Low-density low-warpage PC / ABS alloy material for electronic appliances and preparation method thereof

Abstract

The invention provides a low-density low-warpage PC / ABS alloy material for electronic appliances and a preparation method thereof, and relates to the technical field of high polymer materials. The alloy material comprises the following components in parts by weight: 35-55 parts of PC resin, 25-40 parts of ABS resin, 3-10 parts of high rubber powder, 2-6 parts of a compatilizer, 3-8 parts of a flexibilizer, 1-3 parts of an end-capping stabilizer, 3-8 parts of a heat-resistant agent, 0.2-0.8 part of a lubricant, 0.2-0.5 part of an antioxidant, 0.15-0.5 part of a light stabilizer, 2-12 parts of modified thin-wall hollow glass beads and 3-8 parts of a modified special whisker reinforcing filler. The PC resin, the ABS resin, the high rubber powder and other auxiliaries and fillers in a proper proportion are adopted, so that the PC / ABS composite material has the characteristics of relatively low density, high heat resistance and low warpage, and also has certain mechanical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a low-density and low-warpage PC / ABS alloy material for electronic appliances and a preparation method thereof. Background Art

[0002] PC / ABS alloy material is a thermoplastic plastic made by blending PC (polycarbonate) and ABS (acrylonitrile-butadiene-styrene copolymer) with a compatibilizer. It combines the excellent properties of both materials: the excellent formability of ABS with the mechanical properties, impact strength, heat resistance, and UV resistance of PC. It can be widely used in automotive interior parts, electronic equipment, communications equipment, household appliances, and lighting equipment.

[0003] The ratio of PC to ABS will affect the various properties of PC / ABS materials, such as strength, toughness, thermal stability, density, etc. The density of PC is 1.18-1.22g / cm 3 , the density of ABS is 1.04-1.06g / cm 3 Although a high proportion of PC content improves performance, it also increases the specific gravity of PC / ABS alloy materials. Generally, the density of PC / ABS alloy is 1.13-1.17g / cm 3 , and the density of some glass fiber reinforced and talc filled PC / ABS alloy materials has reached 1.3g / cm 3 Patent document CN107353569A provides a low-density, high-heat-resistant PC / ABS alloy material, but it only reduces the PC content to achieve the purpose of reducing the material density. The increase in ABS inevitably leads to a decrease in material strength, and its maximum flexural modulus is only 2200 MPa. Patent document CN107936521A uses chemical foaming agent technology to obtain lightweight PC / ABS material, but this technology can only be added during injection molding and cannot be used to produce alloy particles that are universal for injection molding machines.

[0004] With the increasing demand for lightweight and thinner items, ordinary PC / ABS alloy materials have become difficult to meet, and people have turned to lighter polyolefin modified materials as a substitute. However, the strength and heat resistance of modified materials such as PP and PE are far behind those of engineering plastics. In addition, with the trend of high-strength and thin-walled injection molded parts, the use of glass fiber reinforced materials in PC / ABS alloys will cause the disadvantage of warping. Based on this, the present invention provides a PC / ABS alloy material with relatively low density, high heat resistance, low warping, and mechanical properties suitable for use as electronic and electrical injection molded parts, so as to achieve the purpose of weight reduction and thinning, and the production process is simple and suitable for continuous industrial production. Summary of the Invention

[0005] One of the purposes of the present invention is to provide a low-density and low-warpage PC / ABS alloy material for electronic appliances to solve the problem of poor performance of PC / ABS alloy materials;

[0006] A second object of the present invention is to provide a method for preparing a low-density, low-warpage PC / ABS alloy material for electronic appliances, which has a simple production process and is suitable for continuous production.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] In a first aspect, a low-density, low-warpage PC / ABS alloy material for electronic appliances comprises the following components in parts by weight:

[0009] 35-55 parts of PC resin, 25-40 parts of ABS resin, 3-10 parts of high-rubber powder, 2-6 parts of compatibilizer, 3-8 parts of toughening agent, 1-3 parts of end-capping stabilizer, 3-8 parts of heat-resistant agent, 0.2-0.8 parts of lubricant, 0.2-0.5 parts of antioxidant, 0.15-0.5 parts of light stabilizer, 2-12 parts of modified thin-walled hollow glass microspheres, 3-8 parts of modified special whisker reinforcing filler.

