Polycarbonate alloy material with good color stability, and its preparation method and use

Abstract

The present invention relates to a polycarbonate alloy material with good color stability, as well as its preparation and use. The polycarbonate alloy material with good color stability of the present invention contains, as its components, 50 to 90 parts by weight of polycarbonate, 1 to 20 parts by weight of an acrylonitrile-butadiene-styrene copolymer, 5 to 20 parts by weight of a flame retardant, 1 to 25 parts by weight of a toughener, 0.1 to 2 parts by weight of a stabilizer, and 0.1 to 5 parts by weight of an anti-dripping agent. This polycarbonate alloy material not only has good thin-wall flame retardancy, but also has relatively high tensile strength retention even after long-term thermal oxidative aging. It also has significantly improved browning resistance, broadening its application range.

Description

[Technical Field]

[0001] The present invention relates to the technical field of plastics, more particularly to a polycarbonate alloy material with good color stability, and its preparation method and use. [Background technology]

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

[0003] PC / ABS alloy materials contain a PB phase, whose olefinic structure is prone to thermo-oxidative aging reactions in the presence of heat and oxygen. This autocatalytic effect causes the material to brown more severely as the aging time increases. This cosmetic issue not only impacts the application range of some materials used in exterior components, but the more severe the browning, the greater the impact of heat and oxygen on the material, further accelerating the thermo-oxidative decomposition of the resin and resulting in a rapid deterioration of mechanical properties. This is a drawback when using PC / ABS alloy materials in high-temperature environments (90-130°C). Furthermore, the tensile strength of PC / ABS alloy materials decreases significantly at high temperatures, affecting their use.

[0004] The Chinese patent entitled "PC / ABS material composition with improved yellowing" studies the issue of color difference of the PC / ABS material composition under lighting conditions, but does not focus on the issues of browning of the material's color and reduction of tensile strength under high temperature conditions.

[0005] Therefore, it is necessary to solve the problem that PC / ABS alloy materials are prone to browning in high temperature environments and suffer a significant decrease in tensile strength (retention rate of less than 50%). Summary of the Invention [Problem to be solved by the invention]

[0006] The primary objective of the present invention is to overcome the problems of the aforementioned existing PC / ABS alloy materials, namely their susceptibility to browning and a significant decrease in tensile strength in high-temperature environments, and to provide a polycarbonate alloy material with good color stability. This polycarbonate alloy material not only has good thin-wall flame retardancy, but also a relatively high tensile strength retention rate after long-term thermal oxidative aging, and the browning problem is greatly improved, thereby broadening its application scenarios.

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

[0008] A further object of the present invention is to provide the use of the above polycarbonate alloy material in the manufacture of photovoltaic products. [Means for solving the problem]

[0009] The above object of the present invention is achieved by the following technical solutions.

[0010] A polycarbonate alloy material having good color stability, comprising: 50 to 90 parts by weight of polycarbonate; 1 to 20 parts by weight of an acrylonitrile-butadiene-styrene copolymer; 5 to 20 parts by weight of a flame retardant; 1 to 25 parts by weight of a toughener; 0.1 to 2 parts by weight of a stabilizer; and 0.1 to 5 parts by weight of an anti-dripping agent.

[0011] The toughener has a core-shell structure, and the ratio of the shell thickness to the core diameter of the toughener having a core-shell structure is 1:(5-30). The core of the toughener having a core-shell structure is made of polydimethylsiloxane and acrylate, and the silicon content of the toughener having a core-shell structure is 8-80 wt%.

