A high heat-resistant, infrared-transmitting, spray-free PMMA / PC material and its preparation and application

Abstract

This invention discloses a high heat-resistant, infrared-transmitting, paint-free PMMA / PC material and its preparation and application. The material is prepared by melting and mixing raw materials including PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigments to obtain the high heat-resistant, infrared-transmitting, paint-free PMMA / PC material. Currently, black infrared-transmitting plastic materials are mainly PMMA, but they do not possess the surface quality required for paint-free application. Furthermore, black paint-free PMMA has difficulty transmitting infrared light. Improving the light transmittance of black materials, especially infrared light transmittance, can significantly expand the application range of materials, particularly since existing high-gloss black paint-free sheets are invisible. This invention employs a new technical formulation, selecting PMMA and PC, combined with additives and colorants, unexpectedly achieving excellent infrared transmittance and a high-gloss black paint-free finish. It also possesses good heat resistance and toughness. Furthermore, the product of this invention, after injection molding, has a visible effect, allowing the object behind the sheet to be clearly seen.

Description

Technical Field

[0001] This invention belongs to the field of new materials technology and relates to a modified PMMA / PC material, specifically a high heat-resistant, infrared-transmitting, paint-free PMMA / PC material, its preparation, and its application in electronic and optical instruments. Background Technology

[0002] High-transmittance infrared materials have numerous applications in electronic materials, high-frequency materials, and electromagnetic shielding materials, such as infrared windows and optical detectors. For example, dashcam lenses include coating a layer of infrared-transmitting ink in a predetermined infrared-transmitting area to form an infrared-transmitting zone. Traditional transparent materials, such as indium tin oxide (ITO), have low infrared transmittance and suffer from high brittleness and poor flexibility. Existing technology discloses an infrared transparent broadband electromagnetic shielding material. By selecting a substrate with high infrared transmittance, using an infrared transparent polymer as an adhesion-enhancing layer, and optimizing the metal mesh design, the material achieves high transmittance in the 2-20μm infrared band. However, its manufacturing process is overly complex and the raw material cost is high, which limits the industrial application of this product. PMMA possesses good infrared transmittance, but its inherently low thermal performance necessitates improvement. Furthermore, existing paint-free (black) PMMA materials lack good infrared transmittance. The applicant previously disclosed a modified heat-resistant PMMA, achieved by melting and mixing PMMA resin, modifying materials, and additives, primarily addressing the insufficient heat resistance issue. While achieving a high-gloss black appearance, its infrared transmittance is poor. Currently, high-gloss black materials mainly prioritize blackness, gloss, scratch resistance, weather resistance, and heat resistance, neglecting visibility. This is particularly true in industries like automotive, where high-gloss black is the mainstream color, leading to high demand for paint-free high-gloss black PC products. Consequently, there is a lack of visible, paint-free high-gloss black materials. Therefore, it is necessary to develop new modified materials that possess good infrared transmittance and visual visibility, along with a high-gloss black paint-free appearance and good heat resistance. Summary of the Invention

[0003] Infrared translucent materials are mainly used in consumer electronics, automotive electronics, industry, and medical fields, such as infrared sensors, infrared cameras, infrared radar, and infrared remote controls. They also have important applications in automobiles, such as vehicle recognition panels and indicator light panels. Currently, black infrared-translucent plastic materials are mainly PMMA, but they do not possess the surface quality required for coating-free application. Moreover, black coating-free PMMA has difficulty transmitting infrared light. Improving the light transmittance of black materials, especially infrared light transmittance, can significantly expand the application range of materials, especially since existing high-gloss black coating-free sheets are invisible. This invention uses a new technical formula, selecting PMMA and PC, combined with additives and colorants, to unexpectedly achieve good infrared transmittance and a high-gloss black coating-free effect, while also possessing good heat resistance and toughness. Furthermore, the product of this invention has a visible effect after injection molding.

