Low-temperature-resistant PMMA / ASA alloy material and preparation method thereof

Abstract

The invention relates to the field of PMMA / ASA alloy materials, in particular to a low-temperature-resistant PMMA / ASA alloy material and a preparation method thereof, and the low-temperature-resistant PMMA / ASA alloy material comprises 60-75% of polymethyl methacrylate; the content of the acrylonitrile-acrylate-styrene copolymer is 20 to 30 percent; 0-3% of a compatilizer, the content of which is 0-3%; 0-5% of a low-temperature flexibilizer, the content of which is 0-5%; the content of the antioxidant is 0.1 to 1 percent; the content of the lubricating agent is 0.1 to 1 percent; and the content of the organic toner is 0.2-1%. The PMMA / ASA melt-blended material has excellent weather resistance and good surface gloss, and the special low-temperature flexibilizer is added to enhance the toughness of the material, especially the impact in a low-temperature environment, so that the requirements of the automobile air-inlet grille in a severe external environment are met.

Description

Technical Field

[0001] The invention relates to the field of PMMA / ASA alloy materials, and in particular to a low-temperature resistant PMMA / ASA alloy material and a preparation method thereof. Background Art

[0002] PMMA / ASA alloy is a composite material made of two plastics, polymethyl methacrylate (PMMA) and acrylonitrile-butadiene-styrene (ASA). This alloy combines the advantages of PMMA and ASA, and has excellent weather resistance, impact resistance and chemical corrosion resistance, as well as high transparency, high gloss and good processing performance.

[0003] Invention patent 202310137504.7 discloses a fingerprint-resistant high-gloss black PMMA / ASA composition and its preparation method, the composition includes polymethyl methacrylate, acrylonitrile-acrylate-styrene copolymer, self-cleaning modifier PA-g-MAH and other additives; wherein the mass ratio of polymethyl methacrylate, acrylonitrile-acrylate-styrene copolymer and self-cleaning modifier PA-g-MAH is (50-80): (20-40): (5-10). The preparation method comprises the following steps: polymethyl methacrylate, acrylonitrile-acrylate-styrene copolymer, self-cleaning modifier PA-g-MAH, antioxidant, lubricant and black toner are mixed by mass; the mixture is blended and granulated by a twin-screw extruder, and after melt extrusion, a fingerprint-resistant high-gloss black PMMA / ASA composition is obtained. The above patent can ensure the good compatibility of PA6 / 66-g-MAH and PMMA / ASA resin, and can achieve obvious fingerprint resistance effect.

[0004] The above scheme provides a fingerprint-resistant high-gloss black PMMA / ASA composition and a preparation method thereof. The fingerprint resistance and surface gloss of the material are studied, but the impact toughness of the material is less studied, especially the toughness of the material in a low temperature environment is not solved.

[0005] Therefore, in the existing technical solutions, PMMA / ASA alloy, as a common material for automobile air intake grilles, has excellent weather resistance and surface gloss, but its low-temperature impact resistance is low. With the diversification of automobile application scenarios, such as: high-cold areas, perennial hot areas, etc., cracking often occurs due to insufficient material toughness. Therefore, traditional PMMA / ASA alloys cannot meet product performance requirements, so it is urgent to develop a PMMA / ASA alloy material that is resistant to low-temperature impact. Summary of the invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a PMMA / ASA alloy material resistant to low-temperature impact, which greatly improves the toughness of the material at low temperatures by introducing a low-temperature toughening agent, selects organic black powder to improve the surface gloss of the material, and maintains a certain light transmittance.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is: a low-temperature resistant PMMA / ASA alloy material, including polymethyl methacrylate, the content of which is 60-75%; acrylonitrile-acrylate-styrene copolymer, the content of which is 20-30%; a compatibilizer, the content of which is 0-3%; a low-temperature toughening agent, the content of which is 0-5%; an antioxidant, the content of which is 0.1-1%; a lubricant, the content of which is 0.1-1%; and an organic colorant, the content of which is 0.2-1%.

[0008] The low temperature resistant PMMA / ASA alloy material, the polymethyl methacrylate is a high flow resin with a melt index of 8-10g / 10min, the acrylonitrile-acrylate-styrene copolymer is an acrylate core-shell copolymer, and the average rubber particle size is 200nm.

[0009] The low-temperature resistant PMMA / ASA alloy material described above, wherein the compatibilizer is methyl methacrylate glycidyl ester grafted with styrene-maleic anhydride.

[0010] The low-temperature resistant PMMA / ASA alloy material mentioned above, wherein the low-temperature toughening agent is an organic silicon toughening agent, comprises a core-shell structure composed of silicone rubber, polyacrylate and nano-silica, and when blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, forms a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silica phase.

