Thermoplastic elastomer foam material and preparation and replacement methods thereof

Abstract

The invention relates to the technical field of high polymer material processing, in particular to a thermoplastic elastomer foam material and a preparation and replacement method, and is characterized in that the thermoplastic elastomer foam material is prepared from the following raw materials in parts by weight: 75-100 parts of thermoplastic elastomer, 0.05-5 parts of antioxidant and 0.5-25 parts of fiber; the invention provides an elastic foaming material with higher mechanical strength as well as a production method and a replacement process thereof. The elastomer added with the fiber auxiliary agent is placed in a mould pressing foaming machine to be foamed, and the physical property of the foaming material in air is more stable after replacement process treatment. Compared with the prior art, the elastomer foaming material provided by the invention has the excellent properties of higher mechanical tensile strength, more stable storage in air after replacement process treatment and the like.

Description

Technical Field

[0001] The invention relates to the technical field of polymer material processing, in particular to a thermoplastic elastomer foaming material, and a preparation and replacement method thereof. Background Art

[0002] In the field of polymer material processing technology, thermoplastic elastomer foam materials are widely used due to their unique flexibility and processability; however, the thermoplastic elastomer foam materials in the prior art have a series of problems in the preparation and use process, which seriously affect their performance and application effect.

[0003] First, during the physical foaming process, when the foaming agent and air are exchanged, the bubble pores of the elastomer foam material often experience severe shrinkage. When CO2 is used as a physical foaming agent, after the foaming is completed, CO2 quickly escapes from the bubble structure, causing the pressure inside the bubble pores to be lower than the ambient atmospheric pressure, forming a vacuum state, which in turn causes the polyamide elastomer foam material to shrink significantly in volume. Although the air will gradually diffuse into the bubble pores, causing the internal pressure to gradually increase, the volume of the shrunk foam material can often only be partially restored, or even cannot be restored, which seriously affects the dimensional stability and performance of the product.

[0004] Secondly, although the existing foam plastic molding process includes stages such as gas dissolution, bubble nucleus formation and growth, and bubble solidification and consolidation, it still faces many challenges in actual operation; for example, compared with autoclave foaming and injection molding foaming, the continuous extrusion foaming method has a shorter holding time and a narrower foaming window, resulting in a limited foaming ratio, generally less than 10 times; at the same time, the equipment used in this method is large, occupies a large space, and has strict process requirements, which increases production costs and operational difficulty.

[0005] In addition, although the thermoplastic polyamide elastomer blended foaming materials in the prior art have solved to a certain extent the problems of severe volume shrinkage, poor recovery, and cell collapse and rupture of the foaming materials caused by low melt strength and matrix modulus, low linear molecular chain strength and elasticity, etc., they have not fundamentally solved the problems of gas loss in the foaming material, material volume shrinkage, and changes in physical properties caused by the different concentrations of supercritical fluid in the foam and the air.

[0006] In addition, some existing technologies use a two-step method of gas impregnation and foaming. Although foamed materials can be prepared, the pressure release takes a long time, the efficiency is low, and additional space costs are required to store the impregnated polymer particles, which increases product costs. At the same time, the stability of the foamed material prepared by this method in the air still needs to be improved.

[0007] In summary, the thermoplastic elastomer foam materials in the prior art have many deficiencies in the preparation and use processes, such as volume shrinkage, changes in physical properties, and poor mechanical properties; therefore, there is an urgent need for a new thermoplastic elastomer foam material and a preparation method thereof to solve the above problems and meet market demand. Summary of the invention

[0008] In view of the above problems, the present invention aims to provide an elastomeric foam material with higher strength and solve the problem of volume shrinkage and other physical property changes of foamed products in the air. The present invention provides an elastic foam material with higher mechanical strength and its production method and replacement process. The elastomer added with fiber additives is placed in a molding foaming machine for foaming, and the physical properties of the foamed material in the air are made more stable after the replacement process. Compared with the existing technology, the elastomeric foam material provided by the present invention has excellent properties such as higher mechanical strength and more stable storage in the air after the replacement process.

