An epoxy cross-linked nylon elastomer foaming material and its preparation method

Abstract

The present invention discloses an epoxy cross-linked nylon elastomer foaming material and a preparation method thereof, belonging to the technical field of foaming material preparation. The above-mentioned foaming material is prepared from the following raw materials: nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and additives. The mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and additives is 100:0.5-5:0.5-5:0.2-6:0.4-8. The epoxy cross-linked nylon elastomer foaming material prepared by the present invention has the advantages of good cold resistance, high toughness, good resilience, light weight, good mechanical properties, etc., and can be widely used as the foamed midsole of shoes.

Description

Technical Field

[0001] The present invention relates to the technical field of foam material preparation, and particularly to an epoxy cross-linked nylon elastomer foam material and a preparation method thereof. Background Art

[0002] Nylon elastomer, also known as thermoplastic polyamide elastomer, is a type of linear block polymer prepared by copolymerization of hard and soft segments. Nylon elastomers have both rubber and plastic properties. The hard segments provide physical cross-linking points, endowing the nylon elastomer with excellent mechanical properties, and the soft segments provide the required elasticity. TPAEs with different ratios of hard and soft segments can meet different usage environments and can be widely used in many fields such as automobiles, aerospace, sports equipment, cold chain transportation, medical devices, electronic appliances, etc. Especially in the field of footwear products, nylon elastomers are widely used in foamed midsoles and sole support components due to their excellent cold resistance, toughness and lighter weight.

[0003] Currently, nylon elastomer foam materials can only be processed by the supercritical method, which has high requirements for processing equipment, increasing production costs to a certain extent. And the foamed products are usually in the form of beads, which are not suitable as foamed midsoles for shoes. Chemical foaming has lower requirements for equipment and has certain advantages in production costs. However, due to the low melt strength of nylon elastomers, it is very difficult to carry out chemical foaming on nylon elastomers. Therefore, it is very necessary to break through the bottleneck of the difficulty of chemical foaming of nylon elastomers. Summary of the Invention

[0004] To solve the problems in the prior art such as the complex foaming and molding process of nylon elastomers and the difficulty of chemical foaming, the present invention provides an epoxy cross-linked nylon elastomer foam material and a preparation method thereof. In the present invention, pure nylon elastomer is modified with an epoxy cross-linking agent and foamed by a compression chemical foaming process to prepare a foam material with excellent cold resistance, toughness and resilience.

[0005] To solve the above technical problems, the present invention provides the following technical solutions:

[0006] On the one hand, the present invention provides an epoxy cross-linked nylon elastomer foaming material, which is prepared from the following raw materials: nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent. The mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent is 100: 0.5-5: 0.5-5: 0.2-6: 0.4-8. Preferably, the mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent is 100: 0.5-4: 0.5-3: 0.8-6: 1-5; more preferably, the mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent is 100: 0.8-3: 1.3-1.9: 1.5-6: 2-5. By setting the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent within the above dosage ranges, the present invention successfully prepares an epoxy cross-linked nylon elastomer foam, reduces the high requirements of nylon elastomer foaming on equipment, and enables the obtained epoxy cross-linked nylon elastomer foam to have excellent toughness and resilience.

[0007] Furthermore, the nylon elastomer is a copolymeric nylon elastomer composed of a polyamide elastomer hard segment and a polyamide elastomer soft segment. Among them, the polyamide elastomer hard segment includes at least one of polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 1010, polyamide 1011, polyamide 1012, polyamide 1210, polyamide 1211, polyamide 1212, polyamide 1213, polyamide 1311, polyamide 1312, polyamide 1313; the polyamide elastomer soft segment includes at least one of polytetrahydrofuran ether, polytetrahydrofuran, polyethylene glycol, polypropylene glycol and polybutylene glycol. Preferably, the polyamide elastomer hard segment is selected from any one of polyamide 6, polyamide 12, polyamide 1012 and polyamide 1313; the polyamide elastomer soft segment is selected from any one of polyethylene glycol (molecular weight 1000-2000) and polytetrahydrofuran (molecular weight 1000-2000). The epoxy cross-linked nylon elastomer foam prepared by the present invention from the above nylon elastomer has excellent toughness, cold resistance and resilience.

