Bending-resistant polycarbonate modified material and application thereof

Abstract

The invention belongs to the technical field of high polymer materials, and particularly relates to a bending-resistant polycarbonate modified material and application thereof.The bending-resistant polycarbonate modified material is prepared from, by weight, 80-90 parts of polycarbonate, 12-18 parts of thermoplastic elastomer, 8-10 parts of modified molecular sieve, 1-2 parts of compatilizer, 3-5 parts of ionic liquid, 1-1.5 parts of metal compound and 0.06-0.2 part of antioxidant; the preparation method of the modified molecular sieve comprises the following steps: (1) mixing a molecular sieve, ammonia water and water, filtering, and drying a solid phase to obtain a molecular sieve intermediate; and (2) calcining the molecular sieve intermediate to obtain the modified molecular sieve. The polycarbonate modified material disclosed by the invention has excellent toughness, namely bending resistance, freezing resistance and heat and humidity resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a bending-resistant polycarbonate modified material and application thereof. Background Art

[0002] Polycarbonate is a thermoplastic with excellent mechanical properties, heat resistance and transparency. It is widely used in the manufacture of various products, including eyeglass lenses, CDs, DVDs, automotive parts, medical devices, and electronic and electrical products. The high impact strength of polycarbonate makes it an ideal material for making bulletproof glass and helmets. In addition, polycarbonate has excellent mechanical properties, including high impact strength and good heat resistance, making it an ideal choice for making durable and lightweight housings. Polycarbonate housing materials also have excellent transparency and can be used in products that need to show internal structures or beautiful designs. In addition, it also has good electrical insulation properties and UV resistance, making it suitable for housings of electronic devices and outdoor equipment. The processability of polycarbonate housings is also very good, and housings with complex shapes can be easily manufactured through methods such as injection molding. Therefore, polycarbonate is widely used in housing materials, from electronic consumer products to automotive parts to industrial equipment housings.

[0003] Existing research on polycarbonate modified materials mainly focuses on improving the toughness of polycarbonate modified materials, that is, their bending resistance. For example, CN112375363B provides a method for improving the gloss of glass fiber reinforced polycarbonate by adding acrylic shell silicone rubber and polyurethane, giving the glass fiber reinforced polycarbonate a better matte effect, which can meet the gloss requirements of various processes. Among them, the glass fiber reinforced polycarbonate composition includes polycarbonate, ABS, glass fiber, acrylic shell silicone rubber, polyurethane, toughening agent, antioxidant and lubricant, etc. However, the addition of existing lubricants will cause oil precipitation of polycarbonate modified materials in a hot and humid aging environment; pure polycarbonate is prone to hydrolysis in a hot and humid environment, resulting in material destruction. In order to improve this defect, CN113072804B uses antioxidants and preservatives and antibacterial agents to protect the stability and durability of polycarbonate materials. Antioxidants can prevent the hydrolysis, mildew and powdering of polycarbonate materials. By using bentonite to absorb preservatives, antibacterial agents and cold-resistant agents, the antifreeze agent can be evenly dispersed in the polycarbonate mixture, further enhancing its stability and durability. However, the cold-resistant agent is di(2-ethylhexyl) oxalate, which will cause oil precipitation in the material in a hot and humid aging environment, and the addition of bentonite will affect the final optical properties of the material. In addition, with the increasing application of polycarbonate materials, the overall performance requirements for polycarbonate modified materials are becoming more and more stringent during application.