[0012] After extensive research, the inventors discovered that adding a specific toughener to a material with a polycarbonate and acrylonitrile-butadiene-styrene copolymer matrix resin not only improves the tensile strength retention of polycarbonate alloy materials after long-term thermal oxidative aging, but also alleviates the browning problem of polycarbonate alloy materials after long-term thermal oxidative aging. This is because adjusting the shell thickness to core diameter ratio of the toughener within a certain range improves compatibility between the toughener and the matrix resin. Good compatibility leads to the formation of a stable structure, improving the tensile strength retention of polycarbonate alloy materials after long-term thermal oxidative aging. Silicone rubbers composed of polydimethylsiloxane and acrylate exhibit excellent color stability during thermal oxidative aging. Good compatibility allows for further adjustment of the toughener distribution and silicone content, significantly alleviating the browning problem of polycarbonate alloy materials after long-term thermal oxidative aging.

[0013] Furthermore, the polycarbonate alloy material has better thin-wall flame retardancy.

[0014] That is, the polycarbonate alloy material of the present invention not only has good thin-wall flame retardancy, but also has a relatively high tensile strength retention rate after long-term thermal oxidative aging, and the browning problem is greatly improved, which widens the application range.

[0015] Preferably, the polycarbonate alloy material contains, as components: 60 to 85 parts by weight of polycarbonate; 3 to 10 parts by weight of an acrylonitrile-butadiene-styrene copolymer, 7 to 10 parts by weight of a flame retardant; 3 to 10 parts by weight of a toughener; 0.25 to 1.2 parts by weight of a stabilizer; and 0.3 to 0.8 parts by weight of an anti-dripping agent.

[0016] Preferably, the ratio of the shell thickness to the core diameter of the toughener having a core-shell structure is 1:(6 to 25).

[0017] Preferably, the silicon content of the toughener having a core-shell structure is 30 to 80 wt %. Preferably, the shell of the core-shell toughener is an acrylate.

[0018] In the present invention, acrylonitrile-butadiene-styrene copolymers, polycarbonates, stabilizers, flame retardants, and anti-dripping agents commonly used in the art can be used.

[0019] Preferably, the acrylonitrile-butadiene-styrene copolymer is obtained by bulk polymerization.

[0020] Preferably, the average molecular weight of the polycarbonate is 21,000 to 33,650.

[0021] Preferably, the stabilizer comprises a metal deactivator, a hindered phenolic antioxidant, and a glycidyl methacrylate-grafted styrene-acrylonitrile copolymer in a mass ratio of 1:(1-3):(1-8).

[0022] The addition of glycidyl methacrylate-grafted styrene-acrylonitrile copolymer further enhances the dispersion of the toughener and ABS, promoting better distribution of the toughener in the matrix resin. Based on this, the presence of GMA active functional groups end-caps the PC resin, reducing the rate and content of quinone chromophores generated during the thermal oxidation of PC, improving property stability after aging. It also improves the color stability of double bonds in ABS and inhibits the rate of thermal oxidation of double bonds. Meanwhile, metal passivators (metal deactivators) weaken the catalytic effect of metal impurities inevitably generated in materials during raw materials, processing, and use, slowing the rate of thermal oxidative decomposition. Hindered phenolic antioxidants can capture peroxide free radicals. The synergistic effect of the metal passivators (metal deactivators), hindered phenolic antioxidants, and glycidyl methacrylate-grafted styrene-acrylonitrile copolymer not only further strengthens the stabilizing effect of the stabilizer, but also further slows the rate of thermal oxidative aging of the material.

[0023] Optionally, the metal deactivator is at least one of a phosphite of an organic acid or thiobisphenol, melamine.

[0024] Further optionally, the organic acid is citric acid.

[0025] Optionally, the hindered phenolic antioxidant is at least one of Antioxidant 1010, Antioxidant 1098, or Antioxidant 1076.

[0026] Optionally, the flame retardant includes, but is not limited to, a phosphorus-based flame retardant, and the phosphorus-based flame retardant includes, but is not limited to, TPP, BDP, RDP, or RDX, etc.

[0027] Optionally, the anti-drip agent includes, but is not limited to, a fluorine-containing polymer, including, but not limited to, SAN-coated PTFE, MMA-coated PTFE, silicone-coated PTFE, pure PTFE powder, or PTFE emulsion.

