Oil-resistant high-temperature-resistant nylon material based on pipe clamp and preparation method of oil-resistant high-temperature-resistant nylon material

Abstract

The invention relates to the technical field of composite materials, in particular to an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp and a preparation method of the oil-resistant and high-temperature-resistant nylon material. In order to improve the high temperature resistance and oil resistance of the plastic pipe clamp, the nylon material with oil resistance and high temperature resistance is prepared; the preparation method comprises the following steps: firstly, taking diphenylmethane diisocyanate as a raw material, mixing the diphenylmethane diisocyanate with 1, 1, 3, 3-tetramethyldisiloxane containing a silicon-hydrogen bond to react, so as to prepare silane modified diisocyanate containing an aromatic benzene ring structure and a silicon-oxygen bond structure, and limiting movement and decomposition of a polyamide molecular chain at a high temperature by utilizing a benzene ring and a silicon-oxygen bond, so as to prepare the silane modified diisocyanate containing the aromatic benzene ring structure and the silicon-oxygen bond structure. The high temperature resistance and the oil agent corrosion resistance are enhanced; on the basis, dibasic acid is limited, long-carbon-chain dodecanedioic acid is used as the dibasic acid for reaction, the problem that rigidity is too large due to excessive aromatic benzene in silane modified diamine is avoided, and then the mechanical performance of the pipe clamp is improved.

Description

Technical Field

[0001] The invention relates to the technical field of composite materials, in particular to an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp and a preparation method thereof. Background Art

[0002] Pipe clamps are a type of fixing tool used to fix pipes. According to their types, they can be divided into stainless steel pipe clamps, cast iron pipe clamps and plastic pipe clamps. Among them, plastic pipe clamps are widely used in electricity, petroleum, chemical and pharmaceutical fields due to their light weight, corrosion resistance and good insulation. However, due to the properties of plastics themselves, plastic pipe clamps have poor high-temperature performance. After a long time in a high-temperature environment, performance degradation will occur. In addition, plastics are not resistant to oil immersion and are prone to performance degradation, which greatly limits the application of plastic pipe clamps. Summary of the invention

[0003] The object of the present invention is to provide an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0005] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0006] S11. Under a nitrogen atmosphere, diphenylmethane diisocyanate was dispersed in toluene, the temperature was raised to 105±5°C, the temperature was kept for 5-10 minutes, and then the temperature was cooled to 10±5°C. Then, 1,1,3,3-tetramethyldisiloxane was uniformly added dropwise within 1-2 hours, and stirring was continued during the addition. After the addition was completed, the temperature was raised to 68±2°C, and the reaction was stirred under reflux for 0.5-2 hours, and then the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0007] S12. The silane-modified diisocyanate is dispersed in pure xylene, and ultrasonically mixed for 40-80 min to obtain a silane-modified diisocyanate dispersion;

[0008] Disperse bis(4-aminophenoxy)dimethylsilane in xylene, disperse with ultrasonic oscillation for 3-5 minutes, add dibutyl bis(2-ethylhexanoate)tin, continue mixing for 15-20 minutes, uniformly add silane-modified diisocyanate dispersion thereto within 2-4 hours, raise the temperature to 95±10°C after the addition is completed, stir and react for 2-5 hours, and then remove excess solvent by rotary evaporation to obtain silane-modified diamine;

[0009] S13: Disperse silane-modified diamine, dodecanedioic acid and phosphorous acid in N,N-dimethylformamide, stir and mix for 15-40 minutes, protect under nitrogen atmosphere, set the air pressure to 10-50 kPa, heat to 130-150°C, keep warm for 2-4 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 10-50 kPa again, heat to 280-300°C, keep warm for 2-3 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0010] S2. Mix polyamide 66 with oil-resistant and high-temperature-resistant modified polyamide and a compatibilizer, raise the temperature to 270°C, blend for 3-5 minutes, add glass fiber and inorganic filler, antioxidant and dispersant, continue blending for 5-8 minutes, extrude and pelletize to obtain an oil-resistant and high-temperature-resistant nylon material.