[0009] To achieve the above purpose, the technical solution adopted by the present invention is: a thermoplastic elastomer foam material provided by the present invention is prepared from raw materials including the following components: 75-100 parts by weight of thermoplastic elastomer, 0.05-5 parts by weight of antioxidant, and 0.5 to 25 parts by weight of fiber.

[0010] The thermoplastic elastomer is one of thermoplastic polyamide elastomer, thermoplastic polyurethane and polyolefin elastomer.

[0011] The antioxidant is one of antioxidant 168, antioxidant 944, antioxidant 327 and antioxidant 1098.

[0012] The fiber: The glass fiber is alkali-free glass fiber modified by a silane coupling agent, and the diameter of the glass fiber is 8-15 microns.

[0013] The mixing process is as follows: accurately weigh various materials, add various raw materials and processing aids into a high-speed mixer, stir for 2-10 minutes, mix evenly, and obtain mixed raw materials.

[0014] The extrusion process is as follows: feeding the mixed material into a single-screw extruder, setting the front zone temperature to 120-200°C and the die head to 140-200°C; the single screw speed is 10-30rpm, the melt pump speed is 0.5-2.5rpm, and extruding the sheet from the die head.

[0015] The thickness of the obtained TPAE sheet is 6-25 mm, more preferably 8-18 mm, and most preferably 10-15 mm.

[0016] The obtained elastic body sheet is placed in a molding foaming machine, supercritical fluid CO2 is introduced, and it is soaked for 2-8 hours under the conditions of 100-200°C and 7-20MPa, and the foaming material is obtained after rapid pressure release and foaming.

[0017] The foaming material is placed in a displacement reaction kettle, gas is introduced into the kettle, and the reaction kettle is immersed for 2-11 days at a pressure of 0.3-10 MPa. The kettle is opened to obtain a thermoplastic elastomer with high mechanical strength and stable physical properties in the air.

[0018] The present invention aims at the problems of volume shrinkage and other physical property changes and poor mechanical properties of thermoplastic elastomer foam materials in the prior art during the foaming process, and optimizes and improves the performance of the foam material through specific raw material ratios, processing technology and replacement treatment. Compared with the prior art, the present invention provides a thermoplastic elastomer foam material, preparation and replacement method, which achieves the following technical effects:

[0019] (I) Significantly improve mechanical properties: By adding a specific proportion of fiber additives to the thermoplastic elastomer foam material of the present invention and undergoing a specific mixing and extrusion process, the fibers are evenly distributed in the foam material, and as a reinforcing phase, the overall mechanical properties of the foam material are significantly improved. This improvement enables the foam material to have better resistance to external forces and broadens its application range.

[0020] (II) Effectively inhibiting volume shrinkage: The present invention effectively solves the volume shrinkage problem of the foaming material in the subsequent storage process in the prior art through replacement treatment. In the replacement process, by controlling the pressure, time and gas type, the pore structure inside the foaming material is made more stable, the volume change caused by gas escape is reduced, and the dimensional stability of the product is ensured.

[0021] (III) Improved physical property stability: After the replacement treatment, the foamed material exhibits more stable physical properties under normal temperature, pressure and air conditions. This improvement enables the foamed material to maintain its original performance characteristics relatively more when used for a long time or exposed to different environmental conditions, thus extending the service life of the product.

[0022] (IV) Improved production efficiency: The present invention adopts a single screw extruder for sheet preparation. Compared with the twin screw tandem equipment in the prior art, the equipment structure is simpler, occupies a small area, and has relatively low process requirements. At the same time, by optimizing the extrusion process parameters, such as temperature, rotation speed and die head design, the production efficiency and product quality stability are improved.

[0023] (V) Environmental protection and sustainability: The thermoplastic elastomer, antioxidant, fiber and other materials used in the present invention meet environmental protection requirements, and the waste generated during the production process is relatively small and easy to recycle and treat. In addition, by optimizing the foaming and replacement processes, the use and emission of gases are reduced, the impact on the environment is reduced, and it is in line with the concept of sustainable development. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention, but it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should all be deemed to fall within the scope of protection of the present invention.