[0008] Further, the epoxy crosslinking agent includes at least one of Joncryl ADR series crosslinking agents (including ADR-4300, ADR-4370, ADR-4468, ADR-4470), KL-E series crosslinking agents (including KL-E4300, KL-E4370, KL-E4370B), and AG-80 (4,4-diaminodiphenylmethane tetraglycidylamine TGDDM) from BASF; preferably any one of ADR-4370, ADR-4468, KL-E4370, AG-80, and ADR-4300. Using the above epoxy crosslinking agent can improve the rheological properties and physical and mechanical properties of the nylon elastomer foaming material, making the nylon elastomer foam easier to mold and having excellent resilience and toughness.

[0009] Further, the foaming agent is at least one of p-toluenesulfonyl semicarbazide, N,N'-dinitrosopentamethylenetetramine, azo foaming agents, and 4,4'-oxybisbenzenesulfonyl hydrazide. Preferably any one of p-toluenesulfonyl semicarbazide, N,N'-dinitrosopentamethylenetetramine, azodicarbonamide, and 4,4'-oxybisbenzenesulfonyl hydrazide. Using the above foaming agent makes the nylon elastomer easier to foam and mold, shortens the foaming time, and simplifies the foaming process.

[0010] Further, the nucleating agent is at least one of talc, mica, white carbon black, nano-montmorillonite, nano-titanium dioxide, nano-calcium carbonate, microcrystalline cellulose, carbon nanotubes, and graphene. Preferably any one of white carbon black, microcrystalline cellulose, talc, and carbon nanotubes. Using the above nucleating agent can accelerate the formation rate of the nylon elastomer foam and improve the fineness of the cell structure.

[0011] Preferably, the auxiliary agent is at least one of an activator, a cell regulator, an antioxidant, an abrasion-resistant agent, and a dyeing agent. The above activator, cell regulator, antioxidant, abrasion-resistant agent, and dyeing agent are all made of commonly used raw materials in the art. For example, the activator includes at least one of zinc compounds, metal stearates, ethylene glycol, urea, lead dititanate, and lead diphosphite; the cell regulator includes at least one of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate; the antioxidant includes at least one of antioxidant 1010, antioxidant 1076, and antioxidant 164; the abrasion-resistant agent includes abrasion-resistant silica gel, etc.; the dyeing agent includes phthalocyanine green G5319, scarlet powder 3132, etc. Adding an abrasion-resistant agent can further improve the abrasion resistance of the nylon elastomer foam without reducing its mechanical properties. Adding a cell regulator can further reduce the density of the nylon elastomer foam and improve the fineness of the cell structure.

[0012] On the other hand, the present invention also provides a preparation method of the above epoxy crosslinked nylon elastomer foaming material, including the following steps:

[0013] 1) Mix the nylon elastomer, blowing agent, nucleating agent, epoxy crosslinking agent and additives evenly through an open mill to obtain a pre-foamed sheet;

[0014] 2) Put the pre-foamed sheet into a mold for foaming to obtain a roughly foamed material;

[0015] 3) Put the roughly foamed material into the mold again for foaming to obtain an epoxy crosslinked nylon elastomer foam.

[0016] Preferably, in step 1), the roll gap of the open mill is 3 - 9 mm, the linear speed of the front roll is 7 - 18 m / min, the speed ratio is 1.0 - 1.6, and the roll temperature is 40 - 95 °C. More preferably, the roll gap of the open mill is 4 - 7 mm, the linear speed of the front roll is 9 - 15 m / min, the speed ratio is 1.2 - 1.5, and the roll temperature is 50 - 80 °C.

[0017] Preferably, in step 2), the pressure of the mold is 3 - 25 MPa, the temperature is 130 - 250 °C, the heat preservation and pressure holding time is 5 - 20 min, and the mold is evacuated after pressure holding for 1 min. More preferably, the pressure of the mold is 5 - 20 MPa, the temperature is 160 - 230 °C, the heat preservation and pressure holding time is 6 - 10 min, and the mold is evacuated after pressure holding for 1 min. Setting the above parameter ranges can make the pre-foamed sheet foam quickly and improve the foaming efficiency. The above mold can adopt a commonly used foaming mold in the art.

