A novel EPE material and a preparation method thereof

Abstract

The present disclosure provides a new EPE material and a preparation method thereof, the method comprising: cold pressing on one side of an EPE raw material to cause elastic deformation of the cold-pressed side of the EPE raw material, forming a cold-pressed elastic deformation area that can be restored; hot pressing on the other side of the EPE raw material to cause plastic deformation of the hot-pressed side of the EPE raw material, forming a dense hot plastic deformation area; and a transition area between the cold-pressed elastic deformation area and the hot plastic deformation area. The new EPE material prepared by the preparation method of the present disclosure maintains the softness of the surface of the EPE itself, and the plastic deformation area has good strength and toughness. Therefore, a new EPE material with a soft surface and internal rigidity can be obtained, further widening the application range of EPE materials.

Description

Technical Field

[0001] This disclosure relates to the technical field of modified materials, and in particular to a novel EPE material and its preparation method. Background Technology

[0002] Polyethylene foam, also known as EPE pearl cotton, is a non-crosslinked closed-cell structure and a new type of environmentally friendly packaging material. It is composed of countless independent air bubbles created through the physical foaming of low-density polyethylene resin, overcoming the shortcomings of ordinary foam such as fragility, deformation, and poor resilience. Due to its numerous advantages, including water and moisture resistance, shock absorption, sound insulation, heat insulation, excellent plasticity, high toughness, recyclability, environmental friendliness, and strong impact resistance, it is widely used in the packaging of many items.

[0003] EPE is a plastic material with a density of 30 kg / m³. 3 For conventional EPE materials, plastic deformation occurs under stress exceeding 500 kPa, leading to a failure of their cushioning properties, which limits their application range to some extent. To broaden the application range of EPE materials, a new type of EPE material is needed, characterized by a soft outer surface and strong internal toughness. Summary of the Invention

[0004] This disclosure provides a novel EPE material and its preparation method, thereby at least solving the above-mentioned technical problems existing in the prior art.

[0005] According to a first aspect of this disclosure, a method for preparing a novel EPE material is provided, characterized in that the method comprises:

[0006] Cold pressing is performed on one side of the EPE raw material to cause elastic deformation on the cold-pressed side of the EPE raw material, forming a recoverable cold-pressed elastic deformation zone.

[0007] Hot pressing is performed on the other side of the EPE material to cause plastic deformation on the hot-pressed side of the EPE material, forming a dense thermoplastic deformation zone.

[0008] The transition zone is between the cold-pressed elastic deformation zone and the thermoplastic deformation zone.

[0009] In one possible implementation, the cold pressing on one side of the EPE raw material includes:

[0010] EPE raw material is conveyed by a conveyor wheel, and a cold-pressing eccentric wheel is set above the conveyor wheel. The cold-pressing eccentric wheel is used to cold-press one side of the EPE raw material. The rotation direction of the cold-pressing eccentric wheel is opposite to the rotation direction of the conveyor wheel.

[0011] In one embodiment, at least one elliptical protrusion is provided on the side wall of the cold-pressed eccentric wheel.

[0012] In one possible implementation, the hot pressing on the other side of the EPE material includes:

[0013] The hot pressing roller is located on one side of the transmission roller and is used to hot press the other side of the EPE material. As the EPE material is conveyed, the vertical distance between the hot pressing roller and the cold pressing eccentric roller gradually decreases.

[0014] In one embodiment, the temperature of the hot press roller is 170-210°C.

[0015] In one embodiment, after the hot press roller comes into contact with the EPE material, a semi-circular or elliptical recessed area is formed on the EPE material, and the recessed area is a dense thermoplastic deformation zone.

[0016] In one embodiment, the recessed areas are evenly arranged on the other side of the EPE material.

[0017] In one embodiment, the curvature of the hot-pressing wheel is greater than the curvature of the cold-pressing eccentric wheel.