[0025] Example 1 A thermoplastic elastomer foam material, preparation and replacement method

[0026] A thermoplastic elastomer foam material is prepared from the following components:

[0027] Thermoplastic polyamide elastomer TPAE (Singapore Dollar 20012): 92.5 parts by weight;

[0028] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0029] Fiber (alkali-free glass fiber modified by silane coupling agent): 5 parts by weight

[0030] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0031] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0032] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0033] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, and the pressure is increased to 1.5 MPa. After immersion for 2 days, the reactor is opened to obtain a TPAE foaming material with stable physical properties.

[0034] Example 2 A thermoplastic elastomer foam material, preparation and replacement method

[0035] A thermoplastic elastomer foam material is prepared from the following components:

[0036] Thermoplastic polyamide elastomer TPAE (Singapore Dollar 20012): 87.5 parts by weight;

[0037] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0038] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0039] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0040] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0041] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0042] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, and the pressure is increased to 1.5 MPa. After immersion for 2 days, the reactor is opened to obtain a TPAE foaming material with stable physical properties.

[0043] Example 3 A thermoplastic elastomer foam material, preparation and replacement method

[0044] A thermoplastic elastomer foam material is prepared from the following components:

[0045] Thermoplastic polyamide elastomer TPAE (Singapore Dollar 20012): 77.5 parts by weight;

[0046] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0047] Fiber (alkali-free glass fiber modified by silane coupling agent): 20 parts by weight

[0048] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0049] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0050] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0051] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, and the pressure is increased to 1.5 MPa. After immersion for 2 days, the reactor is opened to obtain a TPAE foaming material with stable physical properties.

[0052] Example 4 A thermoplastic elastomer foam material, preparation and replacement method

[0053] A thermoplastic elastomer foam material is prepared from the following components:

[0054] Thermoplastic polyamide elastomer TPAE (Singapore Dollar 20012): 87.5 parts by weight;

[0055] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0056] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0057] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0058] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0059] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0060] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 2 days to obtain a TPAE foaming material with stable physical properties.

[0061] Example 5 A thermoplastic elastomer foam material, preparation and replacement method

[0062] A thermoplastic elastomer foam material is prepared from the following components:

[0063] Thermoplastic polyurethane TPU (Huntsman 5039): 87.5 parts by weight;

[0064] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0065] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0066] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0067] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPU sheets.

[0068] 2. The obtained TPU sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 4 hours at 140°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0069] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, and the pressure is increased to 3 MPa. After immersion for 2 days, the reactor is opened to obtain a TPU foaming material with stable physical properties.

[0070] Example 6 A thermoplastic elastomer foam material, preparation and replacement method

[0071] A thermoplastic elastomer foam material is prepared from the following components:

[0072] Polyolefin elastomer POE (ExxonMobil 6202): 87.5 parts by weight;

[0073] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0074] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0075] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0076] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain POE sheets.

[0077] 2. The obtained POE sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 6 hours at 70°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0078] 3. The obtained foaming material is placed in a displacement reaction kettle, the kettle is closed, gas is introduced, the pressure is increased to 3 MPa, and the kettle is opened after immersion for 2 days to obtain a POE foaming material with stable physical properties.

[0079] Example 7 A thermoplastic elastomer foam material, preparation and replacement method

[0080] A thermoplastic elastomer foam material is prepared from the following components:

[0081] Polyolefin elastomer POE (ExxonMobil 6202): 87.5 parts;

[0082] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0083] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0084] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0085] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain POE sheets.

[0086] 2. The obtained POE sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 6 hours at 70°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0087] 3. The obtained foaming material is placed in a displacement reaction kettle, the kettle is closed, gas is introduced, the pressure is increased to 3 MPa, and the kettle is opened after immersion for 5 days to obtain a POE foaming material with stable physical properties.

[0088] Example 8 A thermoplastic elastomer foam material, preparation and replacement method

[0089] A thermoplastic elastomer foam material is prepared from the following components:

[0090] Thermoplastic polyurethane TPU (Huntsman 5039): 87.5 parts;

[0091] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0092] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0093] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0094] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPU sheets.

