CN114163744A

CN114163744A - Marine recycling and regenerating wear-resistant and heat-resistant display device shell

Info

Publication number: CN114163744A
Application number: CN202111304763.1A
Authority: CN
Inventors: 肖坚俊
Original assignee: Dongguan Guoheng Plastic Science & Technology Co ltd
Current assignee: Dongguan Guoheng Plastic Science & Technology Co ltd
Priority date: 2021-11-04
Filing date: 2021-11-04
Publication date: 2022-03-11
Anticipated expiration: 2041-11-04
Also published as: CN114163744B

Abstract

The invention provides a wear-resistant and heat-resistant display device shell for ocean recycling, which comprises a panel and a bottom plate, wherein the panel is a hollow frame body; the panel and the bottom plate comprise a plurality of mutual embedding parts, and the bottom plate is made of recycled marine polystyrene recycled materials. It has excellent shock resistance and wear and high temperature resistance.

Description

Marine recycling and regenerating wear-resistant and heat-resistant display device shell

The technical field is as follows: the invention relates to the field of display device shell manufacturing, in particular to a wear-resistant and heat-resistant display device shell recycled and regenerated in ocean.

Background art:

with the development and progress of science and technology, the life of human beings is continuously improved, the damage to the earth environment is increased day by day, and the environmental pollution is a very common problem. In recent years, scientists studying the earth environment have found that the pollution of the marine environment is becoming more serious, especially the destruction of the marine plastic wastes. According to the data, 880 million tons of plastic wastes are dumped into the ocean every year by human beings, and the ocean hardly has a precious clean soil. A scientific and technological daily newspaper article, "far exceed forecast of the quantity of plastic wastes in the Atlantic ocean", shows that 1200 ten thousand tons of micro plastic wastes are gathered in 200 m of seawater at the upper layer of the Atlantic ocean by scientific research teams in the ocean center of England. Today, the content of micro plastic wastes throughout the ocean area on the earth has far exceeded the budget value. The density of marine plastic waste is generally low, and the waste floats everywhere on water and is gathered like a large garbage field. However, it has been shown that marine organisms use plastic wastes as food, mixed with jellyfishes and the like. The plastic garbage can not be dissolved in the marine organism belly, and finally the organisms swell and die. In 2015, 52% of turtles predated plastic pollutants as reported in journal of global variation biology by university of queensland, australia. The intestinal canal of the turtle is blocked, the intestinal wall is perforated by garbage plastics and is infected by chemical substances in the plastics to die. A report from the national academy of sciences of the United states, which indicates that seabirds are at a very high risk of ingesting plastic. By 2050, 99% of seabird species (e.g., gull, sinewort) will be ingested with plastic. The problem of marine garbage pollution is a common problem faced by all mankind, and further deterioration of marine environmental pollution can be prevented only by continuously taking effective measures. Among them, the recycling of marine plastics is a difficult problem in research and conquering in various countries in the world at present.

Among them, polystyrene is one of the main pollutants of marine plastic wastes. Before the polystyrene is recycled, the recycled polystyrene has poor embrittlement performance due to long-term seawater immersion and other pollution corrosion, so that the performances such as impact resistance, tensile strength, fluidity, aging resistance, hardness and the like are reduced, and the polystyrene hardly has a utilization value compared with the polystyrene recycled after land consumption. And because the polystyrene under the marine atmospheric environment is destroyed and degraded and the polystyrene recovered by land consumption has great difference, the method is difficult to be applied to the regeneration method of the polystyrene recovered by land consumption.

The aging behavior of polystyrene in a 1-year natural environment experiment under the marine atmospheric condition of Qingdao is researched by Liu Shaotong and the like, and PS (polystyrene) is observed to be respectively 696cm^-1-756cm^-1、1450cm^-1-1600cm^-1、2850cm^-1-3100cm^-1Characteristic absorption bands of the range. But an inorganic impurity peak appears; PS at 1716cm^-1An obvious carbonyl characteristic absorption peak appears nearby, and the absorption peak intensity of the front side of the sample is higher than that of the back side of the sample, which indicates that the oxidation reaction promoted by illumination also occurs in the PS natural aging process; the ketone carbonyl absorption peak is also shown, which indicates that both the internal part and the terminal position of the carbon chain are oxidized to a certain degree, and probably because the electron-withdrawing effect of the benzene ring enables the oxygen molecule to have more energy to overcome the steric hindrance and oxidize the internal carbon atom, and meanwhile, the space advantage of the terminal carbon atom compared with the internal carbon atom is reduced due to the space effect of the benzene ring, so that the ketone/aldehyde substance generated by the oxidation of PS is higher, and the oxidation degree is also higher. Due to photo-oxidation aging reaction and water diffusion which occur in the aging process of the plastic, the oxidation reaction enables carbonyl groups to replace the original structure in the tissue, so that the stress is not uniform, and the local stress is not uniformLeading to a decrease in mechanical properties; the chemical bond of the substrate is also damaged by the penetration of water, defects are generated in the substrate, the load transfer effect of the substrate is reduced after the material is stressed, the mechanical property is reduced, and the compression, bending and lifting properties of the PS are greatly reduced. Meanwhile, the PS is not easy to generate surface defects compared with a rigid material, and tends to cause the surface appearance to tend to be uniform through the whole abrasion of natural weathering, so that the PS is easily influenced by ocean weathering.