[0028] To obtain other properties, 0.5 to 8 parts of other auxiliary agents may be added to the polycarbonate alloy material of the present invention.

[0029] Optionally, the other auxiliary agent is at least one of a filler or a lubricant.

[0030] Preferably, the filler is at least one of glass fibre or mineral filler.

[0031] Preferably, the lubricant is at least one of stearates or oxidized polyolefin waxes.

[0032] The method for preparing the polycarbonate alloy material includes the steps of mixing the components, melting, extruding and granulating the components to obtain the polycarbonate alloy material.

[0033] More preferably, the rotation speed of the stirring and mixing is 30 to 80 rpm, and the twin screw extruder has an aspect ratio of 35 to 60:1, a barrel temperature of 220 to 260° C., and a screw rotation speed of 200 to 800 rpm.

[0034] The use of the above polycarbonate alloy material in the manufacture of photovoltaic products is also within the scope of protection of the present invention.

[0035] Preferably, the photovoltaic product is a photovoltaic inverter assembly or an energy storage assembly. [Effects of the Invention]

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] The polycarbonate alloy material of the present invention not only has good thin-wall flame retardancy, but also has a relatively high tensile strength retention rate even after long-term thermal oxidative aging, and the problem of browning is greatly improved, which widens the application range. DETAILED DESCRIPTION OF THE INVENTION

[0038] In order to more clearly and completely describe the technical solutions of the present invention, the present invention will be described in more detail below using specific examples. However, it should be understood that the specific examples described here are for illustrating the present invention, but are not for limiting the present invention, and various modifications are possible within the limited scope of the claims of the present invention.

[0039] The following is a description of some of the reagents used in the examples and comparative examples of the present invention.

[0040] Polycarbonate 1#: PC-10NP, LG Corporation, Korea, average molecular weight 24,500 Polycarbonate 2#: 7030PJ, Samyang Co., Ltd., Korea, average molecular weight 33,650 Polycarbonate 3#: PC-22NP, LG Corporation, Korea, average molecular weight 21,000 Polycarbonate 4#: FN1500, Idemitsu Japan, average molecular weight 14,300 Acrylonitrile-butadiene-styrene copolymer 1#: Obtained by bulk polymerization, average molecular weight 17,000, acrylonitrile content 28%, commercially available Acrylonitrile-butadiene-styrene copolymer 2#: Obtained by suspension polymerization, average molecular weight 17,000, acrylonitrile content 28%, commercially available Toughener 1#: Core-shell toughener, shell thickness to core diameter ratio is 1:6, core component is silicone rubber, shell is acrylate, silicone content is 30wt%, S-2130 Mitsubishi Chemical Corporation Toughener 2#: Core-shell toughener, shell thickness to core diameter ratio is 1:5, core component is silicone rubber, shell is acrylate, silicone content is 10wt%, S-2006 Mitsubishi Chemical Corporation Toughener 3#: Core-shell toughener, shell thickness to core diameter ratio is 1:30, core component is silicone rubber, shell is acrylate, silicone content is 80wt%, SX005, Mitsubishi Chemical Corporation Toughener 4#: Core-shell toughener, shell thickness to core diameter ratio is 1:8, core component is silicone rubber, shell is acrylate, silicone content is 8wt%, S-2001, Mitsubishi Chemical Corporation Toughener 5#: Core-shell toughener, shell thickness to core diameter ratio is 1:25, core component is silicone rubber, shell is acrylate, silicone content is 80wt%, SX005 Mitsubishi Chemical Toughener 6#: Core-shell toughener, shell thickness to core diameter ratio is 1:8, core component is silicone rubber, shell is SAN, silicone content is 8wt%, S2260, Mitsubishi Chemical Corporation Toughener 7#: Core-shell toughener, shell thickness to core diameter ratio is 1:4, core component is silicone rubber, shell is acrylate, silicone content is 8wt%, S-2501 Mitsubishi Chemical Corporation Toughener 8#: Core-shell toughener, shell thickness to core diameter ratio is 1:6, core component is silicone rubber, shell is acrylate, silicone content is 85wt%, MR01, Nippon Kanebo Co., Ltd. Toughener 9#: Core-shell toughener, core component is acrylate, shell is acrylate, silicone content is 0%, EXL2330, Dow Chemical Toughener 10#: Non-core-shell toughener, EMA1125, DuPont Stabilizer 1#: Citric acid, commercially available Stabilizer 2#: Antioxidant 1010, commercially available Stabilizer 3#: Glycidyl methacrylate grafted styrene-acrylonitrile copolymer, S0G-002, Yijia Rong Co. Stabilizer A#: Stabilizer 1#, Stabilizer 2#, and Stabilizer 3# mixed in a weight ratio of 1:2:5 Stabilizer B#: Stabilizer 1#, Stabilizer 2#, and Stabilizer 3# mixed in a 1:1:1 weight ratio Stabilizer C#: Stabilizer 1#, Stabilizer 2#, and Stabilizer 3# mixed in a weight ratio of 1:3:8 Flame retardant 1#: BDP, Adeka Japan Flame retardant 2#: PX-200, Nippon Daihachisha Anti-drip agent: FP-100 by Fushimisha Other auxiliaries: lubricants, stearates, commercially available