[0011] Furthermore, the oil-resistant and high-temperature-resistant nylon material comprises, by weight, 50-65 parts of polyamide 66, 20-25 parts of modified polyamide, 18-35 parts of glass fiber, 5-8 parts of inorganic filler, 0.5-1 part of compatibilizer, 0.5-1.5 parts of antioxidant, and 0.3-0.8 parts of dispersant.

[0012] Furthermore, in terms of parts by weight, in step S11, the mass ratio of diphenylmethane diisocyanate to 1,1,3,3-tetramethyldisiloxane is 10:(2-2.7).

[0013] Furthermore, in step S12, the mass ratio of the silane-modified diisocyanate, bis(4-aminophenoxy)dimethylsilane, and dibutyl bis(2-ethylhexanoate)tin is 10:(7-8.7):(0.05-0.12) in parts by weight.

[0014] Furthermore, in terms of weight, in step S13, the mass ratio of the silane-modified diamine, dodecanedioic acid, and phosphorous acid is 10:(2-2.2):(0.08-0.15).

[0015] Furthermore, the inorganic filler is antimony trioxide; and the compatibilizer is any one of polyoxyethylene alkyl alcohol amide and polyoxyethylene alkyl amine.

[0016] Furthermore, the antioxidant is bis(2,4-di-p-isopropylphenyl)pentaerythritol diphosphite; and the dispersant is any one of silicone and calcium stearate.

[0017] Furthermore, an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp is prepared by the above method.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0019] In order to improve the high temperature resistance and oil resistance of the plastic pipe clamp, the present invention prepares a nylon material with oil and high temperature resistance; the present invention first uses diphenylmethane diisocyanate as a raw material, and mixes it with 1,1,3,3-tetramethyldisiloxane containing a silicon-hydrogen bond to react, thereby preparing a silane-modified diisocyanate containing an aromatic benzene ring structure and a silicon-oxygen bond structure, wherein the conjugated structure of the benzene ring is highly stable, which can enhance the structural stability of polyamide in a high temperature environment, and the presence of the benzene ring also limits the movement of the polyamide molecular chain, limits the twisting and rotation of the molecular chain, and inhibits the movement of the chain at high temperature, so that the pipe clamp still has a considerable working performance at high temperature, and the silicon-oxygen bond has a higher bond energy than the carbon-carbon bond, and the silicon element has a strong electronegativity, which can attract the aggregation of the molecular chain, while enhancing the resistance to external erosion, thereby realizing the resistance of polyamide to external oil agents;

[0020] On this basis, the present invention further utilizes bis(4-aminophenoxy)dimethylsilane to react with silane-modified diisocyanate, thereby further increasing the content of silicon-oxygen bonds and benzene rings in the reaction product. At the same time, the present invention also limits the dibasic acid and uses dodecanedioic acid as the dibasic acid. Compared with conventional short-chain dibasic acids, dodecanedioic acid has a longer carbon chain, which can effectively avoid the problem of excessive rigidity caused by excessive aromatic benzene rings in silane-modified diamines, improve the compatibility between the synthesized oil-resistant and high-temperature-resistant modified polyamide and polyamide 66, and avoid the incompatibility between the two due to excessive differences. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The glass fiber used in this application has a diameter of 13 μm and a length of 3-4.5 mm; the polyamide 66 used is American DuPont 101L polyamide 66;

[0023] Embodiment 1. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0024] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0025] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, with continuous stirring during the addition. After the addition was completed, the temperature was raised to 68 ° C, and the reaction was refluxed with stirring for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0026] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0027] Disperse 7 parts of bis(4-aminophenoxy)dimethylsilane in xylene, disperse with ultrasonic vibration for 3 minutes, add 0.08 parts of dibutyltin bis(2-ethylhexanoate), continue mixing for 15 minutes, and then uniformly add silane-modified diisocyanate dispersion within 2 hours. After the addition is completed, heat to 90°C, stir and react for 2 hours, and then remove excess solvent by rotary evaporation.

