Plastic fireproof material for extrusion

Abstract

The invention discloses a plastic fireproof material for extrusion. The invention belongs to the technical field of plastic particles capable of reaching the fireproof grade A (non-combustible grade), magnesium hydroxide, aluminum hydroxide and other additives are reasonably added into the PE plastic particles, the fireproof grade A non-combustible grade standard is successfully reached, compared with existing plastic particles only capable of reaching the fireproof grade B, the fireproof safety is remarkably improved, and the service life of the plastic particles is prolonged. The cable can be widely applied to places with strict fireproof requirements, and the fire risk is effectively reduced; the raw materials are subjected to constant-temperature drying treatment in the pretreatment process, so that the raw materials flow and fill a mold more easily in the injection molding process, the production efficiency is improved, the quality and performance of a final product can be ensured, the defects of yellowing, silver wires, bubbles, shrinkage cavities and the like of the product are avoided, and the yield of the product is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic particles capable of achieving fireproofing grade A (non-combustible grade), and specifically refers to a plastic fireproof material for extrusion. Background Art

[0002] In modern industry and daily life, plastic products are widely used in many fields such as construction, packaging, and electronic appliances due to their advantages such as light weight, corrosion resistance, and easy processing. As the basic raw material for the production of plastic products, the performance of plastic particles directly affects the quality and application scope of the final product. Among the many performance requirements, fire resistance has received more and more attention, especially in scenarios with extremely high fire safety requirements, the fire resistance of plastic materials has become a key consideration.

[0003] In the field of construction, with the acceleration of urbanization, high-rise buildings, large commercial complexes, public transportation hubs and other buildings are constantly emerging. These buildings are densely populated and complex in function. Once a fire occurs, the fire spreads rapidly, which can easily cause heavy casualties and property losses. For example, in some high-rise office buildings, a large number of plastic products are used in interior decoration. If these plastic products have poor fire resistance, when a fire occurs, the burning of plastic will not only produce high-temperature flames, but also release a large amount of toxic and harmful gases, which seriously hinders the evacuation of personnel and fire rescue work. In the 2017 Grenfell Tower fire in London, the insulation material of the building's exterior wall was made of flammable plastic material. The fire spread rapidly, causing heavy casualties and huge property losses. This incident also triggered global attention to the fire safety of building materials.

[0004] In the field of electronics and electrical appliances, with the popularization of electronic products and the acceleration of the replacement speed, the risk of fire caused by electrical faults during the use of electronic equipment is also increasing. For example, the shells of electronic products such as mobile phones and computers, and the insulation materials of internal circuits are mostly plastic products. If these plastic materials do not have good fire resistance, once a short circuit or other fault occurs, the plastic products are very easy to burn, which in turn causes a fire and threatens the safety of users' lives and property.

[0005] At present, most of the plastic particles used in the aluminum-plastic panel industry on the market can only meet the fireproof Class B (flame-retardant) standard. This situation severely limits its application in some places with strict fire protection requirements. The fire protection code clearly stipulates that in specific building areas and application scenarios, materials with fireproof performance reaching Class A (non-combustible grade) must be used. For example, in key parts of a building's fire passages, fire walls, elevator shafts, and in crowded public buildings such as hospitals, schools, and libraries, the plastic materials used must meet the fireproof Class A standard. However, existing plastic particles cannot meet this requirement, resulting in the need to find other alternative materials or adopt additional fire protection measures in actual applications, which not only increases costs, but may also affect the overall performance and aesthetics of the product.

[0006] In order to improve the fire resistance of plastic particles, researchers and related companies have conducted a lot of research and attempts. Some studies have tried to add flame retardants to plastics to improve fire resistance, but the addition of traditional flame retardants often has a negative impact on other properties of plastics, such as mechanical properties and processing properties, resulting in a decrease in the overall performance of the product. For example, although some halogen-containing flame retardants have good flame retardant effects, they will release a large amount of toxic and harmful gases during the combustion process, causing serious harm to the environment and human health; and when some inorganic flame retardants are added in large amounts, the toughness of the plastic will be reduced, and the product will be prone to cracking and other problems.

[0007] In addition, the existing plastic particle preparation process also has certain limitations in improving fire resistance. The traditional preparation process makes it difficult to achieve uniform dispersion of flame retardant components in the plastic matrix, resulting in unstable fire resistance of the product. The fire resistance of different batches of products varies greatly, and the market demand for high-quality and high-performance plastic particles cannot be met.