The plum madder reports that the aging phenomena of three plastics, namely modified polyethylene, modified polypropylene and modified polystyrene, are researched in the typical natural climate environments of hot and humid oceans, cold villages and warm plateaus in China. Aiming at the contrast test of the modified plastic under a shed for 3 years and outdoor exposure in Wanning, Mohe and Lasa stations, the surface of the sample loses luster and becomes light in color, and microcracks with different degrees appear. Aging degree of the modified plastic: outdoor exposure > exposure under canopy, and to marine atmospheric environment more sensitive, ageing degree is from big to little order: wanning rassa, desert river; weather resistance of the modified plastic in Wanning: modified polyethylene > modified polypropylene > modified polystyrene, wherein the elongation at break and impact strength decrease by about 60% and 40%, respectively, for the modified polystyrene exposed to open air for 3 years in Wanning station, with the worst corrosion resistance. As the Wanning station is a damp and hot area with the most harsh environment in the 3 stations, and environmental factors such as strong light, high temperature, high humidity and increased salt fog have the greatest environmental effect on the modified plastics, the deposited salt does not directly participate in the aging of the plastics, but the salt particles are mainly attached to the defects on the surface of the material to be deliquesced in the whole test process, so that more moisture is introduced to the surface of the material, and the aging of the plastics is indirectly accelerated.

Scott lambert reported that the formation of nano-plastic particles, bubbles on the surface of the PS material, was measured during degradation of the disposable PS coffee cup lid. This indicates that the degradation process starts with a stable process of surface erosion resulting in the constant release of the nanoplastic into the surrounding solution. Bum GunKwon reported that beach and seawater taken from the pacific northeast and coastline of hawaii were investigated to determine the cause of global chemical contamination with Polystyrene (PS), and found that all samples contained Styrene Monomer (SM), Styrene Dimer (SD) and Styrene Trimer (ST), with the concentration profile of the styrene analogue being ST > SD > SM, indicating the presence of new global chemical contaminants derived from PS in the ocean and coastal areas. Studies also found that the distribution patterns of styrene analog concentrations of seawater and sand were different, indicating that beach is an excellent deposition site for reducing PS debris, which may originate from styrene analogs formed by chemical weathering and mechanical erosion of beach. The wurtz hall oceanographic institute reported that 5 commercially available polystyrene samples were placed in water and then exposed to simulated sunlight that was 3 times stronger than the equatorial sunlight, and as a result, it was found that the simulated sunlight partially oxidized all 5 samples to dissolved organic carbon. Researchers have calculated that in the natural environment ranging from 0 ° to 50 ° north latitude, i.e., in the wide area extending from the equator to the south canada border, it takes decades to complete this partial oxidation process, while additives can change the relative susceptibility of the photochemical oxidation of polystyrene, affecting the rate of degradation.

Therefore, the degradation of polystyrene recovered in the ocean and the polystyrene recovered after land consumption have significant differences in molecular structure and physical and chemical properties, and in the aspect of recycling, some special problems need to be solved. On the other hand, electronic products (3C products) such as electronic display device housings, which use a large amount of plastic materials, are one of the important sources for human consumption of plastics and waste generation. Because the utilization value of the polystyrene recovered from the ocean is very low, how to recycle the shells of the polystyrene electronic products recovered from the ocean makes the ocean garbage efficiently utilized, and the related research reports that the recycled products meet various performance requirements are not deep and sufficient, and the shells are still in the initial exploration stage. However, great progress is made in recycling marine plastic wastes in countries such as europe and the united states, and some electronic devices have begun to adopt marine recycled plastics to solve the increasingly serious marine plastic pollution. Therefore, in order to solve the current technical problem, the marine recycled plastic polystyrene needs to be further modified and recycled so as to obtain a polystyrene material suitable for electronic products (3C products), especially for display device housings.