[0018] Preferably, in step 3), the mold maintains normal pressure, the temperature is 80 - 200 °C, and the foaming time is 6 - 80 min. More preferably, the mold maintains normal pressure, the temperature is 90 - 180 °C, and the foaming time is 9 - 50 min. Adopting the above secondary foaming process can make the roughly foamed material foam further fully, and only normal pressure is required for this step of the mold, reducing production costs and mold losses.

[0019] The end groups of the nylon elastomer are carboxyl and hydroxyl groups, and both groups can react with the epoxy groups on the epoxy crosslinking agent. The hydroxyl groups generated after the carboxyl and hydroxyl groups react with the epoxy groups respectively further react with the carboxyl groups of the nylon elastomer to form ester groups, finally achieving a certain crosslinking effect, thus being suitable for foaming. The relevant crosslinking reaction equations are shown as the following formulas (I) - (II):

[0020]

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The epoxy cross-linked nylon elastomer foam prepared by the present invention has excellent cold resistance, toughness, resilience, and is characterized by low density, uniform cell structure, and small compression deformation. Moreover, the present invention also provides a preparation method for the epoxy cross-linked nylon elastomer foam, which solves the problems of complex and unstable foaming and molding processes and difficult chemical foaming in the existing nylon elastomer foaming technology. Detailed Embodiments

[0023] To make the technical problems, technical solutions, and advantages to be solved by the present invention clearer, the following will be described in detail with reference to specific embodiments.

[0024] In the present invention, materials and reagents without special instructions can be obtained through commercial channels. For example: Nylon 6 elastomer (soft segment: polyethylene glycol 1500): purchased from Zhejiang Xinyuan Technology Co., Ltd. Nylon 12 elastomer (soft segment: polytetrahydrofuran 2000): purchased from Arkema France. Nylon 1012 elastomer (soft segment: polytetrahydrofuran 2000): purchased from Boxing Risheng Plasticization Co., Ltd. Nylon 1313 elastomer (soft segment: polytetrahydrofuran 2000): purchased from Zhejiang Xinyuan Technology Co., Ltd. ADR-4370: purchased from BASF (China) Co., Ltd. ADR-4468: purchased from BASF (China) Co., Ltd. KL-E4370: purchased from Shanxi Research Institute of Chemical Industry (Co., Ltd.). AG-80: purchased from Guangzhou Tiantai Chemistry Co., Ltd. ADR-4300: purchased from BASF (China) Co., Ltd. All components in the present invention can be purchased through commercial channels, and will not be elaborated one by one here.

[0025] The present invention provides an epoxy cross-linked nylon elastomer foaming material and its preparation method. The specific embodiments are as follows.

[0026] Example 1

[0027] A preparation method for an epoxy cross-linked nylon elastomer foaming material includes the following steps:

[0028] 1) Take 250 g of nylon 6 elastomer, 3 g of p-toluenesulfonyl semicarbazide, 4.5 g of silica, 5 g of ADR-4370, and 1 g of antioxidant 1010, and mix them on an open mill to obtain a pre-foamed sheet. The roll gap of the open mill is 3 mm, the front roll linear speed is 11 m / min, the speed ratio is 1.3, and the roll temperature is 75 °C.

[0029] 2) Put 200 g of the pre-foamed sheet into a foaming mold at 200 °C, apply a pressure of 13 MPa, start vacuuming the mold after 1 min of pressurization, and maintain it for 9 min to obtain a roughly foamed material.

[0030] 3) Put the roughly foamed material into a foaming mold at 180 °C again for secondary foaming, and keep it at normal pressure and heat preservation for 40 min to obtain the epoxy cross-linked nylon elastomer foam.

[0031] Example 2

[0032] A preparation method of an epoxy cross-linked nylon elastomer foaming material, comprising the following steps:

[0033] 1) Take 250 g of nylon 12 elastomer, 3 g of N,N′-dinitrosopentamethylenetetramine, 4.5 g of microcrystalline cellulose, 5 g of ADR-4468, 3 g of sodium dodecylbenzenesulfonate and 1 g of antioxidant 1010, and mix them on an open mill to obtain a pre-foamed sheet. The roll gap of the open mill is 5 mm, the front roll linear speed is 10 m / min, the speed ratio is 1.2, and the roll temperature is 70 °C.

