CN119039642B - A wear-resistant drag chain protective material and its preparation method and application - Google Patents
A wear-resistant drag chain protective material and its preparation method and application Download PDFInfo
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- CN119039642B CN119039642B CN202411355574.0A CN202411355574A CN119039642B CN 119039642 B CN119039642 B CN 119039642B CN 202411355574 A CN202411355574 A CN 202411355574A CN 119039642 B CN119039642 B CN 119039642B
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/04—Coating
- C08J7/042—Coating with two or more layers, where at least one layer of a composition contains a polymer binder
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B7/00—Insulated conductors or cables characterised by their form
- H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
- H01B7/18—Protection against damage caused by wear, mechanical force or pressure; Sheaths; Armouring
- H01B7/1835—Sheaths comprising abrasive charges
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2327/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
- C08J2327/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
- C08J2327/12—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
- C08J2327/18—Homopolymers or copolymers of tetrafluoroethylene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2427/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
- C08J2427/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
- C08J2427/12—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
- C08J2427/18—Homopolymers or copolymers of tetrafluoroethylene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2471/00—Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/14—Extreme weather resilient electric power supply systems, e.g. strengthening power lines or underground power cables
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- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
Abstract
The invention discloses a wear-resistant drag chain protection material, a preparation method and application thereof, and belongs to the technical field of cable materials. The wear-resistant drag chain protection material is prepared by mixing polytetrafluoroethylene dispersion resin and a booster agent, then carrying out extrusion molding, calendaring treatment, removing the booster agent, then carrying out stretching treatment to obtain a stretched film, winding the stretched film on a hard piece, carrying out first pressing, first sintering shaping, second pressing and second sintering shaping to obtain a second shaping material, coating a tetrafluoro emulsion on the outer surface of the second shaping material, curing, and coating a perfluoropolyether lubricating oil on the inner surface of the second shaping material. The method is simple and easy to operate, the friction coefficient between the drag chain and the protection device can be effectively reduced, and the obtained wear-resistant drag chain protection material has high density, good flexibility, smooth surface, wear resistance and high wear resistance.
Description
Technical Field
The invention relates to the technical field of cable materials, in particular to a wear-resistant drag chain protection material and a preparation method and application thereof.
Background
The existing dust-free cable drag chain protection structure is made of polymer Polyurethane (PU) and expanded polytetrafluoroethylene products (e-EPTFE) in a compounding mode. However, the dust-free cable drag chain protection structure prepared by compounding polyurethane and expanded polytetrafluoroethylene products can carry out long-time dry friction with the cable body inside the dust-free cable drag chain protection structure in the application process, and friction can only be protected through the self wear resistance of the e-EPTFE material, so that the dust-free cable drag chain protection structure has limited wear resistance and short service life.
In view of this, the present invention has been made.
Disclosure of Invention
The invention aims to provide a wear-resistant drag chain protection material, and a preparation method and application thereof, so as to solve or improve the technical problems.
The invention can be realized as follows:
The invention provides a preparation method of a wear-resistant drag chain protection material, which comprises the following steps of mixing polytetrafluoroethylene dispersion resin with a booster, performing extrusion molding to obtain an extrusion baseband, performing calendaring treatment on the extrusion baseband to obtain a calendaring belt, removing the booster in the calendaring belt, performing stretching treatment to obtain a stretched film, winding the stretched film on a hard piece, performing first pressing and then performing first sintering shaping to obtain a first shaping material, performing second pressing and then performing second sintering shaping to obtain a second shaping material, coating a tetrafluoro emulsion on the outer surface of the second shaping material, curing, and coating perfluoropolyether lubricating oil on the inner surface of the second shaping material;
the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is 4:1 to 6:1;
The pressure of the first pressing is 0.2-1 MPa, and the time of the first pressing is 1-2 min;
The temperature of the primary sintering setting is 350-380 ℃, and the time of the primary sintering setting is 15-30 min;
the pressure of the second pressing is 0.5-1.5 MPa, and the time of the second pressing is 2 min-3 min;
In an alternative embodiment, the temperature of the second sintering and shaping is 350-380 ℃, and the time of the second sintering and shaping is 15-30 min;
The solid content of the tetrafluoro emulsion is 45% -65%, and the coating amount of the tetrafluoro emulsion is 250mL/m 2~350mL/m2;
The coating amount of the perfluoropolyether lubricating oil was 150mL/m 2~250mL/m2.
In an alternative embodiment, the booster comprises at least one of an alkane solvent, kerosene, petroleum ether, and paraffin wax.
In an alternative embodiment, the extrusion molding pressure is 30bar to 40bar.
In an alternative embodiment, the thickness of the calendered tape is 0.5mm to 0.7mm.
In an alternative embodiment, the stretching treatment includes transverse stretching and longitudinal stretching;
Wherein the stretching multiple of the transverse stretching is 8-10 times, and the transverse stretching is carried out under the condition of 250-280 ℃;
The stretching multiple of the longitudinal stretching is 12-16 times, and the longitudinal stretching is performed under the condition of 320-400 ℃.