[0010] Furthermore, the melt flow rate of the PC resin is 8-12 g / 10 min (300° C., 1.2 kg), and a medium-viscosity PC resin brand is selected.

[0011] Furthermore, in the ABS resin, the AN (acrylonitrile) content is ≥25%.

[0012] Furthermore, the rubber content of the high-rubber powder is 65-75%. Preferably, the high-rubber powder is Sabic high-rubber powder with the brand name Blendex338.

[0013] Furthermore, the compatibilizer is linear low-density polyethylene grafted with maleic anhydride, and the maleic anhydride grafting rate is 0.5%-1.2%.

[0014] Furthermore, the toughening agent is a terpolymer of styrene / acrylonitrile / glycidyl methacrylate; preferably, the toughening agent is Jiayirong SBG001.

[0015] Furthermore, the end-capping stabilizer is ethylene / acrylate / glycidyl methacrylate copolymer; preferably, the end-capping stabilizer is Arkema AX8900.

[0016] Furthermore, the heat-resistant agent is a styrene / N-phenylmaleimide / maleic anhydride copolymer; preferably, the heat-resistant agent is DENKAIPMS-NB produced by Japan Electric Chemical.

[0017] Furthermore, the lubricant is pentaerythritol stearate (PETS).

[0018] Furthermore, the antioxidant is a mixture of a hindered phenol antioxidant and a phosphite antioxidant in a mass ratio of 1:1; furthermore, the hindered phenol antioxidant is antioxidant 1076, and the phosphite antioxidant is antioxidant 168.

[0019] Furthermore, the light stabilizer is one or a combination of benzophenone, benzotriazole, triazine, polyacrylonitrile, oxamide and hindered amine.

[0020] Furthermore, the preparation method of the modified thin-walled hollow glass microspheres comprises the following steps:

[0021] The thin-walled hollow glass microspheres are placed under stirring and heating at 110-130° C. for 15-30 minutes, a silane coupling agent diluent is sprayed and added, and the mixture is stirred at a constant temperature for 15-20 minutes; the polyester wax is then added and mixed for 10-15 minutes to obtain modified thin-walled hollow glass microspheres.

[0022] Furthermore, the usage ratio of the thin-walled hollow glass microspheres to the silane coupling agent is 20-40:1; and the usage ratio of the thin-walled hollow glass microspheres to the polyester wax is 12-25:1.

[0023] Furthermore, the compressive strength of the thin-walled hollow glass microspheres is greater than 18,000 psi, and the true density is 0.6 ± 0.3 g / cm 3 As a preferred option, the thin-walled hollow glass microspheres are S60HS from 3M Company.

[0024] Furthermore, the preparation method of the modified special whisker reinforced filler comprises the following steps:

[0025] The special whisker reinforcement filler is placed at 110-130° C. and stirred and heated for 15-30 minutes, a silane coupling agent diluent is sprayed and added, and the mixture is stirred at a constant temperature for 15-20 minutes; polyester wax is then added and mixed for 10-15 minutes to obtain a modified special whisker reinforcement filler.

[0026] Furthermore, the special whisker reinforcing filler is a ceramic single crystal short fiber, specifically a single crystal short fiber grown from ceramic materials such as C, Si, Mg, Al, with a diameter of 1-3 μm and a length of 20-200 μm. Preferably, the special whisker reinforcing filler is GR-168 from Shanghai Green Asia Company.

[0027] Furthermore, the usage ratio of the special whisker reinforcement filler to the coupling agent is 15-25:1; the usage ratio of the special whisker reinforcement filler to the polyester wax is 10-20:1.

[0028] Furthermore, the silane coupling agent dilution solution is composed of a mixture of a silane coupling agent and anhydrous ethanol in a volume ratio of 1:5, and the silane coupling agent is an amino-containing silane, preferably KH-550.

[0029] Furthermore, the temperature range of the polyester wax is 180-200°C; preferably, the polyester wax is made from German 691.

[0030] In a second aspect, a method for preparing a low-density, low-warpage PC / ABS alloy material for electronic appliances comprises the following steps:

[0031] Step 1: Dry the PC resin and ABS resin until the moisture content is less than 0.02%, then add high-rubber powder, compatibilizer, toughening agent, end-capping stabilizer, heat-resistant agent, lubricant, antioxidant and light stabilizer, and stir and mix to obtain a mixture;

[0032] Step 2: Add the mixed material through the main feed port of the twin-screw extruder, add the modified special whisker reinforcement filler through the first side feed, and add the modified thin-walled hollow glass microspheres through the second side feed. After extrusion and dehumidification and drying, a low-density and low-warpage PC / ABS alloy material for electronic appliances is obtained.