[0095] 2. The obtained TPU sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 4 hours at 140°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0096] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 5 days to obtain a TPU foaming material with stable physical properties.

[0097] Example 9 A thermoplastic elastomer foam material, preparation and replacement method

[0098] A thermoplastic elastomer foam material is prepared from the following components:

[0099] Thermoplastic polyamide elastomer TPAE (SGD 20012): 87.5 parts;

[0100] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0101] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0102] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0103] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0104] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0105] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 5 days to obtain a TPAE foaming material with stable physical properties.

[0106] Example 10 A thermoplastic elastomer foam material, preparation and replacement method

[0107] A thermoplastic elastomer foam material is prepared from the following components:

[0108] Polyolefin elastomer POE (ExxonMobil 6202): 87.5 parts;

[0109] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0110] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0111] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0112] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain POE sheets.

[0113] 2. The obtained POE sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 6 hours at 70°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0114] 3. The obtained foaming material is placed in a displacement reaction kettle, the kettle is closed, gas is introduced, the pressure is increased to 3 MPa, and the kettle is opened after immersion for 8 days to obtain a POE foaming material with stable physical properties.

[0115] Example 11 A thermoplastic elastomer foam material, preparation and replacement method

[0116] A thermoplastic elastomer foam material is prepared from the following components:

[0117] Thermoplastic polyurethane TPU (Huntsman 5039): 87.5 parts;

[0118] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0119] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0120] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0121] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPU sheets.

[0122] 2. The obtained TPU sheet is placed in a molding foaming machine, and the thickness of the sheet is 12 mm. CO2 supercritical fluid is introduced, and it is infiltrated for 4 hours at 140°C and 11 MPa. The foamed material is obtained after rapid pressure release and foaming at a speed of 30 MPa / s.

[0123] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 8 days to obtain a TPU foaming material with stable physical properties.

[0124] Example 12 A thermoplastic elastomer foam material, preparation and replacement method

[0125] A thermoplastic elastomer foam material is prepared from the following components:

[0126] Thermoplastic polyamide elastomer TPAE (SGD 20012): 87.5 parts;

[0127] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0128] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0129] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0130] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0131] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0132] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 8 days to obtain a TPAE foaming material with stable physical properties.

[0133] Comparative Example 1 is a foamed material prepared by a conventional process without adding fibers and without using a replacement process.

[0134] It is prepared from the following components:

[0135] Thermoplastic polyamide elastomer TPAE (SGD 20012): 87.5 parts;

[0136] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0137] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0138] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0139] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0140] Comparative Example 2 is a foamed material prepared by conventional process without adding fiber.

[0141] It is prepared from the following components:

[0142] Thermoplastic polyamide elastomer TPAE (SGD 20012): 87.5 parts;

[0143] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0144] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0145] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0146] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0147] 3. The obtained foaming material is placed in a displacement reactor, the reactor is closed, gas is introduced, the pressure is increased to 3 MPa, and the reactor is opened after immersion for 5 days to obtain a TPAE foaming material with stable physical properties.

[0148] Comparative Example 3 is a foamed material prepared by a conventional process without using a replacement process.

[0149] It is prepared from the following components:

[0150] Thermoplastic polyamide elastomer TPAE (SGD 20012): 87.5 parts;

[0151] Antioxidant (antioxidant 944): 2.5 parts by weight;

[0152] Fiber (alkali-free glass fiber modified by silane coupling agent): 10 parts by weight

[0153] The thermoplastic elastomer foam material production method and replacement treatment thereof are as follows:

[0154] 1. Accurately weigh various materials according to the above formula, add various raw materials and processing aids into a high-speed mixer and stir for 8 minutes. After mixing evenly, use a single-screw extruder to extrude to obtain TPAE sheets.

[0155] 2. The obtained TPAE sheet was placed into a compression foaming machine with a thickness of 12 mm. CO2 supercritical fluid was introduced and infiltrated for 4 hours at 140°C and 11 MPa. The foamed material was obtained after rapid pressure release and foaming at a rate of 30 MPa / s.