In an alternative embodiment, the curing temperature is 220 ℃ to 245 ℃ and the curing time is 15min to 30min.
In an alternative embodiment, the molecular weight of the perfluoropolyether lubricating oil is 10000g/mol to 15000g/mol.
In a second aspect, the present invention provides a wear-resistant drag chain protection material prepared by the method of any one of the preceding embodiments.
In a third aspect, the present invention provides a cable comprising a cable body, the surface of the cable body being provided with a wear layer prepared from the wear-resistant drag chain protection material of the previous embodiments.
In an alternative embodiment, the cable is a drag chain cable, the drag chain cable further comprising a drag chain, the wear layer being connected to an inner side of the drag chain.
The beneficial effects of the invention include:
The invention can change the dry friction between the wear-resistant drag chain protection material and the internal filling component (such as a cable or an air pipe, etc.) into wet friction by coating the perfluoropolyether lubricating oil on the inner surface of the second shaping material, reduce the friction coefficient and prolong the service life of the material, and can effectively prevent the perfluoropolyether lubricating oil on the inner side of the second shaping material from precipitating to the outer side by coating the tetrafluoro emulsion on the outer side of the outer surface of the second shaping material and carrying out high-temperature curing, thereby limiting the perfluoropolyether lubricating oil in the second shaping material, prolonging the action time of the perfluoropolyether lubricating oil, and improving the cleanliness of the surface of the wear-resistant drag chain protection material and realizing dust-free protection.
The preparation method of the wear-resistant drag chain protection material provided by the invention is simple and easy to operate, the friction coefficient between the drag chain and the protection device can be effectively reduced, and the obtained wear-resistant drag chain protection material has high density, good flexibility, smooth surface, wear resistance and high wear resistance, and is especially suitable for dust-free tank drag chain cables.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is an SEM image of the surface of a wear-resistant tow chain guard material of example 1;
FIG. 2 is a SEM image of a cross section of the wear-resistant drag chain protection material of example 1;
FIG. 3 is an SEM image of the surface of a commercially available dust-free tow cable protective material;
FIG. 4 is an enlarged view of FIG. 3;
FIG. 5 is a graph showing the results of the abrasion resistance test of the second setting material of example 1;
FIG. 6 is a graph of the results of the wear test of the wear-resistant tow chain protection material of example 1;
fig. 7 is a graph of the abrasion resistance test results of a commercially available dust-free drag chain cable protective material.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
The wear-resistant drag chain protection material provided by the invention, and a preparation method and application thereof are specifically described below.
The invention provides a preparation method of a wear-resistant drag chain protection material, which comprises the following steps of mixing polytetrafluoroethylene dispersion resin with a booster, performing extrusion molding to obtain an extrusion base band, performing calendaring treatment on the extrusion base band to obtain a calendaring band, removing the booster in the calendaring band, performing stretching treatment to obtain a stretched film, winding the stretched film on a hard piece, performing first pressing, performing first sintering and shaping to obtain a first shaping material, performing second pressing and then performing second sintering and shaping to obtain a second shaping material, coating a tetrafluoro emulsion on the outer surface of the second shaping material, curing, and coating a perfluoropolyether lubricating oil on the inner surface of the second shaping material.
In some alternative embodiments, the mass ratio of polytetrafluoroethylene dispersion resin to the booster may be 4:1 to 6:1, such as 4:1, 4.5:1, 5:1, 5.5:1, or 6:1, etc., but may be other values in the range of 4:1 to 6:1.
If the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is less than 4:1 (such as 2:1), the content of the solvent in the material is easy to be high, the resistance is reduced when the extrusion is carried out, the extrusion fibrosis degree of the material and the initial strength of the material are reduced, and if the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is more than 6:1 (such as 8:1), the content of the solvent in the material is easy to be less, the resistance is increased when the extrusion is carried out, the material is difficult to extrude, and the material structure is damaged.
In some alternative embodiments, the booster may include, by way of example and not limitation, at least one of an alkane solvent, kerosene, petroleum ether, and paraffin wax. In some preferred embodiments, the booster may be an alkane solvent, more preferably an alkane solvent. In some more typical embodiments, the isoparaffinic solvent has a flash point of 50 ℃ to 80 ℃, a density of 600kg/m 3~900kg/m3, a distillation range of 184 ℃ or more at the initial point, 199 ℃ or less at the final point, and a molecular weight of 150g/mol to 200g/mol. Illustratively, the isoparaffinic solvent may be ISOPAR L, or the like.
By adopting the booster and controlling the mass ratio of the booster to the polytetrafluoroethylene dispersion resin to be 1:4-1:6, the processing performance of the product is improved, the damage to resin fibers in the processing process is avoided, and the strength and other performances of the product are improved.
Further, the mixed raw material obtained by mixing the polytetrafluoroethylene dispersion resin and the booster is extruded and molded by a die, and an extrusion baseband is obtained.
