Weatherable abs alloy and method of making same

Abstract

The application discloses a weather-resistant ABS alloy and a preparation method thereof. The weather-resistant ABS alloy comprises the following components in parts by weight: 20-22 parts of ABS, 60-66 parts of modified polycarbonate, 4-6 parts of modified carbon nanotubes, 0.2-0.4 parts of an antioxidant, and 0.5-1.5 parts of an acidic lubricant. The modified polycarbonate is obtained by copolymerization of 2-(3,4-epoxycyclohexyl)ethyl methyl dimethoxysilane, octa-epoxycyclohexyl ethyl cage polysilsesquioxane, gamma-glycidyl ether oxygen propyl methyl diethoxysilane and carbon dioxide. The modified carbon nanotubes are obtained by modifying carbon nanotubes with isopropyl dioleate oxy (dioctyl phosphoric acid acyloxy titanate), isopropyl tri (dioctyl pyrophosphoric acid acyloxy) titanate and tetrabutyl titanate. The weather-resistant ABS alloy can effectively improve the agglomeration problem of the carbon nanotubes, uniformly disperse the carbon nanotubes in the weather-resistant ABS alloy, and further ensure the mechanical properties of the weather-resistant ABS alloy, and effectively improve the strength and toughness of the weather-resistant ABS alloy.

Description

Technical Field

[0001] This invention relates to the field of ABS material technology, specifically to a weather-resistant ABS alloy and its preparation method. Background Technology

[0002] Acrylonitrile-butadiene-styrene copolymer (ABS) is widely used in automobiles, home appliances, and electronic products due to its excellent mechanical properties, ease of processing, and good surface gloss. However, traditional ABS materials suffer from poor weather resistance. When exposed to ultraviolet light, humid and hot environments, or chemicals for a long time, they will age, discolor, or even crack, which severely limits their application in outdoor and harsh environments.

[0003] To overcome the aforementioned shortcomings, researchers have attempted to improve the weather resistance of ABS by adding other polymers. Polycarbonate (PC), as an engineering plastic with excellent transparency, heat resistance, and impact strength, has become one of the ideal choices for enhancing the weather resistance of ABS. Polycarbonate (abbreviated as PC) is a high-molecular-weight polymer containing carbonate groups in its molecular chain. Based on the structure of the ester groups, it can be classified into various types such as aliphatic, aromatic, and aliphatic-aromatic. However, the lower mechanical properties of aliphatic and aliphatic-aromatic polycarbonates limit their application in engineering plastics; currently, only aromatic polycarbonates have achieved industrial production. Furthermore, the rigid benzene ring structure of aromatic polycarbonates restricts the orientation between PC molecular chains. Under external force, the orientation is not easily relaxed, and the residual internal stress in the molecular chains is difficult to eliminate. This internal stress is frozen, making PC products prone to stress cracking. PC also exhibits poor impact performance below 0°C, with its impact strength at low temperatures being significantly lower than at room temperature. Therefore, it is necessary to improve the low-temperature toughness of PC. In order to make the modified ABS material suitable for applications with strict fire protection requirements, such as internal components of public transportation vehicles, the flame retardancy of ABS alloys also needs to be addressed.

[0004] In recent years, carbon nanotubes (CNTs) have also attracted widespread attention as a novel nanofiller. CNTs possess extremely high aspect ratios and excellent mechanical properties; adding even small amounts can significantly improve the strength, modulus, and conductivity of the matrix material. When combined with ABS / PC composite systems, they can not only toughen the ABS / PC composite system and further optimize the material's physical and mechanical properties, but also endow the material with certain electromagnetic shielding functions, expanding its application range.

[0005] However, while adding PC and CNTs can significantly improve the overall performance of ABS materials, it also brings some technical challenges. Although carbon nanotubes can significantly improve certain properties of the material, their extremely high surface activity makes them prone to aggregation. This not only affects the uniformity of the composite material but may also become stress concentration points within the material, thus reducing its toughness.

[0006] Therefore, the applicant provides a weather-resistant ABS alloy and its preparation method to overcome the aforementioned defects. Summary of the Invention

[0007] The purpose of this invention is to provide a weather-resistant ABS alloy and its preparation method to solve the technical problems mentioned in the background section.

[0008] The technical solution to achieve the objective of this invention is:

[0009] A weather-resistant ABS alloy, by weight, comprises the following raw material components: 20-22 parts by weight of ABS, 60-66 parts by weight of modified polycarbonate, 4-6 parts by weight of modified carbon nanotubes, 0.2-0.4 parts by weight of antioxidant, and 0.5-1.5 parts by weight of acidic lubricant.