[0033] Furthermore, the aspect ratio of the twin-screw extruder is 40:1 or 44:1, and the extrusion temperature zones are 210-220°C, 220-230°C, 230-240°C, 235-245°C, 240-250°C, 240-250°C, 240-250°C, 240-250°C, 240-250°C, and 250-255°C, respectively.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The material utilizes appropriate proportions of PC resin and ABS resin, high-rubber powder, and other additives and fillers. The material exhibits relatively low density, high heat resistance, low warpage, and possesses certain mechanical properties. The formulation utilizes low- and medium-viscosity PC grades, along with high-melt index, high-AN content ABS grades, where the AN content is ≥25%. The high-rubber powder is selected with a rubber content of approximately 70%. The combination of low- and medium-viscosity PC grades ensures a balance between the material's fluidity and mechanical properties, while the high-melt index ABS further enhances processing fluidity. The high-rubber powder with a high rubber content provides sufficient toughness. The appropriate proportions of the three base materials produce superior basic performance. Furthermore, thin-walled hollow glass microspheres and special whisker-reinforced fillers are surface-modified and synergistically combined to further enhance the alloy's strength while maintaining its density, while also achieving a synergistic low-warpage effect.

[0036] 2. In the present invention, the thin-walled hollow glass microspheres are made of water-resistant and chemically stable borosilicate glass. The high compressive strength type is selected to reduce the breakage caused by screw processing. Its bulk density is 0.3g / cm 3 , the actual density is only 0.6g / cm 3 About 100 μm, properly added to the resin material, it can effectively reduce the overall density. In addition, the moderate particle size and its own isotropy can reduce the warping of the plastic and maintain good dimensional stability. However, the addition of hollow glass microspheres will lead to a decrease in the toughness of the material and an increase in notch sensitivity. On the other hand, the use of special whisker reinforced fillers can synergistically assist in improving the performance of the material. Special whisker reinforced fillers are single crystal short fibers grown under specific conditions from ceramic materials such as carbon, silicon, aluminum, and magnesium. They have a diameter of 1-3 μm and a length of 20-200 μm. It does not contain defects (grain boundaries, dislocations, holes, etc.) that exist in ordinary materials, and its atomic arrangement is highly ordered, so its strength is close to the theoretical value of a complete crystal. Its mechanical strength is equal to the force between adjacent atoms. The highly oriented structure of the special whisker reinforced filler (ceramic whisker) gives it the characteristics of high strength, high modulus and high elongation, and its density is only 1-1.1 g / cm 3In resin production, it can enhance various aspects of the performance of related products, including improving fineness, acid and alkali resistance, dimensional stability, surface finish, and heat resistance of products, reducing equipment wear, enhancing toughness and strength, improving mold fill, improving dielectric properties, increasing melt index, and preventing warping. An amino-containing silane coupling agent is used for pre-treatment modification of thin-walled hollow glass microspheres and specialty whisker reinforcing fillers. During the heating process, one end of the silane coupling agent forms a Si-O bond with the hydroxyl groups on the surfaces of both materials, while the amino group at the other end reacts with the carboxyl groups formed at the end of the PC chain to form a stable terminal amino bond. Furthermore, coating with a high-temperature-resistant polyester wax prevents filler agglomeration, allowing for a more even dispersion in the resin during screw processing, thus exerting its excellent performance.

[0037] 3. The present invention also provides a method for preparing a low-density, low-warpage PC / ABS alloy material for electronic appliances. By feeding modified thin-walled hollow glass microspheres and modified special whisker reinforcing fillers separately from the extruder side, the dispersion of the material in the base resin is improved, and the preparation efficiency is significantly improved. DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0039] The terms used in the examples of this application are for the purpose of describing specific implementation rules only and are not intended to limit this application. The singular forms "a", "an", "the" and "the" used in the implementation rules of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0040] It should be understood that in the various embodiments of the present application, the size of the serial number of each process does not mean the order of execution. Some or all steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation regulations of this application.

[0041] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass described in the examples of this application may be a mass unit known in the chemical industry, such as μg, mg, g, kg, etc.

