GPPS composite material and preparation method and application thereof

Abstract

This application discloses a GPPS composite material, its preparation method, and its application, relating to the field of polymer materials technology. This application provides a GPPS composite material comprising the following components in parts by weight: 70-95 parts GPPS resin (general-purpose polystyrene), 5-25 parts polyvinylpyrrolidone, and 0.1-0.5 parts inorganic mineral powder; wherein the particle size D50 of the inorganic mineral powder is 380-490 nm. This application yields a GPPS composite material that can reduce the blue light transmittance in LED lights without affecting luminous efficacy.

Description

Technical Field

[0001] This application relates to the field of polymer materials technology, and in particular to a GPPS composite material, its preparation method and application. Background Technology

[0002] With the improvement of LED light source luminous efficiency, LED lighting products are receiving increasing attention from governments and enterprises in developed countries. Their application and popularization are constantly expanding. As a new generation of "green lighting products", LED lighting products are gradually gaining popularity. Their high efficiency, energy saving, environmental protection and long lifespan are particularly prominent in functional lighting applications such as road lighting, tunnel lighting and public lighting.

[0003] LEDs are strong point light sources. When used in lighting products, their light intensity often needs to be homogenized to eliminate glare. The most common practice is to add a transparent diffuser to the outside of the LED light source to homogenize the light. The scattering effect of the transparent diffuser on the LED light is generally achieved by adding a certain proportion of light diffusing agent or by structuring the surface of the lampshade (such as the commonly used frosted finish, prism structure, etc.). Homogenizing the LED light by adding light diffusing agent often results in a decrease in luminous efficacy. Homogenizing the LED light by surface structuring has certain requirements for the product molding method and the equipment cost is relatively high. In addition, due to the influence of LED light-emitting mechanism, the white light produced by LEDs often contains a certain proportion of blue light (420-460nm). A high proportion of blue light can inhibit melatonin secretion, interfere with sleep rhythm, and long-term high-intensity exposure to blue light may also lead to the potential risk of photochemical damage to the retina. The common practices are as follows: 1) Optimization with phosphor technology (using specially formulated phosphors to broaden the emission spectrum and reduce the blue light peak); 2) violet light chip + RGB phosphor (using violet light chip to excite multiple RGB phosphors, completely avoiding the blue light chip); 3) quantum dot technology (using quantum dot materials to convert part of the blue light); 4) micro-filtering technology (adding a filter layer to the surface of the LED package to selectively absorb high-energy blue light); 5) dynamically reducing the intensity of blue light or changing the driving method through circuit design.

[0004] The above methods often lead to increased costs and even decreased luminous efficacy. Therefore, a GPPS composite material that can reduce the blue light transmittance in LED lights without affecting luminous efficacy has broad application prospects. Summary of the Invention

[0005] Based on this, the purpose of this application is to overcome the shortcomings of the prior art and provide a GPPS composite material, its preparation method and application.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: a GPPS composite material comprising the following components in parts by weight: 70-95 parts of GPPS resin (general-purpose polystyrene), 5-25 parts of polyvinylpyrrolidone (PVP), and 0.1-0.5 parts of inorganic mineral powder; wherein the particle size D50 of the inorganic mineral powder is 380-490 nm.

[0007] This application reduces the blue light transmittance of LED lights by adding an appropriate amount of polyvinylpyrrolidone (PVP) to GPPS resin, along with inorganic mineral powder of a specific particle size. This is achieved without requiring additional diffusing agents or microstructural treatment of the mold, and without affecting luminous efficacy. The result is a change from cool white light to warm yellow light from the LED light passing through the lampshade. PVP and GPPS resin have poor compatibility, and their composite system is prone to phase separation, forming a heterogeneous structure with a size of 420-460 nm. This heterogeneous structure selectively reflects and scatters blue light, reducing the blue light transmittance of LED lights. The inorganic mineral powder of this application, with a particle size comparable to the wavelength of blue light, blocks and scatters the blue light emitted by the LED, further reducing its transmittance.

[0008] As an embodiment of this application, based on the total weight of the GPPS composite material, the weight percentage of the GPPS resin is not less than 70%; the weight percentage of the polyvinylpyrrolidone is not less than 5%, such as 5-25%; and the weight percentage of the inorganic mineral powder is not less than 0.05%, such as 0.05-0.6%.

[0009] The particle size D50 of the inorganic mineral powder was tested using a laser method, as follows: 3g of filler was added to 500mL of water and shaken in an ultrasonic instrument for 1min. The well-dispersed sample was then added and placed in a Malvern laser particle size analyzer for testing. The laser wavelength was 630nm, the scattering angle was 90°, the test time was 300s, the correlator was set to low speed, the medium temperature was 21°C, the light intensity distribution type was selected, and the CONTIN2 analysis mode was used.