[0010] Furthermore, the antioxidant used is antioxidant 168.

[0011] Furthermore, the modified polycarbonate is obtained by copolymerization of epoxy monomers and carbon dioxide.

[0012] Furthermore, the epoxy monomer is a composition of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane.

[0013] Furthermore, the modified carbon nanotubes are obtained by modifying carbon nanotubes with a titanate coupling agent.

[0014] Furthermore, the titanate coupling agent is a combination of isopropyl dioleate oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate.

[0015] This invention also provides a method for preparing weather-resistant ABS alloy, comprising the following preparation steps:

[0016] (1) Weigh and prepare the materials according to the following weight parts and raw material components: 20-22 parts by weight of ABS, 60-66 parts by weight of modified polycarbonate, 4-6 parts by weight of modified carbon nanotubes, 0.2-0.4 parts by weight of antioxidant, and 0.5-1.5 parts by weight of acidic lubricant;

[0017] (2) Mix 60-66 parts by mass of modified polycarbonate and 60-66 parts by mass of benzene in a reaction vessel, stir at high speed, and then add a benzene suspension of modified carbon nanotubes dropwise. The benzene suspension of modified carbon nanotubes contains 4-6 parts by mass of modified carbon nanotubes and 60-66 parts by mass of benzene. After the addition is complete, continue stirring for 2.8-3.2 hours. The entire addition and reaction process should be carried out under reduced pressure distillation, followed by rotary evaporation and drying to obtain the initial mixture.

[0018] (3) Dry 20-22 parts by weight of ABS for 24 hours, then mix it evenly with the initial mixture, 0.2-0.4 parts by weight of antioxidant and 0.5-1.5 parts by weight of acidic lubricant, and add it to the extruder for extrusion granulation. Then dry the obtained particles overnight to obtain weather-resistant ABS alloy.

[0019] Further, the preparation steps of the modified polycarbonate are as follows: epoxy monomer, catalyst SalenCoCl and co-catalyst PPNCl are added to a pre-dried high-pressure reactor, and CO2 at 3-4 MPa is introduced at 25°C. The reactor is stirred at 150-250 rpm for 24 h at 25°C to obtain the modified polycarbonate; wherein, the epoxy monomer is 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, or γ-glycidyl etheroxypropylmethyldiethoxysilane.

[0020] Furthermore, the mass ratio of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane is 10:4 to 6:84 to 86; the mass ratio of epoxy monomer to catalyst SalenCoCl and co-catalyst PPNCl is 990 to 1010:1:1.

[0021] Further, the preparation steps of the modified carbon nanotubes are as follows: 49-51 parts by mass of ferrous sulfate heptahydrate are dissolved in 200 parts by mass of distilled water, followed by 5 parts by mass of multi-walled carbon nanotubes, ultrasonically vibrated for 25-35 min, then 148-152 parts by mass of hydrogen peroxide are added, and the mixture is stirred for 11.5-12.5 h. The mixture is then filtered under reduced pressure, washed repeatedly with distilled water until the filtrate is neutral, and then dried in a 70°C drying oven for 24 h to obtain hydroxylated carbon nanotubes. 3 parts by mass of hydroxylated carbon nanotubes, 160 parts by mass of ethanol, and 19-21 parts by mass of titanate coupling agent are mixed and placed in an ultrasonic cleaner for ultrasonic vibration for 25-35 min. After ultrasonication, the mixture is reacted at 74-76°C with stirring for 3-5 h. After the reaction, the mixture is naturally cooled to room temperature, then filtered under reduced pressure, and washed repeatedly with anhydrous ethanol to remove unreacted titanate coupling agent from the reaction solution. Finally, the mixture is dried in a 70°C drying oven for 12 h to obtain modified carbon nanotubes.

[0022] Further, the titanate coupling agent includes isopropyl dioleate oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate; the mass ratio of isopropyl dioleate oxy (dioctyl phosphoyl oxy) titanate, isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate is 1:1:1.5 to 2.5.