[0034] 2) Put 200 g of the pre-foamed sheet into a foaming mold at 190 °C, apply a pressure of 16 MPa, start to evacuate the mold after 1 min of pressurization, and keep it for 10 min to obtain a roughly foamed material.

[0035] 3) Put the roughly foamed material into a foaming mold at 170 °C again for secondary foaming, keep it at normal pressure and heat for 30 min to obtain an epoxy cross-linked nylon elastomer foam.

[0036] Example 3

[0037] A preparation method of an epoxy cross-linked nylon elastomer foaming material, comprising the following steps:

[0038] 1) Take 250 g of nylon 1012 elastomer, 2.5 g of azodicarbonamide, 4 g of talcum powder, 5 g of KL-E4370, 2 g of ethylene glycol, 2 g of lead metatitanate and 1 g of antioxidant 1010, and mix them on an open mill to obtain a pre-foamed sheet. The roll gap of the open mill is 6 mm, the front roll linear speed is 12 m / min, the speed ratio is 1.3, and the roll temperature is 75 °C.

[0039] 2) Put 200 g of the pre-foamed sheet into a foaming mold at 170 °C, apply a pressure of 11 MPa, start to evacuate the mold after 1 min of pressurization, and keep it for 7 min to obtain a roughly foamed material.

[0040] 3) Put the roughly foamed material into a foaming mold at 130 °C again for secondary foaming, keep it at normal pressure and heat for 30 min to obtain an epoxy cross-linked nylon elastomer foam.

[0041] Example 4

[0042] A preparation method of an epoxy cross-linked nylon elastomer foaming material, comprising the following steps:

[0043] 1) Take 250 g of nylon 1313 elastomer, 2.5 g of 4,4′-oxybis(benzenesulfonyl hydrazide), 4 g of carbon nanotubes, 5 g of AG-80, 3 g of lead phosphite, 1 g of antioxidant 1010, and 2 g of wear-resistant agent silica gel, and mix them on an open mill to obtain a pre-foamed sheet. The roll gap of the open mill is 4 mm, the linear speed of the front roll is 11 m / min, the speed ratio is 1.3, and the roll temperature is 70 °C.

[0044] 2) Put 200 g of the pre-foamed sheet into a foaming mold at 160 °C, apply a pressure of 13 MPa, start evacuating the mold after 1 minute of pressurization, and maintain for 10 minutes to obtain a roughly foamed material.

[0045] 3) Put the roughly foamed material into a foaming mold at 140 °C again for secondary foaming, keep it at normal pressure and heat-insulate for 40 minutes to obtain an epoxy cross-linked nylon elastomer foam.

[0046] Example 5

[0047] A preparation method of an epoxy cross-linked nylon elastomer foaming material, comprising the following steps:

[0048] 1) Take 250 g of nylon 6 elastomer, 1 g of azodicarbonamide, 2 g of 4,4′-oxybis(benzenesulfonyl hydrazide), 1.5 g of nano-titanium dioxide, 0.5 g of nano-calcium carbonate, 3 g of ADR-4300, 2 g of KL-E4370, 7 g of ethylene glycol, 6 g of sodium lauryl sulfate, 4 g of zinc stearate, and 3 g of antioxidant 1010, and mix them on an open mill to obtain a pre-foamed sheet. The roll gap of the open mill is 7 mm, the linear speed of the front roll is 9 m / min, the speed ratio is 1.3, and the roll temperature is 50 °C.

[0049] 2) Put 200 g of the pre-foamed sheet into a foaming mold at 170 °C, apply a pressure of 5 MPa, start evacuating the mold after 1 minute of pressurization, and maintain for 8 minutes to obtain a roughly foamed material.

[0050] 3) Put the roughly foamed material into a foaming mold at 100 °C again for secondary foaming, keep it at normal pressure and heat-insulate for 50 minutes to obtain an epoxy cross-linked nylon elastomer foam.

[0051] To further illustrate the beneficial effects of this application, due to limited space, only Example 3 is taken as an example to construct the following comparative examples.