[0011] A method for preparing a low-temperature resistant PMMA / ASA alloy material as described in any one of the above, comprising the following steps: Step 1: Preliminarily mix polymethyl methacrylate pellets, acrylonitrile-acrylate-styrene copolymer pellets, a compatibilizer, and a low-temperature toughening agent, and stir evenly; Step 2: Add the powder additives evenly according to the weight ratio into the PMMA / ASA resin mixed in step 1 and mix them evenly again; Step 3: adding the mixed material obtained in step 2 to a twin-screw extruder with an aspect ratio of 40:1 for extrusion; Step 4: The extruded material strands are cooled to room temperature in a water trough and pelletized by a pelletizer.

[0012] The preparation method of the above-mentioned low-temperature resistant PMMA / ASA alloy material, the low-temperature toughening agent is an organic silicon toughening agent, including a core-shell structure composed of silicone rubber, polyacrylate and nano-silica, and when blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silica phase is formed.

[0013] The method for preparing the above-mentioned low-temperature resistant PMMA / ASA alloy material, the temperatures of each temperature zone of the twin-screw extruder are: zone one, 180~200°C; zone two, 220~230°C; zone three, 220~230°C; zone four, 220~230°C; zone five, 220~235°C; zone six, 220~235°C; zone seven, 220~230°C; zone eight, 220~230°C; zone nine, 220~230°C; zone ten, 220~230°C; head, 225~235°C.

[0014] In the method for preparing the low-temperature resistant PMMA / ASA alloy material, two vacuum stages are installed on the fifth and seventh zones of the twin-screw extruder.

[0015] In the above-mentioned method for preparing the low-temperature resistant PMMA / ASA alloy material, the powder additives include a lubricant, a primary antioxidant, an auxiliary antioxidant, and an anti-ultraviolet agent.

[0016] The low-temperature resistant PMMA / ASA alloy material and the preparation method thereof have the following beneficial effects: the material after melt blending of PMMA / ASA has excellent weather resistance and good surface gloss, and by adding a special low-temperature toughening agent, the toughness of the material is enhanced, especially the impact resistance under low-temperature environment, so as to meet the requirements of the automobile air intake grille under harsh external environment; the low-temperature toughening agent is a silicone-acrylate-nano silicon dioxide core-shell structure, which can be evenly distributed in the aggregate when blended with resin to form a "sea-island" structure, and under the action of external force, the expansion speed of silver streaks can be hindered to play a toughening effect, and under the action of external environment such as low temperature, its molecular chain will not be broken, and the good toughness of the material can still be maintained. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic flow chart of the preparation method of the present invention. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is described below in conjunction with specific implementation methods and drawings.

[0019] Example 1 A low temperature resistant PMMA / ASA alloy material, comprising: Polymethyl methacrylate, content is 60-75%, methyl methacrylate adopts high flow resin, and the melt index is 8-10g / 10min.

[0020] Acrylonitrile-acrylate-styrene copolymer, the content is 20-30%, the acrylonitrile-acrylate-styrene copolymer is an acrylate core-shell copolymer, and the average rubber particle size is 200nm.

[0021] The compatibilizer has a content of 0-3%, and the compatibilizer is methyl methacrylate glycidyl ester grafted with styrene-maleic anhydride.

[0022] The low-temperature toughening agent has a content of 0-5%. The low-temperature toughening agent is an organic silicon toughening agent, including a core-shell structure composed of silicone rubber, polyacrylate and nano-silica. When blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silica phase is formed.

[0023] When subjected to external forces, silicone rubber can prevent the expansion of silver streaks and thus improve the toughness of the material. At the same time, because silicone rubber has good low-temperature resistance, the product can maintain good toughness even when used in low-temperature environments for a long time.

[0024] Antioxidant, content is 0.1-1%; lubricant, content is 0.1-1%; organic color powder, content is 0.2-1%.

[0025] Example 2 This embodiment provides supplementary explanation for the alloy material in Embodiment 1.

[0026] ASA (acrylonitrile, styrene, acrylic rubber ternary polymer) has excellent physical and mechanical properties. At the same time, since there is no unsaturated double bond in the molecule, its UV resistance and weather resistance are greatly improved. It has unique applications in relatively harsh external environments, such as: exterior mirrors, radiator grilles, tail baffles, lampshades, etc. The material after melt blending PMMA / ASA has excellent weather resistance and good surface gloss, and by adding special low-temperature toughening agents to enhance the toughness of the material, especially the impact in low-temperature environments, to meet the requirements of automobile air intake grilles in harsh external environments.

[0027] The technical problem to be solved in this embodiment is to improve the toughness of the material at low temperature, and to enhance the blackness and brightness of the material by adding organic color powder, so that the material has higher surface gloss and blackness.

