A high-toughness flame-retardant heat-resistant plastic and preparation method thereof

Abstract

The invention discloses a high-toughness flame-retardant and heat-resistant plastic and a preparation method thereof, and relates to the technical field of plastic preparation. The raw materials thereof include the following components by mass: 20-32 parts of polycarbonate, 15-24 parts of polypropylene, 10-45 parts of high-density polyethylene, and 16-25 parts of ABS resin. The invention adds decabromodiphenylethane and ultrafine calcium silicate into a stirring tank in a mass ratio of (1-3): (2-5), stirs for 13 minutes under a stirring speed of 94rpm, and fully mixes the two to prepare a synergistic flame retardant for standby use. The synergistic flame retardant configured in proportion can effectively improve the flame retardant grade, will not cause harm to the environment when used, and the plastic made of the synergistic flame retardant can be recycled, which can effectively improve the utilization efficiency of plastic products. By uniformly blending the synergistic flame retardant with the mixture in proportion, the flame retardant performance of the mixture is effectively improved, and a modified plastic strip with high flame retardancy, high toughness and heat resistance is prepared, thereby improving the preparation efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of plastic preparation, in particular to a high-toughness flame-retardant and heat-resistant plastic and a preparation method thereof. Background Art

[0002] Plastics are important organic synthetic polymer materials with a wide range of applications. The flame retardants used in the preparation of existing plastics have average flame retardant effects and usually contain harmful substances, which causes the prepared plastics to burden the environment. In addition, plastic products cannot be recycled, resulting in a huge waste of resources.

[0003] The defects of existing plastic preparation are:

[0004] 1. Patent document CN114106421B discloses a heat-resistant degradable plastic and a preparation method thereof, which mainly considers making the prepared heat-resistant degradable plastic have good heat resistance and impact resistance, but does not consider how to effectively improve the flame retardant grade and use safety of the flame retardant;

[0005] 2. Patent document CN101845220B discloses flame retardant reinforced plastic and its preparation method, which mainly considers solving the problem of poor surface quality of existing flame retardant reinforced plastic, but does not consider how to reduce the environmental burden when preparing plastic products;

[0006] 3. Patent document CN113105734B discloses a method for preparing weather-resistant, high-toughness, wear-resistant and flame-retardant alloy plastic materials. It mainly considers improving the components of plastic materials and improving the weather resistance, toughness, wear resistance and flame retardancy of the materials, but does not consider the uneven fusion of reagents in the process of preparing plastics;

[0007] 4. Patent document CN107759913B discloses high-toughness antibacterial plastics and their preparation process. It mainly considers how to prepare plastics with good antibacterial ability and excellent mechanical properties and processing properties, but does not consider how to improve the flame retardancy and heat resistance of plastic products. Summary of the invention

[0008] The object of the present invention is to provide a high-toughness flame-retardant and heat-resistant plastic and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0009] To achieve the above object, the present invention provides the following technical solution: a high-toughness flame-retardant and heat-resistant plastic, wherein the raw materials thereof include the following components by weight: 20-32 parts of polycarbonate, 15-24 parts of polypropylene, 10-45 parts of high-density polyethylene, 16-25 parts of ABS resin, 4-9 parts of high-temperature nylon, 31-46 parts of degradable plastic filler, 9-11 parts of plasticizer, 1.5-9 parts of stabilizer, 3-12 parts of lubricant, 3.5-4.5 parts of toughening agent, 9.7-21.5 parts of synergistic flame retardant, 7-14 parts of thermal protective coating liquid, 0.5-3 parts of ester exchange inhibitor, and 1.5-2.6 parts of antioxidant;

[0010] The synergistic flame retardant is prepared by mixing decabromodiphenylethane and ultrafine calcium silicate in a mass ratio of (9-14): (1-3);

[0011] Synergistic flame retardants are added to polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon, biodegradable plastic fillers, plasticizers, stabilizers, lubricants, toughening agents, ester exchange inhibitors and antioxidants to form highly flame-retardant, highly tough and high-temperature resistant plastics that burn slower and have greater specific heat capacity than conventional plastics.

[0012] Preferably, the thermal protective coating liquid comprises glass microspheres and liquid epoxy resin in a molar mass ratio of (2-5):(11-14), and the particle size of the glass microspheres is 32-41 μm.

[0013] Preferably, the particle size of the degradable plastic filler is 5 to 12 μm, and the degradable plastic filler is one or more of montmorillonite, calcium carbonate or polyhydroxyalkanoate.

[0014] Preferably, the antioxidant is one or more of antioxidant 1076, antioxidant 168, antioxidant 2246 and DLTDP.