[0010] In one embodiment, the GPPS resin has a weight range of 70 parts, 75 parts, 78 parts, 80 parts, 85 parts, 88 parts, 90 parts, and 95 parts, or any two of these values; the polyvinylpyrrolidone has a weight range of 5 parts, 8 parts, 10 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 20 parts, and 25 parts, or any two of these values; and the inorganic mineral powder has a weight range of 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, and 0.5 parts, or any two of these values.

[0011] In one embodiment, the particle size D50 of the inorganic mineral powder is a range of one or any two of 380nm, 400nm, 420nm, 450nm, 480nm, and 490nm.

[0012] In one embodiment, the particle size D50 of the inorganic mineral powder is 410-460 nm.

[0013] As an embodiment of this application, the GPPS composite material comprises the following components in parts by weight: 80-90 parts of GPPS resin, 10-20 parts of polyvinylpyrrolidone, and 0.2-0.4 parts of inorganic mineral powder.

[0014] As an embodiment of this application, the K value of the polyvinylpyrrolidone is 25-100; in one embodiment, the K value of the polyvinylpyrrolidone is 40-50.

[0015] In one embodiment, the K value of the polyvinylpyrrolidone is a range of one or both of the following: 25, 30, 40, 45, 50, 60, 65, 70, 80, 85, 90, 100.

[0016] It should be noted that the K value of polyvinylpyrrolidone refers to a characteristic value related to the relative viscosity of polyvinylpyrrolidone. The relative viscosity of a polymer is a physical quantity related to the molecular weight of the polymer. Therefore, the K value of polyvinylpyrrolidone can be used to characterize the average molecular weight of polyvinylpyrrolidone. The larger the K value, the larger the molecular weight. In this invention, the K value of the above-mentioned polyvinylpyrrolidone can be tested with reference to "GB / T 33069-2016 Test Method for Industrial Poly-N-Vinylpyrrolidone".

[0017] As an embodiment of this application, the GPPS resin has a melt flow rate of 1-12 g / 10 min at 200°C / 5 kg according to ISO 1133-2011.

[0018] In one embodiment, the GPPS resin has a melt flow rate of 1 g / 10 min, 2 g / 10 min, 4 g / 10 min, 5 g / 10 min, 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, or 12 g / 10 min, according to ISO 1133-2011 at 200 °C / 5 kg, or any combination thereof.

[0019] As an embodiment of this application, the inorganic mineral powder is at least one of talc, mica, wollastonite, calcium carbonate, and barium sulfate.

[0020] As an embodiment of this application, the GPPS composite material further includes 0-5 parts of processing aids, wherein the aids are at least one of antioxidants and lubricants; for example, 0.2-2 parts of antioxidants and 0.3-3 parts of lubricants.

[0021] As an embodiment of this application, the antioxidant is at least one of hindered phenolic antioxidants, hindered amine antioxidants, and phosphite antioxidants. Specifically, the antioxidant includes, but is not limited to, at least one of N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexamethylenediamine (antioxidant 1098), tris[2,4-di-tert-butylphenyl]phosphite (antioxidant 168), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (antioxidant 1010), and phosphite antioxidants.

[0022] As an embodiment of this application, the lubricant is at least one of amides, polysiloxanes, stearates, stearic acid, and organosilicones; such as vinyl bis-stearamide, pentaerythritol stearate, zinc stearate, etc.

[0023] Furthermore, this application provides a method for preparing the aforementioned GPPS composite material, comprising the following steps: (1) Weigh each component according to its weight parts; (2) The above components are mixed and added to an extruder for melt dispersion, melt kneading, extrusion granulation, and the GPPS composite material is obtained.

[0024] As an embodiment of this application, the extruder is a twin-screw extruder.

[0025] As an implementation scheme of this application, the temperatures of each working zone in the twin-screw extruder are as follows: the temperatures of zones one and two are each 120-180℃, the temperatures of zones three to five are each 190-230℃, and the temperatures of zones six to ten are each 190-210℃.

[0026] As an embodiment of this application, the twin-screw extruder has a screw length-to-diameter ratio of 36:1-48:1 and a screw speed of 400-450 rpm.

[0027] Furthermore, this application provides the application of the GPPS composite material in lighting and display equipment; specifically, the GPPS composite material is used to manufacture LED lampshades, advertising billboards, or displays.

[0028] Furthermore, this application provides a component formed from the aforementioned GPPS composite material, wherein the forming method includes, but is not limited to, injection molding, blow molding, vacuum forming, and extrusion.