The invention content is as follows:

the invention aims to obtain a wear-resistant and heat-resistant 3C product recycled and regenerated by ocean, in particular to a display device shell, and solves the problems of poor embrittlement performance, poor various performances and almost no utilization value of marine plastic polystyrene after recycling and separation, so that the plastic can be fully recycled. Meanwhile, the marine recycled and regenerated polystyrene material is suitable for 3C products, can further provide a marine recycled and regenerated polystyrene material for 3C products, and can be suitable for preparing housings of 3C products such as keyboards, mice and printers.

The invention is realized by the following technical scheme:

a wear-resistant and heat-resistant display device shell for ocean recycling comprises a panel and a bottom plate, wherein the panel is a hollow frame body; the panel and the bottom plate comprise a plurality of mutual embedding parts, and the bottom plate is made of recycled marine polystyrene recycled materials.

The recycled marine polystyrene regenerated material is prepared from the following raw materials in percentage by weight:

marine recycled polystyrene: 5 to 95 percent of the total weight of the mixture,

waste plastics consumption and polystyrene recovery: 5 to 10 percent of the total weight of the mixture,

polystyrene resin: 1 to 6 percent of the total weight of the mixture,

a crosslinking agent: 0.1 to 2 percent of the total weight of the mixture,

a toughening agent: 0.5 to 8 percent of the total weight of the mixture,

a compatilizer: 0.4 to 3 percent of the total weight of the mixture,

0.01 to 1.8 percent of antistatic agent,

nucleating agent: 0.5 to 3 percent of the total weight of the mixture,

lubricant: 0.2 to 2.5 percent of,

dispersing oil: 0.04 to 0.06 percent.

Wherein the cross-linking agent is one or more of BMI (bismaleamic acid), LPO (2, 5-dimethyl-2, 5-bis (tert-butylperoxy) -3-acetylene) and MTES (5-mercaptopropyltriethoxysilane).

The marine waste polystyrene plastic is influenced by the superposition of various physical factors, chemical factors and climatic environment factorsSuch as ocean waves, temperature, light, oxygen, ozone, variable valence metal particles and seawater, acids, bases and salts, and microorganisms, among others. In the preliminary aging research of the marine waste recycled polystyrene plastic, the molecular chain fracture is found to be very serious, and in the analysis of an infrared spectrogram, the marine recycled polystyrene is found to be 1450cm^-1-1600cm^-1、2850cm^-1-3100cm^-1The intensity of the characteristic absorption peak in the range is obviously reduced (see figure 1), and it can be seen that the polystyrene is obviously degraded, and meanwhile, the molecular weight is greatly reduced and the molecular weight distribution is greatly widened, so that the mechanical comprehensive performance is obviously reduced.

The invention is to further prepare 3C products, such as display shells, which have higher and higher performance requirements and more diversified requirements, and the display shells are easy to age due to high temperature generated by internal electronic components during working, and finally change the color of the display shells, and the shells have enough strength to protect the electronic components and are not easy to scratch. It is also generally required to have advantages of high temperature resistance, good heat insulation, light weight, static electricity prevention, good mechanical vibration resistance, small thermal expansion and the like. Thus, marine recycled polystyrene is difficult to simply regenerate suitable 3C products, especially display housings.

Based on the method, the aged and fractured molecular chains are connected by using an active cross-linking agent on the fractured molecular chains of the polystyrene, and under the action of the dispersed oil, the basic structure and the functions of the waste polystyrene plastic are recovered, and the molecular chains are increased. Although the impact resistance is improved by adding a crosslinking agent for recycling, the combination of properties is still insufficient for practical applications. Therefore, other substances are further added in the invention, and the regenerated material with more excellent comprehensive performance is obtained.

Further adding: the toughening agent is one or a mixture of acrylonitrile-butadiene copolymer (NBR), ethylene-propylene binary copolymer (EPR) and isobutylene rubber (IBR),

the compatilizer is one or a mixture of more of isocyanate, modified polyacrylate, acrylonitrile-styrene-acrylate copolymer-maleic anhydride graft copolymer (ASA-g-MAH),

the antistatic agent is one or a mixture of more of alcohol ether phosphate monoester, alkyl sodium sulfate and glycerol monopalmitate,

the nucleating agent is one or a mixture of more of sodium benzoate, di (benzylidene) sorbitol [ DBS ] and di (4-tert-butyl-benzoic acid) aluminum hydroxide,

the lubricant is one or a mixture of more of higher fatty alcohol, polytetrafluoroethylene wax and modified triglyceride,

dispersing oil, preferably silicone wax dispersing oil.

The raw materials are melted and extruded, the melting and extrusion temperature is 170-230 ℃, preferably 180-220 ℃, the melting and extrusion temperature is 175-195 ℃ in the first zone, 190-205 ℃ in the second zone, 205-215 ℃ in the third zone, 200-220 ℃ in the fourth zone, 195-205 ℃ in the fifth zone, 185-200 ℃ in the sixth zone and 190-210 ℃ in the head extrusion temperature.