[0023] By adopting the above technical solution, the present invention has the following beneficial effects:

[0024] (1) The raw material components of the weather-resistant ABS alloy of the present invention include ABS, modified polycarbonate, modified carbon nanotubes, antioxidants, and acidic lubricants; wherein, the modified carbon nanotubes are obtained by modifying carbon nanotubes with titanate coupling agents, which can effectively improve the agglomeration problem of carbon nanotubes, uniformly disperse carbon nanotubes in the weather-resistant ABS alloy, thereby ensuring the mechanical properties of the weather-resistant ABS alloy and effectively improving the strength and toughness of the weather-resistant ABS alloy.

[0025] (2) The modified polycarbonate of the present invention is obtained by copolymerizing 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, γ-glycidyl etheroxypropylmethyldiethoxysilane with carbon dioxide to obtain a polysiloxane-polycarbonate block copolymer (Si-PC) with a dendritic structure. Polysiloxane itself has natural flame retardancy, the decomposition gas produced during combustion is non-toxic, and it has excellent weather resistance, high and low temperature resistance and dielectric properties. At the same time, it has extremely low surface energy, which helps to improve the mobility of polymer chain segments, thus exhibiting excellent impact resistance under low temperature conditions. However, the compatibility between polysiloxane and polycarbonate is poor, and direct mixing will lead to the separation of the two phases, affecting the material properties. By block copolymerizing the above-mentioned specific siloxane monomers with PC, this problem can be effectively solved, so that the polysiloxane is uniformly dispersed in the PC matrix, which not only improves the flame retardancy and low temperature toughness of PC.

[0026] (3) In this invention, modified polycarbonate with a certain dendritic structure is first premixed with modified carbon nanotubes, and then ABS, antioxidants, and acidic lubricants are added for compounding. During this process, the modified carbon nanotubes, antioxidants, and acidic lubricants can disperse into the cavities formed by the dendritic modified polycarbonate, while ABS can penetrate into these cavities and form physical crosslinks with the dendritic modified polycarbonate, thereby initially increasing the compatibility between the modified polycarbonate and ABS. The modified carbon nanotubes are not condensed. The Ti-OH groups can react with the unreacted silanol groups in the dendritic modified polycarbonate to generate polytitanium siloxane, which firmly grafts the modified carbon nanotubes onto the modified polycarbonate, forming stable chemical bonds. This process not only strengthens the bond between the modified carbon nanotubes and the modified polycarbonate, but also further promotes the compatibility between the modified polycarbonate and ABS through the good compatibility between the modified carbon nanotubes and ABS. The resulting weather-resistant ABS alloy exhibits significantly improved flame retardant properties, mechanical properties, and weather resistance. Detailed Implementation

[0027] To better understand the above technical solution, the following will provide a detailed explanation of the technical solution in conjunction with specific implementation methods.

[0028] The following embodiments are only used to illustrate the technical solutions of the present invention more clearly, and should not be used to limit the scope of protection of the present invention.

[0029] The following are the raw material components for the examples and comparative examples:

[0030] The ABS used is PA-757, with a density of 1040 kg / m³. 3 Chi Mei Industrial Co., Ltd.

[0031] Multi-walled carbon nanotubes (MWCNTs): TNM3, outer diameter 10–20 nm, mass fraction >98%, Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences.

[0032] Acidic lubricant: AC 540A, the main component of which is ethylene-acrylic acid copolymer, Honeywell International.

[0033] The catalyst SalenCoCl and the co-catalyst PPNCl were both sourced from Shanghai Anaiji Chemical Co., Ltd., and were (R,R)-(-)-N,N'-bis(3,5-di-tert-butylsalicyl)-1,2-cyclohexyldiaminecobalt and (bis-(triphenylphosphine)ammonium chloride), respectively.

[0034] The PC used is the PC-110 from Chi Mei Industrial Co., Ltd.

[0035] All other raw materials are commercially available.

[0036] Example 1

[0037] A method for preparing a weather-resistant ABS alloy includes the following preparation steps:

[0038] (1) Weigh and prepare the materials according to the following weight parts and raw material components: 20 parts by weight of ABS, 60 parts by weight of modified polycarbonate, 4 parts by weight of modified carbon nanotubes, 0.2 parts by weight of antioxidant, and 0.5 parts by weight of acidic lubricant;

[0039] (2) Mix 60 parts by mass of modified polycarbonate and 60 parts by mass of benzene in a reaction vessel and stir at 1000 rpm for 25 min. Then add the benzene suspension of modified carbon nanotubes dropwise at 0.15 mL / min. The benzene suspension of modified carbon nanotubes contains 4 parts by mass of modified carbon nanotubes and 60 parts by mass of benzene. After the addition is complete, continue stirring for 2.8 h. The entire addition and reaction process should be carried out under reduced pressure distillation. Then, rotary evaporation and drying are performed to obtain the initial mixture.

