Preparation and application of high-glossiness PMMA / PC / ASA composite material

Abstract

The invention belongs to a material modification technology, relates to high-surface-quality plastic, and particularly relates to preparation and application of a high-glossiness PMMA / PC / ASA composite material, in particular to application of the high-glossiness PMMA / PC / ASA composite material to an automobile exterior trimming panel. The high-glossiness PMMA / PC / ASA composite material is prepared by taking polymethyl methacrylate resin, polycarbonate, a toughening agent, a compatilizer, a coloring agent and an auxiliary agent as raw materials. The invention mainly solves the problem that the surface appearance and performance are difficult to balance when the PMMA / ASA alloy material is compounded with the PC material, thereby obtaining the PMMA / PC / ASA alloy material with high glossiness, high heat resistance and high weather resistance.

Description

Technical Field

[0001] The invention belongs to material modification technology and relates to a high-surface-quality plastic, specifically to the preparation and application of a high-gloss PMMA / PC / ASA composite material, especially to the application in automobile exterior panels. Background Art

[0002] Polymethyl methacrylate, commonly known as acrylic, is a material with high hardness and high light transmittance, and is often used as a substitute for glass. Polycarbonate, also known as PC, is a high molecular polymer containing carbonate groups in the molecular chain. According to the structure of the ester group, it can be divided into aliphatic, aromatic, aliphatic-aromatic and other types. PMMA and ASA have similar solubility parameters, which allows them to obtain excellent performance combined with each other without affecting the appearance after physical blending, but the heat resistance of both is poor, which limits the use of PMMA+ASA alloy high-gloss paint-free materials. In order to obtain better heat resistance, technicians choose to add PC materials with high glass transition temperature and high Vicat softening point temperature for blending, but it will affect the appearance of PMMA / ASA alloy products and produce birefringence, making it difficult to promote and apply them in large quantities on automotive exterior parts.

[0003] Therefore, it is necessary to develop a new formula to prepare high-gloss PMMA / PC / ASA materials so that they can meet the use of high-gloss paint-free materials on the basis of heat resistance. Summary of the invention

[0004] Faced with the production side's requirement that the L value is less than or equal to 24, it is currently difficult to achieve PMMA / PC / ASA composite materials, especially there is no disclosure of PMMA / PC / ASA composite materials with Vicat greater than 105°C and L value ≤ 24. The present invention solves the problem of high L value while achieving the heat resistance of PMMA / PC / ASA composite materials. The key technology lies in the selection of suitable compatibilizers and PC materials combined with the formula ratio. Therefore, the present invention obtains particles that meet the production side's requirements.

[0005] The present invention adopts the following technical scheme.

[0006] A high-gloss PMMA / PC / ASA composite material, the preparation raw materials of which include polymethyl methacrylate resin, polycarbonate, a toughening agent, a compatibilizer, a colorant and an auxiliary agent.

[0007] The invention discloses a method for preparing the high-gloss PMMA / PC / ASA composite material, comprising the following steps: melt-mixing raw materials including polymethyl methacrylate resin, polycarbonate, a toughening agent, a compatibilizer, a colorant and an auxiliary agent to obtain the high-gloss PMMA / PC / ASA composite material.

[0008] In the present invention, the raw materials are melt-mixed by the prior art, such as using an extruder.

[0009] In the present invention, the raw materials for preparing the high-gloss PMMA / PC / ASA composite material are composed of polymethyl methacrylate resin, polycarbonate, a toughening agent, a compatibilizer, a colorant and an auxiliary agent.

[0010] Preferably, the mass ratio of polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent is (15-40): (40-65): (5-20): (1-10): (2-6): (0.2-1).

[0011] More preferably, the mass ratio of polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent is (20-35): (50-60): (10-15): (3-7): (3-5): (0.4-0.8).

[0012] In the present invention, the toughening agent is acrylonitrile-butyl acrylate-styrene copolymer; and the compatibilizer is styrene-methyl methacrylate-acrylonitrile terpolymer.