The melt extrusion adopts double-screw extrusion, and the screw rotating speed is 300-500 r/min, preferably 350, 400 and 450 r/min.

The weight percentage of the raw materials is further preferably 50-90%, 60-90%, more preferably 65%, 70%, 75%, 80%, 85%,

the waste plastics-recycled polystyrene is more preferably 6%, 7%, 8%, 9%,

the polystyrene resin is preferably 2%, 3%, 4%, 5%,

the amount of the crosslinking agent is preferably 0.2% to 1.5%, more preferably 0.5%, 0.8%, 1%, 1.2%, further preferably bismaleamic acid (BMI), or preferably 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) -3-acetylene (LPO) or preferably 5-mercaptopropyltriethoxysilane, or preferably 0.5-1.2% bismaleamic acid (BMI) and 2, 5-dimethyl-2.5-bis (t-butylperoxy) -3-acetylene (LPO), or preferably 0.5 to 1.5% of 2, 5-dimethyl-2.5-bis (tert-butylperoxy) -3-acetylene (LPO) and 5-mercaptopropyltriethoxysilane, or preferably 0.5-1.2% bismaleamic acid (BMI) and 5-mercaptopropyltriethoxysilane.

The toughening agent is preferably used in an amount of 0.6% to 7%, or 0.8% to 6%, or preferably 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 5%, further preferably 1% to 3% of an acrylonitrile-butadiene copolymer (NBR), or 2.5% to 3.5% of an ethylene-propylene bipolymer (EPR), or 4% to 7.5% of an isobutylene rubber (IBR), or preferably 2% to 5.5% of an acrylonitrile-butadiene copolymer (NBR) and an ethylene-propylene bipolymer (EPR), or preferably 2% to 6% of an ethylene-propylene bipolymer (EPR) and an isobutylene rubber (IBR).

The amount of the compatibilizer is preferably 0.6%, 0.8%, 1%, 1.5%, 2%, 2.5%, further preferably 0.5 to 1% of isocyanate, or 1.5 to 2.5% of modified polyacrylate, or 0.5 to 1.5% of graft copolymer of acrylonitrile-styrene-acrylate copolymer-maleic anhydride (ASA-g-MAH), or preferably 0.5 to 2% of isocyanate and modified polyacrylate, or preferably 1 to 2.5% of graft copolymer of modified polyacrylate and acrylonitrile-styrene-acrylate copolymer-maleic anhydride, or preferably 0.5 to 2% of graft copolymer of isocyanate and acrylonitrile-styrene-acrylate copolymer-maleic anhydride (ASA-g-MAH).

In order to reduce the electrostatic hazard of plastics, the antistatic agent is further added, and then in the preparation method of the high-temperature melt extrusion, the antistatic agent is easily colored by heat in the processing process, and the mechanical strength of the product is greatly reduced, so that the regeneration and the utilization of the PS recovered from the sea are not facilitated. In order to improve the regeneration comprehensive performance of the marine recycled PS, the dosage of the antistatic agent is preferably 0.02%, 0.05%, 0.08%, 1%, 1.2%, 1.5%, and further preferably alcohol ether phosphate monoester, or preferably alkyl sodium sulfate, or preferably glycerol monopalmitate, or preferably alcohol ether phosphate monoester and alkyl sodium sulfate, or preferably alkyl sodium sulfate and glycerol monopalmitate, or preferably alcohol ether phosphate monoester and glycerol monopalmitate.

The nucleating agent is helpful for improving the mechanical property of the polystyrene, but different nucleating agents are added into PS in different nucleating modes and growth modes, different impact properties are different, some nucleating agents are easy to decompose at high temperature, or the dispersing properties are incompatible, so that the research shows that sodium benzoate, di (benzylidene) sorbitol (DBS) and di (4-tert-butyl-benzoic acid) aluminum hydroxide are adopted to regenerate the polystyrene recovered in the ocean, and a better effect is achieved. The nucleating agent is used in an amount of preferably 0.6%, 0.8%, 1%, 1.2%, 1.4%, 1.6%, 2%, 2.5%, 2.8%, further preferably sodium benzoate, or bis (benzylidene) sorbitol [ DBS ], or bis (4-tert-butyl-benzoic acid) aluminum hydroxide, or preferably sodium benzoate and bis (benzylidene) sorbitol, or preferably bis (benzylidene) sorbitol and bis (4-tert-butyl-benzoic acid) aluminum hydroxide, or preferably sodium benzoate and bis (4-tert-butyl-benzoic acid) aluminum hydroxide.

