A polycarbonate alloy material with good color stability and a preparation method and application thereof

Abstract

This invention relates to a polycarbonate alloy material with good color stability, its preparation method, and its applications. The polycarbonate alloy material with good color stability is characterized by comprising the following components in parts by weight: 50-90 parts polycarbonate, 1-20 parts acrylonitrile-butadiene-styrene copolymer, 5-20 parts flame retardant, 1-25 parts toughening agent, 0.1-2 parts stabilizer, and 0.1-5 parts anti-dripping agent. This polycarbonate alloy material not only exhibits good thin-wall flame retardancy but also demonstrates high tensile strength retention and significantly improved browning characteristics after long-term thermo-oxidative aging, making it suitable for a wide range of applications.

Description

Technical Field

[0001] This invention relates to the field of plastics technology, and more specifically, to a polycarbonate alloy material with good color stability, its preparation method, and its application. Background Technology

[0002] PC / ABS alloy material is a compound of polycarbonate and acrylonitrile-butadiene-styrene copolymer. It combines the excellent properties of both materials, including the moldability of acrylonitrile-butadiene-styrene copolymer and the mechanical properties, impact strength and temperature resistance of polycarbonate. It can be widely used in automotive interior parts, business machines, communication equipment, home appliances and lighting equipment.

[0003] PC / ABS alloys contain a PB phase, whose olefinic structure is prone to thermo-oxidative aging under heat and oxygen, exhibiting autocatalytic activity. The longer the aging time, the more severe the browning becomes. This not only affects the application range of materials used in external parts due to aesthetic issues, but also indicates greater exposure to heat and oxygen, further accelerating the thermo-oxidative degradation of the resin and causing a rapid decline in mechanical properties. This is a drawback of using PC / ABS alloys in high-temperature (90–130℃) environments. Furthermore, the tensile strength of PC / ABS alloys decreases significantly at high temperatures, also impacting their usability.

[0004] A Chinese patent entitled "An Improvement of Yellowing of PC / ABS Material Composition" studies the color difference problem of PC / ABS material composition under light conditions, but does not focus on the browning of the material and the decrease in tensile strength under high temperature conditions.

[0005] To address this, it is necessary to resolve the issues of PC / ABS alloy materials easily browning in high-temperature environments and experiencing a significant decrease in tensile strength (with a retention rate of less than 50%). Summary of the Invention

[0006] The primary objective of this invention is to overcome the problems of browning and significant decrease in tensile strength of existing PC / ABS alloy materials in high-temperature environments, and to provide a polycarbonate alloy material with good color stability. This polycarbonate alloy material not only exhibits good thin-wall flame retardancy, but also maintains a high tensile strength retention rate after long-term thermo-oxidative aging, and the browning problem is significantly improved, making it suitable for a wide range of applications.

[0007] A further object of the present invention is to provide a method for preparing the above-mentioned polycarbonate alloy material.

[0008] A further objective of this invention is to provide the application of the above-mentioned polycarbonate alloy material in the preparation of photovoltaic energy products.

[0009] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0010] A polycarbonate alloy material with good color stability comprises the following components in parts by weight:

[0011]

[0012] The toughening agent is a core-shell structure toughening agent, wherein the ratio of shell thickness to core diameter is 1:(5-30), and the core of the core-shell structure toughening agent is polydimethylsiloxane and acrylate, and the silicon content of the core-shell structure toughening agent is 8-80 wt%.

[0013] Through extensive research, the inventors of this invention discovered that adding a specific toughening agent to materials using polycarbonate and acrylonitrile-butadiene-styrene copolymer as the matrix resin can not only improve the tensile strength retention rate of polycarbonate alloy materials after long-term thermo-oxidative aging, but also alleviate the browning problem after long-term thermo-oxidative aging. The reason is that by controlling the ratio of the shell thickness to the core diameter of the toughening agent within a certain range, the compatibility between the toughening agent and the matrix resin can be improved. On the one hand, good compatibility forms a stable structure, improving the tensile strength retention rate of the polycarbonate alloy material after long-term thermo-oxidative aging; on the other hand, silicone rubber composed of polydimethylsiloxane and acrylate exhibits excellent color stability during thermo-oxidative aging. Good compatibility is beneficial to the distribution of the toughening agent, and further control of the silicon content of the toughening agent can significantly improve the browning problem of polycarbonate alloy materials after long-term thermo-oxidative aging.

[0014] In addition, this polycarbonate alloy material also has good thin-wall flame retardancy.