[0018] In one embodiment, the hot press wheel employs eddy current heating.

[0019] According to a second aspect of this disclosure, a novel EPE material is provided, prepared according to the method described in any of the preceding claims, the novel EPE material comprising:

[0020] EPE raw materials;

[0021] Cold-pressed elastic deformation zone, wherein the cold-pressed elastic deformation zone is disposed on one side of the EPE raw material;

[0022] A thermoplastic deformation zone, wherein the thermoplastic deformation zone is disposed on the other side of the EPE raw material; and

[0023] A transition zone is provided between the cold-pressed elastic deformation zone and the thermoplastic deformation zone.

[0024] This disclosure provides a novel EPE material and its preparation method. The method involves cold pressing and hot pressing on both sides of the EPE raw material to form a recoverable cold-pressed elastic deformation zone and a dense thermoplastic deformation zone, with a transition zone between the two. The novel EPE material prepared by this method retains the inherent softness of EPE on its surface, while the plastically deformed areas exhibit good strength and toughness. Therefore, a novel EPE material with a soft surface and internal rigidity can be obtained, further broadening the application range of EPE materials.

[0025] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0026] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings. Several embodiments of this disclosure are illustrated in the drawings by way of example and not limitation, in which:

[0027] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0028] Figure 1 A schematic diagram of the structure of a novel EPE material according to an embodiment of this disclosure is shown;

[0029] Figure 2 A schematic diagram of the structure of a novel EPE composite material according to an embodiment of this disclosure is shown. Figure 1 ;

[0030] Figure 3 A schematic diagram of the structure of a novel EPE composite material according to an embodiment of this disclosure is shown. Figure 2 ;

[0031] Figure 4 A schematic diagram of the structure of a novel EPE composite material according to an embodiment of this disclosure is shown. Figure 3 ;

[0032] Figure 5 A schematic diagram of a novel EPE material preparation method according to an embodiment of this disclosure is shown;

[0033] Figure 6 A schematic diagram of a cold-pressed eccentric wheel according to an embodiment of the present disclosure is shown;

[0034] Figure 7 The diagram shows the G-value curve of a novel EPE material according to an embodiment of the present disclosure. Detailed Implementation

[0035] To make the objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0036] Example 1

[0037] like Figure 1The diagram shown is a structural schematic of a novel EPE material provided by the present invention. This novel EPE material includes:

[0038] EPE raw material 1;

[0039] Cold-pressed elastic deformation zone 2, wherein the cold-pressed elastic deformation zone 2 is disposed on one side of the EPE1 raw material;

[0040] Thermoplastic deformation zone 3, wherein the thermoplastic deformation zone 3 is disposed on the other side of the EPE raw material 1; and

[0041] Transition zone 4 is located between the cold-pressed elastic deformation zone 2 and the thermoplastic deformation zone 3.

[0042] This novel EPE material retains the inherent softness of EPE in its cold-pressed elastic deformation zone, while exhibiting good strength and toughness in its plastic deformation zone. Therefore, a new type of EPE material with a soft surface and internal rigidity can be obtained, further expanding the application range of EPE materials.

[0043] In one embodiment, two or more of the above-mentioned novel EPE materials can be composited to obtain a novel EPE composite material. For example... Figure 2 As shown, after two novel EPE materials are composited, another layer of EPE raw material is composited on the recessed thermoplastic deformation area, or the EPE raw material is composited after being cold-pressed.

[0044] In one embodiment, for example Figure 3 As shown, two novel EPE materials are arranged symmetrically, one above the other, and then the top and bottom surfaces are fixed to obtain a novel EPE composite material. Figure 4 As shown, two novel EPE materials are alternately arranged and fixed to obtain a novel EPE composite material, thus further broadening the application range of the novel EPE material. This invention does not limit the composite method or shape of the novel EPE composite material. Figure 2-4 This is for illustrative purposes only.