In some alternative embodiments, the extrusion pressure may be 30bar to 40bar, such as 30bar, 35bar, 40bar, etc., or may be other values within the range of 30bar to 40 bar.
Further, the extruded base tape is rolled by a rolling device to obtain a rolled tape.
In some alternative embodiments, the thickness of the calendered tape may be 0.5mm to 0.7mm, such as 0.5mm, 0.55mm, 0.6mm, 0.65mm, or 0.7mm, and the like, as well as other values in the range of 0.5mm to 0.7 mm.
If the thickness of the rolled tape is too thin, the longitudinal and transverse strength is easily small, and the material is easily damaged during longitudinal and transverse stretching, and if the thickness of the rolled tape is too thick, the longitudinal and transverse strength is large, and during longitudinal and transverse stretching, the material cannot be stretched, and the requirement of the subsequent process cannot be met.
Further, the propellant in the rolled strip can be removed in a related conventional manner according to the type of the propellant actually adopted.
Taking an alkane solvent as an example of the booster, the alkane solvent can be volatilized to be completely removed by heating at the temperature of 100-220 ℃. Preferably, the temperature in the degreasing tank is a stepwise region (for example, the temperature distribution is stepwise divided from 100 ℃ to 220 ℃ and heated according to a temperature interval of 10 ℃) during the heating process, so that the solvent evaporation is ensured to be complete and the rolling belt is not adversely affected.
Further, the rolled tape from which the booster is removed is subjected to stretching treatment to obtain a stretched film.
The stretching treatment includes transverse stretching and longitudinal stretching.
The stretching multiple of the transverse stretching can be 8 times to 10 times, such as 8 times, 8.5 times, 9 times, 9.5 times or 10 times, and the like, and can also be other values within the range of 8 times to 10 times.
The transverse stretching may be performed at a temperature of 250 ℃ to 280 ℃, for example, 250 ℃, 255 ℃, 260 ℃, 265 ℃, 270 ℃, 275 ℃, 280 ℃, or the like, or other values within the range of 250 ℃ to 280 ℃.
The stretching ratio in the longitudinal stretching may be 12 times to 16 times, such as 12 times, 12.5 times, 13 times, 13.5 times, 14 times, 14.5 times, 15 times, 15.5 times, or 16 times, or may be other values within a range of 12 times to 16 times.
The longitudinal stretching may be performed at 320 to 400 ℃, and the temperature may be 320, 330, 340, 350, 360, 370, 380, 390, 400, or the like, or may be other values in the range of 320 to 400, for example.
It should be noted that, in the prior art, the transverse stretching multiple of the related rolled strip is about 2-6 times, and the longitudinal stretching multiple is about 10 times or less, and the invention can make the transverse stretching multiple of the rolled strip reach 8-10 times and the longitudinal stretching multiple reach 12-16 times through specific raw materials, specific extrusion pressure, specific rolling thickness, specific removal mode of the booster and specific stretching temperature, thereby being beneficial to improving the performances of the wear-resistant drag chain protection material, such as density, strength and the like.
In some embodiments, the stretched film has a thickness of about 20 μm to about 30 μm.
Further, the stretched film obtained by stretching is wound up, followed by first pressing.
Illustratively, the winding may be a winding, and the hard member may be a steel roller, for example.
The thickness after winding may be 0.8mm to 1.0mm, for example, 0.8mm, 0.85mm, 0.9mm, 0.95mm or 1.0mm, or may be other values within the range of 0.8mm to 1.0 mm.
In some embodiments, the pressure of the first pressing is 0.2 to 1MPa, such as 0.2MPa, 0.3MPa, 0.4MPa, 0.5MPa, 0.6MPa, 0.7MPa, 0.8MPa, 0.9MPa, or 1MPa, etc., and may be other values in the range of 0.2 to 1 MPa.
If the pressure of the first pressing is too small, the gas in the material is not easy to exhaust, and the gas is easy to generate in the material during shaping, so that the bonding between the material layers is reduced, and if the pressure of the first pressing is too large, the thickness of the material is reduced, so that the use is not easy.
The time for the first pressing can be 1 min-2 min, such as 1min, 1.5min or 2 min.
Further, the first sintering setting is performed after the first pressing, and the process may be performed in a high temperature furnace, for example.
In some embodiments, the temperature of the first sintering setting may be 350 ℃ to 380 ℃, such as 350 ℃, 355 ℃, 360 ℃, 365 ℃, 370 ℃, 375 ℃, 380 ℃, or the like, and may be other values within the range of 350 ℃ to 380 ℃.
The time for the first sintering and shaping can be 15-30 min, such as 15min, 20min, 25min or 30min, and other values within 15-30 min can be also used.
Through the sintering setting conditions, the crystal structure of the material can be broken, the resin fibers are connected together, and the density and the strength of the material are improved.
Further, the second pressing is performed after the first sintering and shaping.