[0015] Preferably, the preparation method of the high-toughness flame-retardant and heat-resistant plastic is as follows:

[0016] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0017] Step S2: adding decabromodiphenylethane and ultrafine calcium silicate into a stirring tank in proportion and mixing them to prepare a synergistic flame retardant for later use; adding glass microspheres and liquid epoxy resin into a reaction kettle in proportion, mixing and stirring to prepare a thermal protective coating liquid for later use;

[0018] Step S3: adding dried polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon, stabilizer, lubricant, and transesterification inhibitor into an internal mixer in sequence and mixing them into a synthetic resin;

[0019] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add a plasticizer, a toughening agent, an antioxidant and a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0020] Step S5: adding the mixture obtained in step S3 into a twin-screw extruder, and adding the synergistic flame retardant into the twin-screw extruder, melt-blending to form a modified plastic strip with a thickness of 1.5-5 mm, and cooling and shaping the strip;

[0021] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0022] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0023] Step S8: performing a heat resistance test and a flame retardant grade test on the high-toughness flame retardant and heat-resistant plastic product prepared in step S7;

[0024] pass To calculate the specific heat capacity of the plastic,

[0025] Where: Q is the absorbed heat J

[0026] m is the mass of the object g

[0027] ΔT is the change in temperature after endothermic absorption.

[0028] Preferably, the step S3 further includes the following steps:

[0029] Step S31: Add dry high-density polyethylene, polypropylene, lubricant, stabilizer and ester exchange inhibitor into an internal mixer, and mix them at a temperature of 135 degrees Celsius for 38 minutes. Then add polycarbonate and ABS resin and continue to mix them at a temperature of 140-155 degrees Celsius for 18 minutes. Then add high-temperature nylon and mix them at a temperature of 140-155 degrees Celsius for 18 minutes.

[0030] Preferably, the step S4 further includes the following steps:

[0031] Step S41: first add the cooled synthetic resin and degradable plastic filler into a high-speed mixer, and mix for 54 minutes at a heating temperature of 245-255 degrees Celsius and a stirring speed of 255-265rpm. Then add an antioxidant to the high-speed mixer, and continue mixing for 16 minutes at a stirring speed of 255-265rpm. Then add a toughening agent, and continue mixing for 21 minutes at a stirring speed of 255-265rpm. Finally, add a plasticizer, and continue mixing for 11 minutes at a stirring speed of 255-265rpm.

[0032] Preferably, the step S5 further includes the following steps:

[0033] Step S51: The mixture is added from the first section discharge port of the twin-screw extruder, and the synergistic flame retardant is added from the fourth section side feeding port of the twin-screw extruder. The mixture is melt-blended for 21-24 minutes at a screw length-to-diameter ratio of (31 / 1-33 / 1) L / D, a rotation speed of 105-125 r / min, and a temperature of 177 degrees Celsius. The thickness of the die installed at the extrusion port is adjusted to 2-6 mm, and then the mixture is calendered by a calender and cooled to form a modified plastic strip with a thickness of 1.5-5 mm.

[0034] Preferably, in step S2, the mixing of decabromodiphenylethane and ultrafine calcium silicate is stirred at a speed of 94 rpm for 13 min, and the glass beads and liquid epoxy resin are reacted at a temperature of 55-75 degrees Celsius and a stirring speed of 100-105 rpm for 16 min.

[0035] Preferably, in step S4, the mass ratio of the synthetic resin, plasticizer, toughening agent, antioxidant and degradable plastic filler is (9-11):(3-4):(1-2):1:(15-17).

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention adds decabromodiphenylethane and ultrafine calcium silicate in a mass ratio of (1-3): (2-5) into a stirring tank, stirs for 13 minutes at a stirring speed of 94 rpm, and fully mixes the two to prepare a synergistic flame retardant for standby use. The synergistic flame retardant configured in proportion can effectively improve the flame retardancy level, will not cause harm to the environment when used, and the plastic made from it can be recycled, which can effectively improve the utilization efficiency of plastic products. The synergistic flame retardant is evenly blended with the mixture in proportion, so that the flame retardant performance of the mixture is effectively improved, and a modified plastic strip with high flame retardancy, high toughness and heat resistance is prepared, thereby improving the preparation efficiency.