[0042] Unless otherwise defined, all technical terms used hereinafter have the same meanings as those generally understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0043] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0044] The types and manufacturers of the raw materials in the following preparation examples, embodiments, comparative preparation examples and comparative examples are summarized in Table 1.

[0045] Table 1

[0046]

[0047]

[0048] The following is further described with reference to specific embodiments.

[0049] Preparation Example 1-1

[0050] This preparation example provides a method for preparing modified thin-walled hollow glass microspheres, comprising the following steps:

[0051] 1.0 kg of KH-550 and 5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 30 kg of thin-walled hollow glass microspheres were heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at constant temperature for 20 minutes; 1.5 kg of polyester wax was then added and mixed for 15 minutes to obtain modified thin-walled hollow glass microspheres.

[0052] Preparation Example 1-2

[0053] This preparation example provides a method for preparing modified thin-walled hollow glass microspheres, comprising the following steps:

[0054] 1.0 kg of KH-550 and 5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 20 kg of thin-walled hollow glass microspheres were heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at constant temperature for 20 minutes; 1.6 kg of polyester wax was then added and mixed for 15 minutes to obtain modified thin-walled hollow glass microspheres.

[0055] Preparation Examples 1-3

[0056] This preparation example provides a method for preparing modified thin-walled hollow glass microspheres, comprising the following steps:

[0057] 1.0 kg of KH-550 and 5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 40 kg of thin-walled hollow glass microspheres were heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at constant temperature for 20 minutes; 1.6 kg of polyester wax was then added and mixed for 15 minutes to obtain modified thin-walled hollow glass microspheres.

[0058] Preparation Example 2-1

[0059] This preparation example provides a method for preparing a modified special whisker reinforced filler, comprising the following steps:

[0060] 0.5 kg of KH-550 and 2.5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 10 kg of special whisker reinforcement filler was heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at constant temperature for 20 minutes; 0.6 kg of polyester wax was then added and mixed for 15 minutes to obtain a modified special whisker reinforcement filler.

[0061] Preparation Example 2-2

[0062] This preparation example provides a method for preparing a modified special whisker reinforced filler, comprising the following steps:

[0063] 0.6 kg of KH-550 and 3.0 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 10 kg of special whisker reinforcement filler was heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at a constant temperature for 20 minutes; 1 kg of polyester wax was then added and mixed for 15 minutes to obtain a modified special whisker reinforcement filler.

[0064] Preparation Example 2-3

[0065] This preparation example provides a method for preparing a modified special whisker reinforced filler, comprising the following steps:

[0066] 0.4 kg of KH-550 and 2.0 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 10 kg of special whisker reinforcement filler was heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at a constant temperature for 20 minutes; 0.5 kg of polyester wax was then added and mixed for 15 minutes to obtain a modified special whisker reinforcement filler.

[0067] Example 1

[0068] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances, comprising the following components in parts by weight:

[0069] 55 parts of PC resin, 40 parts of ABS resin, 8 parts of high-rubber powder, 2.5 parts of compatibilizer, 5 parts of toughening agent, 2.5 parts of end-capping stabilizer, 3 parts of heat-resistant agent, 0.4 parts of lubricant, 0.4 parts of antioxidant, 0.2 parts of light stabilizer, 12 parts of modified thin-walled hollow glass microspheres, and 3 parts of modified special whisker reinforcing filler.

[0070] The method for preparing the low-density and low-warpage PC / ABS alloy material for electronic appliances comprises the following steps:

[0071] Step 1: Dry 55kg PC resin and 40kg ABS resin to a moisture content of <0.02%, then add 8kg high-strength rubber powder, 5kg toughening agent, 2.5kg compatibilizer, 2.5kg end-capping stabilizer, 3kg heat-resistant agent, 0.4kg lubricant, 0.4kg antioxidant and 0.2kg light stabilizer, add the above materials into a high-speed mixer, stir and mix at high speed to obtain a mixture;

[0072] Step 2: Use a twin-screw extruder with double-side feeding, the aspect ratio of the twin-screw extruder is 40:1, the processing temperature is set to 180-250℃, the working extrusion temperature zones are 210-220℃, 220-230℃, 230-240℃, 235-245℃, 240-250℃, 240-250℃, 240-250℃, 240-250℃, 240-250℃, 250-255℃, and the devolatilization vacuum degree is (-0.10)-(-0.07)MPa; the mixture was added through the main feeding port of the twin-screw extruder, 3kg of the modified special whisker reinforced filler prepared by Preparation Example 2-1 was added through the first side feed, and 12kg of the modified thin-walled hollow glass microspheres prepared by Preparation Example 1-1 were added through the second side feed. The material strips coming out of the head were cooled and formed in a water tank, dehumidified in a blow dryer, and pelletized by a pelletizer to obtain a low-density and low-warpage PC / ABS alloy material for electronic appliances.