[0040] (3) 20 parts by mass of ABS were dried at 90°C for 24 hours. Then, they were mixed evenly with the initial mixture, 0.2 parts by mass of antioxidant and 0.5 parts by mass of acidic lubricant and added to the extruder for extrusion granulation. The extrusion temperature from zone 1 to zone 10 was 80, 120, 230, 240, 240, 240, 240, 240, 240, 240, 240, and the main machine speed was 500 r / min. The resulting particles were then dried overnight at 100°C to obtain weather-resistant ABS alloy.

[0041] The preparation steps of the modified polycarbonate are as follows: Epoxy monomers, catalyst SalenCoCl, and co-catalyst PPNCl are added to a pre-dried high-pressure reactor, and 3MPa CO2 at 25°C is introduced. The reactor is stirred at 150 rpm for 24 hours at 25°C to obtain the modified polycarbonate. The epoxy monomers used are 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane. The mass ratio of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane is 10:4:86. The mass ratio of epoxy monomers to catalyst SalenCoCl and co-catalyst PPNCl is 990:1:1.

[0042] The preparation steps of the modified carbon nanotubes are as follows: 49 parts by mass of ferrous sulfate heptahydrate are dissolved in 200 parts by mass of distilled water, then 5 parts by mass of multi-walled carbon nanotubes are added, and the mixture is ultrasonically vibrated for 25 min. Then 148 parts by mass of hydrogen peroxide are added, and the mixture is stirred at 300 rpm for 11.5 h. The mixture is then filtered under reduced pressure, washed repeatedly with distilled water until the filtrate is neutral, and then dried in a 70℃ drying oven for 24 h to obtain hydroxylated carbon nanotubes. 3 parts by mass of hydroxylated carbon nanotubes, 160 parts by mass of ethanol, and 19 parts by mass of titanate coupling agent are mixed and placed in an ultrasonic cleaner for ultrasonic vibration for 25 min. After ultrasonication, the mixture is then... The reaction was carried out at 74℃ and 800rpm for 3 hours. After the reaction, the mixture was naturally cooled to room temperature, then filtered under reduced pressure and washed repeatedly with anhydrous ethanol to remove unreacted titanate coupling agent from the reaction solution. The mixture was then dried in a 70℃ drying oven for 12 hours to obtain modified carbon nanotubes. The titanate coupling agent included isopropyl dioleoyl oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate. The mass ratio of isopropyl dioleoyl oxy (dioctyl phosphoyl oxy) titanate, isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate was 1:1:1.5.

[0043] Example 2

[0044] A method for preparing a weather-resistant ABS alloy includes the following preparation steps:

[0045] (1) Weigh and prepare the materials according to the following weight parts and raw material components: 21 parts by weight of ABS, 63 parts by weight of modified polycarbonate, 5 parts by weight of modified carbon nanotubes, 0.3 parts by weight of antioxidant, and 1 part by weight of acidic lubricant.

[0046] (2) Mix 63 parts by mass of modified polycarbonate and 63 parts by mass of benzene in a reaction vessel and stir at 2000 rpm for 30 min. Then add the benzene suspension of modified carbon nanotubes dropwise at 0.15 mL / min. The benzene suspension of modified carbon nanotubes contains 5 parts by mass of modified carbon nanotubes and 63 parts by mass of benzene. After the addition is complete, continue stirring for 3 h. The entire addition and reaction process should be carried out under reduced pressure distillation. Then, rotary evaporation and drying are performed to obtain the initial mixture.

[0047] (3) 21 parts by mass of ABS were dried at 90°C for 24 hours. Then, they were mixed evenly with the initial mixture, 0.3 parts by mass of antioxidant, and 1 part by mass of acidic lubricant and added to the extruder for extrusion granulation. The extrusion temperature from zone 1 to zone 10 was 80, 120, 230, 240, 240, 240, 240, 240, 240, 240, 240, and the main machine speed was 550 r / min. The resulting particles were then dried overnight at 100°C to obtain weather-resistant ABS alloy.