[0008] In summary, the development of a plastic particle that can meet the fire protection grade A standard and has good comprehensive performance and a stable preparation process has important practical significance and market demand. Summary of the invention

[0009] The purpose of the present invention is to provide a new formula of plastic particles, and the plastic particles prepared by the formula can meet the fireproof A-level non-combustible grade standard, thereby breaking through the limitations of existing plastic particles in terms of fireproof performance and meeting the needs of more application scenarios with strict fireproof requirements. The present invention successfully meets the fireproof A-level non-combustible grade standard by reasonably adding magnesium hydroxide, aluminum hydroxide components and other additives to PE plastic particles. Compared with the existing plastic particles that can only reach the fireproof B level, the fire safety is significantly improved, and it can be widely used in places with strict fireproof requirements to effectively reduce the risk of fire; the raw materials are subjected to a constant temperature drying treatment during the pretreatment process, and are easier to flow and fill the mold during the injection molding process, which not only improves the production efficiency, but also can ensure the quality and performance of the final product, avoid the appearance of yellowing, silver threads, bubbles, shrinkage holes and other defects in the product, and improve the product yield rate.

[0010] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows: a plastic fireproof material for extrusion, which includes the following components by weight: 3-10% polyethylene plastic particles, 30-50% magnesium hydroxide, 40-50% aluminum hydroxide, and 2-8% mixed additives.

[0011] Preferably, the plastic fireproof material comprises the following components in parts by weight: 8-10% polyethylene plastic particles, 38-42% magnesium hydroxide, 44-46% aluminum hydroxide, and 4-6% mixed additives.

[0012] Preferably, the plastic fireproof material comprises the following components in parts by weight: 10% polyethylene plastic particles, 40% magnesium hydroxide, 45% aluminum hydroxide, and 5% mixed additives.

[0013] Preferably, the mixed additive consists of an antioxidant, a lubricant, a coupling agent and a dispersant.

[0014] Preferably, the antioxidant is one or more of a hindered phenol antioxidant and a phosphite antioxidant.

[0015] Preferably, the lubricant is one or more of stearic acid and zinc stearate.

[0016] Preferably, the coupling agent is one or more of a silane coupling agent and a titanate coupling agent.

[0017] Preferably, the dispersant is one or more of fatty acids and fatty amides.

[0018] The present invention also provides a preparation process of a plastic fireproof material for extrusion, the preparation process comprising the following steps:

[0019] (1) Raw material preparation and pretreatment: the raw materials are placed in a constant temperature drying oven and dried for 20 hours. After drying, these raw materials are easier to flow and fill the mold during the injection molding process, thereby improving production efficiency. After the moisture is removed, the quality and performance of the final product can be ensured, and defects such as yellowing, silver streaks, bubbles, and shrinkage holes can be avoided;

[0020] (2) Feeding and conveying: take out the raw materials in the constant temperature drying oven, weigh the corresponding mass portions according to the proportion together with the other raw materials that do not need to be dried, and convey them to the feeding port of the twin-screw extruder through a screw feeder at a feeding speed of 120 r / min;

[0021] (3) Heating and melting: the raw material particles are heated and melted in the twin-screw extruder to form a uniform plastic melt. During this process, the main engine speed is 260r / min;

[0022] (4) Plasticizing and mixing. The threads on the screw shear, extrude, and convey the material. Under the combined action of heating and shearing force, the material gradually melts and plasticizes, and is fully mixed. The meshing structure of the twin screws helps to distribute and disperse the material.

[0023] (5) Cooling and solidification: the material after plasticization and mixing is pushed to the die head, extruded through a specific hole pattern on the die to form a strip-shaped material, and then rapidly cooled and solidified by underwater cooling;

[0024] (6) Extrusion granulation, using a pelletizing device to cut the strip material into pellets of desired length;

[0025] (7) separation and screening, placing the cooled particles into a vibrating screening machine for screening and separation to obtain finished particles that meet the specifications;

[0026] (8) Packaging and storage: the qualified finished particles are dried in a constant temperature drying oven at 100 degrees Celsius for 6 hours, and then the treated plastic particles are packaged and stored in a dry and cool environment to prevent moisture and deterioration;

[0027] (9) Randomly select product samples, dry them in a constant temperature drying oven at 100 degrees Celsius for 5 hours, and use an injection molding machine to make standard specimens;

[0028] (10) After the standard specimen is prepared, it is allowed to stand for 24 hours before the material index is measured.

