A composite elastomeric material and a method of making and use thereof

Abstract

This invention relates to a composite elastomer material, its preparation method, and its uses. The composite elastomer material comprises a lattice-structured elastomer and an elastic resin layer, wherein the elastic resin layer is formed at least within the internal pores of the lattice-structured elastomer and bonded to the lattice-structured elastomer. Further, the elastic resin layer is also formed on the outer surface of the lattice-structured elastomer. The composite elastomer material is prepared by fully contacting the lattice-structured elastomer with a treatment liquid containing elastic resin or a raw material forming the elastic resin and a resin curing agent, followed by heating and curing. The composite elastomer material prepared by this invention is lightweight and exhibits excellent compression resistance.

Description

Technical Field

[0001] This invention relates to a composite elastomer material, its preparation method, and its uses. Background Technology

[0002] In many applications requiring cushioning and support, such as sports, packaging, and protection, high-strength, high-elasticity (compression resistance), high-impact resistance, and lightweight elastomer materials are needed. Currently, elastomers made from thermoplastic powders via 3D printing are widely used in these applications due to their advantages, including simple molding process, environmental friendliness, high material utilization, recyclability, and high precision. However, 3D-printed elastomers suffer from insufficient mechanical properties, especially compressive strength, due to factors such as melt shrinkage, weak bonding between powder particles, and numerous voids. To achieve the required compression resistance, the elastomer thickness must be increased, leading to undesirable increases in volume, weight, and cost. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a composite elastomer material that is not only lightweight but also has excellent compression resistance, in order to address the shortcomings and deficiencies of the prior art.

[0004] To solve the above technical problems, the present invention adopts the following technical solution:

[0005] A composite elastomer material comprising a lattice structure elastomer and an elastic resin layer, wherein the elastic resin layer is formed at least in the internal pores of the lattice structure elastomer and bonded to the lattice structure elastomer.

[0006] Furthermore, the elastic resin layer is also formed on the outer surface of the lattice structure elastomer, thereby making the composite elastomer material more aesthetically pleasing.

[0007] In some embodiments of the present invention, the composite elastomer material is prepared by fully contacting the lattice structure elastomer with a treatment liquid containing elastic resin or raw materials for forming elastic resin and resin curing agent, and then heating and curing it.

[0008] In some embodiments of the present invention, the lattice structure elastomer is a thermoplastic elastomer.

[0009] In some embodiments of the present invention, the elastic resin constituting the elastic resin layer has a hardness of 50A Shore A or higher and 40D Shore A or lower, a viscosity of less than 12000 cP at 25°C, a tensile strength of 5 MPa or higher, and an elongation at break of 120% or higher.

[0010] In some embodiments of the present invention, the resin constituting the thermoplastic elastomer is selected from one or a combination of two of thermoplastic polyurethane resin and thermoplastic polyethylene resin.

[0011] In some embodiments of the present invention, the elastic resin constituting the elastic resin layer is one or more selected from polyurethane resin, acrylic resin, and silicone resin.

[0012] Through research, the inventors discovered that by fully contacting the lattice-structured elastomer with a treatment liquid containing elastic resin or raw materials for forming elastic resin and a resin curing agent, and then heating and curing it, the elastic resin forms an elastic resin layer in the internal pores and on the outer surface of the lattice-structured elastomer. The elastic resin cures, bonds, and composites with the lattice-structured elastomer, filling the internal pores and thus obtaining a composite elastomer material with excellent mechanical properties. At the same weight, this composite elastomer material exhibits higher compressive strength; and under the same compressive strength conditions, the material has a lower weight. Furthermore, the elastic resin layer on the outer surface of the lattice-structured elastomer can reduce the surface roughness of the material, resulting in a smooth surface for the composite elastomer material.

[0013] In some embodiments of the present invention, the mass of the elastic resin layer is 10%-90% of the mass of the lattice structure elastomer.

[0014] More preferably, the mass of the elastic resin layer is 20% to 60% of the mass of the lattice structure elastomer.

[0015] In some specific embodiments, the porosity of the lattice structure elastomer is 5% to 40%.

[0016] In some specific embodiments, the lattice structure elastomer is prepared by 3D printing.