[0028] Obtaining silane-modified diamine;

[0029] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0030] S2. According to the weight proportions, 60 parts of polyamide 66, 20 parts of oil-resistant and high-temperature-resistant modified polyamide, and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0031] Embodiment 2. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0032] Compared with Example 1, this embodiment increases the amount of oil-resistant and high-temperature-resistant modified polyamide added in step S2;

[0033] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0034] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, with continuous stirring during the addition. After the addition was completed, the temperature was raised to 68 ° C, and the reaction was refluxed with stirring for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0035] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0036] Disperse 7 parts of bis(4-aminophenoxy)dimethylsilane in xylene, disperse with ultrasonic vibration for 3 minutes, add 0.08 parts of dibutyltin bis(2-ethylhexanoate), continue mixing for 15 minutes, and then uniformly add silane-modified diisocyanate dispersion within 2 hours. After the addition is completed, heat to 90°C, stir and react for 2 hours, and then remove excess solvent by rotary evaporation.

[0037] Obtaining silane-modified diamine;

[0038] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0039] S2. According to the weight proportions, 60 parts of polyamide 66, 25 parts of oil-resistant and high-temperature-resistant modified polyamide, and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then the mixture is extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0040] Embodiment 3. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0041] Compared with Example 1, this example increases the amount of 1,1,3,3-tetramethyldisiloxane added in step S11;

[0042] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0043] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2.7 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, stirring continuously during the addition process. After the addition was completed, the temperature was raised to 68 ° C, refluxed and stirred for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0044] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0045] Disperse 7 parts of bis(4-aminophenoxy)dimethylsilane in xylene, disperse under ultrasonic vibration for 3 minutes, add 0.08 parts of dibutyl bis(2-ethylhexanoate)tin, continue mixing for 15 minutes, and then uniformly dropwise add silane-modified diisocyanate dispersion within 2 hours. After the dropwise addition is completed, heat to 90°C, stir and react for 2 hours, and then remove excess solvent by rotary evaporation to obtain silane-modified diamine;

[0046] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0047] S2. According to the weight proportions, 60 parts of polyamide 66, 20 parts of oil-resistant and high-temperature-resistant modified polyamide, and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0048] Embodiment 4. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0049] Compared with Example 1, the present embodiment increases the amount of bis(4-aminophenoxy)dimethylsilane added in step S12;

[0050] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0051] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, with continuous stirring during the addition. After the addition was completed, the temperature was raised to 68 ° C, and the reaction was refluxed with stirring for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0052] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0053] 8.7 parts of bis(4-aminophenoxy)dimethylsilane were dispersed in xylene, and after ultrasonic dispersion for 3 minutes, 0.08 parts of dibutyltin bis(2-ethylhexanoate) were added, and the mixture was mixed for 15 minutes. Then, the silane-modified diisocyanate dispersion was uniformly added dropwise within 2 hours. After the addition was completed, the mixture was heated to 90° C., stirred for reaction for 2 hours, and then the excess solvent was removed by rotary evaporation to obtain a silane-modified diamine.

[0054] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0055] S2. According to the weight proportions, 60 parts of polyamide 66, 20 parts of oil-resistant and high-temperature-resistant modified polyamide, and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0056] Embodiment 5. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0057] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0058] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2.7 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, stirring continuously during the addition process. After the addition was completed, the temperature was raised to 68 ° C, refluxed and stirred for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0059] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0060] 8.7 parts of bis(4-aminophenoxy)dimethylsilane were dispersed in xylene, and after ultrasonic dispersion for 3 minutes, 0.08 parts of dibutyltin bis(2-ethylhexanoate) were added, and the mixture was mixed for 15 minutes. Then, the silane-modified diisocyanate dispersion was uniformly added dropwise within 2 hours. After the addition was completed, the mixture was heated to 90° C., stirred for reaction for 2 hours, and then the excess solvent was removed by rotary evaporation to obtain a silane-modified diamine.