[0048] The preparation steps of the modified polycarbonate are as follows: Epoxy monomers, catalyst SalenCoCl, and co-catalyst PPNCl are added to a pre-dried high-pressure reactor, and 3.5 MPa CO2 at 25°C is introduced. The reactor is stirred at 200 rpm for 24 h at 25°C to obtain the modified polycarbonate. The epoxy monomers used are 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane. The mass ratio of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane is 10:5:85. The mass ratio of epoxy monomers to catalyst SalenCoCl and co-catalyst PPNCl is 1000:1:1.

[0049] The preparation steps of the modified carbon nanotubes are as follows: 50 parts by mass of ferrous sulfate heptahydrate are dissolved in 200 parts by mass of distilled water, then 5 parts by mass of multi-walled carbon nanotubes are added, and the mixture is ultrasonically vibrated for 30 min. Then 150 parts by mass of hydrogen peroxide are added, and the mixture is stirred at 400 rpm for 12 h. The mixture is then filtered under reduced pressure, washed several times with distilled water until the filtrate is neutral, and then dried in a 70℃ drying oven for 24 h to obtain hydroxylated carbon nanotubes. 3 parts by mass of hydroxylated carbon nanotubes, 160 parts by mass of ethanol, and 20 parts by mass of titanate coupling agent are mixed and placed in an ultrasonic cleaner, where they are ultrasonically vibrated for 30 min. After ultrasonication, the mixture is then placed in a 7℃ drying oven. The reaction was carried out at 5℃ and 1000rpm for 4 hours. After the reaction, the mixture was naturally cooled to room temperature, then filtered under reduced pressure and washed repeatedly with anhydrous ethanol to remove unreacted titanate coupling agent from the reaction solution. The mixture was then dried in a 70℃ drying oven for 12 hours to obtain modified carbon nanotubes. The titanate coupling agent included isopropyl dioleoyl oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate. The mass ratio of isopropyl dioleoyl oxy (dioctyl phosphoyl oxy) titanate, isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate was 1:1:2.

[0050] Example 3

[0051] A method for preparing a weather-resistant ABS alloy includes the following preparation steps:

[0052] (1) Weigh and prepare the materials according to the following weight parts and raw material components: 22 parts by weight of ABS, 66 parts by weight of modified polycarbonate, 6 parts by weight of modified carbon nanotubes, 0.4 parts by weight of antioxidant, and 1.5 parts by weight of acidic lubricant;

[0053] (2) Mix 66 parts by mass of modified polycarbonate and 66 parts by mass of benzene in a reaction vessel and stir at 3000 rpm for 35 min. Then add the benzene suspension of modified carbon nanotubes dropwise at 0.15 mL / min. The benzene suspension of modified carbon nanotubes contains 6 parts by mass of modified carbon nanotubes and 66 parts by mass of benzene. After the addition is complete, continue stirring for 3.2 h. The entire addition and reaction process should be carried out under reduced pressure distillation. Then, rotary evaporation and drying are performed to obtain the initial mixture.

[0054] (3) 22 parts by mass of ABS were dried at 90°C for 24 hours. Then, they were mixed evenly with the initial mixture, 0.4 parts by mass of antioxidant and 1.5 parts by mass of acidic lubricant and added to the extruder for extrusion granulation. The extrusion temperature from zone 1 to zone 10 was 80, 120, 230, 240, 240, 240, 240, 240, 240, 240, 240, and the main machine speed was 600 r / min. The resulting particles were then dried overnight at 100°C to obtain weather-resistant ABS alloy.

[0055] The preparation steps of the modified polycarbonate are as follows: Epoxy monomers, catalyst SalenCoCl, and co-catalyst PPNCl are added to a pre-dried high-pressure reactor, and 4 MPa CO2 at 25°C is introduced. The reactor is stirred at 250 rpm for 24 h at 25°C to obtain the modified polycarbonate. The epoxy monomers used are 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane. The mass ratio of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane is 10:6:84. The mass ratio of epoxy monomers to catalyst SalenCoCl and co-catalyst PPNCl is 1010:1:1.