[0017] In some specific embodiments, the density of the composite elastomer material is 0.7-1.1 g / cm³. 3 Furthermore, the pressure required to compress to 50% of its deformation is greater than 200 N. This demonstrates that the composite elastomer material of this application achieves both lightweight properties and excellent compressive strength.

[0018] The present invention further provides a method for preparing the above-mentioned composite elastomer material, the method comprising: a step of coating the lattice structure elastomer with a treatment liquid containing the elastic resin or its raw material and a curing agent, and a step of heating the lattice structure elastomer to cure and bond the elastic resin therein to the lattice structure elastomer.

[0019] In some specific embodiments, the coating process is carried out by spraying, dipping, or electroplating, and during the coating process, the treatment liquid is allowed to penetrate into the internal pores of the lattice structure elastomer.

[0020] In some specific embodiments, the coating treatment takes 5-20 minutes, and the heat treatment takes 3-12 hours.

[0021] Further, the mass concentration of the elastic resin in the treatment solution is 30-60%, and the mass concentration of the curing agent is 1%-10%. In some specific embodiments, the mass concentration of the elastic resin in the treatment solution is 40-55%, and the mass concentration of the curing agent is 2%-5%.

[0022] In some specific embodiments, the heat curing is carried out at a temperature of 80 to 100°C, and the coating treatment and heat curing are performed once, or repeated 1 to 3 times after one treatment.

[0023] In some specific embodiments, the treatment liquid contains pigments and / or fillers. Fillers can increase the strength of the composite elastomer material, and pigments can achieve the coloring of the material.

[0024] Preferably, the mass of the pigment is 0.01-1% of the mass of the elastic resin.

[0025] Furthermore, the method also includes a step of 3D printing a lattice structure elastomer using a powder sintering process, wherein the sintering density and porosity of the lattice structure elastomer are determined based on the compressive strength and density to be achieved by the composite material, and then parameters including 3D printing temperature and laser energy are set based on the sintering density and porosity of the lattice structure elastomer.

[0026] In some specific implementations, the following parameters are used: temperature 80-140℃, laser power 30-100W, scanning rate 4000-15000mm / s, and scanning spacing 0.1-0.3mm.

[0027] In some specific implementations, different curing agents are selected depending on the resin.

[0028] By adjusting parameters such as 3D printing temperature and laser energy, the sintering density and porosity of lattice structure elastomers can be controlled, thereby controlling the depth and quality of elastic resin penetration. The lower the temperature and laser power, the higher the porosity of the printed lattice structure elastomer, the higher the content of elastic resin in the composite elastomer material, and the better the compressive strength of the composite elastomer material.

[0029] According to the present invention, there are no particular limitations on the lattice cell structure constituting the lattice structure elastomer. The lattice cell structure can be common cubes, stars, octagons, hexagons, rhombuses, and tetrahedrons, etc.

[0030] In some specific embodiments, the lattice cell structure of the lattice structure elastomer is a rhombic dodecahedron.

[0031] The present invention further provides the use of the above-mentioned composite elastomer material in cushioning or support products.

[0032] Furthermore, the cushioning or support products include protective gear, packaging materials, cushioning pads, and shoe midsoles.

[0033] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0034] This invention utilizes a composite lattice structure elastomer and an elastic resin coating. The elastic resin penetrates into the internal pores of the lattice structure elastomer, creating a tight bond between the two. Unexpectedly, without compromising the inherent advantages of the lattice structure elastomer, the compressive strength of the material is significantly improved, while the volume remains unchanged and the weight increases only slightly. Compared to lattice structure elastomers without the elastic resin coating, the composite elastomer of this invention has a significantly smaller volume and lighter weight to achieve the same compressive strength; and at the same weight, the composite elastomer of this invention exhibits significantly higher compressive strength.