[0004] Therefore, there is an urgent need to provide a bending-resistant polycarbonate modified material having excellent frost resistance, moisture and heat resistance and optical properties. Summary of the invention

[0005] The object of the present invention is to provide a bending-resistant polycarbonate modified material and application thereof, wherein the bending-resistant polycarbonate modified material not only has excellent bending resistance, but also has excellent frost resistance, moisture and heat resistance and optical properties.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a bending-resistant polycarbonate modified material, wherein the raw materials of the modified material include, by weight: 80-90 parts of polycarbonate, 12-18 parts of thermoplastic elastomer, 8-10 parts of modified molecular sieve, 1-2 parts of compatibilizer, 3-5 parts of ionic liquid, 1-1.5 parts of metal compound, and 0.06-0.2 parts of antioxidant;

[0008] The preparation method of the modified molecular sieve comprises:

[0009] (1) mixing molecular sieve, ammonia water and water, filtering and solid phase drying to obtain a molecular sieve intermediate;

[0010] (2) calcining the molecular sieve intermediate to obtain a modified molecular sieve.

[0011] The polycarbonate modified material obtained by the synergistic effect of the various raw material components in the present invention not only has excellent bending resistance, but also has excellent optical properties and stability, especially moisture and heat resistance and antifreeze resistance. The addition of metal compounds in the present invention can better increase the moisture and heat resistance of the polycarbonate modified material, but the presence of metal ions will affect the color of the material, and then affect the optical properties of the final modified material. However, the inventors found that the addition of modified molecular sieves in the present invention can not only improve the defects caused by metal ions, but also synergize with metal compounds to further increase the moisture and heat resistance of the polycarbonate modified material. The inventors speculate that it may be because the modified molecular sieve obtained after alkali treatment has a more uniform and larger internal pore structure, so that the metal ions can be adsorbed inside the pores of the modified molecular sieve, avoiding the influence of metal ions on the color of the modified material. At the same time, the modified molecular sieve is still present, which can avoid the phenomenon that polycarbonate may be hydrolyzed in a humid and hot environment, so that the polymer matrix material exists stably.

[0012] Furthermore, in order to better increase the comprehensive performance of the polycarbonate modified material, the raw materials of the modified material include, by weight: 86 parts of polycarbonate, 15 parts of thermoplastic elastomer, 8.5 parts of modified molecular sieve, 1.8 parts of compatibilizer, 4.5 parts of ionic liquid, 1.3 parts of metal compound, and 0.1 part of antioxidant.

[0013] Furthermore, the molecular sieve is at least one selected from MCM-41 molecular sieve, ZSM-5 molecular sieve, MCM-22 molecular sieve, SBA-15 molecular sieve and Y-type molecular sieve, preferably ZSM-5 molecular sieve.

[0014] Furthermore, the average particle size of the molecular sieve is 0.1-2 μm, preferably 0.5-1 μm.

[0015] Furthermore, the silicon to aluminum ratio of the molecular sieve is 10-50, preferably 25.

[0016] The molecular sieve in the present invention can be obtained from the market, and preferably the ZSM-5 molecular sieve is purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., and has an average particle size of 0.75 μm and a silicon-aluminum ratio of 25.

[0017] Furthermore, in step (1), the mixing conditions include: temperature of 50-70° C., rotation speed of 1000-1500 rpm, and time of 35-50 min.

[0018] Furthermore, in step (1), the mixing conditions include: temperature of 60° C., rotation speed of 1200 rpm, and time of 45 min.

[0019] Furthermore, in step (1), the weight ratio of the molecular sieve to aqueous ammonia is 1:(5-8), preferably 1:6.

[0020] Furthermore, in step (1), the weight ratio of the molecular sieve to water is 1:(30-40), preferably 1:35.

[0021] Furthermore, in step (1), the concentration of aqueous ammonia is 13.33-14.84 mol / L.

[0022] Furthermore, in step (1), the drying conditions include: a temperature of 100-120° C. and a time of 3-7 hours.

[0023] Furthermore, in step (2), the calcination conditions include: calcination at 400-500° C. for 2-5 hours in an air atmosphere.

[0024] Furthermore, the melt flow rate of the polycarbonate at 300° C. and 1.2 kg is 10-20 g / 10 min, for example, 10 g / 10 min, 12 g / 10 min, 15 g / 10 min, 18 g / 10 min, 20 g / 10 min, preferably 12-17 g / 10 min, and more preferably 15 g / 10 min.

