Forming process of environment-friendly foaming material

Abstract

The invention discloses a molding process of an environment-friendly foaming material. The molding process comprises the following steps: extruding raw material particles into a particle extrusion plate through an extruder; the extrusion plate is placed in a drying oven to be tempered and heated; after a vulcanizing machine is preheated to the set temperature, the extrusion plate in the drying oven is transferred into a mold of the vulcanizing machine; filling gas into the vulcanizing machine, and melting the gas into the extrusion plate through high temperature and high pressure; after the vulcanization time is up, quick pressure relief is carried out, bubble nucleuses are formed in an extrusion plate through instant exhaust, and a foaming plate is formed through quick foaming at the instant of mold opening; opening the mold, setting and cooling each layer of foaming plate in a setting machine, storing for more than 7 days for subsequent processing, melting the gas into the material through high temperature and high pressure by using the carbon dioxide gas with the highest boundary value, and instantly exhausting to form a bubble core. The foam board is foamed quickly at the moment of mold opening, bubbles are formed, the foam board adopts microcellular foaming, the percentage of close area reaches 95%, and the foam board has the advantages of being made of light high-strength materials, having buffering and blocking capacity, being low in water absorption rate and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of foaming materials, and in particular relates to a molding process of an environmentally friendly foaming material. Background Art

[0002] EVA foaming technology has been used since the 1920s and is still in use today. EVA foaming materials have greatly improved people's daily lives and can be used in crawling mats, insoles, shoe midsoles, yoga mats, packaging supplies, etc. These products are fully accepted by the general public and are of good quality and low price.

[0003] However, since EVA foaming is done with AC foaming agent, and AC foaming agent will produce a large amount of irritating, unpleasant-smelling toxic gases when exposed to high temperatures, these gases are inhaled into the human body and have a very high carcinogenic rate.

[0004] At the same time, since EVA foaming is achieved through cross-linking, the structure of the raw materials has changed, which makes the raw materials unable to be recycled and reused, and it is also difficult to degrade, and is not environmentally friendly. Summary of the invention

[0005] In order to overcome the above-mentioned shortcomings, the inventor of the present invention has proposed a molding process of an environmentally friendly foam material through long-term exploration and attempts, multiple experiments and efforts, continuous reform and innovation, and proposed a molding process of an environmentally friendly foam material, which uses the highest threshold carbon dioxide gas, through high temperature and high pressure, to melt the gas into the material, and forms bubble nuclei through instant exhaust. At the moment of mold opening, foaming is rapid to form bubbles. The foaming board is microporous foaming, and the closed cell rate reaches 95%. It has the advantages of light weight and high strength material, buffer barrier capacity, low water absorption rate, etc.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a molding process of an environmentally friendly foaming material. The steps include: S1, raw material particles are extruded into particle extrusion plates through an extruder; S2, the extrusion plates are placed in an oven for tempering and heating, and the tempering and heating placement time is 1h-4h; S3, after the vulcanizer is preheated to a set temperature, the extrusion plates in the oven are transferred to the mold of the vulcanizer, the temperature reduction range is controlled within 5°C-8°C during the transfer process, and the vulcanization time is 40min-120min; S4, gas is filled into the vulcanizer, the gas pressure is maintained at 200bar-220bar, and the gas is melted into the extrusion plates through high temperature and high pressure; S5, after the vulcanization time is reached, the pressure is quickly released to achieve instantaneous exhaust to form bubble nuclei in the extrusion plates, and bubbles are rapidly foamed to form bubbles at the moment of mold opening, and the extrusion plates are foamed into foam plates; S6, the mold of the vulcanizer is opened, and each layer of foam plates is placed in a shaping machine for shaping and cooling; S7, the cooled foam plates are stored for more than 7 days for subsequent processing.

[0007] According to the molding process of an environmentally friendly foaming material described in the present invention, its further preferred technical scheme is: it also includes a subsequent processing step S8, specifically: S8.1, the release paper placed on the unwinding device is pulled out by the roller, enters the tension system after automatic deviation correction, and enters the coating head after adjusting the unwinding tension; S8.2, the release paper is coated with glue in the glue tank and scraped flat with a scraper, and then enters the oven to be dried by hot air; S8.3, the release paper comes out of the oven and is laminated with the substrate through the laminating roller, and then passes through two sets of clamping wheels to make the substrate and the glue layer firmly laminated, and finally rolled up.

[0008] According to the molding process of an environmentally friendly foam material described in the present invention, a further preferred technical solution is: + In the step S8.3, the foam material that meets the width and thickness requirements after cutting is used as the base material.