[0073] Example 2

[0074] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the modified special whisker reinforcing filler is replaced by the preparation of Preparation Example 2-2, and the modified thin-walled hollow glass microspheres are replaced by the preparation of Preparation Example 1-2.

[0075] The preparation method is the same as that in Example 1.

[0076] Example 3

[0077] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the modified special whisker reinforcing filler is replaced by the preparation of Preparation Example 2-3, and the modified thin-walled hollow glass microspheres are replaced by the preparation of Preparation Example 1-3;

[0078] The preparation method is the same as that in Example 1.

[0079] Example 4

[0080] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the amount of PC resin is replaced with 35 kg and the amount of ABS resin is replaced with 25 kg.

[0081] The preparation method is the same as that in Example 1.

[0082] Example 5

[0083] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the amount of PC resin is replaced with 40 kg and the amount of ABS resin is replaced with 32 kg.

[0084] The preparation method is the same as that in Example 1.

[0085] Example 6

[0086] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the amount of modified special whisker reinforcing filler is replaced with 8 kg, and the amount of modified thin-walled hollow glass microspheres is replaced with 2 kg.

[0087] The preparation method is the same as that in Example 1.

[0088] Example 7

[0089] This embodiment provides a low-density, low-warpage PC / ABS alloy material for electronic appliances. The difference from Example 1 is that only the amount of modified special whisker reinforcing filler is replaced with 5 kg, and the amount of modified thin-walled hollow glass microspheres is replaced with 8 kg.

[0090] The preparation method is the same as that in Example 1.

[0091] Comparative Example 1

[0092] This comparative example provides a PC / ABS alloy material, which differs from Example 1 in that only the amount of modified special whisker reinforcing filler is replaced with 10 kg and the amount of modified thin-walled hollow glass microspheres is replaced with 22 kg;

[0093] The preparation method is the same as that in Example 1.

[0094] Comparative Example 2

[0095] This comparative example provides a PC / ABS alloy material, whose formula and dosage are the same as those in Example 1, except that, during its preparation method, modified special whisker reinforcing filler and modified thin-walled hollow glass microspheres are mixed with all materials and then added from the main feed port for extrusion granulation.

[0096] Comparative Preparation Example 1-1

[0097] This comparative preparation example provides a method for preparing modified thin-walled hollow glass microspheres, comprising the following steps:

[0098] 1.0 kg of KH-550 and 5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 15 kg of thin-walled hollow glass microspheres were heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at constant temperature for 20 minutes; 1.5 kg of polyester wax was then added and mixed for 15 minutes to obtain modified thin-walled hollow glass microspheres.

[0099] Comparative Preparation Example 1-2

[0100] This comparative preparation example provides a method for preparing modified thin-walled hollow glass microspheres, comprising the following steps:

[0101] 1.0 kg of KH-550 and 5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent dilution solution; 20 kg of thin-walled hollow glass microspheres were heated at 120°C with stirring for 20 minutes, and the silane coupling agent dilution solution was sprayed into the mixture, and the mixture was stirred at a constant temperature for 20 minutes to obtain modified thin-walled hollow glass microspheres.

[0102] Comparative Preparation Example 2-1

[0103] This comparative preparation example provides a method for preparing a modified special whisker reinforced filler, comprising the following steps:

[0104] 1 kg of KH-550 was mixed evenly with 2.5 kg of anhydrous ethanol to obtain a silane coupling agent diluent; 10 kg of special whisker reinforcement filler was heated at 120°C with stirring for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at a constant temperature for 20 minutes; 1.2 kg of polyester wax was then added and mixed for 15 minutes to obtain a modified special whisker reinforcement filler.