[0025] The polycarbonate in the present invention can be obtained from the market, and its preferred model is Shandong Luxi Chemical LXTY1615.

[0026] Furthermore, the thermoplastic elastomer is selected from at least one of POE, SEBS, SBS and TPU.

[0027] Furthermore, the thermoplastic elastomer is a combination of POE and SBS.

[0028] Furthermore, the weight ratio of POE to SBS is 1:(0.3-1), for example, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, and preferably 1:(0.4-0.5).

[0029] Furthermore, the melt flow rate of the POE at 190° C. and 2.16 kg is 0.1-1 g / 10 min, for example, 0.1 g / 10 min, 0.3 g / 10 min, 0.5 g / 10 min, 0.7 g / 10 min, 1 g / 10 min, and preferably 0.5 g / 10 min.

[0030] The POE in the present invention can be obtained from the market, and its preferred model is ENGAGE TM 8150.

[0031] Furthermore, the melt flow rate of the SBS at 190° C. and 5 kg is 1-3 g / 10 min, for example, 1 g / 10 min, 1.2 g / 10 min, 1.4 g / 10 min, 1.8 g / 10 min, 2 g / 10 min, 2.4 g / 10 min, 2.7 g / 10 min, 3 g / 10 min, and preferably 1.4 g / 10 min.

[0032] The SBS in the present invention can be obtained from the market, and its preferred model is 2100D.

[0033] In the system of the present invention, the modified molecular sieve used in the present invention has a toughening effect. As far as the polymer is concerned, the toughening effect that the modified molecular sieve can achieve is also related to the toughness of the polymer matrix itself. The inventors found that the use of thermoplastic elastomers can better increase the toughness of the polycarbonate polymer matrix, while also increasing the optical properties of the polycarbonate modified material. The reason for this may be that a specific combination of POE and SBS is selected as a thermoplastic elastomer in the present invention, wherein POE and SBS synergistically increase the toughness of the polycarbonate modified material, while the styrene segment in the SBS exhibits an optical property of negative birefringence in the composite material, and the polycarbonate exhibits an optical property of positive birefringence, which can better offset part of the birefringence, so that the polycarbonate modified material has excellent light transmittance.

[0034] The main purpose of the compatibilizer is to increase the compatibility between the various components in the system. Further, the compatibilizer is selected from at least one of styrene-maleic anhydride copolymer, POE grafted maleic anhydride and POE grafted glycidyl methacrylate.

[0035] Furthermore, the compatibilizer is a combination of styrene-maleic anhydride copolymer and POE grafted maleic anhydride.

[0036] In the present invention, styrene-maleic anhydride copolymer and POE grafted maleic anhydride are used together as compatibilizers to better increase the compatibility between the components. Furthermore, the weight ratio of the styrene-maleic anhydride copolymer to the POE grafted maleic anhydride is 1:(1.5-3), preferably 1:2.

[0037] The styrene-maleic anhydride copolymer in the present invention can be obtained commercially, for example, from Jiayirong Polymer (Shanghai) Co., Ltd., model SAM-020.

[0038] The POE grafted maleic anhydride in the present invention can be obtained commercially, for example, from Jiayirong Polymer (Shanghai) Co., Ltd., model EMI-100.

[0039] In the existing process, in order to improve the fluidity and processability of the material, a lubricant, such as pentaerythritol stearate, is often added. However, the addition of the existing lubricant makes the material easy to oil out at high temperature. In the present invention, further, the ionic liquid is selected from quaternary phosphonium ionic liquids.

[0040] In the present invention, the inventors have found that the use of ionic liquids, especially quaternary phosphonium ionic liquids, in the present invention can provide the fluidity and processing performance of the system without using existing lubricants, so that the final modified material has excellent comprehensive performance, especially it can also improve the material's anti-bending property to a certain extent, which may be because the ionic liquid can increase the distance between polymer molecules to a certain extent, thereby increasing the plasticity of the material.