[0045] Example 2

[0046] like Figure 5 The diagram shows a method for preparing a novel EPE material, which includes the following steps:

[0047] S1. Cold pressing is performed on one side of the EPE raw material to cause elastic deformation on the cold-pressed side of the EPE raw material, forming a recoverable cold-pressed elastic deformation zone.

[0048] In one example, cold pressing is performed on one side of the EPE raw material, including:

[0049] EPE raw material is conveyed by a conveyor wheel, and a cold-pressing eccentric wheel is set above the conveyor wheel. The cold-pressing eccentric wheel is used to cold-press one side of the EPE raw material. The rotation direction of the cold-pressing eccentric wheel is opposite to the rotation direction of the conveyor wheel.

[0050] like Figure 6 The diagram shows a cold-pressed eccentric wheel; at least one elliptical protrusion is provided on the side wall of the cold-pressed eccentric wheel. When multiple elliptical protrusions are provided, the arrangement of the elliptical protrusions is not fixed. They can be arranged uniformly or non-uniformly. This invention does not impose any restrictions on this.

[0051] The rotation direction of the cold-pressing eccentric wheel is opposite to that of the conveyor wheel. If the conveyor wheel rotates clockwise, the cold-pressing eccentric wheel rotates counterclockwise. In one embodiment, the rotation speed of the conveyor wheel is 0.5 m / s, and the rotation speed of the cold-pressing eccentric wheel is also 0.5 m / s. To adjust the density of the plastic extrusion, the rotation speed of the cold-pressing eccentric wheel is slightly greater than that of the conveyor wheel, for example, set to 0.5-0.6 m / s. As the cold-pressing eccentric wheel rotates counterclockwise, the upward tangential velocity of the protrusion on the cold-pressing eccentric wheel is exactly in the same direction as the EPE raw material conveying direction, thus ensuring that the EPE raw material moves normally in the discharge direction.

[0052] Taking a rectangular EPE material as an example, the EPE material is placed on a conveyor wheel, which rotates clockwise. The cold-pressing eccentric wheel rotates counterclockwise above the conveyor wheel. When the protrusion on the cold-pressing eccentric wheel comes into contact with the upper surface of the EPE material, the upper surface of the EPE material undergoes elastic deformation under the pressure of the cold-pressing eccentric wheel.

[0053] S2. Hot pressing is performed on the other side of the EPE material to cause plastic deformation on the hot-pressed side of the EPE material, forming a dense thermoplastic deformation zone.

[0054] In one example, hot pressing is performed on the other side of the EPE material, including:

[0055] The hot pressing roller is located on one side of the transmission roller and is used to hot press the other side of the EPE material. As the EPE material is conveyed, the vertical distance between the hot pressing roller and the cold pressing eccentric roller gradually decreases.

[0056] The hot press roller is located at one end of the conveyor roller in the conveying direction, and the bottom surface of the EPE raw material is in contact with the hot press roller. In order to quickly heat the hot press roller and raise it to the working temperature, the hot press roller in this embodiment adopts eddy current heating, and the temperature is 170-210℃.

[0057] When the protrusion of the cold-pressing eccentric wheel begins to contact the EPE material, the heating switch of the hot-pressing wheel is turned on, and the temperature of the hot-pressing wheel rises rapidly under eddy current heating. At this time, as the EPE material is conveyed, the vertical distance between the cold-pressing eccentric wheel and the hot-pressing wheel gradually decreases, and the upper and lower surfaces of the EPE material will be subjected to a force F of the same magnitude.

[0058] In one example, the curvature of the hot-pressing wheel is greater than that of the cold-pressing eccentric wheel. Since the curvature of the hot-pressing wheel is greater than that of the cold-pressing wheel, under the same force F, the pressure on the surface of the EPE material on the cold-pressing eccentric wheel is less than that on the surface of the hot-pressing wheel. On the surface of the hot-pressing wheel, due to the heating effect on the bottom surface of the EPE material, the EPE material is very easy to be plastically deformed.