[0052] Comparative Example 1

[0053] In this comparative example, the epoxy cross-linking agent is replaced with an equal amount of ditert-butyl peroxyisopropylbenzene, and the other conditions are the same as those in Example 3.

[0054] Comparative Example 2

[0055] A preparation method of a nylon elastomer foaming material, comprising the following steps:

[0056] (1) Take 250 g of nylon 1012 elastomer, 4 g of talcum powder, 5 g of KL-E4370, 2 g of zinc oxide, 2 g of zinc stearate, and 1 g of antioxidant 1010.

[0057] (2) Premix the weighed raw materials and then melt and knead them in an extruder at 200 °C for 5 min. After extrusion, cut the pellets underwater at 25 °C to obtain thermoplastic elastomer pre-foamed particles. Then preheat the obtained thermoplastic elastomer pre-foamed particles to 160 °C and pour them into a high-temperature resistant midsole mold preheated to 160 °C. After closing the mold, introduce carbon dioxide gas into the container to make the pressure reach 20 MPa, and let the gas in the supercritical state impregnate and saturate the thermoplastic elastomer pre-foamed particles for 25 min. Then quickly release the pressure (pressure release rate: 15 MPa / s) and open the mold, and cool at room temperature to obtain the composite material.

[0058] Comparative Example 3

[0059] In this comparative example, the mass ratio of nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent, and auxiliary agent is 100:6:1.6:2:2, and the other conditions are the same as those in Example 3.

[0060] Comparative Example 4

[0061] In this comparative example, the mass ratio of nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent, and auxiliary agent is 100:1:5.5:2:2, and the other conditions are the same as those in Example 3.

[0062] Comparative Example 5

[0063] In this comparative example, the mass ratio of nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent, and auxiliary agent is 100:1:1.6:2:9, and the other conditions are the same as those in Example 3.

[0064] Perform performance tests on the foamed materials prepared in the above Examples 1-5 and Comparative Examples 1-5. Among them, the density and pore size are tested according to "GB / T 533-2008 Determination of the Density of Vulcanized Rubber or Thermoplastic Rubber"; the resilience is tested according to "GB / T 10652-2001 Determination of the Resilience of High Polymer Porous Elastic Materials"; the toughness is tested according to "GB / T 528-2009 Determination of the Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the foam melt strength is tested according to "GB / T 3682-2000 Determination of the Melt Mass-Flow Rate and Melt Volume-Flow Rate of Thermoplastics"; the cold resistance is tested according to "ASTM D1052-2009"; the compression set is tested according to "HG / T2876-2009", and the test results are shown in Tables 1-2.

[0065] Table 1

[0066]

[0067] As can be seen from Table 1, the epoxy cross-linked nylon elastomer foam prepared by the present invention has a low density, excellent resilience and cold resistance, and a small compression deformation. At the same time, the high elongation at break proves its good toughness and can be widely used as a foamed midsole for shoes.

[0068] Table 2

[0069]

[0070] As can be seen from Table 2, compared with the existing EVA foamed material (Comparative Example 1), the nylon elastomer foamed material of the present invention not only has a small density, high resilience and large elongation at break, but also has excellent cold resistance and compression deformation ability; compared with the method for preparing nylon elastomer foamed material by supercritical fluid (Comparative Example 2), the preparation method of the present invention has improved performance in all other aspects except that the density difference is not significant, and it also has the advantages of simple preparation method.

[0071] At the same time, when the amounts of the foaming agent (Comparative Example 3), nucleating agent (Comparative Example 4) and auxiliary agent (Comparative Example 5) are adjusted, the foamed materials prepared have deteriorated resilience, elongation at break and compression deformation performance, and the cold resistance also deteriorates. This is because the specific ratio between the nylon elastomer, foaming agent, nucleating agent, epoxy cross-linking agent and auxiliary agent of the present invention can obtain a foamed material with stable foaming molding, making it have excellent toughness, cold resistance, resilience, and properties such as small density, uniform cell structure and small compression deformation.

[0072] In summary, the present invention not only successfully prepares an epoxy cross-linked nylon elastomer foam material by a simple method, but also makes the prepared material have excellent cold resistance, toughness and resilience, and also has a small density, uniform cell structure and small compression deformation.