[0041] Further, the ionic liquid is selected from C6-C16 tributyl quaternary phosphonium ionic liquids, preferably C12-C14 tributyl quaternary phosphonium ionic liquids, such as at least one of dodecyl tributyl phosphonium tetrafluoroborate, dodecyl tributyl phosphonium bis(trifluoromethanesulfonyl)imide, tetradecyl tributyl phosphonium chloride, tetradecyl tributyl phosphonium bromide, tetradecyl tributyl phosphonium tetrafluoroborate and hexadecyl tributyl phosphonium tetrafluoroborate.

[0042] The use of C12-C14 tributyl quaternary phosphonium ionic liquids in the present invention can further increase the freeze resistance of the modified material, probably because the long chain structure of the ionic liquid can make the polymer chains of the polymer move better, reducing the tendency of the modified material to brittle fracture.

[0043] Furthermore, the metal compound includes metal oxides and metal sulfides.

[0044] Furthermore, the weight ratio of the metal oxide to the metal sulfide is 1:(0.5-1), preferably 1:0.75.

[0045] Furthermore, the metal oxide is selected from at least one of MgO, Al2O3, Y2O3 and ZnO, preferably Y2O3.

[0046] Furthermore, the average particle size of the Y2O3 is 300-400nm, preferably 350nm.

[0047] The Y2O3 in the present invention can be obtained commercially, for example, Y2O3 can be purchased from Qinghe County Chaotai Metal Materials Co., Ltd.

[0048] Furthermore, the metal sulfide is selected from at least one of zinc sulfide, tin sulfide, cadmium sulfide, magnesium sulfide, copper sulfide and tungsten sulfide, preferably tin sulfide.

[0049] Furthermore, the average particle size of the tin sulfide is 100-500 mesh, preferably 200 mesh.

[0050] The tin sulfide in the present invention can be obtained commercially, for example, tin sulfide can be purchased from Qinghe County Chaotai Metal Materials Co., Ltd.

[0051] In the present invention, the inventors found that adding metal oxides and metal sulfides can better increase the heat resistance stability of the composite material. This may be because the synergistic effect of metal oxides and metal sulfides has good structural stability. Metal sulfides, especially tin sulfide, can exhibit a layered structure in the system. At the same time, a stable structure is formed between the structure of Y2O3 and the layered structure of tin sulfide. These stable structures exist stably between the polymer matrix, thereby better increasing the stability of the modified material, especially making the modified material have better stability in a humid and hot environment.

[0052] The antioxidant described in the present invention can be any antioxidant in the art. Further, the antioxidant is selected from at least one of antioxidant 1010, antioxidant BHT, antioxidant DSTP, antioxidant 168 and antioxidant 264. Antioxidant 1010 is used as an example in the present invention.

[0053] Furthermore, the preparation method of the bending-resistant polycarbonate modified material comprises: mixing polycarbonate, thermoplastic elastomer, modified molecular sieve, ionic liquid, metal compound and antioxidant and then granulating.

[0054] When preparing the polycarbonate modified material, there is no special restriction on the mixing conditions as long as the materials can be mixed evenly, and no further elaboration will be given here.

[0055] Furthermore, the granulation is carried out in a twin-screw extruder, the temperature of the conveying section of the twin-screw extruder is 220-230°C, the temperature of the plasticizing section is 260-270°C, the temperature of the metering section is 255-265°C, the screw speed is controlled to be 400-500rpm, and the vacuum degree of the vacuum device of the twin-screw metering section is controlled to be -0.8 to -0.9bar, followed by strip drawing, water cooling, air drying, pelletizing and drying.

[0056] Furthermore, the second aspect of the present invention provides the use of the bending-resistant polycarbonate modified material described in the first aspect of the present invention in an electrical appliance housing or a mobile phone housing.