[0105] Comparative Preparation Example 2-2

[0106] This comparative preparation example provides a method for preparing a modified special whisker reinforced filler, comprising the following steps:

[0107] 0.5 kg of KH-550 and 2.5 kg of anhydrous ethanol were mixed evenly to obtain a silane coupling agent diluent; 10 kg of special whisker reinforcement filler was placed at 120° C. and stirred and heated for 20 minutes, and the silane coupling agent diluent was sprayed into the mixture, and the mixture was stirred at a constant temperature for 20 minutes to obtain a modified special whisker reinforcement filler.

[0108] Comparative Example 3

[0109] This comparative example provides a PC / ABS alloy material, which differs from Example 1 in that only the modified special whisker reinforcing filler is replaced by the one prepared in Comparative Preparation Example 2-1, and the modified thin-walled hollow glass microspheres are replaced by the one prepared in Comparative Preparation Example 1-1;

[0110] The preparation method is the same as that in Example 1.

[0111] Comparative Example 4

[0112] This comparative example provides a PC / ABS alloy material, which differs from Example 1 in that only the modified special whisker reinforcing filler is replaced by the one prepared in Comparative Preparation Example 2-2, and the modified thin-walled hollow glass microspheres are replaced by the one prepared in Comparative Preparation Example 1-2;

[0113] The preparation method is the same as that in Example 1.

[0114] Comparative Example 5

[0115] This comparative example provides a PC / ABS alloy material, which differs from Example 1 in that the modified thin-walled hollow glass microspheres prepared in Preparation Example 1-1 are not added;

[0116] The preparation method is the same as that in Example 1.

[0117] Comparative Example 6

[0118] This comparative example provides a PC / ABS alloy material, which differs from Example 1 in that the modified special whisker reinforcing filler prepared in Preparation Example 2-1 is not added;

[0119] The preparation method is the same as that in Example 1.

[0120] The relevant raw materials and amounts in Examples 1-7 and Comparative Examples 1-6 are summarized in Table 2.

[0121] Table 2

[0122]

[0123]

[0124] The alloy materials prepared in Examples 1-7 and Comparative Examples 1-6 were injection molded into standard test specimens according to standard dimensions for performance testing. The test items and testing methods are as follows:

[0125] (1) Melt flow rate: refer to GB / T3682 (260℃ / 5kg);

[0126] (2) Density: refer to GB / T1033;

[0127] (3) Izod notched impact strength - IZOD: refer to GB / T1843 (23°C);

[0128] (4) Bending performance: refer to GB / T9341;

[0129] (5) Tensile properties: refer to GB / T1040;

[0130] (6) Heat deformation temperature (HDT): refer to GB / T1634 (0.45MPa);

[0131] (7) Vicat softening temperature: refer to GB / T1633 (B50);

[0132] (8) Warpage: Referring to GBT4677.5, alloy particles were molded into 10 mm × 5 mm × 1 mm specimens using an injection molding machine or a die press. The bending side length was 10 mm. Warpage (%) = warpage height (mm) / bending side length (10 mm) × 100%. Generally, the standard for electronic circuit boards is <0.75%, and the lower the better.

[0133] The test results are shown in Table 3.

[0134] Table 3

[0135]

[0136]

[0137] It can be seen from the test results of Examples 1-7 that, under appropriate proportions and ratios of modified hollow glass microspheres and modified reinforcing whisker fillers, sufficient pretreatment modification can make the fillers better dispersed in the resin, thereby reducing the density and ensuring the strength, while synergistically reducing the warpage of the material to a very low value.

[0138] Comparing Example 1 and Comparative Example 1, after increasing the proportion of the total amount of modified hollow glass microspheres and modified reinforced whisker fillers, the improvement of material toughness has little effect, and the mechanical properties (toughness) are significantly reduced, indicating that the two cannot be added in excess. Comparing Example 1 and Comparative Example 2, the addition of pre-treated modified hollow glass microspheres and reinforced whisker fillers from the front feed port of the twin-screw will cause the morphology of the filling material to be broken, greatly reducing the effect. Comparing Example 1 and Comparative Example 3, if the amount of silane coupling agent and coating dispersant added during the pretreatment modification of hollow glass microspheres and special whisker reinforced fillers is too large, it will cause filler agglomeration and material performance loss caused by small molecules. Comparing Example 1 and Comparative Example 4, high temperature resistant polyester wax is further coated on hollow glass microspheres and special whisker reinforced fillers to avoid performance loss caused by filler agglomeration. Comparing Example 1 and Comparative Examples 5-6, when hollow glass microspheres and special whisker reinforced fillers are added separately, the performance is relatively poor.