The amount of the lubricant used is preferably 0.3%, 0.4%, 0.5%, 0.7%, 0.8%, 1.0%, 1.5%, 1.8%, 2.0%, and more preferably a higher fatty alcohol, or a polytetrafluoroethylene wax, or a modified triglyceride, or preferably a higher fatty alcohol and a polytetrafluoroethylene wax, or preferably a polytetrafluoroethylene wax and a modified triglyceride.

The invention further provides a preparation method of the marine recycled polystyrene recycled regenerated material, which comprises the following steps of: the preparation steps are as follows:

(1) the PS recovered from the sea and the PS recovered from the waste plastics are dried,

(2) adding the dried marine plastic PS and the recycled PS and PS resin, the crosslinking agent, the toughening agent, the compatilizer and the antistatic agent into a stirring barrel, adding the dispersed oil after stirring, mixing and stirring,

(3) the nucleating agent and the lubricant are mixed and stirred,

(4) and adding the uniformly stirred mixture into a double screw for extrusion, feeding, melting and extruding, setting the temperature at 220 ℃ and the screw rotation speed at 500 rpm/min for 180-.

The invention further provides a regeneration preparation method of the polystyrene recovered from the ocean, which comprises the following steps,

(1) the polystyrene recovered from the ocean is crushed to the particle size of 0.2-5mm, then is cleaned and dried,

(2) uniformly mixing a cross-linking agent and the polystyrene obtained in the step (1) according to the mass ratio of 0.5-5: 100, adding dispersing oil, uniformly mixing, heating to a molten state, continuously melting and blending to enable the cross-linking agent and the polystyrene molecular chain recovered from the ocean to perform cross-linking reaction,

the cross-linking agent is one or a mixture of more of bismaleamic acid (BMI), 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) -3-acetylene (LPO) and 5-Mercaptopropyltriethoxysilane (MTES). Preference is given to bismaleamic acid (BMI), or preferably to 2, 5-dimethyl-2.5-bis (tert-butylperoxy) -3-acetylene (LPO) or preferably to 5-mercaptopropyltriethoxysilane, or to bismaleamic acid (BMI) and 2, 5-dimethyl-2.5-bis (tert-butylperoxy) -3-acetylene (LPO), or preferably to 2, 5-dimethyl-2.5-bis (tert-butylperoxy) -3-acetylene (LPO) and 5-mercaptopropyltriethoxysilane, or preferably to bismaleamic acid (BMI) and 5-mercaptopropyltriethoxysilane.

The drying in the step (1) is drying at the temperature of 60-100 ℃, preferably 80 ℃ and 90 ℃, and the drying time is 40-150min, preferably 60min and 120 min.

In the step (2), the melt blending is melt extrusion, the melt extrusion temperature is 170-.

And (3) further adding one or more of a toughening agent, a compatilizer, an antistatic agent, a nucleating agent and a lubricant.

Compared with the prior art, the invention has the advantages that:

1. the display device shell provided by the invention adopts the regenerated sea to recover PS, so that the display device shell has more superiority in various performances, the embrittlement performance is greatly improved, the performances such as impact resistance, tensile strength, fluidity, aging resistance and hardness are greatly improved, the display device shell with high strength, strong toughness and static resistance is obtained, and the display device shell also has better wear resistance and high temperature resistance.

2. Aiming at the characteristics of the polystyrene recovered from the sea, the molecular chain breakage is more serious than that of the polyethylene recovered from the common land, and the regeneration method of the polystyrene recovered from the land is difficult to simply apply. The recycling method of the invention well solves the problem of low recycling value of the marine recycled polystyrene, thereby effectively reducing and restraining the marine plastic pollution.

Description of the drawings:

FIG. 1: the invention ocean recovers PS and the invention regenerates the infrared spectrogram

The specific implementation mode is as follows:

the materials used in the practice of the invention are as follows,

the marine recycled plastic PS is obtained by marine salvage, the consumed waste plastic PS is obtained by a plastic garbage recycling plant, the PS resin is produced by Qimei practical products GmbH, LPO [2, 5-dimethyl-2.5-di (tert-butylperoxy) -3-acetylene ], MTES (5-mercaptopropyltriethoxysilane), NBR (acrylonitrile-butadiene copolymer), EPR (ethylene-propylene binary copolymer), IBR (isobutylene rubber), modified polyacrylate, ASA-g-MAH (acrylonitrile-styrene-acrylate copolymer-maleic anhydride graft copolymer), alcohol ether phosphate monoester, alkyl sodium sulfate, glycerol monopalmitate, DBS [ di (benzylidene) sorbitol ], di (4-tert-butyl-benzoic acid) aluminum hydroxide, higher aliphatic alcohol, The modified triglyceride is sold in Dongguan, BMI (bismaleamic acid) is produced by Shanghai Merlan Biotechnology Co., Ltd, isocyanate is produced by Hubei Jusheng technology Co., Ltd, polytetrafluoroethylene wax is produced by Zhongshan Langtsen Biotechnology Co., Ltd, and sodium benzoate is produced by Shanghai Yi En chemical technology Co., Ltd.