[0029] Compared to existing technologies, the advantages of this application are as follows: By adding an appropriate amount of polyvinylpyrrolidone (PVP) to GPPS resin, combined with inorganic mineral powder of a specific particle size, this application can reduce the blue light transmittance of LED lights without affecting luminous efficacy, without the need for additional diffusing agents or microstructural treatment of the mold. This changes the LED light passing through the lampshade from cool white light to warm yellow light. PVP and GPPS resin have poor compatibility, and the PVP and GPPS resin composite system is prone to phase separation, forming a heterogeneous structure with a scale of 420-460 nm. This heterogeneous structure selectively reflects and scatters blue light, reducing the blue light transmittance of LED lights. The inorganic mineral powder of a specific particle size in this application, with a particle size comparable to the blue light wavelength, blocks and scatters the blue light emitted by the LED light, further reducing the blue light transmittance. Detailed Implementation

[0030] To better illustrate the purpose, technical solution, and advantages of this application, the following detailed description, in conjunction with specific embodiments, will further illustrate the application. The purpose is to provide a detailed understanding of the content of this application, not to limit it. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application. Unless otherwise specified, the experimental reagents and instruments designed in the embodiments and comparative examples of this application are commonly used and commercially available. Unless otherwise specified, the experimental methods used in the embodiments and comparative examples are conventional methods; and unless otherwise specified, the raw materials used in parallel experiments are from the same batch.

[0031] The raw materials used in the embodiments and comparative examples are described below, but are not limited to these materials: GPPS Resin-1: Melt flow rate of 1.6 g / 10 min (200℃ / 5 kg), GPPS 351P, Shanghai SECCO; GPPS Resin-2: Melt flow rate of 8 g / 10 min (200℃ / 5 kg), GPPS 123P, Shanghai SECCO; GPPS Resin-3: Melt flow rate of 9 / 10 min (200℃ / 5kg), GPPS 525B, Total, France; PVP-1: K value 30, purchased from Shanghai Kema; PVP-2: K value 40, purchased from Shanghai Kema; PVP-3: K value 50, purchased from Shanghai Kema; PVP-4: K value 80, purchased from Shanghai Kema; PVP-5: K value 100, purchased from Shanghai Kema; Calcium carbonate-1: Particle size D50 390nm; Calcium carbonate-2: Particle size D50 420nm; Calcium carbonate-3: Particle size D50 450nm; Calcium carbonate-4: Particle size D50 480nm; Calcium carbonate-5: Particle size D50 0.7μm, grade MP-RI, manufacturer: Guangxi Huana New Materials; Calcium carbonate-6: Particle size D50 110nm; Talc: Particle size D50 390nm; Among them, Guangxi Huana New Materials MP-RI (particle size 0.7um) or HTPULTRA5L (particle size 2.5um) was used as the masterbatch, and calcium carbonate with different particle sizes D50 was ground by wet grinding process.

[0032] The antioxidant is a complex of commercially available hindered phenolic antioxidant 1010 and commercially available phosphite antioxidant 168 in a mass ratio of 1:1.

[0033] Lubricant: Vinyl bis-stearamide, commercially available.

[0034] PMMA resin: melt index of 2 g / 10 min (230℃ / 3.8 kg), purchased from Chi Mei Chemical, grade CM-205; Examples and Comparative Examples This application provides a method for preparing the aforementioned GPPS composite material, comprising the following steps: (1) Weigh each component according to its weight parts; (2) The above components are mixed and added to a twin-screw extruder for melt dispersion, melt kneading, extrusion granulation, and the GPPS composite material is obtained; The twin-screw extruder is divided into ten zones, with the following temperatures: zones one and two are both 150℃, zones three through five are both 200℃, and zones six through ten are both 200℃. The twin-screw extruder has a screw length-to-diameter ratio of 40:1 and a screw speed of 400 rpm.

[0035] Performance testing (1) Luminous efficacy test: After drying, the GPPS composite material prepared in the examples and comparative examples was injection molded into a square plate with a thickness of 2.0 mm, a length of 150 mm and a width of 150 mm. The plate was placed under an LED light group and the brightness was tested using an EVERFINE photometer. The higher the brightness, the stronger the luminous efficacy. The current was fixed at 174 mA and the voltage was fixed at 8.3 V. (2) Blue light transmittance evaluation: The GPPS composite material prepared in the examples and comparative examples was dried and injection molded into a square plate with a thickness of 2.0 mm, a length of 150 mm and a width of 150 mm. It was placed under an LED light group and the color temperature was tested using an EVERFINE photometer. The lower the color temperature, the lower the blue light transmittance. The current was fixed at 174 mA and the voltage was fixed at 8.3 V.

