-cured material; The pre-cured material is adhered to the surface of a metal substrate and cured to obtain a self-lubricating fabric composite material.

10. The application of the self-lubricating fabric greige of claim 4 or 5, the self-lubricating pad material of claim 6, the self-lubricating pad material prepared by the preparation method of claim 7, the self-lubricating fabric composite material of claim 8, or the self-lubricating fabric composite material prepared by the preparation method of claim 9 in a friction motion mechanism.