[0013] In the present invention, the compatibilizer is prepared by polymerization of styrene, methyl methacrylate and acrylonitrile as monomers, and conventional solution polymerization can be adopted; preferably, the solution polymerization is carried out in the presence of an initiator and a molecular weight regulator.

[0014] Preferably, by mass percentage, methyl methacrylate is 25-35%, styrene content is 15-20%, acrylonitrile content is 10-15%, initiator is 0.1-0.5%, molecular weight regulator is 0.1-0.5%, and solvent is the balance.

[0015] In the present invention, the auxiliary agent includes an antioxidant, a weathering agent, an anti-hydrolysis agent and a lubricant.

[0016] PMMA+ASA composite materials are currently widely used in the automotive field, mainly in automotive exterior parts, because they can achieve high gloss effects without spraying paint. However, with the development of the automotive field, the requirements for the heat resistance and weather resistance of materials are getting higher and higher. The present invention mainly solves the problem that it is difficult to balance the surface appearance and performance of PMMA / ASA alloy materials when they are used in combination with PC materials, thereby obtaining a PMMA / PC / ASA alloy material with high gloss, high heat resistance and high weather resistance.

[0017] The invention discloses application of the high-gloss PMMA / PC / ASA composite material in preparing a high-gloss material.

[0018] The invention discloses application of the high-gloss PMMA / PC / ASA composite material in preparing automobile materials.

[0019] The invention discloses application of the high-gloss PMMA / PC / ASA composite material in preparing high-gloss automobile materials.

[0020] The invention discloses application of the high-gloss PMMA / PC / ASA composite material in preparing a heat-resistant high-gloss material.

[0021] The invention discloses an automobile material, and the raw materials for preparing the automobile material include the high-gloss PMMA / PC / ASA composite material.

[0022] The glossiness of the PMMA / PC / ASA high-gloss paint-free material is required to be above 85, and the glossiness of existing products does not meet the requirement. The present invention can meet the requirement by adding toughening agent and compatibilizer to the main material, especially the material color blackness L value is ≤24, which meets the manufacturer's high-gloss material requirements.

[0023] After adding a compatibilizer and a toughening agent, the PMMA / PC / ASA material of the present invention has no defects such as birefringence on its surface appearance; after blending the PC material with PMMA, not only a high-gloss material is obtained, but also the advantages of high heat resistance of PC and high weather resistance of PMMA are concentrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Prepare the reactor for the compatibilizer.

[0025] Figure 2 These are photos of conventional injection molding samples of each group of particles.

[0026] Figure 3 This is a car rear wing conventionally prepared from the particles of Example 1. DETAILED DESCRIPTION

[0027] PMMA+ASA composite materials can achieve high gloss without spraying paint, but their heat resistance needs to be improved. Although polycarbonate can achieve improved thermal performance, it obviously affects the appearance of the material, and currently manufacturers have proposed a requirement of L value ≤ 24, and existing products cannot meet this requirement while meeting the heat resistance requirement. For the prepared PMMA / PC / ASA high-gloss paint-free material, the gloss requirement is above 78, and the gloss of existing products does not meet the requirement. The present invention can meet the requirements after adding toughening agent and compatibilizer to the main material, especially the material color blackness L value is ≤ 24, which meets the manufacturer's requirements for high-gloss materials.

[0028] The present invention uses polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent as raw materials to prepare a high-gloss PMMA / PC / ASA composite material, and its formula composition Polymethyl methacrylate 10~40%; Polycarbonate 40~70%; Toughening agent 5~30%; Compatibilizer 2~8%; Black pigment 3~5%; Additives 0.2~0.8% The total weight of polymethyl methacrylate resin, polycarbonate, toughening agent and compatibilizer is 100%.

[0029] Preferably, Recipe composition Polymethyl methacrylate 20~35%; Polycarbonate 50~60%; Toughening agent 10~20%; Compatibilizer 3~7%; Black pigment 3~5%; Additives 0.4~0.7% The total weight of polymethyl methacrylate resin, polycarbonate, toughening agent and compatibilizer is 100%.