[0036] Table 1 Table 2 As shown in the table above, the GPPS composite material prepared in the examples has a brightness ≥750 cd / m² and a color temperature ≤6500K, which can reduce blue light transmittance without affecting light efficiency.

[0037] As can be seen from the comparison of Examples 1-3, the GPPS resin, according to ISO 1133-2011, can reduce blue light transmittance at a melt flow rate of 1-12 g / 10 min at 200℃ / 5 kg without affecting the light efficiency.

[0038] As can be seen from the comparison of Examples 1 and 4-7, the K value of polyvinylpyrrolidone affects the final effect. When the K value of polyvinylpyrrolidone is 40-50, the matching between GPPS and polyvinylpyrrolidone is better. When the resin system separates phases, it can form a heterogeneous structure with a specific size distribution, which can reduce the blue light transmittance without affecting the light efficiency.

[0039] As can be seen from the comparison of Examples 1, 8-11, and Comparative Examples 2-3, the particle size of the inorganic mineral powder affects the final effect. When the particle size D50 of the inorganic mineral powder is 380-490 nm, the particle size is comparable to the wavelength of blue light, thus blocking and scattering blue light, further reducing the transmittance of blue light. When the particle size D50 is 410-460 nm, the particle size is closer to the wavelength of blue light, resulting in a better effect in reducing the transmittance of blue light. When the particle size of the inorganic mineral powder is too large, it blocks the entire visible light band, preventing light from passing through. When the particle size of the inorganic mineral powder is too small, it is difficult to effectively scatter or reflect the blue light band, resulting in high blue light transmittance.

[0040] As can be seen from the comparison of Example 1 and Comparative Example 1, polyvinylpyrrolidone and PMMA have good compatibility and will not undergo phase separation. They cannot form heterogeneous structures of a specific size, thus reducing the reflection and scattering of specific wavelengths and resulting in high blue light transmittance.

[0041] As can be seen from the comparison between Example 1 and Comparative Example 4, when the system does not contain inorganic mineral powder, it cannot further block and scatter blue light, resulting in high blue light transmittance. As can be seen from the comparison between Example 1 and Comparative Example 5, when calcium carbonate is in excess, the blue light transmittance is low, but the calcium carbonate forms a barrier, resulting in poor light efficiency.

[0042] As can be seen from the comparison of Example 1 and Comparative Examples 6-7, when the amount of polyvinylpyrrolidone is too low, a heterogeneous structure with a specific size distribution cannot be formed, resulting in high blue light transmittance. When the amount of polyvinylpyrrolidone is too high, the size of the heterogeneous structure will increase, blocking the passage of the entire visible light band and affecting normal use.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit the scope of protection of this application. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the substance and scope of the technical solutions of this application.

Claims

1. A GPPS composite material, characterized in that, It comprises the following components in parts by weight: 70-95 parts GPPS resin, 5-25 parts polyvinylpyrrolidone, and 0.1-0.5 parts inorganic mineral powder; wherein the particle size D50 of the inorganic mineral powder is 380-490 nm.

2. The GPPS composite material as described in claim 1, characterized in that, It includes the following components in parts by weight: 80-90 parts GPPS resin, 10-20 parts polyvinylpyrrolidone, and 0.2-0.4 parts inorganic mineral powder.

3. The GPPS composite material as described in claim 1, characterized in that, The K value of the polyvinylpyrrolidone is 25-100; preferably, the K value of the polyvinylpyrrolidone is 40-50.

4. The GPPS composite material as described in claim 1, characterized in that, The GPPS resin has a melt flow rate of 1-12 g / 10 min at 200°C / 5 kg according to ISO 1133-2011.

5. The GPPS composite material as described in claim 1, characterized in that, The inorganic mineral powder is at least one of talc, mica, wollastonite, calcium carbonate, and barium sulfate; the particle size D50 of the inorganic mineral powder is 410-460 nm.

6. The GPPS composite material as described in claim 1, characterized in that, It also includes 0-5 parts of processing aids, wherein the aids are at least one of antioxidants and lubricants.

7. A method for preparing the GPPS composite material according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Weigh each component according to its weight parts; (2) The above components are mixed and added to an extruder for melt dispersion, melt kneading, extrusion granulation, and the GPPS composite material is obtained.

8. The application of a GPPS composite material as described in any one of claims 1-6 in lighting and display equipment.

9. The application as described in claim 8, characterized in that, The GPPS composite material is used to manufacture LED lampshades, advertising billboards, or displays.

10. An article formed from a GPPS composite material comprising any one of claims 1-6.

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