[0073] The above is the preferred embodiment of the present invention. For those of ordinary skill in the art, without departing from the principle of the present invention, making several improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. An epoxy cross-linked nylon elastomer foaming material, characterized in that, It is prepared from the following raw materials: nylon elastomer, foaming agent, nucleating agent, epoxy crosslinking agent and auxiliary agent, and the mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy crosslinking agent and auxiliary agent is 100: 0.5-5: 0.5-5: 0.2-6: 0.4-8; The nylon elastomer is a copolymer nylon elastomer composed of a polyamide elastomer hard segment and a polyamide elastomer soft segment. Among them, the polyamide elastomer hard segment is polyamide 6, polyamide 12, polyamide 1012 or polyamide 1313; the polyamide elastomer soft segment is polytetrahydrofuran or polyethylene glycol; The preparation method of the above epoxy crosslinked nylon elastomer foaming material includes the following steps: 1) Mix the nylon elastomer, foaming agent, nucleating agent, epoxy crosslinking agent and auxiliary agent evenly through an open mill to obtain a pre-foamed sheet; the roll gap of the open mill is 3-9 mm, the front roll linear speed is 7-18 m / min, the speed ratio is 1.0-1.6, and the roll temperature is 40-95 °C; 2) Put the pre-foamed sheet into a mold for foaming to obtain a roughly foamed material; the pressure of the mold is 3-25 MPa, the temperature is 130-250 °C, the heat preservation and pressure holding time is 5-20 min, and the mold is evacuated 1 min after pressure holding; 3) Put the roughly foamed material into the mold again for foaming to obtain an epoxy crosslinked nylon elastomer foam; the mold is kept at normal pressure, the temperature is 80-200 °C, and the foaming time is 6-80 min.

2. The epoxy cross-linked nylon elastomer foamed material according to claim 1, characterized in that, The mass ratio of the nylon elastomer, foaming agent, nucleating agent, epoxy crosslinking agent and auxiliary agent is 100: 0.5-4: 0.5-3: 0.8-6: 1-5.

3. The epoxy crosslinked nylon elastomer foamed material according to claim 2, wherein The epoxy crosslinking agent is at least one of Joncryl ADR-4300, Joncryl ADR-4370, Joncryl ADR-4468, Joncryl ADR-4470, KL-E4300, KL-E4370, KL-E4370B, AG-80.

4. The epoxy crosslinked nylon elastomer foamed material according to claim 3, wherein The foaming agent is at least one of p-toluenesulfonyl semicarbazide, N,N'-dinitrosopentamethylenetetramine, azo foaming agent and 4,4'-oxybisbenzenesulfonyl hydrazide.

5. The epoxy crosslinked nylon elastomer foamed material according to claim 4, characterized in that, The nucleating agent is at least one of talc, mica, white carbon black, nano-montmorillonite, nano-titanium dioxide, nano-calcium carbonate, microcrystalline cellulose, carbon nanotubes, graphene.

6. The epoxy crosslinked nylon elastomer foamed material according to claim 5, characterized in that, The auxiliary agent is at least one of activator, cell structure regulator, antioxidant, wear-resistant agent, dyeing agent.

7. The epoxy crosslinked nylon elastomer foaming material according to claim 6, wherein The preparation method of the epoxy crosslinked nylon elastomer foaming material includes the following steps: 1) Take 250 g of nylon 1012 elastomer, 2.5 g of azodicarbonamide, 4 g of talc, 5 g of KL-E4370, 2 g of ethylene glycol, 2 g of lead titanate and 1 g of antioxidant 1010, and mix them on an open mill to obtain a pre-foamed sheet; among them, the roll gap of the open mill is 6 mm, the front roll linear speed is 12 m / min, the speed ratio is 1.3, and the roll temperature is 75 °C; 2) Put 200 g of pre-expanded sheet into a foaming mold at 170 °C, apply a pressure of 11 MPa. After applying the pressure for 1 minute, start evacuating the mold and maintain it for 7 minutes to obtain a roughly foamed material; 3) Put the roughly foamed material into a foaming mold at 130 °C again for secondary foaming, keep it at normal pressure and heat-insulate for 30 minutes to obtain an epoxy cross-linked nylon elastomer foam.

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