[0041] Unless otherwise specified, each component (for example, anti-dripping agent, other auxiliary agents) selected in each parallel example and comparative example is the same as that commercially available.

[0042] The properties of the polycarbonate alloy materials provided in the examples and comparative examples of the present invention are measured according to the following test methods.

[0043] Tensile Strength and Tensile Strength Retention: Test specimens were prepared by injection molding or hot pressing in accordance with ASTM D638-2017 Type I requirements. Five specimens were then conditioned at a constant temperature and humidity of 25°C and 50% humidity for 40 to 72 hours, after which testing was performed at a test speed of 50 mm / min and a maximum load of 10 kN. The average of the tensile strengths of the five specimens was calculated as the initial tensile strength. The specimens were then placed in a constant temperature oven at 130°C for a set aging period, after which they were removed and conditioned in a constant temperature and humidity oven at 25°C and 50% humidity for 40 to 72 hours. Testing was then performed at a test speed of 50 mm / min and a maximum load of 10 kN. The average of the tensile strengths of the five specimens after aging was calculated as the tensile strength after aging, and the tensile strength retention was calculated.

[0044] Color difference: Tested using a color difference meter. Five injection-molded specimens measuring 2.0 mm thick, 60 mm wide, and 60 mm long were placed at a constant temperature and humidity of 25°C and 50% for 40-72 hours. Then, the specimens were tested using a color difference meter (instrument model, light source) to obtain the initial color difference value. The specimens were then placed in a 130°C oven for a certain aging period, then removed and placed at a constant temperature and humidity of 25°C and 50% for 40-72 hours. Then, five different areas on the same test board were tested and the color difference was calculated.

[0045] Flame Retardancy: Flame retardancy tests are conducted according to the "Flammability Test for Plastic Materials, UL94" procedure. The vertical flame rating is determined based on the burning rate, extinguishing time, drip prevention ability, and whether or not the material burns when dripped. The test sample is 125 mm long and 13 mm wide. In this invention, the thickness is selected as 1.5 mm during testing. According to the UL94 procedure, the flame retardancy rating of materials can be classified into UL94-HB, V0, V1, and V2.

[0046] Flowability: Expressed as melt flow rate, according to ASTM D1238-2018 requirements, with a load of 5 kg and a test temperature of 245°C.

[0047] The polycarbonate alloy materials of the present invention and comparative examples were prepared as follows: Each component was weighed according to the mixing ratio and then mixed in a high-speed mixer. The resulting premix was then extruded in a twin-screw extruder and melt-granulated to obtain the polycarbonate alloy material. The mixing speed was 50 rpm, the twin-screw extruder aspect ratio was 48:1, the barrel temperature was 220°C, and the screw speed was 350 rpm. Examples 1 to 21

[0048] Examples 1-21 provide a series of polycarbonate alloy materials, the formulations of which are shown in Tables 1 and 2.