[0156] Table 1 shows the immediate physical properties of the foamed material after pressure relief foaming.

[0157]

[0158] Table 2 shows the physical properties of the foamed material after five days of pressure release foaming.

[0159]

[0160]

[0161] It can be seen that the tensile strength, shear strength and compressive strength of the material after adding fibers are significantly increased, and become larger with the increase of fiber addition. And the addition of fibers does not affect other performance indicators of the material, and the surface of the material is smooth and crack-free.

[0162] Compared with the foamed product just made by pressure relief foaming, the foamed material treated by the replacement process has a significantly smaller change in hardness and density after being stored in the air for the same period of time, and its material stability is improved;

[0163] As the displacement pressure increases, the changes in hardness and density of the foamed material after the displacement process are significantly reduced after being stored in the air for the same period of time compared to the foamed product just made by pressure relief foaming, and its material stability is improved;

[0164] As time goes by, the changes in physical and chemical indicators such as density and hardness decrease, until the time is no less than the saturation time required for a specific material under a specific displacement pressure, and the changes in density and hardness no longer decrease with time.

[0165] The above description is merely an implementation case of the present invention so that professionals in the field can implement or use the present invention. It does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiments based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A thermoplastic elastomer foam material, characterized in that: The invention is prepared from raw materials including the following components: 75-100 parts of thermoplastic elastomer, 0.05-5 parts of antioxidant and 0.5-25 parts of fiber.

2. The thermoplastic elastomer foam material according to claim 1, characterized in that: The fiber is alkali-free glass fiber modified by a silane coupling agent, and the diameter of the fiber is 8-15 microns.

3. The thermoplastic elastomer foam material according to claim 1, characterized in that: The thermoplastic elastomer includes one of thermoplastic polyurethane (TPU), polyolefin elastomer (POE) and thermoplastic polyamide elastomer (TPAE).

4. The thermoplastic elastomer foam material according to claim 1, characterized in that: The antioxidant is one of antioxidant 168, antioxidant 944, antioxidant 327 and antioxidant 1098.

5. The thermoplastic elastomer foam material according to claim 1, characterized in that: The foaming material is obtained by introducing a supercritical fluid into a molding foaming machine, and then rapidly releasing the pressure after being immersed for a certain period of time.

6. The thermoplastic elastomer foam material according to claim 5, characterized in that: The supercritical fluid is CO2.

7. A method for preparing a thermoplastic elastomer foam material, characterized in that: The following steps are involved: S1. Weigh 75-100 parts by weight of thermoplastic elastomer, 0.05-5 parts by weight of antioxidant, and 0.5 to 25 parts by weight of fiber, add them into a high-speed mixer and stir for 2-10 minutes to mix evenly to obtain a mixed raw material. S2. Feed the mixed material into a single screw extruder, set the front zone temperature to 120-200°C, the die head to 140-200°C; the single screw speed to 10-30rpm, the melt pump speed to 0.5-2.5rpm, and extrude a sheet from the die head. S3. Put the obtained elastic sheet into a molding foaming machine, introduce supercritical fluid, soak it at 100-200°C and 7-20MPa for 2-8 hours, and obtain a foamed material after rapid pressure relief and foaming.

8. A method for replacing a thermoplastic elastomer foam material, characterized in that: The following steps are involved: S1. The foaming material is placed in a displacement reaction kettle, gas is introduced into the kettle, and the reaction kettle is immersed for 2-11 days at a pressure of 0.3-10 MPa. The kettle is opened to obtain a thermoplastic elastomer with high mechanical strength and stable physical properties in air.

9. A method for replacing a thermoplastic elastomer foam material according to claim 8, characterized in that: In step S1, the gas is N2 or air, or N2 first and then air.

10. The thermoplastic elastomer foam material according to any one of claims 1 to 9, characterized in that: The thermoplastic elastomer foam material has a tensile strength of more than 3.8 MPa, a shear strength of more than 3.02 MPa, and a compressive strength of more than 2.63 MPa, and a change in hardness is less than or equal to 10C after sufficient replacement.

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