[0038] 2. The present invention puts dried high-density polyethylene, polypropylene, lubricant, stabilizer and ester exchange inhibitor into an internal mixer, and mixes them for 38 minutes at a temperature of 135 degrees Celsius, so that the high-density polyethylene and polypropylene are easy to be evenly fused and distributed with the cooperation of the lubricant, and then passes cooling water to reduce the temperature to below 85 degrees Celsius, then polycarbonate and ABS resin are added thereto, and continue to mix them for 18 minutes at a temperature of 140-155 degrees Celsius, and then passes cooling water to reduce the temperature to below 85 degrees Celsius, and then adds high-temperature nylon thereto and mixes them for 18 minutes at a temperature of 140-155 degrees Celsius, so that the high-density polyethylene, polypropylene, polycarbonate, ABS resin and high-temperature nylon are fully mixed to prepare a mixed resin, and during the mixing process, the lubricant effectively reduces the raw material in the processing The friction of the materials increases the mixing efficiency of the raw materials. During the mixing process, the ester groups in the molecular chains of high-density polyethylene, polypropylene and polycarbonate will be exchanged. This ester exchange reaction may affect the performance of the synthetic resin produced. The ester exchange inhibitor is used to inhibit the occurrence of the ester exchange reaction. The stabilizer is used to improve the heat tolerance of high-density polyethylene, polypropylene and polycarbonate during processing, reduce the decomposition caused by heat, and improve the thermal stability of the synthetic resin. The synthetic resin prepared by mixing in proportion has significantly improved heat resistance, corrosion resistance, electrical insulation performance and toughness compared with a single component, and improves the defects of a single component. The single components used for mixing are non-toxic and odorless, and will not burden the environment. Therefore, the prepared synthetic resin has high toughness and heat resistance while being environmentally friendly.

[0039] 3. The present invention puts the prepared synthetic resin into a cooling device to quickly cool it to room temperature, then adds the cooled synthetic resin and a degradable plastic filler with a particle size of 5 to 12 μm into a high-speed mixer, and mixes for 54 minutes at a heating temperature of 245 to 255 degrees Celsius and a stirring speed of 255 to 265 rpm to allow the synthetic resin and the degradable plastic filler to be evenly mixed. The degradable plastic filler can improve the synthetic resin and rheological state, reduce the shrinkage rate of the synthetic resin, and effectively reduce the cost of the synthetic resin. Since the degradable plastic filler helps to reduce the impact of plastic production on the environment, it is convenient for discarded plastic products to be quickly degraded, reducing the burden of plastic waste on the environment. Then, an antioxidant is added to the high-speed mixer, and the mixing is continued for 16 minutes at a stirring speed of 255 to 265 rpm. The antioxidant can inhibit the synthesis of the synthetic resin. After being processed into plastic products, the quality of the fat changes due to oxidation, which effectively extends the service life of the plastic products. Then, a toughening agent is added, and mixing is continued for 21 minutes at a stirring speed of 255-265rpm to uniformly disperse the toughening agent in the synthetic resin. The toughening agent is then added to the synthetic resin and mixed to further enhance the toughness of the synthetic resin. Finally, a plasticizer is added thereto, and mixing is continued for 11 minutes at a stirring speed of 255-265rpm to uniformly disperse the plasticizer in the synthetic resin. The plasticizer is beneficial to increase the plasticity of the synthetic resin, which facilitates the subsequent preparation of the mixture into high-toughness, flame-retardant and heat-resistant plastic products. According to the above-mentioned order of addition, addition ratio and processing conditions, it is ensured that each raw material can be evenly dispersed in the synthetic resin, so that the prepared mixture has high toughness and heat resistance, thereby improving the preparation efficiency.

[0040] 4. The present invention puts the modified plastic strips into a pelletizer and cuts them into granules, cools and dries them, then adds the plastic granules into an injection molding machine and presses them into plastic products, then grinds the surface of the plastic product to smooth out the rough protrusions on the surface and increase the smoothness of the product, then sprays a thermal protective coating liquid on the polished plastic surface to form a 1 mm thermal protective coating on the surface, further improving the heat resistance of the plastic product, and the epoxy resin in the thermal protective coating liquid increases the bonding force between the glass microbeads and the plastic product, then sprays the modified flame retardant on the surface of the plastic product to form a 1.5 mm flame retardant coating to obtain a laminated coating, thereby improving the flame retardancy and heat resistance of the plastic product, thereby preparing a plastic product with high toughness, high flame retardancy and high heat resistance. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The invention provides a high-toughness flame-retardant and heat-resistant plastic, wherein the raw materials thereof include the following components by weight: 20-32 parts of polycarbonate, 15-24 parts of polypropylene, 10-45 parts of high-density polyethylene, 16-25 parts of ABS resin, 4-9 parts of high-temperature nylon, 31-46 parts of degradable plastic filler, 9-11 parts of plasticizer, 1.5-9 parts of stabilizer, 3-12 parts of lubricant, 3.5-4.5 parts of toughening agent, 9.7-21.5 parts of synergistic flame retardant, 7-14 parts of thermal protective coating liquid, 0.5-3 parts of ester exchange inhibitor, and 1.5-2.6 parts of antioxidant;

[0043] The synergistic flame retardant is prepared by mixing decabromodiphenylethane and ultrafine calcium silicate in a mass ratio of (9-14): (1-3);