[0035] The composite elastomer material preparation process of this invention employs 3D printing to prepare a lattice-structured elastomer, followed by coating and curing processes. On one hand, by adjusting parameters such as 3D printing temperature and laser power, the sintering density and porosity of the lattice-structured elastomer can be controlled, thereby controlling the depth and quality of elastic resin penetration, and ultimately the degree of improvement in the compressive properties of the composite elastomer material. Therefore, composite elastomer materials with various properties can be flexibly prepared to meet the personalized needs of various application scenarios. On the other hand, the coating and curing processes ensure a more complete and tighter bond between the lattice-structured elastomer and the elastic resin coating, contributing to improved material strength and service life. Attached Figure Description

[0036] Figure 1 These are photographs of the lattice structure elastomer and composite elastomer materials prepared in Example 1;

[0037] Figure 2 An optical micrograph of the composite elastomer material prepared in Example 1;

[0038] Figure 3 Photographs of TPU tensile specimens treated with acrylic resin for Comparative Example 1;

[0039] Figure 4 A photograph of the sample prepared according to Comparative Example 3. Detailed Implementation

[0040] The technical solutions of the present invention will be described in detail below with reference to specific embodiments, so that those skilled in the art can better understand and implement the technical solutions of the present invention, but the present invention is not limited to the scope of the examples described.

[0041] Example 1

[0042] This example provides a composite elastomer material, which is prepared through the following steps:

[0043] 1) Using thermoplastic polyurethane (TPU) as raw material, a lattice structure elastomer is 3D printed by powder sintering. Its lattice cell structure is a rhombic dodecahedron. The process parameters are: main temperature 100-120℃, laser power 55W, scanning rate 4000-10000mm / s, and scanning spacing 0.3mm.

[0044] 2) Mix 95 parts by weight of a commercially available polyurethane resin solution with a mass concentration of approximately 45% and 5 parts by weight of an isocyanate curing agent using a high-speed stirrer to obtain an impregnation treatment solution. The polyurethane resin has a hardness of 80A, a viscosity of 3000 cP at 25°C, a tensile strength of 8 MPa, and an elongation at break of 245%.

[0045] 3) Immerse the printed lattice structure elastomer in the impregnation solution prepared in step 2) for 10 minutes, remove it and spin dry, then place it in an 80℃ vacuum oven for 3 hours to cure, and obtain the composite material sample.

[0046] The sintering density and porosity of the lattice structure elastomers obtained at different scanning rates, as well as the weight of the lattice structure elastomers before and after polyurethane resin treatment, and the pressure at 50% compression deformation are shown in Table 1 below:

[0047] Table 1

[0048]

[0049]

[0050] As shown in Table 1 above, by controlling the process parameters of 3D printing, the sintering density and porosity of the lattice structure elastomer can be adjusted. The greater the porosity, the higher the content of polyurethane resin in the composite elastomer material, and the greater the improvement in the compressive strength of the composite elastomer material.

[0051] Figure 1The images show the lattice structure elastomer obtained at a scanning rate of 4000 mm / s before and after treatment with polyurethane resin. It can be seen that after treatment, the polyurethane resin is located in the internal pores and on the outer surface of the lattice structure elastomer.

[0052] Figure 2 The image shows a micrograph of the lattice structure elastomer obtained at a scanning rate of 4000 mm / s after being treated with polyurethane resin. It can be seen that the polyurethane resin can penetrate into the lattice structure elastomer and bond tightly with the matrix lattice structure elastomer.

[0053] Example 2

[0054] This example provides a composite elastomer material whose preparation process is basically the same as that of Example 1, wherein the scanning rate is 4000 mm / s. The only difference is that 0.1 parts by mass of pigments are added in step 2), wherein the pigments are red pigment, purple pigment, green pigment and yellow pigment, respectively, and red, purple, green and yellow composite elastomer materials are obtained accordingly.

[0055] Example 3

[0056] This example provides a composite elastomer material, which is prepared through the following steps:

[0057] 1) Using thermoplastic polyurethane (TPU) as raw material, a lattice structure elastomer is 3D printed by powder sintering. The process parameters are: main temperature 100-120℃, laser power 55W, scanning rate 4000mm / s, and scanning spacing 0.3mm.

[0058] 2) Mix 55 parts by weight of a commercially available polyurethane resin solution (same as in Example 1), 5 parts by weight of an isocyanate curing agent, and 40 parts by weight of a mixed solvent of esters and alcohols as a diluent, and disperse them evenly using a high-speed stirrer to obtain an impregnation treatment solution. The type of polyurethane resin is the same as in Example 1.