[0015] The polycarbonate alloy material of this invention not only has good thin-wall flame retardancy, but also has a high tensile strength retention rate after long-term thermo-oxidative aging and the browning problem is significantly improved, making it suitable for a wide range of applications.

[0016] Preferably, the polycarbonate alloy material comprises the following components in parts by weight:

[0017]

[0018]

[0019] Preferably, the ratio of the shell thickness to the core diameter of the core-shell toughening agent is 1:(6-25).

[0020] Preferably, the core-shell toughening agent has a silicon content of 30–80 wt%.

[0021] Preferably, the shell of the core-shell toughening agent is an acrylate.

[0022] Commonly used acrylonitrile-butadiene-styrene copolymers, polycarbonates, stabilizers, flame retardants, and anti-dripping agents in this invention can all be used in this invention.

[0023] Preferably, the acrylonitrile-butadiene-styrene copolymer is obtained by bulk polymerization.

[0024] Preferably, the polycarbonate has an average molecular weight of 21,000 to 33,650.

[0025] Preferably, the stabilizer is composed of a metal passivating agent, a hindered phenolic antioxidant, and a glycidyl methacrylate-grafted styrene-acrylonitrile copolymer in a mass ratio of 1:(1-3):(1-8).

[0026] The introduction of glycidyl methacrylate-grafted styrene-acrylonitrile copolymer further enhances the dispersion of toughening agent and ABS, making it more conducive to the distribution of toughening agent in the matrix resin. On this basis, the presence of GMA active functional groups can end-cap the PC resin, reduce the generation rate and content of quinone chromophores in the thermo-oxidative reaction of PC, and improve the performance stability after aging. At the same time, it has the effect of improving the color stability of double bonds in ABS and inhibiting the thermo-oxidative reaction rate of double bonds. Meanwhile, the metal passivator weakens the catalytic effect of metal impurities that are inevitably present in the material during raw materials, processing and use, thereby slowing down the thermo-oxidative degradation reaction. The hindered phenolic antioxidant can capture peroxide free radicals. Through the synergistic effect of metal passivator, hindered phenolic antioxidant and glycidyl methacrylate-grafted styrene-acrylonitrile copolymer, not only is the stabilizing effect of the stabilizer further enhanced, but the thermo-oxidative aging reaction rate of the material is also further slowed down.

[0027] Optionally, the metal passivating agent is at least one of an organic acid or a phosphite of thiobisphenol A and melamine.

[0028] Alternatively, the organic acid may be citric acid.

[0029] Optionally, the hindered phenolic antioxidant is at least one of antioxidant 1010, antioxidant 1098, or antioxidant 1076.

[0030] Optionally, the flame retardant includes, but is not limited to, phosphorus-based flame retardants; the phosphorus-based flame retardants include, but are not limited to, TPP, BDP, RDP, or RDX.

[0031] Optionally, the anti-dripping agent includes, but is not limited to, fluoropolymers; the fluoropolymers include, but are not limited to, SAN-coated PTFE, MMA-coated PTFE, silicone-coated PTFE, pure PTFE powder, or PTFE emulsion.

[0032] To obtain other properties, the polycarbonate alloy material of the present invention may also contain 0.5 to 8 parts of other additives.

[0033] Optionally, the other additives are at least one of fillers or lubricants.

[0034] Preferably, the filler is at least one of glass fiber or mineral filler.

[0035] Preferably, the lubricant is at least one of stearate or oxidized polyolefin wax.

[0036] The preparation method of the above-mentioned polycarbonate alloy material includes the following steps: mixing the components, melt extruding, and granulating to obtain the polycarbonate alloy material.

[0037] More preferably, the stirring speed is 30-80 rpm; the length-to-diameter ratio of the twin-screw extruder is 35-60:1, the barrel temperature is 220-260℃, and the screw speed is 200-800 rpm.

[0038] The application of the aforementioned polycarbonate alloy material in the preparation of photovoltaic energy products is also within the scope of protection of this invention.

[0039] Preferably, the photovoltaic energy product is a photovoltaic inverter module or an energy storage module.

[0040] Compared with the prior art, the beneficial effects of the present invention are:

[0041] The polycarbonate alloy material of the present invention not only has good thin-wall flame retardancy, but also has a high tensile strength retention rate after long-term thermo-oxidative aging and the browning problem is significantly improved, making it suitable for a wide range of applications. Detailed Implementation

[0042] To more clearly and completely describe the technical solution of the present invention, the present invention will be further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. Various changes can be made within the scope of the claims of the present invention.