[0044] Synergistic flame retardants are added to polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon, biodegradable plastic fillers, plasticizers, stabilizers, lubricants, toughening agents, transesterification inhibitors and antioxidants to form highly flame-retardant, highly tough and high-temperature resistant plastics, which have shorter burning times and greater specific heat capacity than conventional plastics;

[0045] The thermal protective coating liquid comprises glass microspheres and liquid epoxy resin in a molar mass ratio of (2-5):(11-14), and the particle size of the glass microspheres is 32-41 μm;

[0046] The preparation method of the high-toughness flame-retardant and heat-resistant plastic is as follows:

[0047] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0048] Step S2: adding decabromodiphenylethane and ultrafine calcium silicate into a stirring tank in proportion and mixing them to prepare a synergistic flame retardant for later use; adding glass microspheres and liquid epoxy resin into a reaction kettle in proportion, mixing and stirring to prepare a thermal protective coating liquid for later use;

[0049] In step S2, the mixing of decabromodiphenylethane and ultrafine calcium silicate is carried out at a stirring speed of 94 rpm for 13 min, and the glass microspheres and liquid epoxy resin are reacted for 16 min at a temperature of 55-75 degrees Celsius and a stirring speed of 100-105 rpm.

[0050] Furthermore, the drying temperature is adjusted to 90 degrees Celsius, and polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads are placed in the dryer in order and dried for 6-21 minutes to remove the residual moisture on the materials, thereby ensuring the processing quality of the subsequent preparation of high-toughness flame-retardant and heat-resistant plastics and avoiding the influence of moisture on the performance of the plastics. Then, decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank in a mass ratio of (1-3): (2-5), and stirred for 13 minutes at a stirring speed of 94 rpm to fully mix the two to prepare a synergistic flame retardant for use. The synergistic flame retardant is used in proportion in the preparation of plastics to effectively improve the flame retardancy of the plastics. Decabromodiphenylethane will decompose to produce hydrogen bromide during combustion, and hydrogen bromide can capture fire. High-energy free radicals in the flame zone, such as hydroxyl free radicals and hydrogen free radicals, inhibit the combustion chain reaction. At the same time, other bromides produced by the decomposition of decabromodiphenylethane will also participate in the flame retardant process to form non-combustible gases, dilute the oxygen concentration, and reduce the combustion rate. In addition, ultrafine calcium silicate will form a stable silicate protective layer on the plastic surface at high temperatures, effectively blocking heat transfer, reducing plastic thermal decomposition, and isolating the exchange of oxygen and combustible gases, thereby inhibiting further combustion of the plastic. No toxic substances will be produced during combustion, and no harm will be caused to the environment. The plastic made from it can be recycled, which can effectively improve the utilization efficiency of plastic products. Subsequently, a layer of synergistic flame retardant is sprayed on the surface of the prepared plastic product to form a flame retardant coating, which further improves the flame retardant properties of the plastic product.

[0051] Glass microbeads with a particle size of 32 to 41 μm and liquid epoxy resin are added into a reactor in a molar mass ratio of (2 to 5): (11 to 14). The reaction is stirred for 16 minutes at a heating temperature of 55 to 75 degrees Celsius and a stirring speed of 100 to 105 rpm to allow the two to be evenly mixed to prepare a thermal protective coating liquid for use. A 1 mm thermal protective coating layer is applied to the surface of the prepared plastic product to effectively improve the heat resistance of the plastic product and give the plastic product good thermal stability.

[0052] Step S3: adding dried polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon, stabilizer, lubricant, and transesterification inhibitor into an internal mixer in sequence and mixing them into a synthetic resin;

[0053] The step S3 further includes the following steps:

[0054] Step S31: Add dry high-density polyethylene, polypropylene, lubricant, stabilizer and ester exchange inhibitor into an internal mixer, and mix them at a temperature of 135 degrees Celsius for 38 minutes. Then add polycarbonate and ABS resin and continue to mix them at a temperature of 140-155 degrees Celsius for 18 minutes. Then add high-temperature nylon and mix them at a temperature of 140-155 degrees Celsius for 18 minutes.