The instrumentation used in the practice of the invention is as follows,

MT36 twin screw extruder, nanjing mei zhilong; UN480a5 injection molding machine, mokuh et al; universal testing machine Shenzhen Meitess; rockwell hardness tester, Dongguan excels; impact tester, Dongguan high-speed rail; a melt flow coefficient tester, Dongguan high-speed rail; fourier transform infrared spectrometer, Tianjin hong Kong technology.

Example 1

A wear-resistant and heat-resistant display device shell for ocean recycling comprises a panel and a bottom plate, wherein the panel is of a hollow frame structure; the panel and the bottom plate are connected by four mutual embedding parts, wherein the bottom plate is made of recycled polystyrene recycled by ocean.

The specific marine recycled polystyrene recycled material is prepared by the following method:

1. the method comprises the steps of crushing and cleaning marine recycled polystyrene, drying the marine recycled polystyrene at 90 ℃ for 1-2 hours in advance, accurately weighing the marine recycled PS, the consumed waste PS, PS resin, BMI (bismaleamic acid), EPR (ethylene-propylene binary copolymer), isocyanate, glycerol monopalmitate, sodium benzoate, higher fatty acid and dispersed oil according to the formula shown in Table 2.

2. The preparation method comprises the steps of (1) preparing,

step one, putting the marine recycled plastic PS and the consumer waste plastic PS into an oven to be baked for 1-2 hours at the temperature of 90 ℃,

step two, adding the baked marine plastic PS, the consumed waste plastic PS, the PS resin, the BMI, the EPR, the isocyanate and the glycerol monopalmitate into a stirring barrel, stirring for 5min, adding the silicon wax dispersion oil, mixing and stirring for 5min,

step three, mixing sodium benzoate and higher fatty acid, adding into a stirring barrel, stirring for 10min,

and step four, adding the uniformly stirred mixture into a double screw for extrusion, feeding, melting and extruding, setting the temperature at 180 ℃ and 210 ℃, setting the rotating speed of the screw at 300 revolutions per minute, extruding and cooling, drying by drying air, and pelletizing to obtain the marine PS regenerated product.

The prepared recycled materials were subjected to determination of impact strength according to ASTM D256, tensile strength according to ASTM D638, flexural strength according to ASTM D790, Rockwell hardness according to ASTM D785, melt flow rate (melt index) according to ASTM D1238, and heat distortion temperature according to ASTM D648, respectively.

TABLE 1 melt extrusion temperature

Temperature of	A region	Two zones	Three zones	Four zones	Five zones	Six zones	Die head
								Setting up	180	190	200	210	190	180	190
Practice of	179	189	201	209	189	179	189

TABLE 2 formulation composition and regeneration Properties

The results show that various properties of the recycled material are improved along with the increase of the dosage of the auxiliary agent. When the dosage of the cross-linking agent, the toughening agent, the compatilizer and the like is obviously increased, although the melt rate is greatly improved, the impact property, the tensile strength, the hardness and the like are not obviously improved. Therefore, the formula 1 and the formula 2 have more excellent comprehensive performance.

Example 2

A wear-resistant and heat-resistant display device shell for ocean recycling comprises a panel and a bottom plate, wherein the panel is of a hollow frame structure; six mutual embedding parts are arranged between the panel and the bottom plate to connect the panel and the bottom plate, wherein the bottom plate is made of recycled marine polystyrene recycled materials.

1. the marine recycled polystyrene is dried at 90 ℃ for 1h in advance, sea sample recycled PS, consumed waste PS, PS resin, LPO (2, 5-dimethyl-2.5-bis (tert-butylperoxy) -3-acetylene), IBR (isobutylene rubber), modified polyacrylate, alcohol ether phosphate monoester, DBS (bis (benzylidene) sorbitol), polytetrafluoroethylene wax and silicon wax dispersion oil are accurately weighed according to a formula shown in a table 4.

2. The preparation method comprises the following steps:

step one, putting the marine recycled plastic PS and the consumer waste plastic PS into an oven to be baked for 2 hours at the temperature of 90 ℃,

step two, adding the baked marine plastic PS, the consumed waste plastic PS, the PS resin, the LPO, the IBR, the modified polyacrylate and the alcohol ether phosphate monoester into a stirring barrel, stirring for 5min, then adding the diffusion oil, mixing and stirring for 10min,

step three, mixing DBS and polytetrafluoroethylene wax, adding the mixture into a stirring barrel, stirring for 10min,

and step four, adding the uniformly stirred mixture into a double screw for extrusion, feeding, melting and extruding, setting the temperature at 180 ℃ and 210 ℃, setting the rotating speed of the screw at 350 revolutions per minute, extruding and cooling, drying by drying air, and pelletizing to obtain the material.