[0004] The present invention adopts the following technical solution.

[0005] A high heat-resistant, infrared-transmitting, spray-free PMMA / PC material is prepared from PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigment, wherein the pigment is oil-based black.

[0006] In this invention, the raw materials for preparing PC include dimethyl carbonate and alcohol. The polycarbonate is used as a heat-resistant modifier to modify the heat resistance of PMMA, increase the Vicat softening point temperature of PMMA material, and together with PMMA, it serves as the main resin, providing a basis for good infrared transmittance and visibility.

[0007] In this invention, oil-based black can provide a glossy black finish. Unexpectedly, when combined with resin and additives, it achieves good infrared transmittance, especially achieving the technical effects of no-spraying and visible visibility.

[0008] In this invention, the combined use of silicone oil and polyester-modified silicone ensures the scratch resistance of the material. Compared with scratch-resistant agents such as silicone abrasion-resistant powder and silica, the scratch-resistant agent of this invention does not affect the infrared transmittance and visual visibility while ensuring scratch resistance.

[0009] Preferably, the present invention uses a small amount of polyester-modified silicone combined with a large amount of silicone oil as an additive for PMMA and PC main resins, which ensures the performance of the oil-blackening effect, achieves good dispersion performance of each component, reduces light scattering inside the substrate, provides a foundation for high black gloss, and has a visible effect. Crucially, it meets the basic requirements of wear resistance and scratch resistance for infrared transmission and no-spray coating.

[0010] In this invention, the additives include commonly used antioxidants, UV stabilizers, etc.

[0011] This invention discloses a method for preparing the above-mentioned high heat-resistant infrared-transmitting paint-free PMMA / PC material. The method involves melting and mixing raw materials including PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigments to obtain the high heat-resistant infrared-transmitting paint-free PMMA / PC material. This material has a paint-free appearance and can replace painted plastics.

[0012] In this invention, an extruder is used to achieve melt mixing, which is a conventional technique. The inventiveness of this invention lies in the disclosure of a new formula, which selects PMMA and PC, adds oil-based black pigment, and co-extrudes and granulates with conventional additives in the presence of polyester-modified silicone and silicone oil additives. The resulting material has a paint-free appearance after injection molding and good infrared transmittance, making it suitable for automotive parts.

[0013] This invention involves the melt-mixing of PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigments to obtain a high-heat-resistant, infrared-transmitting, paint-free PMMA / PC material. The materials used in this invention can be directly fed into a twin-screw extruder for melt processing, or individual materials can be added to the extruder separately using a loss-in-weight weighing scale. Processing additives and oil-based black materials are mixed together and added using a separate loss-in-weight weighing scale, ensuring a feeding accuracy within 0.5%. The twin-screw extruder used can have a diameter of 30-75 mm, a rotation speed of 100-250 rpm, and a processing temperature of 200-270℃ for granulation.

[0014] Preferably, polyester-modified silicone and oil-based black are first mixed at 55-65℃, preferably 60℃, to obtain polyester-modified silicone composite oil-based black, which is then conventionally mixed with PMMA, PC, silicone oil, and additives before feeding and extrusion to obtain a high heat-resistant, infrared-transmitting, paint-free PMMA / PC material.

[0015] In this invention, the mass ratio of PMMA to PC is (60-80):(20-40), preferably (60-70):(30-40).

[0016] In this invention, the mass of PMMA and PC is 100%, the mass of polyester modified silicone is 0.1%-0.5%, the mass of silicone oil is 1%-1.7%, the mass of additives is 0.2%-0.6%, and the mass of pigment is 0.1%-0.3%, preferably greater than 0.1%.

[0017] Preferably, the mass of PMMA and PC is 100%, the mass of polyester modified silicone is 0.2%-0.4%, the mass of silicone oil is 1.2%-1.5%, the mass of additives is 0.3%-0.5%, and the mass of pigment is 0.15%-0.25%.