[0043] The reagents used in the various embodiments and comparative examples of this invention are described below:

[0044] Polycarbonate 1#: PC-10NP, LG Korea, average molecular weight 24500;

[0045] Polycarbonate 2#: 7030PJ, Samyang, South Korea, average molecular weight 33650;

[0046] Polycarbonate 3#: PC-22NP, LG Korea, average molecular weight 21000;

[0047] Polycarbonate 4#: FN1500, Idemitsu, Japan, with an average molecular weight of 14300;

[0048] Acrylonitrile-butadiene-styrene copolymer 1#: obtained by bulk polymerization, with an average molecular weight of 17,000 and an acrylonitrile content of 28%, commercially available;

[0049] Acrylonitrile-butadiene-styrene copolymer #2: Obtained by suspension polymerization, with an average molecular weight of 17,000 and an acrylonitrile content of 28%, commercially available;

[0050] Toughening Agent 1#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:6, core component is silicone rubber, shell is acrylate, silicon content is 30wt%, S-2130 Mitsubishi Chemical;

[0051] Toughening agent 2#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:5, core component is silicone rubber, shell is acrylate, silicon content is 10wt%, S-2006 Mitsubishi Chemical;

[0052] Toughening agent 3#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:30, core component is silicone rubber, shell is acrylate, silicon content is 80wt%, SX005, Mitsubishi Chemical;

[0053] Toughening agent 4#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:8, core component is silicone rubber, shell is acrylate, silicon content is 8wt%, S-2001, Mitsubishi Chemical;

[0054] Toughening Agent 5#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:25, core component is silicone rubber, shell is acrylate, silicon content is 80wt%, SX005 Mitsubishi Chemical

[0055] Toughening agent 6#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:8, core component is silicone rubber, shell is SAN type, silicon content is 8wt%, S2260, Mitsubishi Chemical;

[0056] Toughening agent 7#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:4, core component is silicone rubber, shell is acrylate, silicon content is 8wt%; S-2501 Mitsubishi Chemical;

[0057] Toughening agent 8#: Core-shell toughening agent, shell thickness to core diameter ratio is 1:6, core component is silicone rubber, shell is acrylate, silicone content is 85wt%, MR01, Kanekachi, Japan;

[0058] Toughening Agent 9#: Core-shell toughening agent, core component is acrylate, shell is acrylate, silicon content is 0%, EXL2330, Dow Chemical;

[0059] Toughening agent 10#: Non-core-shell toughening agent, EMA 1125, DuPont;

[0060] Stabilizer 1#: Citric acid, commercially available;

[0061] Stabilizer 2#: Antioxidant 1010, commercially available;

[0062] Stabilizer 3#: Glycidyl methacrylate grafted styrene-acrylonitrile copolymer, SOG-002, Yijiarong;

[0063] Stabilizer A#: is obtained by mixing stabilizer 1#, stabilizer 2# and stabilizer 3# in a weight ratio of 1:2:5;

[0064] Stabilizer B#: is obtained by mixing stabilizer 1#, stabilizer 2# and stabilizer 3# in a weight ratio of 1:1:1;

[0065] Stabilizer C#: is obtained by mixing stabilizer 1#, stabilizer 2# and stabilizer 3# in a weight ratio of 1:3:8;

[0066] Flame retardant #1: BDP, Edico Japan;

[0067] Flame retardant #2: PX-200, Daihachi, Japan;

[0068] Anti-dripping agent: FP-100, Fushimi, Japan;

[0069] Other additives: lubricants, stearates, commercially available;

[0070] Unless otherwise specified, all components (e.g., anti-dripping agents, other additives) used in each parallel embodiment and comparative example are the same commercially available products.

[0071] The polycarbonate alloy materials provided in the embodiments and comparative examples of this invention were subjected to performance testing according to the following test methods:

[0072] Tensile strength and retention rate: Test specimens were prepared according to ASTM D638-2017 and TYPE I requirements via injection molding or hot pressing. Five prepared specimens were placed at 25°C and 50% humidity for 40-72 hours before testing. The testing speed was 50 mm / min, and the maximum load was 10 kN. The average tensile breaking strength of the five specimens was calculated as the initial tensile strength. The specimens were then placed in a 130°C oven for a fixed aging time, removed, and placed at 25°C and 50% humidity for 40-72 hours before testing. The testing speed was 50 mm / min, and the maximum load was 10 kN. The average tensile breaking strength of the five specimens after aging was calculated as the aging tensile strength, and the tensile strength retention rate was obtained by calculation.