[0055] Furthermore, the dried high-density polyethylene, polypropylene, lubricant, stabilizer and ester exchange inhibitor were put into an internal mixer, and the mixture was mixed for 38 minutes at a temperature of 135 degrees Celsius, so that the high-density polyethylene and polypropylene were easily evenly fused and distributed with the cooperation of the lubricant, and then cooling water was passed to reduce the temperature to below 85 degrees Celsius, and then polycarbonate and ABS resin were added thereto, and the mixing was continued for 18 minutes at a temperature of 140-155 degrees Celsius, and then cooling water was passed to reduce the temperature to below 85 degrees Celsius, and then high-temperature nylon was added thereto and mixed for 18 minutes at a temperature of 140-155 degrees Celsius, so that the high-density polyethylene, polypropylene, polycarbonate, ABS resin and high-temperature nylon were fully mixed to prepare a mixed resin, and during the mixing process, the lubricant effectively reduced the raw materials in the processing. The friction of the raw materials is increased, and the mixing efficiency of the raw materials is increased. During the mixing process, the ester groups in the molecular chains of high-density polyethylene, polypropylene and polycarbonate will be exchanged. This ester exchange reaction may affect the performance of the synthetic resin produced. The ester exchange inhibitor is used to inhibit the occurrence of the ester exchange reaction. The stabilizer is used to improve the heat tolerance of high-density polyethylene, polypropylene and polycarbonate during the processing, reduce the decomposition caused by heat, and improve the thermal stability of the synthetic resin. The synthetic resin prepared by mixing in proportion has significantly improved heat resistance, corrosion resistance, electrical insulation performance and toughness compared with the single component, and improves the defects of the single component. The single components used for mixing are non-toxic and odorless, and will not burden the environment. Therefore, the prepared synthetic resin has high toughness and heat resistance while being environmentally friendly.

[0056] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add a plasticizer, a toughening agent, an antioxidant and a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0057] The step S4 further includes the following steps:

[0058] Step S41: firstly add the cooled synthetic resin and the degradable plastic filler into a high-speed mixer, and mix them for 54 minutes at a heating temperature of 245-255 degrees Celsius and a stirring speed of 255-265 rpm, then add an antioxidant into the high-speed mixer, and continue to mix for 16 minutes at a stirring speed of 255-265 rpm, then add a toughening agent, and continue to mix for 21 minutes at a stirring speed of 255-265 rpm, and finally add a plasticizer, and continue to mix for 11 minutes at a stirring speed of 255-265 rpm;

[0059] In the step S4, the mass ratio of the synthetic resin, the plasticizer, the toughening agent, the antioxidant and the degradable plastic filler is (9-11): (3-4): (1-2): 1: (15-17);

[0060] The particle size of the degradable plastic filler is 5 to 12 μm, and the degradable plastic filler is one or more of montmorillonite, calcium carbonate or polyhydroxyalkanoate;

[0061] The antioxidant is one or more of antioxidant 1076, antioxidant 168, antioxidant 2246 and DLTDP.

[0062] Further, the prepared synthetic resin is placed in a cooling device to quickly cool it to room temperature, and then the cooled synthetic resin and a degradable plastic filler with a particle size of 5 to 12 μm are added to a high-speed mixer, and mixed for 54 minutes at a heating temperature of 245 to 255 degrees Celsius and a stirring speed of 255 to 265 rpm to allow the synthetic resin and the degradable plastic filler to be evenly mixed. The degradable plastic filler can improve the synthetic resin and rheological state, reduce the shrinkage rate of the synthetic resin, and effectively reduce the cost of the synthetic resin. Since the degradable plastic filler helps to reduce the impact of plastic production on the environment, it is convenient for discarded plastic products to be quickly degraded, reducing the burden of plastic waste on the environment. Then, an antioxidant is added to the high-speed mixer, and the mixing is continued for 16 minutes at a stirring speed of 255 to 265 rpm. The antioxidant can inhibit After being processed into plastic products, the synthetic resin undergoes a quality change due to oxidation, which effectively extends the service life of the plastic products. Then, a toughening agent is added, and mixing is continued for 21 minutes at a stirring speed of 255-265rpm to uniformly disperse the toughening agent in the synthetic resin. The toughening agent is then added to the synthetic resin and mixed to further enhance the toughness of the synthetic resin. Finally, a plasticizer is added thereto, and mixing is continued for 11 minutes at a stirring speed of 255-265rpm to uniformly disperse the plasticizer in the synthetic resin. The plasticizer is beneficial to increase the plasticity of the synthetic resin, so that the mixture is subsequently prepared into a high-toughness, flame-retardant, and heat-resistant plastic product. According to the above-mentioned order of addition, addition ratio, and processing conditions, it is ensured that each raw material can be evenly dispersed in the synthetic resin, so that the prepared mixture has high toughness and heat resistance.

[0063] Step S5: adding the mixture obtained in step S3 into a twin-screw extruder, and adding the synergistic flame retardant into the twin-screw extruder, melt-blending to form a modified plastic strip with a thickness of 1.5-5 mm, and cooling and shaping the strip;

[0064] The step S5 further includes the following steps:

[0065] Step S51: The mixture is added from the first section discharge port of the twin-screw extruder, and the synergistic flame retardant is added from the fourth section side feeding port of the twin-screw extruder. The mixture is melt-blended for 21-24 minutes at a screw length-to-diameter ratio of (31 / 1-33 / 1) L / D, a rotation speed of 105-125 r / min, and a temperature of 177 degrees Celsius. The thickness of the die installed at the extrusion port is adjusted to 2-6 mm, and then the mixture is calendered by a calender and cooled to form a modified plastic strip with a thickness of 1.5-5 mm.