[0018] This invention discloses the application of the above-mentioned high heat-resistant infrared-transmitting, paint-free PMMA / PC material in the preparation of black infrared-transmitting materials.

[0019] This invention discloses the application of the above-mentioned high heat-resistant infrared-transmitting, spray-free PMMA / PC material in the preparation of visible black infrared-transmitting materials.

[0020] This invention discloses the application of the above-mentioned high heat-resistant infrared-transmitting, spray-free PMMA / PC material in the preparation of visible, high-brightness, black infrared-transmitting materials.

[0021] This invention discloses the application of the above-mentioned high heat-resistant infrared-transmitting PMMA / PC material without spraying in the preparation of visible high-gloss black infrared-transmitting material without spraying.

[0022] A functional material is prepared from the aforementioned high heat-resistant, infrared-transmitting, paint-free PMMA / PC material. Furthermore, this functional material, prepared from the aforementioned high heat-resistant, infrared-transmitting, paint-free PMMA / PC material, possesses the functions of being visible, high-gloss black, paint-free, and infrared-transmitting.

[0023] For materials that do not require painting and only need to be black, infrared transmission can be achieved through the use of pigments. However, the addition of black pigments will affect the melt extrusion and injection molding of polymethyl methacrylate / polycarbonate, resulting in defects such as blooming, flow marks, fogging, silver streaks, and white spots on the surface of the product. This is not suitable for automotive parts with high requirements for black gloss and is prone to high scrap rate.

[0024] Existing technologies have successfully prepared high-gloss, paint-free plastics through the combination of pigments, resins, and additives, and some products are already commercially available. The applicant has previously disclosed various related materials, such as ultra-heat-resistant, high-impact PMMA+ASA paint-free materials and high-gloss PMMA / PC / ASA composite materials. These materials have low L-values, but are invisible to the naked eye, making it impossible to see objects behind the sheet, and are also difficult to transmit infrared light. This invention solves this problem. It still uses PMMA and PC, which have excellent heat resistance, as the base resins. By using oil-based black pigments combined with polyester-modified silicone and silicone oil, the dispersion effect of each raw material is ensured, light scattering within the substrate is reduced, and powder aggregation and surface haze are avoided. Without changing the screw extrusion process, a high-heat-resistant, infrared-transmitting paint-free PMMA / PC material is obtained. Injection-molded sheet testing shows that it meets basic mechanical and scratch resistance requirements. After infrared irradiation, the infrared light spots transmitted through the sheet are clearly visible, and objects behind the sheet can be seen with the naked eye. Moreover, the tested L-value (SCE) is less than 1, making it suitable for automotive identification panels, indicator light panels, etc. Attached Figure Description

[0025] Figure 1 The images show the high heat-resistant, infrared-transmitting, paint-free PMMA / PC material of this invention and a comparative material.

[0026] Figure 2This is a photograph of the high heat-resistant, infrared-transmitting, paint-free PMMA / PC material of this invention, showing its infrared transmission.

[0027] Figure 3 These are photos of the visible and infrared transmittance tests of commercially available high-gloss black materials.

[0028] Figure 4 This is a photograph of the infrared-transmitting PMMA / PC material of the present invention, which is highly heat-resistant and infrared-transmitting without the need for spraying. Detailed Implementation

[0029] While existing technologies contain infrared-transmitting black materials, there are no reports of paint-free black materials that are also infrared-transmitting. In particular, existing high-gloss, paint-free high-black products are invisible to the naked eye, making it impossible to see objects behind the material. For example, CN114426730A discloses a high-gloss black paint-free polypropylene composite and its preparation method, which is invisible. This invention, targeting specific applications such as automotive identification panels and indicator light panels, discloses for the first time a high-heat-resistant, infrared-transmitting, paint-free PMMA / PC material that, while maintaining a high-gloss black paint-free effect, effectively transmits infrared light, allowing objects behind the material to be seen with the naked eye.