[0059] S3. The area between the cold-pressed elastic deformation zone and the thermoplastic deformation zone is a transition zone.

[0060] On the hot pressing wheel surface and the cold pressing eccentric wheel surface, the EPE raw material forms hot pressing and cold pressing effects respectively; under hot pressing, the EPE raw material undergoes plastic deformation; under cold pressing, the EPE raw material undergoes elastic deformation.

[0061] On the hot-pressing roller surface, EPE is rapidly extruded into dense, high-density EPE, achieving the purpose of modifying EPE. On the cold-pressing eccentric roller surface, the pressure is insufficient to cause elastic deformation of EPE, so its density remains unchanged. The transition zone lies between the cold-pressing elastic deformation zone and the thermoplastic deformation zone; the density of EPE in the transition zone is between that of the cold-pressing elastic deformation zone and the thermoplastic deformation zone.

[0062] Mechanical property simulation analysis was performed on the novel EPE material prepared in the embodiments of the present invention. Figure 7 The image shows the G-value curves for the new EPE material and the original EPE material. The curves show that the G-value of the new EPE material is significantly lower than that of the commonly used EPE material. This is because vibration transmission is determined by the density of the material; the higher the density, the greater the kinetic energy transmitted, the greater the vibration, and the greater the gravitational effect. According to... Figure 7 This indicates that the new EPE material has a low density, and its corresponding G value is small.

[0063] The novel EPE material produced using the preparation process of this invention retains the softness of EPE itself on the surface, while the semi-circular core region undergoes plastic deformation and exhibits good strength and toughness. This results in a novel EPE material that is soft on the surface and rigid and tough on the inside.

[0064] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0065] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0066] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A method for preparing a novel EPE material, characterized in that, The method includes: EPE raw material is conveyed by a conveyor wheel, and a cold-pressing eccentric wheel is provided above the conveyor wheel. At least one elliptical protrusion is provided on the side wall of the cold-pressing eccentric wheel. A hot-pressing wheel is provided on one side of the conveyor wheel, and the curvature of the hot-pressing wheel is greater than that of the cold-pressing eccentric wheel. The EPE raw material is cold-pressed on one side by the cold-pressing eccentric wheel. The rotation direction of the cold-pressing eccentric wheel is opposite to the rotation direction of the conveying wheel, so that the cold-pressed side of the EPE raw material undergoes elastic deformation, forming a recoverable cold-pressing elastic deformation zone. Hot pressing is performed on the other side of the EPE raw material by the hot pressing roller heated by eddy current, so that the hot pressing side of the EPE raw material undergoes plastic deformation to form a dense thermoplastic deformation zone; as the EPE raw material is conveyed, the vertical distance between the hot pressing roller and the cold pressing eccentric roller gradually decreases; the temperature of the hot pressing roller is 170-210℃; The transition zone is between the cold-pressed elastic deformation zone and the thermoplastic deformation zone; The EPE material is a non-crosslinked closed-cell foam formed by physical foaming of low-density polyethylene.

2. The method according to claim 1, characterized in that, After the hot press roller comes into contact with the EPE material, a semi-circular or elliptical recessed area is formed on the EPE material. The recessed area is a dense thermoplastic deformation zone.

3. The method according to claim 2, characterized in that, The recessed areas are evenly arranged on the other side of the EPE material.

4. A novel EPE material, characterized in that, The novel EPE material is prepared according to any one of claims 1-3, and comprises: EPE raw materials; Cold-pressed elastic deformation zone, wherein the cold-pressed elastic deformation zone is disposed on one side of the EPE raw material; A thermoplastic deformation zone, wherein the thermoplastic deformation zone is disposed on the other side of the EPE raw material; and A transition zone is provided between the cold-pressed elastic deformation zone and the thermoplastic deformation zone.

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