[0030] The material description is as follows: The melt index of polymethyl methacrylate resin at 230°C and 3.8kg is 5-20g / min; CM205 was selected for the experiment.

[0031] The polycarbonate is a silicone copolycarbonate; 9115LT was chosen for the experiments.

[0032] Conventional polycarbonate brand: Korea Lotte 1220.

[0033] The toughening agent is acrylonitrile-butyl acrylate-styrene copolymer, and the rubber phase content thereof is 60wt%; SX-006 is selected in the experiment.

[0034] The compatibilizer is a solution-processed styrene-methyl methacrylate-acrylonitrile terpolymer. The compatibilizer is prepared by polymerization of styrene, methyl methacrylate and acrylonitrile as monomers, and conventional solution polymerization can be used; preferably, the solution polymerization is carried out in the presence of an initiator and a molecular weight regulator. Figure 1 It is a synthesis device of the compatibilizer, and the synthesis method is as follows: the device is first evacuated with nitrogen, and a certain proportion of monomers, solvents and initiators are mixed with molecular weight regulators (their respective mass fractions are 30% methyl methacrylate content, 18% styrene content, 12% acrylonitrile content, 39.4% solvent xylene, 0.3% DTBP mass fraction of initiator, and 0.3% TDM mass fraction of molecular weight regulator), added into the reactor, evacuated with nitrogen for 1 hour and then started to react (reacted twice, the first reaction was at 80°C for 2 hours, and the second reaction was at 130°C for further 2 hours), and after the reaction was completed, it was dried, devolatilized and crushed to obtain the compatibilizer for standby use.

[0035] Commercially available styrene-methyl methacrylate-maleic anhydride copolymer: BP-356M.

[0036] Commercially available SMA resin: XIRAN 3500.

[0037] Commercially available transparent SAN resin: NF2200.

[0038] The additives are 1010, 168, TINUVIN 770, TINUVIN P, diphenyl carbonate anti-hydrolysis agent, and lubricant EBS, each at 0.1%.

[0039] The colorant is carrier-free carbon black (carbon black masterbatch), and the carbon black concentration is 30%-60%; 9095 from Ningbo Masterbatch Company was selected for the experiment.

[0040] The following is an explanation of the technical progress of the present invention through specific experiments. The raw materials used are existing products, and the specific preparation operations and performance tests are all conventional techniques.

[0041] The raw materials of the embodiment and comparative example are shown in Table 1, and the processing method is as follows: the raw materials are mixed and sent into an extruder for granulation to obtain a PMMA / PC / ASA composite material with high gloss. Specifically: The weighed raw materials are put into a high-speed batching mixer and mixed evenly at high speed to obtain a premix; then the premix is ​​sent to a twin-screw extruder through a metering device, and the materials are melted and compounded under the conveying, shearing and mixing of the screw, and then the materials are extruded, drawn, cooled and pelletized to obtain PMMA / PC / ASA resin that is easy to process. The extrusion process is as follows: twin-screw machine temperature zone: first stage temperature 180°C, second stage temperature 200°C, third stage temperature 210°C, fourth stage temperature 230°C, fifth stage temperature 240°C, sixth stage temperature 240°C, seventh stage temperature 240°C, eighth stage temperature 240°C, ninth stage temperature 240°C, tenth stage temperature 240°C, die head temperature 240°C, and a rotation speed of 300rpm; the extruded material is cooled and granulated to obtain the corresponding product.

[0042] The particles prepared by the above method were dried in a 95°C forced air drying oven for 4 hours and injection molded into test specimens. The material testing method is the prior art and is briefly described as follows: Tensile strength: Tested according to ISO 527-2 standard, tensile speed 50mm / min, requirement ≥50MPa.

[0043] Simple supported beam notched impact strength: tested according to ISO 179 standard, impact energy is 4J, requirement is ≥8Kj / m 2 .