[0049] [Table 1]

[0050] [Table 2]

[0051] Comparative Example 1 This comparative example provides a polycarbonate alloy material, the formulation of which is the same as that of Example 1, except that the toughener 1# is replaced with the same amount of toughener 7#.

[0052] Comparative Example 2 This comparative example provides a polycarbonate alloy material, the formulation of which is the same as that of Example 1, except that the toughener 1# is replaced with the same amount of toughener 8#.

[0053] Comparative Example 3 This comparative example provides a polycarbonate alloy material, the formulation of which is the same as that of Example 1, except that the toughener 1# is replaced with the same amount of toughener 9#.

[0054] Comparative Example 4 This comparative example was similar to Example 1, except that a polycarbonate alloy material was provided and toughener 1# was replaced with the same amount of toughener 10#.

[0055] Comparative Example 5 This comparative example provided a polycarbonate alloy material and was similar to Example 1, except that no toughener 1# was added.

[0056] The properties of the polycarbonate alloy materials of each example and comparative example were tested according to the test methods described above, and the test results are shown in Table 3.

[0057] [Table 3]

[0058] Table 3 shows that the polycarbonate alloy materials of Examples 1 to 21 have good flame retardancy (V-0 class), good tensile strength retention after long-term thermal oxidative aging (over 50%), and the problem of browning has been significantly improved (color difference less than 5).

[0059] Examples 1 to 5 demonstrated that the amount of each component used had a certain effect on tensile strength, tensile strength after long-term thermal oxidative aging, and color difference. Among these, Examples 1, 3, 4, and 5 used relatively large amounts of polycarbonate. During the thermal oxidative aging process, the polycarbonate underwent Fries rearrangement due to the combined action of heat and oxygen, increasing the content of crosslinked structures. As a result, the tensile strength retention rate after aging was higher than 100%. Through comprehensive control of each component, Example 1 achieved the highest tensile strength retention rate after aging and the smallest color difference. Both Examples 4 and 5 had smaller color differences than Examples 2 and 3, demonstrating a more significant improvement in the browning problem (smaller color differences).

[0060] Examples 1 and 7 to 9 show that when the average molecular weight of the polycarbonate is in the appropriate range (21,000 to 33,650), the compatibility between the toughener and the matrix resin is further improved, the tensile strength retention rate of the polycarbonate alloy material after aging is higher, and the browning problem is more significantly improved (the color difference is smaller).

[0061] From Examples 1 and 10, it was found that the acrylonitrile-butadiene-styrene copolymer synthesized by the bulk polymerization method had a more appropriate rubber content, better compatibility with the toughener, and a more stable structure formed by the toughener and matrix resin, and therefore the resulting polycarbonate alloy material had a higher tensile strength retention rate after aging and a more significant improvement in the browning problem (smaller color difference).

[0062] From Examples 1 and 11, it was found that the use of a specific phosphorus-based flame retardant resulted in a higher tensile strength retention rate after aging of the resulting polycarbonate alloy material, and a more significant improvement in the browning problem (smaller color difference).

[0063] From Examples 1 and 12 to 16, it was found that when the ratio of shell thickness to core diameter was 1:(6 to 30) and the shell was made of acrylate (Examples 1, 13, 14 and 15), the tensile strength retention rate of the polycarbonate alloy material after aging was higher and the improvement in the browning problem was more significant (the color difference was small).

[0064] From Examples 1, 12, 13, and 15, it was found that when the ratio of shell thickness to core diameter was 1:(6-30) and the silicon content of the toughener with a core-shell structure was 30-80 wt% (Examples 1, 13, and 15), the tensile strength retention rate of the polycarbonate alloy material after aging was higher.