TABLE 3 melt extrusion temperature

Temperature of	A region	Two zones	Three zones	Four zones	Five zones	Six zones	Die head
								Setting up	190	200	210	210	200	190	200
Practice of	189	199	211	209	199	189	199

TABLE 4 formulation composition and regeneration Properties

The result shows that under the formula, the various properties of the recycled material are improved with the increase of the dosage of the auxiliary agent, but when the dosage of the compatilizer, the flexibilizer and the nucleating agent in the formula is obviously increased, the melt rate is greatly improved, the recycled material also has better tensile strength, but the properties such as impact strength, bending strength, heat distortion temperature and the like are obviously reduced. Therefore, the formula 5 and the formula 6 have more excellent comprehensive performance.

Example 3

1. sea sample recovered PS, consumed waste PS, PS resin, MTES (5-mercaptopropyltriethoxysilane), NBR (acrylonitrile-butadiene copolymer), ASA-g-MAH (acrylonitrile-styrene-acrylate copolymer-maleic anhydride graft copolymer), sodium alkyl sulfate, bis (4-tert-butyl-benzoic acid) aluminum hydroxide, modified triglyceride and silicone wax dispersed oil are accurately weighed according to a formula shown in Table 6 after the sea recovered polystyrene is dried at 90 ℃ in advance.

2. The preparation method comprises the steps of (1) preparing,

step two, adding the baked marine plastic PS, the consumed waste plastic PS, the PS resin, the MTES, the NBR, the ASA-g-MAH and the alkyl sodium sulfate into a stirring barrel, stirring for 5min, then adding the diffusion oil, mixing and stirring for 5min,

step three, mixing and adding the di (4-tert-butyl-benzoic acid) aluminum hydroxide and the modified triglyceride into a stirring barrel, stirring for 10min,

and step four, adding the uniformly stirred mixture into a double screw for extrusion, feeding, melting and extruding, setting the temperature at 180 ℃ and 210 ℃, setting the rotating speed of the screw at 300 revolutions per minute, extruding and cooling, drying by drying air, and pelletizing to obtain the material.

The recycled material was tested according to the method of example 1.

TABLE 5 melt extrusion temperature

Temperature of	A region	Two zones	Three zones	Four zones	Five zones	Six zones	Die head
								Setting up	190	200	210	210	200	190	200
Practice of	188	201	210	208	198	190	200

TABLE 6 formulation composition and regeneration Properties

The results show that under the formula, various properties of the recycled material are improved along with the increase of the dosage of the auxiliary agent, but when the dosage of the compatilizer, the antistatic agent and the nucleating agent in the formula is obviously increased, the impact strength, the tensile strength and the heat distortion temperature are obviously reduced. Therefore, the formulas 9, 10 and 11 have more excellent comprehensive properties.

Example 4

1. sea sample recovered PS, consumed waste PS, PS resin, MTES (5-mercaptopropyltriethoxysilane), NBR (acrylonitrile-butadiene copolymer), ASA-g-MAH (acrylonitrile-styrene-acrylate copolymer-maleic anhydride graft copolymer), sodium alkyl sulfate, bis (4-tert-butyl-benzoic acid) aluminum hydroxide, modified triglyceride and dispersed oil are accurately weighed according to a formula shown in Table 7 after the sea recovered polystyrene is dried at 90 ℃ in advance.

2. The preparation method comprises the steps of (1) preparing,

step two, adding the baked marine plastic PS, the consumed waste plastic PS, the PS resin, the crosslinking agent DCP, the toughening agent ACR, the compatilizer SMA and the antistatic agent GMS into a stirring barrel, stirring for 5min, then adding the silicon wax diffusion oil, mixing and stirring for 5min,

step three, mixing TMB-5 and methyl silicone oil, adding into a stirring barrel, stirring for 10min,

The recycled material was tested according to the method of example 1.

TABLE 7 formulation composition and regeneration Properties

The result shows that the comprehensive performance of the reclaimed material prepared by the formula does not meet the requirement of practical application.