[0030] This invention involves mixing polyester-modified silicone and oil-based black at 55-65℃, preferably 60℃, to obtain polyester-modified silicone composite oil-based black. This is then conventionally mixed with PMMA, PC, silicone oil, and additives before feeding and extrusion to obtain a high-heat-resistant, infrared-transmitting, paint-free PMMA / PC material, ensuring a feeding accuracy of less than 0.5%. The twin-screw extruder used can have a diameter of 30-75mm, a rotation speed of 100-250rpm, and a processing and granulation temperature of 200-270℃.

[0031] This invention uses PMMA / PC as the base resin to provide a foundation for heat resistance. It is supplemented with oil-based black pigment to solve the problem that conventional black pigment products with high gloss have difficulty transmitting infrared light. At the same time, it incorporates a polyester-modified silicone / silicone oil composite system to maintain basic scratch resistance and impact resistance, enabling basic use in automotive identification panels, indicator light panels, and other components. Moreover, the resin material has low internal scattering and good dispersion of pigments and additives, which is beneficial for improving high gloss and visibility.

[0032] This invention, through the synergistic design of PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigments, achieves a high-gloss black effect in a single injection molding process. This not only reduces emissions from the painting process but also avoids the risk of coating aging and failure. The injection-molded parts maintain good appearance and mechanical properties after long-term use, improving the practicality of the material. The following specific experiments illustrate the technological advancements of this invention. The raw materials used are existing products that meet the conventional requirements for automotive parts. The specific preparation operations and performance testing utilize conventional techniques.

[0033] This invention selects polycarbonate as a modifier to reduce dependence on petroleum, lower costs compared to paint materials, and meets the performance requirements of development and design. It is suitable for application in high-requirement parts, and the project is ready for mass production. Specifically, the PC used is Copt HC-81T-R, which is produced by melt condensation polymerization of isosorbide (ISB), 1,4-cyclohexanediethanol (CHDM), and dimethyl carbonate (DMC). This polycarbonate is the modifier selected in this invention for modifying the heat and weather resistance of PMMA, improving the performance of PMMA materials. Furthermore, the amount of PC used in this invention is lower than that of PMMA to meet the requirements for heat and weather resistance.

[0034] General preparation method: Polyester-modified silicone and oil-based black are first mixed at 60°C for 20 minutes to obtain polyester-modified silicone composite oil-based black, which is used for the next step of premixing; if the experimental formulation does not contain polyester-modified silicone, this step is omitted. The weighed raw materials are placed in a high-speed batching mixer and mixed evenly at room temperature to obtain a premix. This premix is ​​then fed into a twin-screw extruder via a metering device. Under the conveying, shearing, and mixing action of the screws, the material melts and composites. After extrusion, stranding, cooling, and pelletizing, a high-heat-resistant, infrared-transmitting, paint-free PMMA / PC material is obtained. The extrusion process is as follows: Twin-screw extruder temperature zones: Section 1: 200℃, Section 2: 210℃, Section 3: 220℃, Section 4: 230℃, Section 5: 240℃, Section 6: 250℃, Section 7: 240℃, Section 8: 250℃, Section 9: 260℃, Section 10: 260℃, Die Head: 270℃, Rotation Speed: 250 rpm. The extruded material is then cooled and granulated to obtain the corresponding product.