[0066] Furthermore, the prepared mixture is added from the first section discharge port of the twin-screw extruder, and the synergistic flame retardant is added from the fourth section side feeding port of the twin-screw extruder. The mixture is melt-blended for 21-24 minutes under the conditions of a screw length-to-diameter ratio of (31 / 1-33 / 1) L / D, a rotation speed of 105-125 r / min, and a temperature of 177 degrees Celsius, so that the synergistic flame retardant and the mixture are fully and evenly blended. The mixture is extruded through a twin-screw extruder and then calendered through a calender to form a modified plastic strip with a thickness of 1.5-5 mm, which is then cooled and shaped. The synergistic plasticizer effectively improves the flame retardant properties of the mixture, and a modified plastic strip with high flame retardancy, high toughness and heat resistance is prepared, thereby improving the preparation efficiency.

[0067] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0068] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0069] Step S8: performing a heat resistance test and a flame retardant grade test on the high-toughness flame retardant and heat-resistant plastic product prepared in step S7;

[0070] pass To calculate the specific heat capacity of the plastic,

[0071] Where: Q is the absorbed heat J

[0072] m is the mass of the object g

[0073] ΔT is the change in temperature after endothermic absorption.

[0074] Further, the modified plastic strips are put into a pelletizer and cut into particles, and then cooled and dried. The plastic particles are then added to an injection molding machine and pressed into plastic products. The surface of the plastic product is then polished to smooth out the rough protrusions on the surface and increase the smoothness of the product. Then, a thermal protective coating liquid is sprayed on the polished plastic surface to form a 1 mm thermal protective coating layer on the surface. Due to its unique hollow structure, the glass microbeads can withstand the alternation of rapid heating and rapid cooling conditions without being affected by thermal shock. At the same time, its hollow structure enables the plastic to absorb energy when impacted, which can effectively improve the impact resistance of the plastic, further improve the heat resistance and impact resistance of the plastic product, and the epoxy resin in the thermal protective coating liquid increases the bonding force between the glass microbeads and the plastic product. Then, the modified flame retardant is sprayed on the surface of the plastic product to form a 1.5 mm flame retardant coating to obtain a laminated coating, thereby improving the flame retardancy and heat resistance of the plastic product.

[0075] Embodiment 1:

[0076] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0077] Step S2: decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank at a ratio of 9:1 and mixed to prepare a synergistic flame retardant for later use; glass microspheres with a particle size of 39 μm and 11 parts of liquid epoxy resin are added to a reaction kettle at a ratio of 2:11, and mixed and stirred to prepare a thermal protective coating liquid for later use;

[0078] Step S3: adding 21 parts of dried polycarbonate, 16 parts of polypropylene, 11 parts of high-density polyethylene, 17 parts of ABS resin, 5 parts of high-temperature nylon, 2.6 parts of stabilizer, 7 parts of lubricant, and 1.7 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0079] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 3.7 parts of a toughening agent, 2.0 parts of an antioxidant and 32 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0080] Step S5: adding 40 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 13 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-to-diameter ratio of 31 / 1L / D, a rotation speed of 110 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0081] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0082] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0083] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.0 J / (g·℃), the burning time is: 4 min, and the flame retardant grade is: V1.

[0084] Embodiment 2:

[0085] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0086] Step S2: adding decabromodiphenylethane and ultrafine calcium silicate into a stirring tank at a ratio of 9:1 and mixing them to prepare a synergistic flame retardant for later use; adding glass microspheres with a particle size of 39 μm and liquid epoxy resin into a reaction kettle at a ratio of 2:13, mixing and stirring to prepare a thermal protective coating liquid for later use;

[0087] Step S3: adding 21 parts of dried polycarbonate, 19 parts of polypropylene, 22 parts of high-density polyethylene, 19 parts of ABS resin, 5 parts of high-temperature nylon, 2.6 parts of stabilizer, 7 parts of lubricant, and 1.7 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0088] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 3.7 parts of a toughening agent, 2.0 parts of an antioxidant and 32 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0089] Step S5: adding 40 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 13 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-diameter ratio of 32 / 1L / D, a rotation speed of 110 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0090] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0091] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0092] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.1 J / (g·℃), the burning time is: 4 min, and the flame retardant grade is: V1.