[0029] The beneficial effects achieved by the present invention using the above structure are as follows: (1) The present invention successfully achieves the fireproof A-level non-combustible standard by reasonably adding magnesium hydroxide, aluminum hydroxide and other additives to PE plastic particles. Compared with the existing plastic particles that can only achieve fireproof B-level, the fire safety is significantly improved, and the material can be widely used in places with strict fire protection requirements to effectively reduce the risk of fire; (2) The raw materials are subjected to constant temperature drying treatment during the pretreatment process, which makes it easier to flow and fill the mold during the injection molding process, which not only improves the production efficiency, but also ensures the quality and performance of the final product, avoids defects such as yellowing, silver threads, bubbles, shrinkage holes, etc., and improves the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Peak heat release rate.

[0031] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 this field without making creative work are within the scope of protection of the present invention.

[0033] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0034] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials and test strains used in the following examples are purchased from commercial channels unless otherwise specified.

[0035] Example 1

[0036] Plastic fireproof material for extrusion

[0037] The plastic fireproof material comprises the following components in parts by weight: 10% polyethylene plastic particles, 40% magnesium hydroxide, 45% aluminum hydroxide and 5% mixed additives.

[0038] Wherein, the mixed additive consists of an antioxidant, a lubricant, a coupling agent and a dispersant.

[0039] Wherein, the antioxidant is a hindered phenol antioxidant; the lubricant is stearic acid; and the coupling agent is a silane coupling agent.

[0040] Wherein, the dispersant is fatty acid.

[0041] The present invention also provides a preparation process of a plastic fireproof material for extrusion, the preparation process comprising the following steps:

[0042] (1) Raw material preparation and pretreatment: the raw materials are placed in a constant temperature drying oven and dried for 20 hours. After drying, these raw materials are easier to flow and fill the mold during the injection molding process, thereby improving production efficiency. After the moisture is removed, the quality and performance of the final product can be ensured, and defects such as yellowing, silver streaks, bubbles, and shrinkage holes can be avoided;

[0043] (2) Feeding and conveying: take out the raw materials in the constant temperature drying oven, weigh the corresponding mass portions according to the proportion together with the other raw materials that do not need to be dried, and convey them to the feeding port of the twin-screw extruder through a screw feeder at a feeding speed of 120 r / min;

[0044] (3) Heating and melting: the raw material particles are heated and melted in the twin-screw extruder to form a uniform plastic melt. During this process, the main engine speed is 260r / min;

[0045] (4) Plasticizing and mixing. The threads on the screw shear, extrude, and convey the material. Under the combined action of heating and shearing force, the material gradually melts and plasticizes, and is fully mixed. The meshing structure of the twin screws helps to distribute and disperse the material.

[0046] (5) Cooling and solidification: the material after plasticization and mixing is pushed to the die head, extruded through a specific hole pattern on the die to form a strip-shaped material, and then rapidly cooled and solidified by underwater cooling;

[0047] (6) Extrusion granulation, using a pelletizing device to cut the strip material into pellets of desired length;

[0048] (7) separation and screening, placing the cooled particles into a vibrating screening machine for screening and separation to obtain finished particles that meet the specifications;

[0049] (8) Packaging and storage: the qualified finished particles are dried in a constant temperature drying oven at 100 degrees Celsius for 6 hours, and then the treated plastic particles are packaged and stored in a dry and cool environment to prevent moisture and deterioration;

[0050] (9) Randomly select product samples, dry them in a constant temperature drying oven at 100 degrees Celsius for 5 hours, and use an injection molding machine to make standard specimens;

[0051] (10) After the standard specimen is prepared, it is allowed to stand for 24 hours before the material index is measured.

[0052] Example 2

[0053] Plastic fireproof material for extrusion

[0054] The plastic fireproof material comprises the following components in parts by weight: 10% polyethylene plastic particles, 40% magnesium hydroxide, 45% aluminum hydroxide and 5% mixed additives.

[0055] Wherein, the mixed additive consists of an antioxidant, a lubricant, a coupling agent and a dispersant.

[0056] Wherein, the antioxidant is a phosphite antioxidant; the lubricant is zinc stearate; the coupling agent is a titanate coupling agent; and the dispersant is aliphatic amide.

[0057] The present invention also provides a preparation process of a plastic fireproof material for extrusion, and the preparation process is implemented with reference to Example 1.

[0058] Example 3

[0059] Plastic fireproof material for extrusion

[0060] The plastic fireproof material comprises the following components in parts by weight: 10% polyethylene plastic particles, 40% magnesium hydroxide, 45% aluminum hydroxide and 5% mixed additives.

[0061] Wherein, the mixed additive consists of an antioxidant, a lubricant, a coupling agent and a dispersant.