[0057] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0058] In the present invention, the raw material components such as polycarbonate, thermoplastic elastomer, modified molecular sieve, compatibilizer, ionic liquid and metal compound work synergistically with each other, so that the bending-resistant polycarbonate modified material has excellent toughness, namely, bending resistance and antifreeze resistance as well as moisture-heat resistance. This may be because the present invention first controls the thermoplastic elastomer and polycarbonate so that the polymer matrix has excellent toughness, and at the same time uses the modified molecular sieve to achieve a synergistic toughening effect; at the same time, the modified molecular sieve and the metal compound make the modified material more stable, and the ionic liquid can make the polymer high molecular chain move better, thereby reducing the tendency of the modified material to undergo brittle fracture. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Example 1

[0061] This embodiment provides a bending-resistant polycarbonate modified material. The raw materials of the modified material are, by weight: 86 parts of polycarbonate, 15 parts of thermoplastic elastomer, 8.5 parts of modified molecular sieve, 1.8 parts of compatibilizer, 4.5 parts of ionic liquid, 1.3 parts of metal compound, and 0.1 parts of antioxidant;

[0062] The preparation method of the modified molecular sieve comprises: (1) mixing the molecular sieve, ammonia water and water, filtering and solid phase drying to obtain a molecular sieve intermediate; (2) calcining the molecular sieve intermediate to obtain the modified molecular sieve;

[0063] The molecular sieve was ZSM-5 molecular sieve purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with an average particle size of 0.75 μm and a silicon-aluminum ratio of 25;

[0064] In step (1), the mixing conditions include: temperature of 60° C., rotation speed of 1200 rpm, and time of 45 min;

[0065] In step (1), the weight ratio of molecular sieve to ammonia water is 1:6; the weight ratio of molecular sieve to water is 1:35; the concentration of ammonia water is 13.33 mol / L; the drying conditions are: temperature is 110° C., and the drying time is 6 hours;

[0066] In step (2), the calcination conditions are: calcination at 450° C. for 4 hours in an air atmosphere;

[0067] The melt flow rate of polycarbonate at 300°C and 1.2kg is 15g / 10min, and the model is Shandong Luxi Chemical LXTY1615;

[0068] Thermoplastic elastomer is a combination of POE and SBS; the weight ratio of POE to SBS is 1:0.45; the melt flow rate of POE at 190°C and 2.16kg is 0.5g / 10min, and the model is ENGAGE TM 8150; The melt flow rate of SBS at 190°C and 5kg is 1.4g / 10min, model 2100D;

[0069] The compatibilizer is a combination of styrene-maleic anhydride copolymer and POE grafted maleic anhydride; the weight ratio of styrene-maleic anhydride copolymer to POE grafted maleic anhydride is 1:2; styrene-maleic anhydride copolymer was purchased from Jiayirong Polymer (Shanghai) Co., Ltd., model SAM-020; POE grafted maleic anhydride was purchased from Jiayirong Polymer (Shanghai) Co., Ltd., model EMI-100;

[0070] The ionic liquid is hexadecyltributylphosphonium tetrafluoroborate;

[0071] The metal compound is a metal oxide and a metal sulfide; the weight ratio of the metal oxide to the metal sulfide is 1:0.75; the metal oxide is Y2O3, the average particle size of Y2O3 is 350nm, and Y2O3 is purchased from Qinghe Chaotai Metal Materials Co., Ltd.; the metal sulfide is tin sulfide; the average particle size of tin sulfide is 200 mesh, and tin sulfide is purchased from Qinghe Chaotai Metal Materials Co., Ltd.;

[0072] The antioxidant is antioxidant 1010;

[0073] The preparation method of the bending-resistant polycarbonate modified material comprises: mixing polycarbonate, thermoplastic elastomer, modified molecular sieve, compatibilizer, ionic liquid, metal compound and antioxidant and then granulating;

[0074] The granulation is carried out in a twin-screw extruder. The temperature of the conveying section of the twin-screw extruder is 210°C, the temperature of the plasticizing section is 265°C, the temperature of the metering section is 260°C, the screw speed is controlled to be 420rpm, and the vacuum degree of the vacuum device of the twin-screw metering section is controlled to be -0.8bar. Then the pellets are pulled, water-cooled, air-dried, pelletized and dried.