[0061] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0062] S2. According to the weight proportions, 60 parts of polyamide 66, 20 parts of oil-resistant and high-temperature-resistant modified polyamide, and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0063] Comparative Example 1. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0064] Compared with Example 1, this comparative example did not prepare the oil-resistant and high-temperature-resistant modified polyamide;

[0065] S1. According to weight proportions, 60 parts of polyamide 66, 23 parts of glass fiber, 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant, and 0.5 parts of calcium stearate dispersant are mixed, the temperature is raised to 270°C, and the mixture is continuously blended for 8 minutes, and then extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0066] Comparative Example 2. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, comprising the following steps:

[0067] Compared with Example 1, this comparative example increases the amount of oil-resistant and high-temperature-resistant modified polyamide added in step S2;

[0068] S1. Preparation of oil-resistant and high temperature-resistant modified polyamide;

[0069] S11. In parts by weight, under a nitrogen atmosphere, 10 parts of diphenylmethane diisocyanate were dispersed in toluene, heated to 105 ° C, kept warm for 5 minutes, cooled to 10 ° C, and 2 parts of 1,1,3,3-tetramethyldisiloxane were uniformly added dropwise within 2 hours, with continuous stirring during the addition. After the addition was completed, the temperature was raised to 68 ° C, and the reaction was refluxed with stirring for 0.5 hours, and the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate;

[0070] S12. In parts by weight, 10 parts of silane-modified diisocyanate were dispersed in pure xylene and mixed by ultrasonic oscillation for 40 min to obtain a silane-modified diisocyanate dispersion;

[0071] Disperse 7 parts of bis(4-aminophenoxy)dimethylsilane in xylene, disperse with ultrasonic vibration for 3 minutes, add 0.08 parts of dibutyltin bis(2-ethylhexanoate), continue mixing for 15 minutes, and then uniformly add silane-modified diisocyanate dispersion within 2 hours. After the addition is completed, heat to 90°C, stir and react for 2 hours, and then remove excess solvent by rotary evaporation.

[0072] Obtaining silane-modified diamine;

[0073] S13: Disperse 10 parts of silane-modified diamine, 2 parts of dodecanedioic acid, and 0.1 parts of phosphorous acid into N,N-dimethylformamide by weight, stir and mix for 15 minutes, protect under nitrogen atmosphere, set the air pressure to 40 kPa, heat to 140°C, keep warm for 3 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 40 kPa again, heat to 290°C, keep warm for 2 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide;

[0074] S2. According to the weight proportions, 60 parts of polyamide 66, 60 parts of oil-resistant and high-temperature-resistant modified polyamide and 1 part of polyoxyethylene alkyl alcohol amide compatibilizer are mixed, the temperature is raised to 270°C, and after blending for 3 minutes, 23 parts of glass fiber and 5 parts of antimony trioxide inorganic filler, 1 part of bis(2,4-diisopropylphenyl)pentaerythritol diphosphite antioxidant and 0.5 part of calcium stearate dispersant are added, and the blending is continued for 8 minutes, and then the mixture is extruded and pelletized to obtain an oil-resistant and high-temperature-resistant nylon material.

[0075] Testing: The oil-resistant and high-temperature-resistant nylon materials prepared in Examples 1-5 and Comparative Examples 1-2 were injection molded into test samples, and the tensile strength of the samples prepared in Examples 1-5 and Comparative Examples 1-2 was tested according to ISO527-2; the bending strength of the samples prepared in Examples 1-5 and Comparative Examples 1-2 was tested according to ISO178;

[0076] The samples prepared in Examples 1-5 and Comparative Examples 1-2 were placed in an oven at 140°C for 1000 hours, and then their tensile strength and flexural strength were tested again;

[0077] The samples prepared in Example 1-5 and Comparative Example 1-2 were immersed in 98# gasoline at 25°C for 5 days and then taken out to test their weight changes. The test results are shown in the table below.