[0139] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0140] The above disclosures are only a few specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the scope of protection of the present invention.

Claims

1. A low-density, low-warpage PC / ABS alloy material for electronic appliances, characterized in that: According to parts by weight, it includes the following components: 35-55 parts of PC resin, 25-40 parts of ABS resin, 3-10 parts of high-rubber powder, 2-6 parts of compatibilizer, 3-8 parts of toughening agent, 1-3 parts of end-capping stabilizer, 3-8 parts of heat-resistant agent, 0.2-0.8 parts of lubricant, 0.2-0.5 parts of antioxidant, 0.15-0.5 parts of light stabilizer, 2-12 parts of modified thin-walled hollow glass microspheres, 3-8 parts of modified special whisker reinforcing filler.

2. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The preparation method of the modified thin-walled hollow glass microspheres comprises the following steps: The compressive strength is greater than 18000psi and the true density is 0.6±0.3g / cm 3 The thin-walled hollow glass microspheres are placed at 110-130° C. and stirred and heated for 15-30 minutes, a silane coupling agent diluent is sprayed and added, and the mixture is stirred at a constant temperature for 15-20 minutes; polyester wax is then added and mixed for 10-15 minutes to obtain modified thin-walled hollow glass microspheres.

3. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 2, characterized in that: The usage ratio of the thin-walled hollow glass microspheres to the silane coupling agent is 20-40:1; the usage ratio of the thin-walled hollow glass microspheres to the polyester wax is 12-25:

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4. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The preparation method of the modified special whisker reinforced filler comprises the following steps: A special whisker reinforcement filler with a diameter of 1-3 μm and a length of 20-200 μm is placed at 110-130° C. and stirred and heated for 15-30 minutes, a silane coupling agent diluent is sprayed and added, and the mixture is stirred at a constant temperature for 15-20 minutes; polyester wax is then added and mixed for 10-15 minutes to obtain a modified special whisker reinforcement filler.

5. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 4, characterized in that: The usage ratio of the special whisker reinforcement filler to the coupling agent is 15-25:1; the usage ratio of the special whisker reinforcement filler to the polyester wax is 10-20:

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6. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The melt flow rate of the PC resin is 8-12 g / 10 min; In the ABS resin, the AN content is ≥25%; The rubber content of the high-rubber powder is 65-75%.

7. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The compatibilizer is linear low-density polyethylene grafted with maleic anhydride, and the maleic anhydride grafting rate is 0.5%-1.2%; The antioxidant is a mixture of a hindered phenol antioxidant and a phosphite antioxidant in a mass ratio of 1:1; The light stabilizer is one or a combination of benzophenone, benzotriazole, triazine, polyacrylonitrile, oxamide and hindered amine.

8. The low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The end-capping stabilizer is ethylene / acrylate / glycidyl methacrylate copolymer; The heat-resistant agent is styrene / N-phenylmaleimide / maleic anhydride copolymer; The lubricant is pentaerythritol stearate.

9. A method for preparing a low-density, low-warpage PC / ABS alloy material for electronic appliances, for preparing the low-density, low-warpage PC / ABS alloy material for electronic appliances according to claim 1, characterized in that: The following steps are involved: Step 1: Dry the PC resin and ABS resin until the moisture content is less than 0.02%, then add high-rubber powder, compatibilizer, toughening agent, end-capping stabilizer, heat-resistant agent, lubricant, antioxidant and light stabilizer, and stir and mix to obtain a mixture; Step 2: Add the mixed material through the main feed port of the twin-screw extruder, add the modified special whisker reinforcement filler through the first side feed, and add the modified thin-walled hollow glass microspheres through the second side feed. After extrusion and dehumidification and drying, a low-density and low-warpage PC / ABS alloy material for electronic appliances is obtained.

10. The method for preparing a low-density and low-warpage PC / ABS alloy material for electronic appliances according to claim 9, characterized in that: The length-to-diameter ratio of the twin-screw extruder is 40:1 or 44:1, and the extrusion temperature zones are 210-220°C, 220-230°C, 230-240°C, 235-245°C, 240-250°C, 240-250°C, 240-250°C, 240-250°C, 240-250°C, and 250-255°C respectively.

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