[0028] The present embodiment uses a low-temperature toughening agent as a silicone system toughening agent, which is composed of a core-shell structure of silicone rubber, polyacrylate and nano-silica. When blended with a resin matrix, a multilayer structure of a continuous phase - silicone rubber phase - polyacrylate - nano-silica phase is formed. When subjected to external force, the silicone rubber can hinder the expansion of silver streaks to improve the toughness of the material. At the same time, since silicone rubber has good low-temperature resistance, the product can maintain good toughness even when used in a low-temperature environment for a long time.

[0029] In order to realize PMMA / ASA alloy material with low temperature resistance and high surface gloss, the main material composition of the technical solution of this embodiment is as follows: Polymethyl methacrylate 60-75; Acrylonitrile-acrylate-styrene copolymer 20-30; Compatibilizer 0-3; Low temperature toughening agent 0-5; Antioxidant 0.1-1; Lubricant 0.1-1; Organic color powder 0.2-1.

[0030] PMMA resin acts as a matrix to provide basic performance and surface gloss for the material. ASA resin has better weather resistance, economy, and good toughness. Its addition can enable the material to maintain its surface gloss while improving its weather resistance.

[0031] In the above-mentioned formula, PMMA resin is a high-flow resin with a melting index of about 8-10g / 10min (230℃ / 3.8Kg), ASA resin is an acrylic core-shell copolymer, and the average rubber particle size is 200nm. Organic color powder is a dye that can enhance the coloring ability of the resin matrix and greatly improve the blackness of the material.

[0032] The compatibilizer is methyl methacrylate glycidyl ester grafted with styrene-maleic anhydride, which can greatly improve the compatibility between PMMA and ASA.

[0033] The low-temperature toughening agent is a silicone-acrylate-nano-silica core-shell structure. When mixed with the resin, it can be evenly distributed in the mass to form an "island-in-the-sea" structure. Under the action of external force, it will hinder the expansion speed of silver streaks and play a toughening effect. Under the influence of external environments such as low temperature, its molecular chain will not break and the material can still maintain good toughness.

[0034] Examples and comparisons of different contents of each component are shown in Table 1.

[0035] Table 1: Example of different contents of each component .

[0036] The performance tests were performed on the examples and comparative examples with different contents of each component in Table 1, and the test results are shown in Table 2.

[0037] Table 2: Performance test table of different contents of each component .

[0038] Among them, the density test standard is GB / T1033; the notched impact strength test standard is GB / T1843; the gloss test standard is ASTM D523; and the blackness test standard is GB / T7921.

[0039] This technical solution maintains the toughness of the material at low temperatures while greatly improving the impact performance of the material by reasonably matching the ratio of the compatibilizer and the low-temperature toughening agent. The acrylate in the low-temperature toughening agent has good compatibility with the resin matrix, and the silicone rubber greatly improves the toughness of the material. At the same time, in a low-temperature environment, due to the low glass transition temperature of silicone rubber, its molecular chain can still keep moving at -30°C, so it still has the effect of improving the toughness of the material. In addition, compared with ordinary pigments, organic color powder has higher dyeing ability and blackness. When applied to resin, it can make the surface of the material have the characteristics of high gloss black.

[0040] This technical solution is a technical solution of intellectual property nature generated on the basis of realizing industrialized production. The material usage is ordinary and harmless, has universal applicability, and meets environmental protection requirements. It prepares PMMA / ASA alloy materials with low temperature resistance and high surface gloss.

[0041] Example 3 A method for preparing a low-temperature resistant PMMA / ASA alloy material comprises the following steps: Step 1: Preliminarily mix polymethyl methacrylate pellets, acrylonitrile-acrylate-styrene copolymer pellets, a compatibilizer and a low-temperature toughening agent, and stir evenly.

[0042] Step 2: Add the powder additives evenly according to the weight ratio into the PMMA / ASA resin mixed in step 1 and mix them evenly again.

[0043] Step 3: Add the mixed material obtained in step 2 to a twin-screw extruder with an aspect ratio of 40:1 for extrusion.

[0044] Step 4: The extruded material strands are cooled to room temperature in a water trough and pelletized by a pelletizer.

[0045] The low temperature toughening agent is an organic silicon toughening agent, including a core-shell structure composed of silicone rubber, polyacrylate and nano-silica. When blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silica phase is formed.

[0046] The temperatures of each temperature zone of the twin-screw extruder are: zone 1, 180~200℃; zone 2, 220~230℃; zone 3, 220~230℃; zone 4, 220~230℃; zone 5, 220~235℃; zone 6, 220~235℃; zone 7, 220~230℃; zone 8, 220~230℃; zone 9, 220~230℃; zone 10, 220~230℃; die head, 225~235℃.