[0078]

[0079] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp, characterized in that: The following steps are involved: S1. Preparation of oil-resistant and high temperature-resistant modified polyamide; S11. Under a nitrogen atmosphere, diphenylmethane diisocyanate was dispersed in toluene, the temperature was raised to 105±5°C, the temperature was kept for 5-10 minutes, and then the temperature was cooled to 10±5°C. Then, 1,1,3,3-tetramethyldisiloxane was uniformly added dropwise within 1-2 hours, and stirring was continued during the addition. After the addition was completed, the temperature was raised to 68±2°C, and the reaction was stirred under reflux for 0.5-2 hours, and then the excess solvent was removed by rotary evaporation to obtain a silane-modified diisocyanate; S12. The silane-modified diisocyanate is dispersed in pure xylene, and ultrasonically mixed for 40-80 min to obtain a silane-modified diisocyanate dispersion; Disperse bis(4-aminophenoxy)dimethylsilane in xylene, disperse with ultrasonic oscillation for 3-5 minutes, add dibutyl bis(2-ethylhexanoate)tin, continue mixing for 15-20 minutes, uniformly add silane-modified diisocyanate dispersion thereto within 2-4 hours, raise the temperature to 95±10°C after the addition is completed, stir and react for 2-5 hours, and then remove excess solvent by rotary evaporation to obtain silane-modified diamine; S13: Disperse silane-modified diamine, dodecanedioic acid and phosphorous acid in N,N-dimethylformamide, stir and mix for 15-40 minutes, protect under nitrogen atmosphere, set the air pressure to 10-50 kPa, heat to 130-150°C, keep warm for 2-4 hours, replace the gas atmosphere with pure nitrogen, adjust the air pressure to 10-50 kPa again, heat to 280-300°C, keep warm for 2-3 hours, restore the air pressure, cool and discharge, and obtain oil-resistant and high-temperature-resistant modified polyamide; S2. Mix polyamide 66 with oil-resistant and high-temperature-resistant modified polyamide and a compatibilizer, raise the temperature to 270°C, blend for 3-5 minutes, add glass fiber and inorganic filler, antioxidant and dispersant, continue blending for 5-8 minutes, extrude and pelletize to obtain an oil-resistant and high-temperature-resistant nylon material.

2. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: The oil-resistant and high-temperature-resistant nylon material comprises, by weight, 50-65 parts of polyamide 66, 20-25 parts of modified polyamide, 18-35 parts of glass fiber, 5-8 parts of inorganic filler, 0.5-1 part of compatibilizer, 0.5-1.5 parts of antioxidant, and 0.3-0.8 parts of dispersant.

3. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: In terms of parts by weight, in step S11, the mass ratio of diphenylmethane diisocyanate to 1,1,3,3-tetramethyldisiloxane is 10:(2-2.7).

4. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: In terms of weight, in step S12, the mass ratio of the silane-modified diisocyanate, bis(4-aminophenoxy)dimethylsilane, and dibutyl bis(2-ethylhexanoate)tin is 10:(7-8.7):(0.05-0.12).

5. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: In terms of weight, in step S13, the mass ratio of the silane-modified diamine, dodecanedioic acid, and phosphorous acid is 10:(2-2.2):(0.08-0.15).

6. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: The inorganic filler is antimony trioxide; the compatibilizer is any one of polyoxyethylene alkyl alcohol amide and polyoxyethylene alkyl amine.

7. The method for preparing an oil-resistant and high-temperature-resistant nylon material based on a pipe clamp according to claim 1, characterized in that: The antioxidant is bis(2,4-di-p-isopropylphenyl)pentaerythritol diphosphite; and the dispersant is any one of silicone and calcium stearate.

8. An oil-resistant and high-temperature-resistant nylon material based on a pipe clamp prepared by the preparation method according to any one of claims 1 to 7.

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