[0093] Embodiment three:

[0094] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0095] Step S2: decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank in a ratio of 11:2 and mixed to prepare a synergistic flame retardant for later use; glass microspheres with a particle size of 37 μm and liquid epoxy resin are added to a reaction kettle in a ratio of 3:12, and mixed and stirred to prepare a thermal protective coating liquid for later use;

[0096] Step S3: adding 24 parts of dried polycarbonate, 16 parts of polypropylene, 14 parts of high-density polyethylene, 21 parts of ABS resin, 7 parts of high-temperature nylon, 3.8 parts of stabilizer, 7 parts of lubricant, and 1.9 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0097] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 4.3 parts of a toughening agent, 2.0 parts of an antioxidant and 32 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0098] Step S5: adding 52 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 17 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-to-diameter ratio of 31 / 1L / D, a rotation speed of 115 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0099] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0100] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0101] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.1 J / (g·℃), the burning time is: 3 min, and the flame retardant grade is: V1.

[0102] Embodiment 4:

[0103] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0104] Step S2: decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank in a ratio of 11:2 and mixed to prepare a synergistic flame retardant for later use; glass microspheres with a particle size of 37 μm and liquid epoxy resin are added to a reaction kettle in a ratio of 4:11, mixed and stirred to prepare a thermal protective coating liquid for later use;

[0105] Step S3: adding 29 parts of dried polycarbonate, 21 parts of polypropylene, 35 parts of high-density polyethylene, 19 parts of ABS resin, 5 parts of high-temperature nylon, 5 parts of stabilizer, 7 parts of lubricant, and 2.1 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0106] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 4.3 parts of a toughening agent, 2.2 parts of an antioxidant, and 41 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0107] Step S5: adding 59 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 19.5 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-diameter ratio of 33 / 1L / D, a rotation speed of 120 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0108] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0109] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0110] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.3J / (g·℃), the burning time is: 2min, and the flame retardant grade is: V0.

[0111] Embodiment five:

[0112] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0113] Step S2: decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank in a ratio of 13:2 and mixed to prepare a synergistic flame retardant for later use; glass microspheres with a particle size of 37 μm and liquid epoxy resin are added to a reaction kettle in a ratio of 4:11, mixed and stirred to prepare a thermal protective coating liquid for later use;

[0114] Step S3: adding 31 parts of dried polycarbonate, 19 parts of polypropylene, 43 parts of high-density polyethylene, 23 parts of ABS resin, 7 parts of high-temperature nylon, 7 parts of stabilizer, 7 parts of lubricant, and 2.3 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0115] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 4.3 parts of a toughening agent, 2.2 parts of an antioxidant, and 43 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0116] Step S5: adding 59 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 19.5 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-diameter ratio of 33 / 1L / D, a rotation speed of 120 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0117] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0118] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0119] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.9 J / (g·℃), the burning time is: 1 min, and the flame retardant grade is: V0.

[0120] Embodiment six:

[0121] Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes;

[0122] Step S2: decabromodiphenylethane and ultrafine calcium silicate are added to a stirring tank in a ratio of 13:1 and mixed to prepare a synergistic flame retardant for later use; glass microspheres with a particle size of 37 μm and liquid epoxy resin are added to a reaction kettle in a ratio of 3:11, and mixed and stirred to prepare a thermal protective coating liquid for later use;

[0123] Step S3: adding 29 parts of dried polycarbonate, 22 parts of polypropylene, 25 parts of high-density polyethylene, 21 parts of ABS resin, 5 parts of high-temperature nylon, 5 parts of stabilizer, 7 parts of lubricant, and 2.1 parts of transesterification inhibitor into an internal mixer in sequence, and mixing into a synthetic resin;

[0124] Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add 10 parts of a plasticizer, 3.7 parts of a toughening agent, 2.0 parts of an antioxidant and 41 parts of a degradable plastic filler into the high-speed mixer in proportion to obtain a mixture;

[0125] Step S5: adding 52 parts of the mixture obtained in step S3 into a twin-screw extruder, and adding 17 parts of a synergistic flame retardant into the twin-screw extruder, melt-blending at a screw length-diameter ratio of 32 / 1L / D, a rotation speed of 115 r / min, and a temperature of 177 degrees Celsius to form a modified plastic strip with a thickness of 2.5 mm, and cooling and shaping the strip;

[0126] Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment;

[0127] Step S7: adding the plastic particles in step S6 into an injection molding machine, die-casting into a plastic product according to the model, and polishing the plastic product, placing the polished plastic product into an automatic spraying machine, spraying the thermal protective coating liquid and the synergistic flame retardant on it in turn, and forming a 1mm thermal protective coating layer and a 1.5mm flame retardant coating layer on the surface of the plastic product to make a high-toughness flame-retardant and heat-resistant plastic;

[0128] Step S8: Perform a heat resistance test and a flame retardant grade test on the high-toughness flame retardant heat-resistant plastic product prepared in step S7, and calculate that the specific heat capacity of the high-toughness flame retardant heat-resistant plastic product is: 2.3 J / (g·℃), the burning time is: 3 min, and the flame retardant grade is: V1.