[0073] Color difference: Tested using a colorimeter. Five samples of injection-molded 2.0mm thick, 60mm wide, and 60mm long samples were placed at 25℃ and 50% humidity for 40-72 hours and then tested with a colorimeter (instrument model: [instrument name], light source: [light source]) to obtain the initial color difference value. The samples were then placed in a 130℃ constant temperature oven for a fixed aging time and then removed and placed at 25℃ and 50% humidity for 40-72 hours. The samples were then tested in five different areas on the same test plate, and the color difference was calculated.

[0074] Flame retardant performance: Flame retardancy testing was conducted according to the "Flammability Testing of Plastic Materials, UL 94" standard. The vertical flammability rating was determined based on the burning rate, extinguishing time, resistance to drop, and whether the drop was positively burning. The sample used for testing was 125mm long and 13mm wide. In this invention, the thickness was selected as 1.5mm for testing. According to the UL 94 standard, the flame retardancy rating of the material can be classified as UL 94-HB, V0, V1, and V2.

[0075] Flowability: expressed as melt flow rate, with a load of 5 kg and a test temperature of 245 °C selected according to ASTM D1238-2018.

[0076] The preparation process of the polycarbonate alloy materials in the embodiments and comparative examples of the present invention is as follows: Each component is weighed according to the specified ratio, added to a high-speed mixer for stirring and mixing to obtain a premix. This premix is ​​then extruded in a twin-screw extruder, and after a melt granulation process, the polycarbonate alloy material is obtained. The stirring speed is 50 rpm, the length-to-diameter ratio of the twin-screw extruder is 48:1, the barrel temperature is 220°C, and the screw speed is 350 rpm.

[0077] Examples 1-21

[0078] Examples 1-21 provide a series of polycarbonate alloy materials, the formulations of which are shown in Tables 1 and 2.

[0079] Table 1. Formulations (parts by weight) for Examples 1-11

[0080]

[0081] Table 2. Formulations (parts by weight) for Examples 12-21

[0082]

[0083]

[0084] Comparative Example 1

[0085] This comparative example provides a polycarbonate alloy material whose formulation differs from that of Example 1 in that toughening agent 1# is replaced with an equal amount of toughening agent 7#.

[0086] Comparative Example 2

[0087] This comparative example provides a polycarbonate alloy material whose formulation differs from that of Example 1 in that toughening agent 1# is replaced with an equal amount of toughening agent 8#.

[0088] Comparative Example 3

[0089] This comparative example provides a polycarbonate alloy material whose formulation differs from that of Example 1 in that toughening agent 1# is replaced with an equal amount of toughening agent 9#.

[0090] Comparative Example 4

[0091] This comparative example provides a polycarbonate alloy material whose formulation differs from that of Example 1 in that toughening agent 1# is replaced with an equal amount of toughening agent 10#.

[0092] Comparative Example 5

[0093] This comparative example provides a polycarbonate alloy material whose formulation differs from that of Example 1 in that toughening agent 1# is not added.

[0094] The properties of the polycarbonate alloy materials of each embodiment and comparative example were determined according to the test methods mentioned above, and the test results are shown in Table 3.

[0095] Table 3. Performance test results of polycarbonate alloy materials in each embodiment and comparative example.

[0096]

[0097]

[0098] As shown in Table 3, the polycarbonate alloy materials of Examples 1 to 21 have good flame retardant properties (V-0 grade), high tensile strength retention rate (greater than 50%) after long-term thermo-oxidative aging, and significantly improved browning problem (color difference less than 5).

[0099] Examples 1-5 show that the dosage of each component has a certain impact on tensile strength, tensile strength after long-term thermo-oxidative aging, and color difference. In Examples 1, 3, 4, and 5, the polycarbonate dosage is relatively high. During the thermo-oxidative aging process, the polycarbonate undergoes Fries rearrangement under the combined action of heat and oxygen, leading to an increase in the cross-linked structure content, resulting in a tensile strength retention rate exceeding 100%. Under the comprehensive control of each component, Example 1 exhibits the highest tensile strength retention rate and the smallest color difference. The color differences in Examples 4 and 5 are smaller than those in Examples 2 and 3, and the improvement in browning is more significant (smaller color difference).

[0100] As can be seen from Examples 1 and 7-9, when the average molecular weight of polycarbonate is within a suitable range (21,000-33,650), the compatibility between the toughening agent and the matrix resin can be further improved, the aging tensile strength retention rate of polycarbonate alloy materials is higher, and the browning problem is improved more significantly (with smaller color difference).

[0101] As can be seen from Examples 1 and 10, the acrylonitrile-butadiene-styrene copolymer synthesized by the bulk method has a more suitable glue content, better compatibility with the toughening agent, and a more stable structure formed by the toughening agent and the matrix resin. As a result, the polycarbonate alloy material obtained by the bulk method has a higher aging tensile strength retention rate and a more significant improvement in browning problem (smaller color difference).