[0075] Example 2

[0076] This embodiment provides a bending-resistant polycarbonate modified material. The raw materials of the modified material are, by weight: 90 parts of polycarbonate, 18 parts of thermoplastic elastomer, 8 parts of modified molecular sieve, 2 parts of compatibilizer, 5 parts of ionic liquid, 1.5 parts of metal compound, and 0.06 parts of antioxidant;

[0077] The preparation method of the modified molecular sieve comprises: (1) mixing an acidic molecular sieve, ammonia water and water, filtering and solid phase drying to obtain a molecular sieve intermediate; (2) calcining the molecular sieve intermediate to obtain a modified molecular sieve;

[0078] The molecular sieve was ZSM-5 molecular sieve purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with an average particle size of 0.75 μm and a silicon-aluminum ratio of 25;

[0079] In step (1), the mixing conditions include: temperature of 70° C., rotation speed of 1000 rpm, and time of 30 min;

[0080] In step (1), the weight ratio of the acidic molecular sieve to ammonia water is 1:8; the weight ratio of the acidic molecular sieve to water is 1:40; the concentration of ammonia water is 13.33 mol / L; the drying conditions are a temperature of 120° C. and a drying time of 7 hours;

[0081] In step (2), the calcination conditions are calcination at 500° C. for 2 hours in an air atmosphere;

[0082] The melt flow rate of polycarbonate at 300°C and 1.2kg is 15g / 10min, and the model is Shandong Luxi Chemical LXTY1615;

[0083] Thermoplastic elastomer is a combination of POE and SBS; the weight ratio of POE to SBS is 1:0.4; the melt flow rate of POE at 190°C and 2.16kg is 0.5g / 10min, and the model is ENGAGE TM 8150; The melt flow rate of SBS at 190°C and 5kg is 1.4g / 10min, model 2100D;

[0084] The compatibilizer is a combination of styrene-maleic anhydride copolymer and POE grafted maleic anhydride; the weight ratio of styrene-maleic anhydride copolymer to POE grafted maleic anhydride is 1:3; styrene-maleic anhydride copolymer was purchased from Jiayirong Polymer (Shanghai) Co., Ltd., model SAM-020; POE grafted maleic anhydride was purchased from Jiayirong Polymer (Shanghai) Co., Ltd., model EMI-100;

[0085] The ionic liquid is selected from quaternary phosphonium ionic liquids; the ionic liquid is dodecyl tributyl phosphonium tetrafluoroborate;

[0086] The metal compound is a metal oxide and a metal sulfide; the weight ratio of the metal oxide to the metal sulfide is 1:1; the metal oxide is Y2O3, the average particle size of Y2O3 is 350nm, and Y2O3 is purchased from Qinghe County Chaotai Metal Materials Co., Ltd.; the metal sulfide is tin sulfide; the average particle size of tin sulfide is 200 mesh, and tin sulfide is purchased from Qinghe County Chaotai Metal Materials Co., Ltd.;

[0087] The antioxidant is antioxidant 1010;

[0088] The preparation method of the bending-resistant polycarbonate modified material comprises: mixing polycarbonate, thermoplastic elastomer, modified molecular sieve, compatibilizer, ionic liquid, metal compound and antioxidant and then granulating;

[0089] The granulation is carried out in a twin-screw extruder. The temperature of the conveying section of the twin-screw extruder is 230°C, the temperature of the plasticizing section is 270°C, the temperature of the metering section is 255°C, the screw speed is controlled to be 500rpm, and the vacuum degree of the vacuum device of the twin-screw metering section is controlled to be -0.8bar. Then the product is stretched, water-cooled, air-dried, pelletized and dried.