[0035] Material description: PMMA Resin 1: This PMMA resin has a Vicat softening temperature of 105℃, a light transmittance of 92%, and a melt index of 1.0-3.2g / 10min (230℃*3.8kg). It is Chimei CM205. PMMA Resin 2: This PMMA resin has a Vicat softening temperature of 96℃, a light transmittance of 92%, and a melt index of 13-18 g / 10min (230℃*3.8kg). It is Chimei CM211. PC resin 1, Lotte 1220 from South Korea; PC Resin 2: Copt HC-81T-R; PC resin 3: Cangzhou Dahua CH9115LT; Gas-phase nano SO2: Huifu Nanomaterials, HB-132, D90 particle size 30nm; Polyester-modified silicone: H-Si 6441P; Silicone oil: Shin-Etsu Chemical, Japan, KF-54; Additives: Commonly used combination of antioxidants and UV stabilizers, specifically antioxidants: 1010 and 168 in a mass ratio of 1:1; UV stabilizer: TINUVIN 770, in equal amounts to the antioxidants; Pigment 1: Kunshan Caizhiyuan, Plastic Black HR; Pigment 2: Daxing, Oil Black MF045-6; Pigment 3: Xingtai Guang, TA-7002D.

[0036] The testing methods and sample preparation for the materials are standard techniques, briefly described below: Vicat softening temperature: Tested according to ISO 306, B50 method, heating rate 50℃ / h, requirement ≥110℃; Appearance color: Under normal temperature conditions (23±2℃), a colorimeter is used to test the injection-molded samples from the same mold. The L value is required to be ≤1.5 (visually achieving a high-gloss black paint effect). Simply supported beam impact test (at room temperature): At room temperature (23±℃), the required value according to standard ISO 179-1eU is ≥25kJ / m. 2 ; Infrared transmittance: wavelength 780nm-1200nm, transmittance ≥80%; infrared rays can be transmitted when irradiated by a conventional infrared gun; Haze: ≤1.0%; Visual: If an item 5 cm behind (below) the sample can be clearly seen with the naked eye through the sample, and its outline is blurry, it is considered unqualified and therefore judged as not visible.

[0037] Alcohol resistance: Stress loading test: Add 3 ml of 75% alcohol at a fixed deflection of 0.3% at three points, let stand for 3 minutes and observe whether the experimental sample breaks.

[0038] Scratch resistance: According to GMW 14688 standard, method A, 10N load, scratch-resistant head diameter: 1mm, speed: 1000±50mm / min, evaluate the degree of whitening, requiring ΔL≤2.

[0039] Comparison Example Currently, there are no commercially available high-gloss black paint-free materials that allow infrared light to pass through and make objects visible to the naked eye.

[0040] Figure 1 The image shows a 2.5mm thick sheet of the injection-molded high-gloss black paint-free material, which is the best performing material available in the market for high gloss black paint-free coating. It is clear that the present invention (left) is visible, while the existing product (right) is not.

[0041] Comparative Example 1 PMMA resin 1:100Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 1:0.2Kg. The resulting product has a Vicat softening temperature of 106℃, high gloss black color, and 88% infrared transmittance, but a haze of 80.5%, making it impossible to see objects behind the sample with the naked eye. Furthermore, it failed the alcohol resistance test (fracture test), and its impact resistance and scratch resistance for simply supported beams without notches failed the test.

[0042] Comparative Example 2 PMMA resin 2: 100Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product has a Vicat softening temperature of 96℃, high gloss black color, infrared transmittance of 88%, fails the unnotched impact test and scratch resistance test in simply supported beams, and the alcohol resistance test result shows fracture.

[0043] Comparative Example 3 PMMA resin 1: 100Kg; silica 0.3Kg; silicone oil 1.5Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product passed the scratch resistance test, but failed the alcohol resistance test (fracture test and impact test for a simply supported beam without notches).

[0044] Comparative Example 4 PMMA resin 1: 75Kg; PC resin 1: 25Kg; polyester modified silicone 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product has a hazy appearance (haze 98.4) and color dispersion, L=13.3, and is not transparent to infrared light when irradiated with a conventional infrared gun.

[0045] Comparative Example 5 PMMA resin 1: 75Kg; PC resin 3: 25Kg; polyester modified silicone 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product has a hazy appearance (haze 95.5) and color dispersion, L=9.5, and is not transparent to infrared light when irradiated with a conventional infrared gun.