[0047] Two sections of vacuum are installed on the fifth and seventh zones of the twin-screw extruder.

[0048] Powder additives include lubricants, primary antioxidants, auxiliary antioxidants, and anti-ultraviolet agents.

[0049] Specifically, PMMA and ASA pellets are preliminarily mixed with compatibilizers and toughening agents, and powder additives (lubricants, primary antioxidants, auxiliary antioxidants, and anti-ultraviolet agents) are evenly added to the mixed PMMA / ASA resin according to the weight ratio and mixed again. After mixing evenly, they are added to a twin-screw extruder (equipment length-diameter ratio 40:1) for extrusion. The temperatures of each temperature zone of the extruder are: zone 1, 180~200℃; zone 2, 220~230℃; zone 3, 220~230℃; zone 4, 220~230℃; zone 5, 220~235℃; zone 6, 220~235℃; zone 7, 220~230℃; zone 8, 220~230℃; zone 9, 220~230℃; zone 10, 220~230℃; die head, 225~235℃. The extruded material is cooled to room temperature in a water tank and pelletized by a pelletizer. The length-to-diameter ratio of the twin-screw extruder is 40:1, and two vacuum stages are installed on the 5th and 7th stages of the equipment to achieve double vacuum control, thereby improving and controlling the odor of the modified product.

[0050] The above embodiments are only for illustrating the inventive concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made based on the essence of the content of the present invention should be included in the protection scope of the present invention.

Claims

1. A low temperature resistant PMMA / ASA alloy material, characterized by: It includes polymethyl methacrylate, with a content of 60-75%; acrylonitrile-acrylate-styrene copolymer, with a content of 20-30%; a compatibilizer, with a content of 0-3%; a low-temperature toughening agent, with a content of 0-5%; an antioxidant, with a content of 0.1-1%; a lubricant, with a content of 0.1-1%; and an organic color powder, with a content of 0.2-1%.

2. The low temperature resistant PMMA / ASA alloy material according to claim 1, characterized in that: The polymethyl methacrylate has a melt index of 8-10 g / 10 min, the acrylonitrile-acrylate-styrene copolymer is an acrylate core-shell copolymer, and the average particle size of the rubber is 200 nm.

3. The low temperature resistant PMMA / ASA alloy material according to claim 1, characterized in that: The compatibilizer is methyl methacrylate glycidyl ester grafted with styrene-maleic anhydride.

4. The low temperature resistant PMMA / ASA alloy material according to claim 1, characterized in that: The low-temperature toughening agent is an organic silicon toughening agent, which includes a core-shell structure composed of silicone rubber, polyacrylate and nano-silicon dioxide. When blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silicon dioxide phase is formed.

5. A method for preparing a low temperature resistant PMMA / ASA alloy material according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Preliminarily mix polymethyl methacrylate pellets, acrylonitrile-acrylate-styrene copolymer pellets, a compatibilizer, and a low-temperature toughening agent, and stir evenly; Step 2: Add the powder additives evenly according to the weight ratio into the PMMA / ASA resin mixed in step 1 and mix them evenly again; Step 3: adding the mixed material obtained in step 2 to a twin-screw extruder with an aspect ratio of 40:1 for extrusion; Step 4: The extruded material strands are cooled to room temperature in a water trough and pelletized by a pelletizer.

6. The method for preparing the low temperature resistant PMMA / ASA alloy material according to claim 5, characterized in that: The low-temperature toughening agent is an organic silicon toughening agent, which comprises a core-shell structure composed of silicone rubber, polyacrylate and nano-silicon dioxide. When blended with methyl methacrylate and acrylonitrile-acrylate-styrene copolymer, a continuous phase of a multilayer structure including an organic silicon rubber phase-polyacrylate-nano-silicon dioxide phase is formed.

7. The method for preparing the low temperature resistant PMMA / ASA alloy material according to claim 5, characterized in that: The temperatures of each temperature zone of the twin-screw extruder are: zone one, 180-200°C; zone two, 220-230°C; zone three, 220-230°C; zone four, 220-230°C; zone five, 220-235°C; zone six, 220-235°C; zone seven, 220-230°C; zone eight, 220-230°C; zone nine, 220-230°C; zone ten, 220-230°C; and die head, 225-235°C.

8. The method for preparing the low temperature resistant PMMA / ASA alloy material according to claim 6, characterized in that: Two stages of vacuum are installed on the fifth and seventh zones of the twin-screw extruder.

9. The method for preparing the low temperature resistant PMMA / ASA alloy material according to claim 6, characterized in that: The powder additives include lubricants, primary antioxidants, auxiliary antioxidants, and anti-ultraviolet agents.

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