[0090] Comparative Example 1

[0091] The difference between this comparative example and Example 1 is:

[0092] The modified molecular sieve was replaced with the molecular sieve in Example 1 (ZSM-5 molecular sieve).

[0093] Comparative Example 2

[0094] The difference between this comparative example and Example 1 is:

[0095] The thermoplastic elastomer is POE.

[0096] Comparative Example 3

[0097] The difference between this comparative example and Example 1 is:

[0098] The thermoplastic elastomer is SBS.

[0099] Comparative Example 4

[0100] The difference between this comparative example and Example 1 is:

[0101] The ionic liquid was replaced by pentaerythritol stearate.

[0102] Comparative Example 5

[0103] The difference between this comparative example and Example 1 is:

[0104] The ionic liquid is octyltributylphosphonium trifluoroacetate.

[0105] Comparative Example 6

[0106] The difference between this comparative example and Example 1 is:

[0107] The metal compound is 0 parts, and the modified molecular sieve is 9.8 parts.

[0108] Comparative Example 7

[0109] The difference between this comparative example and Example 1 is:

[0110] The metal compound is a metal sulfide.

[0111] Comparative Example 8

[0112] The difference between this comparative example and Example 1 is:

[0113] The metal compound is a metal oxide.

[0114] Performance Testing

[0115] 1. Room temperature IZOD impact strength: the test standard is ASTM D256-2010, the test environment is 25±2℃ for 48h, and the sample size is 63.5*12.7*3.2mm. The higher the room temperature IZOD impact strength, the better the toughness and the better the bending resistance.

[0116] 2. Low-temperature IZOD impact strength: The test standard is ASTM D256-2010, the test environment is -40±2℃ for 12h, and the sample size is 63.5*12.7*3.2mm. A high low-temperature IZOD impact strength indicates that the low-temperature toughness is better and the frost resistance is better.

[0117] 3. Moisture and heat aging resistance evaluation: The above samples were placed in a constant temperature and humidity aging box at 85°C and 85% RH for 1000 hours. After aging, ASTM D256-2010 was used to test the aging IZOD impact strength of the aged samples and whether there was any floating oil on the surface of the aged samples.

[0118] 4. Light transmittance test: The test standard is GB / T 2410-2008, and the test thickness is 2mm.

[0119] The test results are shown in Table 1:

[0120] Table 1 Performance test results

[0121]

[0122]

[0123] It can be seen from the above performance test results that the polycarbonate modified materials in Examples 1-2 have excellent toughness, namely, bending resistance, frost resistance, moisture and heat resistance, and optical properties, especially the comprehensive performance of Example 1 is the most outstanding. It is speculated that the thermoplastic elastomer and polycarbonate are first controlled to make the polymer matrix have excellent toughness, and the modified molecular sieve is used to achieve a synergistic toughening effect; at the same time, the modified molecular sieve and the metal compound make the modified material more stable, and the ionic liquid can make the polymer chain of the polymer move better, reducing the tendency of the modified material to brittle fracture. However, the comparative examples are significantly inferior to the embodiments in the corresponding performance tests because they do not adopt the necessary technical solutions. In comparative example 1, unmodified molecular sieves are used, and the overall performance of the final polycarbonate modified material is reduced, especially the light transmittance is significantly reduced, indicating that the modified molecular sieves in the present invention can improve the overall performance of the polycarbonate modified material in the present invention; in comparative example 2, the thermoplastic elastomer is only POE without SBS, and the room temperature IZOD impact strength of the final polycarbonate modified material is reduced, and its light transmittance is also reduced; in comparative example 3, the thermoplastic elastomer is only SBS without POE, and the room temperature IZOD impact strength of the final polycarbonate modified material is reduced, and its light transmittance remains basically unchanged, indicating that in the system of the present invention, POE and SBS can play a synergistic toughening role on the material, and also indicating that the addition of SBS in the system of the present invention plays a positive role in the optical properties of the modified material of the present invention; in comparative example 4, the ionic liquid is replaced by quaternary ammonium Tetrastearate, the low-temperature toughness of the modified material decreases significantly, and there is floating oil on the test surface, which shows that the ionic liquid in the system of the present invention can increase the antifreeze property of the modified material and can improve the defect of the existing lubricant that there is floating oil; in comparative example 5, the ionic liquid is octyltributylphosphonium trifluoroacetate, and the low-temperature toughness of the modified material decreases to a certain extent, indicating that the ionic liquid of the specific chain length in the present invention is more conducive to increasing the antifreeze property of the modified material; in comparative example 6, no metal compound is used, and the resistance to wet heat aging of the modified material is reduced; in comparative example 7, the metal compound is a metal sulfide, and the resistance to wet heat aging of the modified material is reduced to a certain extent; in comparative example 8, the metal compound is a metal oxide, and the resistance to wet heat aging of the modified material is reduced to a certain extent, indicating that the addition of the metal compound in the present invention is beneficial to improving the resistance to wet heat aging of the modified material, especially the synergistic effect of metal sulfide and metal oxide can better improve the resistance to wet heat aging of the modified material.