[0009] According to the molding process of an environmentally friendly foaming material described in the present invention, a further preferred technical solution is: in step S1, the raw material is new raw material particles, or a raw material formed by mixing recycled foaming material particles with new raw material particles.

[0010] According to the molding process of the environmentally friendly foaming material described in the present invention, a further preferred technical solution is: in step S1, the temperature process range of the raw material extruded by the extruder is 140°C-220°C.

[0011] According to the molding process of an environmentally friendly foam material described in the present invention, a further preferred technical solution is: in step S2, the tempering temperature range is 80-100°C.

[0012] According to the molding process of an environmentally friendly foam material described in the present invention, a further preferred technical solution is: in the step S4, the gas filled is a gas that does not react with the foam material.

[0013] According to the molding process of an environmentally friendly foaming material described in the present invention, a further preferred technical solution is that the gas is carbon dioxide gas.

[0014] According to the molding process of the environmentally friendly foaming material described in the present invention, a further preferred technical solution is: maximum threshold carbon dioxide gas.

[0015] According to the molding process of an environmentally friendly foam material described in the present invention, a further preferred technical solution is: in the step S5, the pressure relief time needs to be maintained within 3-5S.

[0016] Compared with the prior art, the technical solution of the present invention has the following advantages / benefits: 1. The present invention utilizes the highest threshold carbon dioxide gas, through high temperature and high pressure, to melt the gas into the material, and forms bubble nuclei through instant exhaust. At the moment of mold opening, it foams rapidly to form bubbles. The foaming board is microporous foaming with a closed cell rate of 95%. It has the advantages of light weight and high strength material, buffer barrier capacity, low water absorption, etc.

[0017] 2. When the gas with heat source passes through the foam board, since the closed-pore rate of the material is more than 95%, the gas heat transfer is slow and the thermal conductivity coefficient can be low, so it can be used as a thermal insulation material.

[0018] 3. The foamed board of the present invention can be guaranteed to be non-toxic and harmless. During the foaming process, pure physical foaming is used without adding foaming agent. There is no decomposition of the foaming agent under high temperature conditions to produce gases that are harmful to the human body. This meets the national requirements for "dual carbon" energy conservation and environmental protection.

[0019] 4. The material is a thermoplastic material and has not been cross-linked. It can be recycled and reused by crushing the extruder and re-granulating. Mixing it with new raw material particles can avoid the breakage of the molecular chain under repeated heating, which will lead to a significant decrease in the mechanical properties of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 The present invention is a flow chart of a molding process of an environmentally friendly foaming material. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. Therefore, the detailed description of the embodiments of the present invention provided below is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention.

[0023] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and thus, once an item is defined in one drawing, it may not be further defined or explained in the subsequent drawings.

[0024] Embodiment 1: like Figure 1 As shown, a molding process of an environmentally friendly foaming material. The steps include: S1, raw material particles (such as LDPE material particles) are extruded by an extruder to become particle extrusion plates. The temperature process range of the raw material extruded by the extruder is 140℃-220℃. The raw material is a brand new raw material particle, or a raw material formed by mixing recycled foaming material particles with new raw material particles. Regarding the mixing ratio, it is generally required that the proportion of recycled materials is between 20%-50%. When recycled and reused, the physical properties of the material decrease. When the thermoplastic material is repeatedly heated, the molecular chain will break, resulting in a significant decrease in the mechanical properties of the material. Therefore, it is necessary to reduce the proportion of waste materials and mix them with new materials to reduce the degree of decrease in their physical properties. The better range is 20%-25%. At this time, the performance difference of the materials is basically not affected; S2, put the extruded plate in an oven for tempering and heating. The tempering and heating time is 1h-4h, and the tempering and heating temperature range is 80-100℃. Of course, the tempering and heating time and temperature range will vary depending on the raw materials. Just make reasonable adjustments. At the same time, due to the mixed recycled foaming material particles (obtained by recycled granulation), the time and temperature will also be affected to a certain extent. Adjust according to the actual test parameters. If necessary, the tempering and heating time can be extended; S3, after the vulcanizer is preheated to the set temperature, the extruded plate in the oven is transferred to the mold of the vulcanizer. The temperature drop during the transfer process is controlled within 5℃-8℃. The vulcanization time is 40min-120min. The temperature of the extruded plate in the oven cannot be reduced too much to avoid affecting the vulcanization effect. Inconsistent internal and external temperatures lead to inconsistent performance. The vulcanization time is related to the vulcanization temperature. The vulcanization technology is relatively mature, so no temperature limit is imposed here. S4, fill the vulcanizer with gas, the gas pressure is maintained at 200bar-220bar, and the gas is melted into the extruded plate through high temperature and high pressure. The gas filled is a gas that does not react with the foaming material, such as carbon dioxide, nitrogen, etc., using the highest threshold carbon dioxide gas, through high temperature and high pressure, the gas is melted into the material, and through instant exhaust, bubble nuclei are formed to achieve a technical effect of high closed cell rate. The gas to be filled needs to consider the time of welding in the material of the extruded plate, so it is more reasonable to use carbon dioxide. At the same time, for the effect, the use of nitrogen and the like requires increasing the nitrogen pressure to speed up the dissolution time; S5, after the vulcanization time is reached, the pressure is quickly released to achieve instant exhaust to form bubble nuclei in the extruded plate, and bubbles are rapidly foamed to form bubbles at the moment of mold opening. The extruded plate is foamed into a foamed plate. Under normal circumstances, the pressure release time needs to be maintained within 3-5S to achieve rapid foaming and ensure the performance of the foamed plate; S6, open the mold of the vulcanizer, and place each layer of foamed board in a setting machine for setting and cooling. The setting machine can be used as needed, and the shape can be limited to a certain extent if necessary; S7, the cooled foamed board is stored for more than 7 days for subsequent processing.