In some embodiments, the pressure of the second pressing may be 0.5MPa to 1.5MPa, such as 0.5MPa, 0.6MPa, 0.7MPa, 0.8MPa, 0.9MPa, 1MPa, 1.1MPa, 1.2MPa, 1.3MPa, 1.4MPa, or 1.5MPa, and the like, and may also be other values in the range of 0.5MPa to 1.5 MPa.
In some alternative embodiments, the pressure of the second press may be the same as the pressure of the first press. In some preferred embodiments, the pressure of the second press is not lower than the pressure of the first press.
The second pressing time can be 2 min-3 min, such as 2min, 2.5min or 3 min.
Further, the second sintering and shaping are carried out after the second pressing.
In some embodiments, the temperature of the second sintering setting may be 350 ℃ to 380 ℃, such as 350 ℃, 355 ℃, 360 ℃, 365 ℃, 370 ℃, 375 ℃, or 380 ℃, and the like, and may be other values within the range of 350 ℃ to 380 ℃.
The time for the second sintering and shaping can be 15-30 min, such as 15min, 20min, 25min or 30min, and other values within 15-30 min can be also used.
In the invention, the density and strength of the polytetrafluoroethylene material can be improved by performing the second pressing and the second sintering after the first pressing and the first sintering. Even if the time of the primary pressing mode in the prior art is prolonged or the pressure of the primary pressing is further increased, the secondary pressing effect of the invention cannot be achieved.
Further, the outer surface of the second setting material is coated with a tetrafluoro emulsion and cured.
The above-described coating may be performed by spraying, for example.
The solid content of the tetrafluoro emulsion may be 45% -65%, such as 45%, 50%, 55%, 60% or 65%, and other values within the range of 45% -65% are also possible. In some preferred embodiments, the tetrafluoro emulsion has a solids content of 40% -60%. In some preferred embodiments, the tetrafluoro emulsion has a solids content of 60%.
Accordingly, the coating amount of the tetrafluoro emulsion may be 250mL/m 2~350mL/m2, such as 250mL/m2、260mL/m2、270mL/m2、280mL/m2、290mL/m2、300mL/m2、310mL/m2、320mL/m2、330mL/m2、340mL/m2 or 350mL/m 2, etc., and may be other values in the range of 250mL/m 2~350mL/m2.
It should be noted that if the solid content of the tetrafluoro emulsion is too high or the coating amount of the tetrafluoro emulsion is too high, the uniformity of the sprayed material is poor, and the product performance is further affected, and if the solid content of the tetrafluoro emulsion is too low, the curing time is prolonged and the curing temperature is increased, and the spraying amount is increased, so that the production cost is obviously increased, and the spraying effect is easy to control.
In some embodiments, the curing temperature may be 220 ℃ to 245 ℃, such as 220 ℃, 225 ℃, 230 ℃, 235 ℃, 240 ℃, 245 ℃, or the like, and may be other values within the range of 220 ℃ to 245 ℃.
The curing time may be 15 to 30 minutes, such as 15, 20, 25 or 30 minutes, or may be other values within 15 to 30 minutes.
Further, the inner surface of the second shaping material is coated with the perfluoropolyether lubricating oil, and the mixture is left to stand so that the perfluoropolyether lubricating oil permeates into the second shaping material.
The coating can also be carried out by spraying in the same way. The standing may be performed at room temperature, and the standing time may be, for example, not less than 24 hours.
In some embodiments, the molecular weight of the perfluoropolyether lubricating oil may be 10000g/mol to 15000g/mol.
If the molecular weight of the perfluoropolyether lubricating oil is too small, the perfluoropolyether lubricating oil is precipitated outwards, and thus fails, and if the molecular weight of the perfluoropolyether lubricating oil is too large, the perfluoropolyether lubricating oil is difficult to penetrate into the inside of the sizing material, and even if the perfluoropolyether lubricating oil can penetrate, the corresponding penetration speed is slow, and the perfluoropolyether lubricating oil is difficult to effectively play a role.
The coating amount of the perfluoropolyether lubricating oil can be 150mL/m 2~250mL/m2, such as 150mL/m2、160mL/m2、170mL/m2、180mL/m2、190mL/m2、200mL/m2、210mL/m2、220mL/m2、230mL/m2、240mL/m2 or 250mL/m 2, etc., or can be other values in the range of 150mL/m 2~250mL/m2.
If the coating amount of the perfluoropolyether lubricating oil is too small, the effect is limited, and if the coating amount of the perfluoropolyether lubricating oil is too large, the material is saturated after absorbing, and the surface of the material is adhered with too much perfluoropolyether lubricating oil, so that too much lubricating oil is easily adhered to a drag chain, and the later maintenance and inspection are not facilitated.