[0059] 3) Immerse the printed lattice structure elastomer in the impregnation solution for 10 minutes, remove it and spin dry, then place it in an 80℃ vacuum oven for 3 hours to cure.

[0060] 4) Place the cured sample back into the impregnation solution, immerse for 10 minutes, spin dry, and cure. Repeat 1-3 times to obtain composite elastomer material samples with one or more layers of polyurethane resin. The sample properties are listed in Table 2 below.

[0061] Table 2

[0062]

[0063] As can be seen from Table 2 above, repeated impregnation and curing of polyurethane resin can increase the amount of polyurethane resin in the composite elastomer material, resulting in a higher compressive strength.

[0064] Example 4

[0065] This example provides a method for preparing a composite elastomer material, as detailed below:

[0066] 1) Using thermoplastic polyurethane (TPU) as raw material, a lattice structure elastomer is 3D printed by powder sintering. The process parameters are: main temperature 100-120℃, laser power 55W, scanning rate 4000mm / s, and scanning spacing 0.3mm.

[0067] 2) Mix 98 parts by weight of a commercially available acrylic resin solution with a mass concentration of approximately 55% and 2 parts by weight of curing agent 4,4'-methylenebis(2-methylcyclohexylamine) evenly with a high-speed stirrer to obtain an impregnation treatment solution. The acrylic resin has a hardness of 68A, a viscosity of 6000 cP at 25°C, a tensile strength of 12 MPa, and an elongation at break of 200%.

[0068] 3) Immerse the printed TPU lattice structure elastomer in the impregnation solution for 10 minutes, remove it and spin dry, then place it in an 80℃ vacuum oven for 10 hours to cure, and obtain the composite elastomer material sample.

[0069] After step 3), the weight of the material increased from 22.33 g to 32.72 g, and the pressure at 50% compressive deformation increased from 222.1 N to 589.2 N. The density of the prepared composite elastomer material was 0.993 g / cm³. 3 .

[0070] Comparative Example 1

[0071] 1) Using thermoplastic polyurethane (TPU) as raw material, TPU tensile strips are 3D printed by powder sintering. The process parameters are: main temperature 100-120℃, laser power 55W, scanning rate 4000mm / s, and scanning spacing 0.3mm.

[0072] 2) 98 parts by weight of commercially available acrylic resin solution (same as in Example 4) and 2 parts by weight of curing agent 4,4'-methylenebis(2-methylcyclohexylamine) were mixed and dispersed evenly using a high-speed stirrer to obtain an acrylic resin solution for treatment. The acrylic resin solution was the same as that in Example 4.

[0073] 3) Immerse the printed TPU stretching strip in the acrylic resin solution for 10 minutes, remove it and spin dry, then place it in an 80℃ vacuum oven for 10 hours to cure, and obtain the composite elastomer material sample.

[0074] Table 3 lists the sample weights and properties before and after treatment. Photographs of the TPU tensile specimens after treatment with acrylic resin solution are shown below. Figure 3 As shown, the acrylic resin forms a coating only on the outer surface of the stretched specimen.

[0075] Comparative Example 2

[0076] 1) Using thermoplastic polyurethane (TPU) as raw material, a polyurethane printed part with a porosity of 30% was produced by powder sintering 3D printing. The pores of the printed part are irregular and most of them are closed-cell structures.

[0077] 2) Mix 95 parts by weight of polyurethane resin solution and 5 parts by weight of isocyanate curing agent with a high-speed stirrer to obtain a polyurethane resin solution for treatment. The polyurethane resin solution and curing agent are the same as those in Example 1.

[0078] 3) Immerse the printed polyurethane material in a polyurethane solution for 10 minutes, remove it and spin dry, then place it in an 80℃ vacuum oven to cure for 3 hours to obtain a composite elastomer material sample.

[0079] The sample weights and properties before and after treatment are listed in Table 3.