[0044] Vicat softening point: tested according to ISO 306 standard, test conditions are 5kg, 50℃ / h, requirement is ≥115℃.

[0045] Gloss: Tested according to ASTM D2457 standard, the test angle is 60°, and the requirement is ≥85.

[0046] Double refraction phenomenon: Visual evaluation of appearance, the phenomenon of inconsistent gloss and color in different areas of the same mold is divided into three levels according to the visual effect: severe / minor / none (severe is the case when unevenness is visible at basically any angle, slight is the case when no obvious unevenness is seen from the front and a small amount (less than 3 places) of unevenness is seen at a specific angle, and no obvious unevenness is seen when changing the angle). No double refraction phenomenon is required.

[0047] Appearance color: Under normal temperature of 23±2℃, a colorimeter is used to test the injection molded samples of the same mold, and the L value is required to be ≤24 (visually meet the appearance requirements of automotive parts for blackness and achieve a high-gloss black paint-free effect). This is a key requirement of existing manufacturers and a necessary performance for particles to be used in production.

[0048] Table 1 Raw materials for examples and comparative examples, Kg

[0049] Table 2 Material properties

[0050] Figure 2 These are photos of conventional injection molding samples of each group of particles; Figure 3 This is a car rear wing conventionally prepared from the particles of Example 1.

[0051] According to production, the glossiness of the PMMA / PC / ASA high-gloss paint-free material is required to be above 85, and the glossiness of the existing materials does not meet the requirements; the present invention can meet the requirements after adding toughening agent and compatibilizer, and the color blackness L value of the material after adding the compatibilizer is ≤24, which meets the strict requirements of high-gloss materials. Furthermore, after adding the compatibilizer, the PMMA / PC / ASA material has no defects such as birefringence on its surface appearance.

[0052] As can be seen from the above, after the PC material and PMMA are blended in the present invention, under the action of toughening agent and compatibilizer, not only a material with high gloss is obtained, but also the advantages of high heat resistance of PC and high weather resistance of PMMA are concentrated.

Claims

1. A high gloss PMMA / PC / ASA composite material, characterized in that: The preparation raw materials include polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent.

2. The high gloss PMMA / PC / ASA composite material according to claim 1, characterized in that: The mass ratio of polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent is (15-40): (40-65): (5-20): (1-10): (2-6): (0.2-1).

3. The high gloss PMMA / PC / ASA composite material according to claim 1, characterized in that: The toughening agent is acrylonitrile-butyl acrylate-styrene copolymer; and the compatibilizer is styrene-methyl methacrylate-acrylonitrile terpolymer.

4. The method for preparing the high gloss PMMA / PC / ASA composite material according to claim 1, characterized in that: The method comprises the following steps: melting and mixing raw materials including polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent to obtain the high-gloss PMMA / PC / ASA composite material.

5. The method for preparing the high gloss PMMA / PC / ASA composite material according to claim 1, characterized in that: The mass ratio of polymethyl methacrylate resin, polycarbonate, toughening agent, compatibilizer, colorant and auxiliary agent is (20-35): (50-60): (10-15): (3-7): (3-5): (0.4-0.8).

6. The method for preparing the high gloss PMMA / PC / ASA composite material according to claim 1, characterized in that: The compatibilizer is prepared by polymerizing styrene, methyl methacrylate and acrylonitrile as monomers.

7. Use of the high-gloss PMMA / PC / ASA composite material according to claim 1 in the preparation of high-gloss materials.

8. Use of the high-gloss PMMA / PC / ASA composite material according to claim 1 in the preparation of automotive materials.

9. Use of the high-gloss PMMA / PC / ASA composite material according to claim 1 in the preparation of high-gloss automotive materials; or use of the high-gloss PMMA / PC / ASA composite material in the preparation of heat-resistant high-gloss materials.

10. An automotive material, wherein the raw materials for preparing the material include the high-gloss PMMA / PC / ASA composite material according to claim 1.

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