Example 5

The bottom plates of the regenerated products prepared by the formula 1, the formula 5 and the formula 9, the bottom plate prepared by PS regeneration after land consumption recovery and the bottom plate prepared by polystyrene recovered from sea are put into an oven to be baked for 100min at 90 ℃, then injection molding is carried out to obtain test strips, the injection molding temperature is 180 ℃ and 210 ℃, and various performances and infrared spectrograms are tested according to the table 8. The results are compared as follows, Table 8 Performance test results

The preparation steps of the above PS recycled product backplane after land consumption (compare one) are similar to those of example 1, and mainly comprise a land recycled PS recycling formula: 100kg of land recycled PS, 16.45kg of PS resin, 5.21kg of calcium carbonate, 1.58kg of styrene butadiene rubber, 2.86kg of aluminate, 4.28kg of liquid crystal paraffin, 4.28kg of titanium oxide, 1.43kg of hindered phenol antioxidant 1010 and 4.28kg of triethyl citrate.

According to various test items, after the PS recovered from the sea is prepared by the regeneration method, the comprehensive performances of the PS recovered from the sea, such as impact strength, hardness and the like, are superior to those of the PS recovered from the land wastes. Also as shown in the figure, the PS after regeneration (formula 1) was at 1450cm in IR spectroscopy compared to the PS recovered from the ocean^-1-1600cm^-1、2850cm^-1-3100cm^-1The characteristic absorption peak in the range is obviously enhanced and is 1750cm^-1-2000cm^-1，1000cm^-1-1500cm^-1A new absorption peak appears, and the infrared spectrum of the cross-linked melt-blended extruded material of the formula 1 of the invention has obvious change, which indicates that the regenerated PS composition is changed. It can be seen that the base plate material of the present invention has more excellent properties.

Example 6

Since the current research report on the recovery of PS from the sea is not sufficient, the specific changes of the PS recovered from the sea in the composition and the microstructure are not fully clarified. In order to further explore the problems of the PS regeneration method of marine recovery, compared with the PS regeneration method after consumption and recovery on the land, the auxiliary agent of the invention is respectively used for trying to regenerate the PS after consumption and recovery on the land and observing the influence on the shell performance of the display device. See example 1 for test methods.

TABLE 9 regeneration Performance results for land-based PS recovery

As a result, the regeneration method of the present invention is not suitable for the preparation of PS backplane after the regeneration of land consumption recovery, which may be caused by the difference of the PS recycled on land in terms of the degree of fragmentation, degradation fragments and impurities contained therein, and is worthy of further study.

The above-described embodiments of the present invention are merely preferred examples, and are not intended to limit the embodiments of the present invention. It will be apparent to those skilled in the art that many modifications and variations can be made in the embodiments described above. The present invention need not be exemplified in this regard. Any modification, transformation or improvement within the scope of the claimed principles is intended to be within the scope of the claimed invention.

Claims

1. The wear-resistant and heat-resistant display device shell capable of being recycled and regenerated in the ocean is characterized by comprising a panel and a bottom plate, wherein the panel is a hollow frame body; the panel and the bottom plate comprise a plurality of mutual embedding parts, and the bottom plate is made of a polystyrene regeneration material recycled from the sea;

marine recycled polystyrene: 50 to 95 percent of the total weight of the mixture,

polystyrene resin: 1 to 6 percent of the total weight of the mixture,

a crosslinking agent: 0.1 to 2 percent of the total weight of the mixture,

a toughening agent: 0.5 to 8 percent of the total weight of the mixture,

a compatilizer: 0.4 to 3 percent of the total weight of the mixture,

0.01 to 1.8 percent of antistatic agent,

nucleating agent: 0.5 to 3 percent of the total weight of the mixture,

lubricant: 0.2 to 2.5 percent of,

dispersing oil: 0.04 to 0.06 percent;

2. The display housing of claim 1, wherein the toughening agent is one or more of acrylonitrile-butadiene copolymer (NBR), ethylene-propylene bipolymer (EPR), and isobutylene rubber (IBR).

3. The display housing of claim 1 wherein the compatibilizer is one or more of an isocyanate, a modified polyacrylate, an acrylonitrile-styrene-acrylate copolymer-maleic anhydride graft copolymer (ASA-g-MAH).

4. The display device enclosure of claim 1, wherein the antistatic agent is one or more of alcohol ether phosphate monoester, sodium alkyl sulfate, and glycerol monopalmitate.

5. A display housing according to claim 1, wherein the nucleating agent is one or more of sodium benzoate, bis (benzylidene) sorbitol [ DBS ], bis (4-tert-butyl-benzoic acid) aluminium hydroxide.

6. The display device cover of claim 1, wherein the lubricant is one or more of a mixture of higher aliphatic alcohols, polytetrafluoroethylene wax, modified triglycerides.

7. The display device housing of claim 1, wherein the polystyrene recycled material is prepared using a melt extrusion process.

8. The display device enclosure of claim 7, wherein the melt extrusion temperature is 170-230 ℃.

9. The display device housing of claim 7, wherein the melt extrusion is twin screw extrusion.