[0065] From Examples 1, 17 to 21, it was found that when the composite stabilizer was used (Examples 1, 17, and 18), the tensile strength retention rate of the polycarbonate alloy material after aging was higher and the improvement in the browning problem was more significant (the color difference was small).

[0066] In Comparative Example 1, the shell thickness to core diameter ratio of the added toughener was too high, resulting in a significant decrease in the tensile strength of the polycarbonate alloy material after long-term thermal oxidative aging (retention rate less than 50%). In Comparative Example 2, the silicon content of the added toughener was too high, resulting in a significant decrease in the tensile strength of the polycarbonate alloy material after long-term thermal oxidative aging (retention rate less than 50%) and insufficient improvement in the browning problem (color difference greater than 5). In Comparative Examples 3 and 4, the added toughener was inappropriate, resulting in a significant decrease in the tensile strength of the polycarbonate alloy material after long-term thermal oxidative aging (retention rate less than 50%) and insufficient improvement in the browning problem (color difference greater than 5). In Comparative Example 5, no toughener was added, resulting in a significant decrease in the tensile strength of the polycarbonate alloy material after long-term thermal oxidative aging (retention rate less than 50%) and insufficient improvement in the browning problem (color difference greater than 5).

[0067] It is clear that the above examples of the present invention are merely examples for clearly explaining the present invention and do not limit the embodiments of the present invention. Those skilled in the art can make other different changes or modifications based on the above description. It is not necessary to restrictively list all embodiments here, and it is not possible to list all embodiments. Any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A polycarbonate alloy material having good color stability, comprising: 50 to 90 parts by weight of polycarbonate; 1 to 20 parts by weight of an acrylonitrile-butadiene-styrene copolymer; 5 to 20 parts by weight of a flame retardant; 1 to 25 parts by weight of a toughener; 0.1 to 2 parts by weight of a stabilizer; 0.1 to 5 parts by weight of an anti-dripping agent; The toughener has a core-shell structure, the ratio of the shell thickness to the core diameter of the toughener is 1:(5-30), the core of the toughener is silicone rubber, and the silicone content of the toughener is 8-80 wt %.

2. The polycarbonate alloy material contains, as components: 60 to 85 parts by weight of polycarbonate; 3 to 10 parts by weight of an acrylonitrile-butadiene-styrene copolymer; 7 to 10 parts by weight of a flame retardant; 3 to 10 parts by weight of a toughener; 0.25 to 1.2 parts by weight of a stabilizer; The polycarbonate alloy material according to claim 1, further comprising 0.3 to 0.8 parts by weight of an anti-dripping agent.

3. 2. The polycarbonate alloy material according to claim 1, wherein the ratio of the shell thickness to the core diameter of the toughener having a core-shell structure is 1:(6-30).

4. 2. The polycarbonate alloy material according to claim 1, wherein the silicon content of the toughener having a core-shell structure is 30 to 80 wt %.

5. 2. The polycarbonate alloy material according to claim 1, wherein the flame retardant is a phosphorus-based flame retardant.

6. 2. The polycarbonate alloy material according to claim 1, wherein the acrylonitrile-butadiene-styrene copolymer is obtained by bulk polymerization.

7. 2. The polycarbonate alloy material according to claim 1, wherein the polycarbonate has an average molecular weight of 21,000 to 33,650.

8. The polycarbonate alloy material according to claim 1, characterized in that the stabilizer consists of a metal deactivator, a hindered phenolic antioxidant, and a glycidyl methacrylate-grafted styrene-acrylonitrile copolymer in a mass ratio of 1:(1-3):(1-8).

9. 9. A method for preparing a polycarbonate alloy material according to claim 1, comprising the steps of mixing, melting, extruding and granulating each component to obtain the polycarbonate alloy material.

10. Use of the polycarbonate alloy material according to any one of claims 1 to 8 in the manufacture of photovoltaic products.

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