[0046] Comparative Example 6 PMMA resin 1: 75Kg; PC resin 2: 25Kg; silica 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product has acceptable scratch resistance, but is not visible to the naked eye. Example 1

[0047] PMMA resin 1: 75Kg; PC resin 2: 25Kg; polyester-modified silicone: 0.3Kg; silicone oil: 1.2Kg; antioxidant: 0.2Kg; UV stabilizer: 0.2Kg; pigment 2: 0.2Kg. The resulting product exhibits satisfactory scratch resistance, alcohol resistance, and is visible. It is translucent under standard infrared irradiation, has a Vicat softening temperature of 110℃, and achieves a notched impact strength of 27kJ / m for a simply supported beam. 2 High gloss black with L=0.55, infrared transmittance 85%, and haze meets requirements. Example 2

[0048] PMMA resin 1: 70Kg; PC resin 2: 30Kg; polyester-modified silicone: 0.3Kg; silicone oil: 1.2Kg; antioxidant: 0.2Kg; UV stabilizer: 0.2Kg; pigment 2: 0.2Kg. The resulting product exhibits satisfactory scratch resistance, alcohol resistance, and is visible. It is translucent under standard infrared irradiation, has a Vicat softening temperature of 113℃, and achieves an impact strength of 29kJ / m for a simply supported beam without notches. 2 High gloss black with L=0.6, infrared transmittance 83%, and haze qualified. Example 3

[0049] PMMA resin 1: 65Kg; PC resin 2: 35Kg; polyester-modified silicone 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product is scratch-resistant, alcohol-resistant, and visible. It transmits infrared light under standard infrared gun irradiation. (See attached image.) Figure 2 (2.5mm thickness), Vicat softening temperature is 116℃, and the unnotched impact strength of a simply supported beam is 32kJ / m. 2 High gloss black with L=0.8, infrared transmittance 82%, haze 0.85%.

[0050] Figure 3 The injection-molded sheet, made from the best-performing high-gloss black paint-free material on the market, was tested for both visual and infrared light. The sheet was 2.5mm thick. It is clear that this invention allows infrared light to pass through when irradiated with a conventional infrared gun, while existing products do not.

[0051] With PMMA and PC in the specified ratio, and with the addition of other components, the Vicat temperature exceeds 115℃, exhibiting good heat resistance, and the impact strength is greater than 30, demonstrating good mechanical properties. Example 4

[0052] PMMA resin 1: 72Kg; PC resin 2: 28Kg; polyester modified silicone 0.25Kg; silicone oil 1.25Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product is high-gloss black, with satisfactory scratch resistance, alcohol resistance, and is visible. It is translucent under conventional infrared gun irradiation, and meets the requirements for Vicat softening temperature, unnotched impact test of simply supported beam, and haze. Example 5

[0053] PMMA resin 1: 63Kg; PC resin 2: 37Kg; polyester-modified silicone 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.24Kg. The resulting product meets scratch resistance standards, is resistant to alcohol without breaking, is visible, and transmits infrared light under normal infrared gun irradiation. See [reference needed]. Figure 4 (2.5mm thickness).

[0054] Comparative Example 7 PMMA resin 1: 65Kg; PC resin 2: 35Kg; silicone oil 1.5Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product failed the scratch resistance test and the unnotched impact test on a simply supported beam. Furthermore, even after increasing the silicone oil from 1.2Kg to 1.8Kg, the unnotched impact test on the simply supported beam still did not exceed 25kJ / m. 2 It does not meet the basic requirements. Although it can transmit infrared light, its infrared transmittance is only 79%.

[0055] Comparative Example 8 PMMA resin 1: 65Kg; PC resin 2: 35Kg; polyester modified silicone 1.5Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 2: 0.2Kg. The resulting product is invisible, has high haze (far exceeding 1%), and is not infrared compliant. Other properties were not tested.