The wear-resistant drag chain protection material is characterized in that the inner surface of the second shaping material is coated with the perfluoropolyether lubricating oil in the amount, so that the dry friction between the wear-resistant drag chain protection material and an internal filling component (such as a cable or an air pipe) is changed into wet friction, the friction coefficient is reduced, the service life of the material is prolonged, the outer side of the outer surface of the second shaping material is coated with the tetrafluoro emulsion in the amount, and high-temperature curing is carried out, the perfluoropolyether lubricating oil on the inner side of the second shaping material can be effectively prevented from being separated out to the outer side, the perfluoropolyether lubricating oil can be limited in the second shaping material on one hand, the acting time of the perfluoropolyether lubricating oil is prolonged, and the cleanliness of the surface of the wear-resistant drag chain protection material can be improved on the other hand, so that dust-free protection is realized.
Further, the materials can be cut by a cutting machine according to actual needs.
It should be noted that, other preparation conditions not disclosed in the present invention can refer to related prior art, and are not described herein in detail.
Correspondingly, the invention also provides a wear-resistant drag chain protection material which is prepared by the preparation method.
The wear-resistant drag chain protection material has few surface nodes, is smooth and wear-resistant. The whole wear-resistant drag chain protection material has higher density, flexibility and wear resistance. In the prior art, the drag chain protection material prepared by overlapping polytetrafluoroethylene films has the advantages of low density, obvious surface fiber and poor wear resistance.
In some embodiments, the wear-resistant drag chain protection material provided herein has a density of not less than 1.0g/cm 3, for example, may be 1.0g/cm 3~1.2g/cm3.
In some embodiments, the wear resistant drag chain protection material has a coefficient of friction of no more than 0.1155 and the amount of wear can be reduced to 0.004g.
In addition, the invention also provides application of the wear-resistant drag chain protection material, which can be used for a drag chain device, wherein an inner filling component of the drag chain device can be a cable or an air pipe.
Further, the invention also provides a cable, which comprises a cable body, wherein the surface of the cable body is provided with a wear-resistant layer prepared from the wear-resistant drag chain protection material.
When the cable is a drag chain cable, the drag chain cable comprises a drag chain in addition to a cable body with a wear-resistant layer, the wear-resistant layer being connected to the inner side of the drag chain. That is, the inner surface of the wear-resistant tow chain protection material faces the cable body and the outer surface of the wear-resistant tow chain protection material faces the tow chain.
The drag chain cable has high wear resistance and long service life.
In some preferred embodiments, the drag chain cable is a dust-free tank drag chain cable.
The features and capabilities of the present invention are described in further detail below in connection with the examples.
Example 1
The embodiment provides a wear-resistant drag chain protection material, and the preparation method comprises the following steps:
S1, mixing polytetrafluoroethylene dispersion resin with a booster, and then extruding and molding through a die to obtain an extrusion baseband.
Wherein the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is 5:1, the booster is an isoparaffin solvent, and the model of the booster is ISOPAR L. The extrusion pressure was 35bar.
And S2, carrying out rolling treatment on the extrusion base band on rolling equipment to obtain the rolled band with the thickness of 0.6 mm.
S3, removing the booster in the calendaring belt, and then stretching to obtain a stretched film with the thickness of 25 mu m.
The method comprises the steps of putting a calendaring belt into heating equipment, dividing and heating the temperature distribution from 100 ℃ to 220 ℃ in a10 ℃ temperature interval in a box body in a stepwise manner, so as to volatilize the booster until the booster is completely removed.
The stretching treatment includes transverse stretching and longitudinal stretching. Wherein the stretching multiple of the transverse stretching is 9 times, and the transverse stretching is carried out under the condition of 265 ℃. The stretching ratio in the longitudinal direction was 14 times, and the longitudinal direction was performed at 360 ℃.
And S4, winding the stretched film on a hard piece, performing first pressing, and performing first sintering shaping to obtain a first shaping material.
Wherein, the winding adopts the winding mode, and the hard piece adopts the steel roll, and thickness after the winding is 0.8mm.
The pressure of the first pressing is 0.6MPa, the time of the first pressing is 2min, the temperature of the first sintering shaping is 365 ℃, and the time of the first sintering shaping is 15min.
And S5, carrying out secondary pressing on the primary shaping material, and then carrying out secondary sintering shaping to obtain the secondary shaping material.
The pressure of the second pressing can be 1.2MPa, the time of the second pressing is 2.5min, the temperature of the second sintering shaping is 365 ℃, and the time of the second sintering shaping is 15min.
And S6, coating the outer surface of the second shaping material with the tetrafluoro emulsion, curing, and coating the inner surface of the second shaping material with the perfluoropolyether lubricating oil.
Wherein, spraying polytetrafluoroethylene emulsion with solid content of 60% on the outer surface of the second shaping material according to the spraying amount of 300mL/m 2 in a spraying mode. The curing temperature was 230℃and the time was 20min.
Spraying a perfluoropolyether lubricating oil with molecular weight of 10000g/mol on the inner surface of the second shaping material according to the spraying amount of 200mL/m 2 by adopting a spraying mode, and then standing for 24 hours at room temperature.