[0056] The preparation steps of the modified carbon nanotubes are as follows: 51 parts by mass of ferrous sulfate heptahydrate are dissolved in 200 parts by mass of distilled water, then 5 parts by mass of multi-walled carbon nanotubes are added, and the mixture is ultrasonically vibrated for 35 min. Then 152 parts by mass of hydrogen peroxide are added, and the mixture is stirred at 500 rpm for 12.5 h. The mixture is then filtered under reduced pressure, washed repeatedly with distilled water until the filtrate is neutral, and then dried in a 70℃ drying oven for 24 h to obtain hydroxylated carbon nanotubes. 3 parts by mass of hydroxylated carbon nanotubes, 160 parts by mass of ethanol, and 21 parts by mass of titanate coupling agent are mixed and placed in an ultrasonic cleaner, where they are ultrasonically vibrated for 35 min. After ultrasonication, the mixture is then... The reaction was carried out at 6℃ and 1200rpm for 5h. After the reaction, the mixture was naturally cooled to room temperature, then filtered under reduced pressure and washed repeatedly with anhydrous ethanol to remove unreacted titanate coupling agent from the reaction solution. The mixture was then dried in a 70℃ drying oven for 12h to obtain modified carbon nanotubes. The titanate coupling agent included isopropyl dioleoyl oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate. The mass ratio of isopropyl dioleoyl oxy (dioctyl phosphoyl oxy) titanate, isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate was 1:1:2.5.

[0057] Comparative Example 1

[0058] The only difference between Comparative Example 1 and Example 2 is that, by weight, the weather-resistant ABS alloy comprises: 21 parts by weight of ABS, 63 parts by weight of PC, 5 parts by weight of modified carbon nanotubes, 0.3 parts by weight of antioxidant, and 1 part by weight of acidic lubricant; the remaining steps and components are the same as in Example 2.

[0059] Comparative Example 2

[0060] The only difference between Comparative Example 2 and Example 2 is that, by weight, the weather-resistant ABS alloy comprises: 21 parts by weight of ABS, 63 parts by weight of modified polycarbonate, 5 parts by weight of carbon nanotubes, 0.3 parts by weight of antioxidant, and 1 part by weight of acidic lubricant; the remaining steps and components are the same as in Example 2.

[0061] Comparative Example 3

[0062] The only difference between Comparative Example 3 and Example 2 is that the modified polycarbonate is obtained by mixing PC and polysiloxane; the remaining steps and components are the same as in Example 2.

[0063] Comparative Example 4

[0064] The only difference between Comparative Example 4 and Example 2 is that the modified polycarbonate is obtained by copolymerization of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, γ-glycidyl etheroxypropylmethyldiethoxysilane and carbon dioxide; the remaining steps and components are the same as in Example 2.

[0065] Comparative Example 5

[0066] The only difference between Comparative Example 5 and Example 2 is that the modified polycarbonate is obtained by copolymerization of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, octaepoxycyclohexylethyl cage polysilsesquioxane, γ-glycidyl etheroxypropyltriethoxysilane and carbon dioxide; the remaining steps and components are the same as in Example 2.

[0067] Comparative Example 6

[0068] The only difference between Comparative Example 6 and Example 2 is that the raw material components are directly mixed and granulated, specifically:

[0069] 21 parts by weight of ABS were dried at 90°C for 24 hours, and then mixed evenly with 63 parts by weight of modified polycarbonate, 5 parts by weight of modified carbon fiber, 0.3 parts by weight of antioxidant, and 1 part by weight of acidic lubricant. The mixture was then fed into an extruder for extrusion granulation. The extrusion temperatures from zone 1 to zone 10 were 80, 120, 230, 240, 240, 240, 240, 240, 240, 240, and 240°C, respectively. The main machine speed was 550 r / min. The resulting particles were then dried overnight at 100°C to obtain a weather-resistant ABS alloy. The remaining steps and components were the same as in Example 2.

[0070] Example of effect

[0071] Impact performance: According to GB / T1043.1 standard, the impact performance of weather-resistant ABS alloys prepared in the examples and comparative examples was tested at room temperature and -40℃ using an impact testing machine. The load was set at 5.5J, the specimen size was 80*10*4mm, the notch depth was 2mm, and 5 specimens were tested. The final data was the average value. For low-temperature testing, the impact specimens were placed in a medical low-temperature freezer and frozen at the set temperature for 24 hours. They were then quickly taken out for testing. The testing process for each specimen was completed within 10 seconds.

[0072] Flame retardancy: The flame retardancy of the weather-resistant ABS alloys prepared in the examples and comparative examples was tested according to the American ANSI / UL-94-1985 standard; the limiting oxygen index test is the minimum oxygen concentration required for the weather-resistant ABS alloys prepared in the examples and comparative examples to maintain flaming combustion in a mixture of N2 and O2 gas; the test was conducted according to the ISO 4589-1996 standard, and the sample size was 120mm×10mm×4mm.