[0102] As can be seen from Examples 1 and 11, using a specific phosphorus-based flame retardant can result in a higher retention rate of aging tensile strength and a more significant improvement in browning issues (smaller color difference) in the obtained polycarbonate alloy material.

[0103] As can be seen from Examples 1, 12-16, when the ratio of shell thickness to core diameter is 1:(6-30) and the shell is made of acrylate (Examples 1, 13, 14 and 15), the polycarbonate alloy material exhibits higher retention of aging tensile strength and more significant improvement in browning issues (smaller color difference).

[0104] As can be seen from Examples 1, 12, 13, and 15, when the ratio of shell thickness to core diameter is 1:(6-30) and the silicon content of the core-shell toughening agent is 30-80 wt% (Examples 1, 13, and 15), the aging tensile strength retention rate of polycarbonate alloy materials is higher.

[0105] As can be seen from Examples 1, 17-21, when a composite stabilizer is used (Examples 1, 17 and 18), the polycarbonate alloy material exhibits higher retention of aging tensile strength and more significant improvement in browning issues (smaller color difference).

[0106] In Comparative Example 1, the ratio of shell thickness to core diameter of the toughening agent was too large, resulting in a significant decrease in tensile strength of the polycarbonate alloy material after long-term thermo-oxidative aging (retention rate less than 50%). In Comparative Example 2, the silicon content of the toughening agent was too high, resulting in a significant decrease in tensile strength of the polycarbonate alloy material after long-term thermo-oxidative aging (retention rate less than 50%), and the browning problem was not well improved (color difference greater than 5). In Comparative Examples 3 and 4, the toughening agents were unsuitable, resulting in a significant decrease in tensile strength of the polycarbonate alloy material after long-term thermo-oxidative aging (retention rate less than 50%), and the browning problem was not well improved (color difference greater than 5). In Comparative Example 5, no toughening agent was added, resulting in a significant decrease in tensile strength of the polycarbonate alloy material after long-term thermo-oxidative aging (retention rate less than 50%), and the browning problem was not well improved (color difference greater than 5).

[0107] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A polycarbonate alloy material with good color stability, characterized in that, The components include the following parts by weight: 50-90 parts polycarbonate 1-20 parts of acrylonitrile-butadiene-styrene copolymer 5-20 parts flame retardant Toughening agent 1-25 parts, Stabilizer 0.1~2 parts, Anti-dripping agent 0.1-5 parts; The toughening agent is a core-shell structure toughening agent, wherein the ratio of shell thickness to core diameter is 1:(5~30), and the core of the core-shell structure toughening agent is silicone rubber, the shell is acrylate, and the silicon content of the core-shell structure toughening agent is 8~80 wt%. The stabilizer is composed of a metal passivating agent, a hindered phenolic antioxidant, and a glycidyl methacrylate-grafted styrene-acrylonitrile copolymer in a mass ratio of 1:(1~3):(1~8); The metal passivating agent is citric acid; The hindered phenolic antioxidant is at least one of antioxidant 1010, antioxidant 1098, or antioxidant 1076.

2. The polycarbonate alloy material according to claim 1, characterized in that, The polycarbonate alloy material comprises the following components in parts by weight: 60-85 parts polycarbonate 3-10 parts of acrylonitrile-butadiene-styrene copolymer 7-10 parts flame retardant 3-10 parts toughening agent, Stabilizer 0.25~1.2 parts, 0.3 to 0.8 parts of anti-dripping agent.

3. The polycarbonate alloy material according to claim 1, characterized in that, The ratio of the shell thickness to the core diameter of the core-shell toughening agent is 1:(6~30).

4. The polycarbonate alloy material according to claim 1, characterized in that, The core-shell toughening agent has a silicon content of 30-80 wt%.

5. The polycarbonate alloy material according to claim 1, characterized in that, The flame retardant is a phosphorus-based flame retardant.

6. The polycarbonate alloy material according to claim 1, characterized in that, The acrylonitrile-butadiene-styrene copolymer was obtained by bulk polymerization.

7. The polycarbonate alloy material according to claim 1, characterized in that, The polycarbonate has an average molecular weight of 21,000 to 33,650.

8. A method for preparing the polycarbonate alloy material according to any one of claims 1 to 7, characterized in that, The process includes the following steps: mixing the components, melting and extruding, and granulating to obtain the polycarbonate alloy material.

9. The application of the polycarbonate alloy material according to any one of claims 1 to 7 in the preparation of photovoltaic energy products.

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