Example 2
The embodiment provides a wear-resistant drag chain protection material, and the preparation method comprises the following steps:
S1, mixing polytetrafluoroethylene dispersion resin with a booster, and then extruding and molding through a die to obtain an extrusion baseband.
Wherein the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is 4:1, the booster is isoparaffin solvent, and the model of the booster is ISOPAR L. The extrusion pressure was 30bar.
And S2, carrying out rolling treatment on the extrusion base band on rolling equipment to obtain the rolled band with the thickness of 0.5 mm.
And S3, removing the booster in the calendaring belt, and then performing stretching treatment to obtain a stretched film with the thickness of 20 mu m.
The removal of the booster is to put the calendaring belt into heating equipment, and the temperature distribution is divided stepwise from 100 ℃ to 220 ℃ in a temperature interval of 10 ℃ per minute in the box body so as to volatilize the booster until the booster is completely removed.
The stretching treatment includes transverse stretching and longitudinal stretching. Wherein the stretching multiple of the transverse stretching is 8 times, and the transverse stretching is carried out under the condition of 250 ℃. The stretching ratio in the longitudinal direction was 12 times, and the longitudinal direction was performed at 320 ℃.
And S4, winding the stretched film on a hard piece, performing first pressing, and performing first sintering shaping to obtain a first shaping material.
Wherein, the winding adopts the winding mode, and the hard piece adopts the steel roll, and thickness after the winding is 0.9mm.
The pressure of the first pressing is 0.2MPa, the time of the first pressing is 1min, the temperature of the first sintering setting is 350 ℃, and the time of the first sintering setting is 30min.
And S5, carrying out secondary pressing on the primary shaping material, and then carrying out secondary sintering shaping to obtain the secondary shaping material.
The pressure of the second pressing can be 0.5MPa, the time of the second pressing is 2min, the temperature of the second sintering shaping is 350 ℃, and the time of the second sintering shaping is 30min.
And S6, coating the outer surface of the second shaping material with the tetrafluoro emulsion, curing, and coating the inner surface of the second shaping material with the perfluoropolyether lubricating oil.
Wherein, spraying the polytetrafluoroethylene emulsion with the solid content of 45% on the outer surface of the second shaping material according to the spraying amount of 350mL/m 2 in a spraying mode. The curing temperature was 220℃and the time was 30min.
Spraying a perfluoropolyether lubricating oil with a molecular weight of 12000g/mol on the inner surface of the second shaping material according to a spraying amount of 150mL/m 2 by adopting a spraying mode, and then standing for 36h at room temperature.
Example 3
The embodiment provides a wear-resistant drag chain protection material, and the preparation method comprises the following steps:
S1, mixing polytetrafluoroethylene dispersion resin with a booster, and then extruding and molding through a die to obtain an extrusion baseband.
Wherein the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is 6:1, the booster is an isoparaffin solvent, and the model of the booster is ISOPAR L. The extrusion pressure was 40bar.
And S2, carrying out rolling treatment on the extrusion base band on rolling equipment to obtain the rolled band with the thickness of 0.7 mm.
S3, removing the booster in the calendaring belt, and then performing stretching treatment to obtain a stretched film with the thickness of 30 mu m.
The removal of the booster is to put the calendaring belt into heating equipment, and the temperature distribution is divided stepwise from 100 ℃ to 220 ℃ in a temperature interval of 10 ℃ per minute in the box body so as to volatilize the booster until the booster is completely removed.
The stretching treatment includes transverse stretching and longitudinal stretching. Wherein the stretching multiple of the transverse stretching is 10 times, and the transverse stretching is performed under the condition of 280 ℃. The stretching ratio in the longitudinal direction was 16 times, and the longitudinal direction was performed under the condition of 400 ℃.
And S4, winding the stretched film on a hard piece, performing first pressing, and performing first sintering shaping to obtain a first shaping material.
Wherein, the winding adopts the winding mode, and the hard piece adopts the steel roll, and thickness after the winding is 1.0mm.
The pressure of the first pressing is 1MPa, the time of the first pressing is 1min, the temperature of the first sintering setting is 380 ℃, and the time of the first sintering setting is 20min.
And S5, carrying out secondary pressing on the primary shaping material, and then carrying out secondary sintering shaping to obtain the secondary shaping material.
The pressure of the second pressing can be 1.5MPa, the time of the second pressing is 3min, the temperature of the second sintering shaping is 380 ℃, and the time of the second sintering shaping is 20min.
And S6, coating the outer surface of the second shaping material with the tetrafluoro emulsion, curing, and coating the inner surface of the second shaping material with the perfluoropolyether lubricating oil.
Wherein, spraying the polytetrafluoroethylene emulsion with the solid content of 65% on the outer surface of the second shaping material according to the spraying amount of 250mL/m 2 in a spraying mode. The curing temperature was 245 ℃ and the time was 15min.
Spraying a perfluoropolyether lubricating oil with the molecular weight of 15000g/mol on the inner surface of the second shaping material according to the spraying amount of 250mL/m 2 by adopting a spraying mode, and then standing for 30h at room temperature.