[0129] The proportion and performance test of high toughness flame retardant and heat resistant plastics are as follows:

[0130]

[0131] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A high-toughness flame-retardant and heat-resistant plastic, characterized in that: The raw materials include the following components by weight: 20-32 parts of polycarbonate, 15-24 parts of polypropylene, 10-45 parts of high-density polyethylene, 16-25 parts of ABS resin, 4-9 parts of high-temperature nylon, 31-46 parts of filler, 9-11 parts of plasticizer, 1.5-9 parts of stabilizer, 3-12 parts of lubricant, 3.5-4.5 parts of toughening agent, 9.7-21.5 parts of synergistic flame retardant, 7-14 parts of thermal protective coating liquid, 0.5-3 parts of ester exchange inhibitor, and 1.5-2.6 parts of antioxidant; The synergistic flame retardant is prepared by mixing decabromodiphenylethane and ultrafine calcium silicate in a mass ratio of (9-14): (1-3); The filler is one or more of montmorillonite, calcium carbonate or polyhydroxyalkanoate; The thermal protective coating liquid includes glass microspheres and liquid epoxy resin, and the molar mass ratio of the glass microspheres and liquid epoxy resin is (2-5): (11-14); The preparation method of the high-toughness flame-retardant and heat-resistant plastic is as follows: Step S1: sequentially placing polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon and glass beads into a drying machine for drying at a temperature of 90 degrees Celsius for 6-21 minutes; Step S2: adding decabromodiphenylethane and ultrafine calcium silicate into a stirring tank in proportion and mixing them to prepare a synergistic flame retardant for later use; adding glass microspheres and liquid epoxy resin into a reaction kettle in proportion, mixing and stirring to prepare a thermal protective coating liquid for later use; Step S3: adding dried polycarbonate, polypropylene, high-density polyethylene, ABS resin, high-temperature nylon, stabilizer, lubricant, and transesterification inhibitor into an internal mixer in sequence and mixing them into a synthetic resin; Step S4: After cooling the synthetic resin in S3 to room temperature, add it into a high-speed mixer, and add a plasticizer, a toughening agent, an antioxidant and a filler into the high-speed mixer in order according to a certain proportion to obtain a mixture; Step S5: adding the mixture obtained in step S4 into a twin-screw extruder, and adding the synergistic flame retardant into the twin-screw extruder, melt-blending to form a modified plastic strip with a thickness of 1.5-5 mm, and cooling and shaping the strip; Step S6: feeding the modified plastic strips shaped in step S5 into a pelletizer, cutting them into pellets, and performing cooling and drying treatment; Step S7: Add the plastic particles in step S6 into an injection molding machine, die-cast them into plastic products according to the model, and polish the plastic products. Put the polished plastic products into an automatic spraying machine, spray them with thermal protective coating liquid and synergistic flame retardant in turn, and form a 1mm thermal protective coating layer and a 1.5mm flame retardant coating on the surface of the plastic products to make high-toughness flame-retardant and heat-resistant plastics.

2. The high-toughness flame-retardant and heat-resistant plastic according to claim 1, characterized in that: The particle size of the glass beads is 32 to 41 μm.

3. The high-toughness flame-retardant and heat-resistant plastic according to claim 1, characterized in that: The particle size of the filler is 5 to 12 μm.

4. The high-toughness flame-retardant and heat-resistant plastic according to claim 1, characterized in that: The antioxidant is one or more of antioxidant 1076, antioxidant 168, antioxidant 2246 and DLTDP.

5. The high-toughness flame-retardant and heat-resistant plastic according to claim 1, characterized in that: The step S5 further includes the following steps: Step S51: The mixture is added from the first section discharge port of the twin-screw extruder, and the synergistic flame retardant is added from the fourth section side feeding port of the twin-screw extruder. The mixture is melt-blended for 21-24 minutes at a screw length-to-diameter ratio of 31 / 1-33 / 1, a rotation speed of 105-125r / min, and a temperature of 177 degrees Celsius. The thickness of the die installed at the extrusion port is adjusted to 2-6mm, and then the mixture is calendered by a calender and cooled to form a modified plastic strip with a thickness of 1.5-5mm.

6. The high-toughness flame-retardant and heat-resistant plastic according to claim 1, characterized in that: In step S2, the mixing of decabromodiphenylethane and ultrafine calcium silicate is carried out at a stirring speed of 94 rpm for 13 min, and the glass microspheres and liquid epoxy resin are reacted for 16 min at a temperature of 55-75 degrees Celsius and a stirring speed of 100-105 rpm.

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