[0080] Table 3

[0081]

[0082]

[0083] As shown in Table 3 above, when the substrate in the composite material is not a lattice structure elastomer, but a regular tensile strip or a polyurethane resin with an irregular pore structure, even if polyurethane resin impregnation treatment is performed, the compressive strength of the material cannot be improved.

[0084] Comparative Example 3

[0085] This example provides a method for preparing a composite material, which is basically the same as in Example 1, except that the scanning rate is 4000 mm / s. The only difference is that in step 2), a commercially available epoxy resin solution is used instead of a polyurethane resin solution, and an amine curing agent is used instead of an isocyanate curing agent. The epoxy resin has a hardness of 85D, a tensile strength of 45 MPa, and an elongation at break of 59%. Figure 4 The photographs of the obtained composite materials show that after epoxy resin impregnation, the performance of the lattice structure elastomer was not improved; instead, it lost its elasticity, its strength decreased, and it became easy to break.

[0086] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0087] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A composite elastomer material, characterized in that: The composite elastomer material includes a lattice structure elastomer and an elastic resin layer, wherein the elastic resin layer is formed at least in the internal pores of the lattice structure elastomer and is bonded to the lattice structure elastomer. The lattice cell structure of the lattice structured elastomer is a rhombic dodecahedron. The composite elastomer material is prepared by fully contacting the lattice structure elastomer with a treatment liquid containing elastic resin or raw materials that form elastic resin and resin curing agent, and then heating and curing it. The lattice structure elastomer is a thermoplastic elastomer; The resin constituting the thermoplastic elastomer is selected from thermoplastic polyurethane resin; The elastic resin constituting the elastic resin layer is selected from acrylic resin; The mass of the elastic resin layer is 10% to 90% of the mass of the lattice structure elastomer; The porosity of the lattice structure elastomer is 5% to 40%.

2. The composite elastomer material according to claim 1, characterized in that: The elastic resin layer is also formed on the outer surface of the lattice structure elastomer.

3. The composite elastomer material according to claim 1, characterized in that: The elastic resin constituting the elastic resin layer has a hardness of 50A Shore A or higher and 40D Shore A or lower, a viscosity of less than 12000 cP at 25°C, a tensile strength of 5MPa or higher, and an elongation at break of 120% or higher.

4. The composite elastomer material according to claim 1, characterized in that: The mass of the elastic resin layer is 20% to 60% of the mass of the lattice structure elastomer.

5. The composite elastomer material according to claim 1, characterized in that: The lattice structure elastomer is prepared by 3D printing.

6. The composite elastomer material according to claim 1, characterized in that: The density of the composite elastomer material is 0.7-1.1 g / cm³. 3 Meanwhile, the pressure required to compress to 50% of its deformation is greater than 200N.

7. A method for preparing the composite elastomer material according to any one of claims 1 to 6, characterized in that: The method includes: a step of coating the lattice structure elastomer with a treatment liquid containing the elastic resin or its raw materials and a curing agent, and a step of heating the lattice structure elastomer to cure and bond the elastic resin therein to the lattice structure elastomer.

8. The method according to claim 7, characterized in that: The coating process is carried out by spraying, dipping, or electroplating. During the coating process, the treatment liquid is allowed to penetrate into the internal pores of the lattice structure elastomer.

9. The method according to claim 7 or 8, characterized in that: The mass concentration of elastic resin in the treatment liquid is 30-60%, and the mass concentration of curing agent is 1%-10%. The heat curing is carried out at a temperature of 80-100℃. The coating treatment and heat curing are performed once, or after one treatment, they are repeated 1-3 times.

10. The method according to claim 7, characterized in that: The treatment solution contains pigments and / or fillers.

11. The method according to claim 7, characterized in that: The method also includes a step of 3D printing a lattice structure elastomer using a powder sintering process, wherein the sintering density and porosity of the lattice structure elastomer are determined based on the compressive strength and density to be achieved by the composite material, and then parameters including 3D printing temperature and laser energy are set based on the sintering density and porosity of the lattice structure elastomer.

12. Use of a composite elastomer material as described in any one of claims 1 to 6 in a cushioning or support product.

13. The use according to claim 12, characterized in that: The cushioning or support products include protective gear, packaging materials, cushioning pads, and shoe midsoles.

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