Example 4
This example differs from example 1 in that the pressure and time of the second press are both the same as those of the first press, i.e., the pressure of the second press is 0.6MPa and the time of the second press is 2min.
Example 5
This example differs from example 1 in that the propellant is kerosene.
Example 6
The difference between this example and example 1 is that the booster is petroleum ether.
Example 7
The difference between this example and example 1 is that the booster is paraffin wax.
Comparative example 1
The difference between this comparative example and example 1 is that step S5 is not performed between step S4 and step S6. That is, this comparative example was directly coated with a tetrafluoro emulsion after the first sintering and setting, and no second pressing was performed.
Comparative example 2
The difference between this comparative example and example 1 is that in step S6, the perfluoropolyether lubricating oil is sprayed only on the inner surface of the second setting material, and the tetrafluoro emulsion is not coated and cured on the outer surface of the second setting material.
Comparative example 3
The comparative example differs from example 1 in that the perfluoropolyether lubricating oil and the tetrafluoro emulsion were directly mixed to obtain a mixed spray solution, which was then sprayed onto the inner surface of the second setting material.
Comparative example 4
The comparative example differs from example 1 in that there is no step S6.
Comparative example 5
The difference between this comparative example and example 1 is that the tetrafluoro emulsion has a solids content of 40%.
Comparative example 6
The difference between this comparative example and example 1 is that the tetrafluoro emulsion has a solids content of 70%.
Comparative example 7
The comparative example differs from example 1 in that the sprayed amount of the tetrafluoro emulsion was 200mL/m 2.
Comparative example 8
The comparative example differs from example 1 in that the sprayed amount of the tetrafluoro emulsion was 400mL/m 2.
Comparative example 9
This comparative example differs from example 1 in that the perfluoropolyether lubricating oil has a molecular weight of 5000g/mol.
Comparative example 10
The difference between this comparative example and example 1 is that the molecular weight of the perfluoropolyether lubricating oil is 20000g/mol.
Comparative example 11
This comparative example differs from example 1 in that the coating amount of the perfluoropolyether lubricating oil is 100mL/m 2.
Comparative example 12
This comparative example differs from example 1 in that the coating amount of the perfluoropolyether lubricating oil was 300mL/m 2.
Comparative example 13
The comparative example differs from example 1 in that the mass ratio of polytetrafluoroethylene dispersion resin to the booster is 3:1.
Comparative example 14
The comparative example differs from example 1 in that the mass ratio of polytetrafluoroethylene dispersion resin to the booster is 8:1.
Test examples
① . Taking the wear-resistant drag chain protection material prepared in example 1 as an example, the surface and the cross-section structure of the wear-resistant drag chain protection material are subjected to electron microscope characterization, and the results are shown in fig. 1 and 2.
From fig. 1 and fig. 2, it can be seen that the wear-resistant drag chain protection material prepared in example 1 has lubricating oil adsorbed on the surface and the inside of the material, the surface is treated with solvent, the structural nodes are few, the smoothness is high, and the wear-resistant drag chain protection material has higher density, flexibility and wear resistance.
In addition, the surface of a commercially available dust-free drag chain cable protective material was subjected to electron microscopy characterization, and the results are shown in fig. 3 and 4.
It can be seen from fig. 3 and 4 that some dust-free drag chain cable protection materials on the market have more surface nodes, low baseband density, obvious surface fibers and low surface smoothness.
② . Taking example 1 as an example, the second shaping material obtained in step S5 and the wear-resistant drag chain protection material obtained in step S6 were subjected to wear resistance comparison, the test standard was referred to in GB/T3960, the test temperature was 25 ℃, the environmental humidity was 55%, and the test load was 3kg, and the results are shown in fig. 5 and 6.
As can be seen from FIG. 5, before the surface treatment, the second setting material had a maximum friction coefficient of 0.164969000, a minimum friction coefficient of 0.031903000, an average value of 0.100130911, a mass before abrasion of 0.156g, a mass after abrasion of 0.145g, and an abrasion loss of 0.011g.
As can be seen from FIG. 6, after the surface treatment, the wear-resistant drag chain protection material has a maximum friction coefficient of 0.115495000, a minimum friction coefficient of-0.000660000, an average value of 0.030600543, a mass before wear of 0.160g, a mass after wear of 0.156g and a wear amount of 0.004g.
In addition, the abrasion resistance was measured by the above-mentioned test method using some commercially available dust-free drag chain cable protective material of ① as a control, and the results are shown in fig. 7.
As can be seen from FIG. 7, the commercial dust-free drag chain cable protective material has a maximum friction coefficient of 0.776361000, a minimum friction coefficient of 0.283106000, an average value of 0.50480273, a mass before abrasion of 0.135g, a mass after abrasion of 0.113g and an abrasion loss of 0.022g.
From the above results, it can be seen that the wear-resistant drag chain protection material provided by the embodiment of the invention has higher wear resistance.