[0073] Tensile properties: In accordance with GB / T1040.2 standard, the weather-resistant ABS alloys prepared in the examples and comparative examples were subjected to tensile tests using a universal testing machine; the specimens were dumbbell-shaped, with a total length of 170 mm and a thickness of 4 mm; the tensile rate was 50 mm / min, the tensile load was 1000 N, 5 specimens were tested, and the final data were taken as the average value.

[0074] Weather resistance: Tested according to standard GB / T16422.2; Black label temperature: 65℃, relative humidity 65%, irradiance (340nm): 0.50w / m 2 •nm, Cycle period: continuous illumination, 102min without spraying, 18min with spraying, test time 200h.

[0075] Table 1 shows the test results of various properties of the weather-resistant ABS alloys prepared in the examples and comparative examples.

[0076] Table 1

[0077]

[0078]

[0079] As shown in Table 1, the weather-resistant ABS alloy of the present invention has good low-temperature toughness, good mechanical properties, good flame retardancy, and good weather resistance.

[0080] Compared with Example 2, Comparative Example 1 used 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, γ-glycidyl etheroxypropylmethyldiethoxysilane, and carbon dioxide to copolymerize and obtain a polysiloxane-polycarbonate block copolymer with a dendritic structure. The modified polycarbonate formed a physical crosslink with ABS through the dendritic structure, which enhanced the toughness of the material. Moreover, when the weather-resistant ABS alloy is subjected to external force, the stress concentration effect of polysiloxane is most significant in the polysiloxane phase domain. The presence of stress concentration leads to triaxial tensile stress between the PC matrix around the polysiloxane phase domain. The force leads to debonding at the interface between the polysiloxane phase domain and the surrounding PC matrix, resulting in a large number of pores. The appearance of a large number of pores can not only limit the formation and propagation of cracks in the PC matrix, but also weaken the constraint force on the deformation of the PC matrix under low temperature conditions, making it easier for the PC matrix to undergo forced high elastic deformation, thereby absorbing a large amount of impact energy and improving low temperature toughness. Furthermore, the subsequent modified polycarbonate reacts with the uncondensed Ti-OH groups on the modified carbon nanotubes to generate polytitanium siloxane, which strengthens the bond between the modified carbon nanotubes and the modified polycarbonate. The weather-resistant ABS alloy of Example 2 has good low temperature toughness, good mechanical properties, and good flame retardancy.

[0081] Compared with Example 2, Comparative Example 2 used carbon nanotubes. There are compatibility issues between ABS, modified polycarbonate and carbon nanotubes. The weather-resistant ABS alloy of Example 2 has better low-temperature toughness, better mechanical properties, better flame retardancy and better weather resistance.

[0082] Compared with Example 2, the modified polycarbonate of Comparative Example 3 was obtained by mixing PC and polysiloxane only. The compatibility between PC and polysiloxane was poor, and the compatibility between PC, polysiloxane and ABS was also poor. The weather-resistant ABS alloy of Example 2 had better low-temperature toughness, better mechanical properties, better flame retardancy and better weather resistance.

[0083] Compared with Example 2, Comparative Example 4 was obtained by copolymerizing 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, γ-glycidyl etheroxypropylmethyldiethoxysilane and carbon dioxide. The polysiloxane-polycarbonate block copolymer that could not form a dendritic structure had reduced crosslinking degree and compatibility of the weather-resistant ABS alloy. The weather-resistant ABS alloy of Example 2 had better low-temperature toughness and better mechanical properties.

[0084] Compared with Example 2, Comparative Example 5 modified polycarbonate was obtained by copolymerization of 2-(3,4-epoxycyclohexane)ethyltrimethoxysilane, octaepoxycyclohexylethyl cage polysilsesquioxane, γ-glycidyl etheroxypropyltriethoxysilane and carbon dioxide. The crosslinking density in the weather-resistant ABS alloy was too high. The weather-resistant ABS alloy of Example 2 had better low-temperature toughness and better mechanical properties.

[0085] Compared with Example 2, Comparative Example 7 directly mixed and granulated the raw material components without premixing and physical cross-linking. Polytitanium siloxane was not formed during the mixing process. The weather-resistant ABS alloy of Example 2 had better low-temperature toughness and better mechanical properties.