[0025] The subsequent processing step S8 is also included, specifically: S8.1, the release paper placed on the unwinding device is pulled out by the roller, enters the tension system after automatic deviation correction, and enters the coating head after adjusting the unwinding tension; S8.2, the release paper is coated with glue in the glue tank and scraped flat by a scraper, and then enters the oven to be dried by hot air; S8.3, the release paper comes out of the oven and is laminated with the substrate by the laminating roller, and then the substrate and the adhesive layer are firmly laminated by two sets of pressure wheels, and finally rolled up. In this step, the foam material that meets the width and thickness requirements after cutting is generally used as the substrate for processing.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A molding process of an environmentally friendly foam material, characterized in that: The steps include: S1, raw material particles are extruded into particle extrusion plates through an extruder; S2, the extrusion plates are placed in an oven for tempering and heating, and the tempering and heating placement time is 1h-4h; S3, after the vulcanizer is preheated to a set temperature, the extrusion plates in the oven are transferred to the mold of the vulcanizer, the temperature reduction range is controlled within 5°C-8°C during the transfer process, and the vulcanization time is 40min-120min; S4, gas is filled into the vulcanizer, the gas pressure is maintained at 200bar-220bar, and the gas is melted into the extrusion plates through high temperature and high pressure; S5, after the vulcanization time is reached, the pressure is quickly released to achieve instantaneous exhaust to form bubble nuclei in the extrusion plates, and bubbles are rapidly foamed to form bubbles at the moment of mold opening, and the extrusion plates are foamed into foam plates; S6, the mold of the vulcanizer is opened, and each layer of foam plates is placed in a shaping machine for shaping and cooling; S7, the cooled foam plates are stored for more than 7 days for subsequent processing.

2. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: The subsequent processing step S8 is also included, specifically: S8.1, the release paper placed on the unwinding device is pulled out by the roller, enters the tension system after automatic deviation correction, and enters the coating head after adjusting the unwinding tension; S8.2, the release paper is coated with glue in the glue tank and scraped with a scraper, and then enters the oven to be dried by hot air; S8.3, the release paper comes out of the oven and passes through the laminating roller to laminate with the substrate, and then passes through two sets of pressing wheels to make the substrate and the adhesive layer firmly laminated, and finally it is rolled up.

3. The molding process of an environmentally friendly foam material according to claim 2, characterized in that: In step S8.3, the foamed material that meets the width and thickness requirements after cutting is used as the base material.

4. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: In step S1, the raw material is new raw material particles, or a raw material formed by mixing recycled foaming material particles with new raw material particles.

5. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: In step S1, the temperature process range of the raw material extruded by an extruder is 140°C-220°C.

6. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: In step S2, the tempering temperature range is 80-100°C.

7. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: In the step S4, the gas injected is a gas that does not react with the foaming material.

8. The molding process of an environmentally friendly foam material according to claim 7, characterized in that: The gas is carbon dioxide gas.

9. A molding process for an environmentally friendly foam material according to claim 7 or 8, characterized in that: Maximum threshold value of carbon dioxide gas.

10. The molding process of an environmentally friendly foam material according to claim 1, characterized in that: In step S5, the pressure relief time needs to be maintained within 3-5S.

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