③ . The abrasion resistance test was conducted on the abrasion resistant drag chain protection materials obtained in examples 2 to 7 and comparative examples 1 to 14 according to the method in ②, and the results are shown in table 1.
Table 1 test results
As can be seen from Table 1, the wear-resistant drag chain protection material prepared by the embodiment of the invention has better wear resistance than the wear-resistant drag chain protection material prepared by the comparative example.
In conclusion, the preparation method of the wear-resistant towline protection material provided by the invention is simple and easy to operate, the friction coefficient between the towline and the protection material can be effectively reduced, and the obtained wear-resistant towline protection material has the advantages of high density, good flexibility, smooth and wear-resistant surface and high wear resistance, and is particularly suitable for dust-free tank towline cables.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A preparation method of a wear-resistant drag chain protection material is characterized by comprising the steps of mixing polytetrafluoroethylene dispersion resin and a booster, then carrying out extrusion molding to obtain an extrusion baseband, carrying out calendaring treatment on the extrusion baseband to obtain a calendaring belt, removing the booster in the calendaring belt, then carrying out stretching treatment to obtain a stretched film, winding the stretched film on a hard piece, carrying out first pressing and then carrying out first sintering molding to obtain a first molding material, carrying out second pressing and then carrying out second sintering molding to obtain a second molding material, coating a tetrafluoro emulsion on the outer surface of the second molding material, curing, and coating a perfluoropolyether lubricating oil on the inner surface of the second molding material;
the mass ratio of the polytetrafluoroethylene dispersion resin to the booster is 4:1 to 6:1;
The pressure of the first pressing is 0.2-1 MPa, and the time of the first pressing is 1-2 min;
The temperature of the primary sintering setting is 350-380 ℃, and the time of the primary sintering setting is 15-30 min;
the pressure of the second pressing is 0.5-1.5 MPa, and the time of the second pressing is 2 min-3 min;
The temperature of the second sintering and shaping is 350-380 ℃, and the time of the second sintering and shaping is 15-30 min;
the solid content of the tetrafluoro emulsion is 45% -65%, and the coating amount of the tetrafluoro emulsion is 250mL/m 2~350mL/m2;
The coating amount of the perfluoropolyether lubricating oil is 150mL/m 2~250mL/m2, and the molecular weight of the perfluoropolyether lubricating oil is 10000 g/mol-15000 g/mol.
2. The method of claim 1, wherein the boosting agent comprises an alkane solvent.
3. The method of claim 1, wherein the boosting agent comprises at least one of kerosene, petroleum ether, and paraffin wax.
4. The preparation method according to claim 1, wherein the extrusion molding pressure is 30bar to 40bar.
5. The method of claim 1, wherein the thickness of the rolled strip is 0.5mm to 0.7mm.
6. The method of claim 1, wherein the stretching treatment comprises transverse stretching and longitudinal stretching;
Wherein the stretching multiple of the transverse stretching is 8-10 times, and the transverse stretching is carried out under the condition of 250-280 ℃;
The stretching multiple of the longitudinal stretching is 12-16 times, and the longitudinal stretching is performed under the condition of 320-400 ℃.
7. The method according to any one of claims 1 to 6, wherein the curing temperature is 220 ℃ to 245 ℃ and the curing time is 15min to 30min.
8. The wear-resistant drag chain protection material is characterized by being prepared by the preparation method of any one of claims 1-7.
9. A cable comprising a cable body, the surface of the cable body being provided with a wear layer made of the wear-resistant drag chain protection material of claim 8.
10. The cable of claim 9, wherein the cable is a drag chain cable further comprising a drag chain, the wear layer being coupled to an inner side of the drag chain.
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| EP1199340B1 (en) * | 2000-10-19 | 2005-03-09 | Soft99 Corporation | Paintwork coating composition and coating cloth |
| CN104043347B (en) * | 2014-04-30 | 2016-01-20 | 桐乡市健民过滤材料有限公司 | Lower resistance is wear-resistant microporous teflon membran and preparation method thereof |
| KR101890986B1 (en) * | 2016-05-26 | 2018-08-23 | 엘에스전선 주식회사 | Multi sleeve for cables support apparatus and cables support apparatus comprising the same |
| CN116598050A (en) * | 2023-06-30 | 2023-08-15 | 瑞鑫集团有限公司 | Torsion-resistant cable |
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| CN105666889A (en) * | 2016-02-01 | 2016-06-15 | 天津市天塑科技集团有限公司 | Preparation method of high-intensity teflon film |
| CN111976173A (en) * | 2019-05-24 | 2020-11-24 | 安徽省众望科希盟科技有限公司 | Preparation process of unidirectional stretching polytetrafluoroethylene film |
| CN110898255A (en) * | 2019-12-06 | 2020-03-24 | 上海康宁医疗用品有限公司 | Method for manufacturing expanded polytetrafluoroethylene facial implant with coated surface |
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