[0086] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A weather-resistant ABS alloy, characterized in that, By weight, the raw material components include: 20-22 parts by weight of ABS, 60-66 parts by weight of modified polycarbonate, 4-6 parts by weight of modified carbon nanotubes, 0.2-0.4 parts by weight of antioxidant, and 0.5-1.5 parts by weight of acidic lubricant; The modified polycarbonate is obtained by copolymerization of epoxy monomers and carbon dioxide; The epoxy monomer is a composition of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane. The modified carbon nanotubes are obtained by modifying carbon nanotubes with a titanate coupling agent. The weather-resistant ABS alloy is prepared by first premixing modified polycarbonate and modified carbon nanotubes, and then adding ABS, antioxidants and acidic lubricants for mixing, extrusion and granulation. The titanate coupling agent is a combination of isopropyl dioleate oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate.

2. A method for preparing a weather-resistant ABS alloy, characterized in that, The preparation steps include the following: (1) Weigh and prepare materials according to the weight proportions and raw material components as described in claim 1; (2) Mix 60-66 parts by mass of modified polycarbonate and 60-66 parts by mass of benzene in a reaction vessel, stir at high speed, and then add a benzene suspension of modified carbon nanotubes dropwise. The benzene suspension of modified carbon nanotubes contains 4-6 parts by mass of modified carbon nanotubes and 60-66 parts by mass of benzene. After the addition is complete, continue stirring for 2.8-3.2 hours. The entire addition and reaction process should be carried out under reduced pressure distillation, followed by rotary evaporation and drying to obtain the initial mixture. (3) Dry 20-22 parts by weight of ABS for 24 hours, then mix it evenly with the initial mixture, 0.2-0.4 parts by weight of antioxidant and 0.5-1.5 parts by weight of acidic lubricant, and add it to the extruder for extrusion granulation. Then dry the obtained particles overnight to obtain weather-resistant ABS alloy.

3. The method for preparing weather-resistant ABS alloy according to claim 2, characterized in that, The preparation steps of the modified polycarbonate are as follows: epoxy monomer, catalyst SalenCoCl and co-catalyst PPNCl are added to a pre-dried high-pressure reactor, and CO2 at 3-4 MPa is introduced at 25°C. The reactor is stirred at 150-250 rpm for 24 hours at 25°C to obtain the modified polycarbonate. The epoxy monomer is 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, or γ-glycidyl etheroxypropylmethyldiethoxysilane.

4. The method for preparing weather-resistant ABS alloy according to claim 3, characterized in that, The mass ratio of 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, octaepoxycyclohexylethyl cage-like polysilsesquioxane, and γ-glycidyl etheroxypropylmethyldiethoxysilane is 10:4-6:84-86; the mass ratio of epoxy monomer to catalyst SalenCoCl and co-catalyst PPNCl is 990-1010:1:

1.

5. The method for preparing weather-resistant ABS alloy according to claim 2, characterized in that, The preparation steps of the modified carbon nanotubes are as follows: 49-51 parts by mass of ferrous sulfate heptahydrate are dissolved in 200 parts by mass of distilled water, followed by 5 parts by mass of multi-walled carbon nanotubes. The mixture is ultrasonically vibrated for 25-35 minutes, then 148-152 parts by mass of hydrogen peroxide are added, and the mixture is stirred for 11.5-12.5 hours. The mixture is then filtered under reduced pressure and washed repeatedly with distilled water until the filtrate is neutral. The filtrate is then dried in a 70°C drying oven for 24 hours to obtain hydroxylated carbon nanotubes. 3 parts by mass of hydroxylated carbon nanotubes, 160 parts by mass of ethanol, and 19-21 parts by mass of titanate coupling agent are mixed and placed in an ultrasonic cleaner for ultrasonic vibration for 25-35 minutes. After ultrasonication, the mixture is reacted at 74-76°C with stirring for 3-5 hours. After the reaction, the mixture is naturally cooled to room temperature, then filtered under reduced pressure and washed repeatedly with anhydrous ethanol to remove unreacted titanate coupling agent from the reaction solution. The mixture is then dried in a 70°C drying oven for 12 hours to obtain modified carbon nanotubes.

6. The method for preparing weather-resistant ABS alloy according to claim 2, characterized in that, The titanate coupling agent includes isopropyl dioleate oxy (dioctyl phosphoyl oxy titanate), isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate; the mass ratio of isopropyl dioleate oxy (dioctyl phosphoyl oxy) titanate, isopropyl tris (dioctyl pyrophosphoyl oxy) titanate, and tetrabutyl titanate is 1:1:1.5 to 2.5.

Images