[0062] Wherein, the antioxidant is a hindered phenol antioxidant; the lubricant is zinc stearate; the coupling agent is a silane coupling agent; and the dispersant is aliphatic amides.

[0063] The present invention also provides a preparation process of a plastic fireproof material for extrusion, and the preparation process is implemented with reference to Example 1.

[0064] Experimental Example 1

[0065] The plastic fireproof materials prepared in Example 1, Example 2 and Example 3 were used as test samples, with 3 replicates in each group, and were divided into Example 1-Example 3 groups. The control group selected common fireproof materials on the market, and the samples were tested using a cone calorimeter to record the peak heat release rate. According to the relevant fire protection grade judgment standard, if the peak heat release rate is lower than a certain threshold, it is judged to meet the fire protection grade A standard.

[0066] Result analysis: Figure 1As shown, the peak values ​​of heat release rates of Examples 1-3 are all at a relatively low level, lower than the specified 300KW / m 2 , while the peak heat release rate of the control group was much higher than that of the groups in Examples 1-3.

[0067] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0068] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A plastic fireproof material for extrusion, characterized in that: The plastic fireproof material comprises the following components in parts by weight: 3-10% polyethylene plastic particles, 30-50% magnesium hydroxide, 40-50% aluminum hydroxide and 2-8% mixed additives.

2. A plastic fireproof material for extrusion according to claim 1, characterized in that: The plastic fireproof material comprises the following components in parts by weight: 8-10% of polyethylene plastic particles, 38-42% of magnesium hydroxide, 44-46% of aluminum hydroxide and 4-6% of mixed additives.

3. A plastic fireproof material for extrusion according to claim 2, characterized in that: The plastic fireproof material comprises the following components in parts by weight: 10% polyethylene plastic particles, 40% magnesium hydroxide, 45% aluminum hydroxide and 5% mixed additives.

4. A plastic fireproof material for extrusion according to claim 3, characterized in that: The mixed additive consists of an antioxidant, a lubricant, a coupling agent and a dispersant.

5. A plastic fireproof material for extrusion according to claim 4, characterized in that: The antioxidant is one or more of a hindered phenol antioxidant and a phosphite antioxidant.

6. A plastic fireproof material for extrusion according to claim 5, characterized in that: The lubricant is one or more of stearic acid and zinc stearate.

7. A plastic fireproof material for extrusion according to claim 6, characterized in that: The coupling agent is one or more of a silane coupling agent and a titanate coupling agent.

8. A plastic fireproof material for extrusion according to claim 7, characterized in that: The dispersant is one or more of fatty acids and aliphatic amides.

9. A process for preparing a plastic fireproof material for extrusion according to claim 8, characterized in that: The preparation process comprises the following steps: (1) Raw material preparation and pretreatment: the raw materials are placed in a constant temperature drying oven and dried for 20 hours. After drying, these raw materials are easier to flow and fill the mold during the injection molding process, thereby improving production efficiency. After the moisture is removed, the quality and performance of the final product can be ensured, and defects such as yellowing, silver streaks, bubbles, and shrinkage holes can be avoided; (2) Feeding and conveying: take out the raw materials in the constant temperature drying oven, weigh the corresponding mass portions according to the proportion together with the other raw materials that do not need to be dried, and convey them to the feeding port of the twin-screw extruder through a screw feeder at a feeding speed of 120 r / min; (3) Heating and melting: the raw material particles are heated and melted in the twin-screw extruder to form a uniform plastic melt. During this process, the main engine speed is 260r / min; (4) Plasticizing and mixing. The threads on the screw shear, extrude, and convey the material. Under the combined action of heating and shearing force, the material gradually melts and plasticizes, and is fully mixed. The meshing structure of the twin screws helps to distribute and disperse the material. (5) Cooling and solidification: the material after plasticization and mixing is pushed to the die head, extruded through a specific hole pattern on the die to form a strip-shaped material, and then rapidly cooled and solidified by underwater cooling; (6) Extrusion granulation, using a pelletizing device to cut the strip material into pellets of desired length; (7) separation and screening, placing the cooled particles into a vibrating screening machine for screening and separation to obtain finished particles that meet the specifications; (8) Packaging and storage: the qualified finished particles are dried in a constant temperature drying oven at 100 degrees Celsius for 6 hours, and then the treated plastic particles are packaged and stored in a dry and cool environment to prevent moisture and deterioration; (9) Randomly select product samples, dry them in a constant temperature drying oven at 100 degrees Celsius for 5 hours, and use an injection molding machine to make standard specimens; (10) After the standard specimen is prepared, it is allowed to stand for 24 hours before the material index is measured.

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