[0124] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A bending-resistant polycarbonate modified material, characterized in that: The raw materials of the modified material include, by weight: 80-90 parts of polycarbonate, 12-18 parts of thermoplastic elastomer, 8-10 parts of modified molecular sieve, 1-2 parts of compatibilizer, 3-5 parts of ionic liquid, 1-1.5 parts of metal compound, and 0.06-0.2 parts of antioxidant; the preparation method of the modified molecular sieve includes: (1) mixing the molecular sieve, ammonia water and water, filtering, and solid phase drying to obtain a molecular sieve intermediate; and (2) calcining the molecular sieve intermediate to obtain the modified molecular sieve.

2. The polycarbonate modified material according to claim 1, characterized in that: The molecular sieve is at least one of MCM-41 molecular sieve, ZSM-5 molecular sieve, MCM-22 molecular sieve, SBA-15 molecular sieve and Y-type molecular sieve; the average particle size of the molecular sieve is 0.1-2 μm; the silicon-aluminum ratio of the molecular sieve is 10-50.

3. The polycarbonate modified material according to claim 1, characterized in that: In step (1), the mixing conditions include: temperature of 50-70°C, rotation speed of 1000-1500 rpm, and time of 35-50 min; the weight ratio of the molecular sieve to ammonia water is 1:(5-8); the weight ratio of the molecular sieve to water is 1:(30-40); the concentration of ammonia water is 13.33-14.84 mol / L; in step (2), the calcination conditions include: calcination at 400-500°C for 2-5 hours in an air atmosphere.

4. The polycarbonate modified material according to claim 1, characterized in that: The polycarbonate has a melt flow rate of 10-20 g / 10 min at 300° C. and 1.2 kg.

5. The polycarbonate modified material according to claim 1, characterized in that: The thermoplastic elastomer is selected from at least one of POE, SEBS, SBS and TPU.

6. The polycarbonate modified material according to claim 1, characterized in that: The compatibilizer is selected from at least one of styrene-maleic anhydride copolymer, POE grafted maleic anhydride and POE grafted glycidyl methacrylate.

7. The polycarbonate modified material according to claim 1, characterized in that: The ionic liquid is selected from C6-C16 tributyl quaternary phosphonium ionic liquids.

8. The polycarbonate modified material according to claim 1, characterized in that: The metal compounds include metal oxides and metal sulfides.

9. The polycarbonate modified material according to claims 1-8, characterized in that: The preparation method of the bending-resistant polycarbonate modified material comprises: mixing polycarbonate, thermoplastic elastomer, modified molecular sieve, ionic liquid, metal compound and antioxidant and then granulating.

10. Use of the polycarbonate modified material according to any one of claims 1 to 9 in an electrical appliance housing or a mobile phone housing.

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