[0056] Comparative Example 9 PMMA resin 1: 65Kg; PC resin 2: 35Kg; polyester modified silicone 0.3Kg; silicone oil 1.2Kg; antioxidant 0.2Kg; UV stabilizer 0.2Kg; pigment 1 or pigment 3: 0.2Kg. The resulting product is high-gloss black, but invisible and infrared-blocking. Other properties were not tested.

[0057] Comparative Example 10 PMMA resin 1: 65Kg; PC resin 2: 35Kg; graphite powder: 0.3Kg; silicone oil: 1.2Kg; antioxidant: 0.2Kg; UV stabilizer: 0.2Kg; pigment 2: 0.2Kg. The resulting product has an infrared transmittance of 76%, a haze greater than 1%, and an L value of 1.93, which is greater than 1.5.

[0058] Comparative Example 11 Referring to Example 3, the preparation method differs; the step of polyester-modified silicone composite oil-based blackening is omitted, and all raw materials are directly mixed and extruded into granules. The resulting product has a haze of 1.3% and L=1.7.

[0059] Comparative Example 12 Referring to Example 1, the difference is that the amount of pigment 2 used is 0.1 kg. The resulting product does not have a high-gloss black color and cannot be used as a paint-free coating material.

[0060] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0061] This invention addresses the need for visible, infrared-transmitting, paint-free materials. Using PMMA / PC as the base material, a new material system is developed through the synergistic effect of pigments and additives. It maintains the conventional high-gloss black paint-free performance while adding infrared transmission and visibility, solving the technical problem that existing high-gloss black paint-free materials are not visible. This provides materials for this special application scenario, and the heat resistance, scratch resistance, and impact resistance also meet the basic requirements, enabling industrial applications.

Claims

1. A high heat-resistant, infrared-transmitting, spray-free PMMA / PC material, the raw materials for which are prepared include PMMA, PC, polyester-modified silicone, silicone oil, additives and pigment, wherein the pigment is oil-based black.

2. The high heat-resistant, infrared-transmitting, paint-free PMMA / PC material according to claim 1, characterized in that, The mass ratio of PMMA to PC is (60-80):(20-40); with the sum of the masses of PMMA and PC being 100%, the mass of polyester-modified silicone is 0.1%-0.5%, the mass of silicone oil is 1%-1.7%, the mass of additives is 0.2%-0.6%, and the mass of pigment is 0.1%-0.3% and greater than 0.1%.

3. The high heat-resistant, infrared-transmitting, paint-free PMMA / PC material according to claim 2, characterized in that, The mass ratio of PMMA to PC is (60-70):(30-40); with the sum of the masses of PMMA and PC being 100%, the mass of polyester-modified silicone is 0.2%-0.4%, the mass of silicone oil is 1.2%-1.5%, the mass of additives is 0.3%-0.5%, and the mass of pigment is 0.15%-0.25%.

4. The high heat-resistant, infrared-transmitting, paint-free PMMA / PC material according to claim 1, characterized in that, The raw materials for PC preparation include dimethyl carbonate and alcohol; additives include antioxidants and UV stabilizers.

5. The preparation method of the high heat-resistant, infrared-transmitting, spray-free PMMA / PC material according to claim 1, characterized in that, The process includes the following steps: melting and mixing raw materials including PMMA, PC, polyester-modified silicone, silicone oil, additives, and pigments to obtain a high heat-resistant, infrared-transmitting, spray-free PMMA / PC material.

6. The preparation method of the high heat-resistant, infrared-transmitting, spray-free PMMA / PC material according to claim 5, characterized in that, Polyester-modified silicone and oil-based black are first mixed at 55-65℃ to obtain polyester-modified silicone composite oil-based black, which is then mixed with PMMA, PC, silicone oil and additives, fed and extruded to obtain a high heat-resistant infrared-transmitting PMMA / PC material that does not require spraying.

7. A functional material, the raw materials for which are prepared include the above-mentioned high heat-resistant, infrared-transmitting, spray-free PMMA / PC material.

8. The application of the high heat-resistant infrared-transmitting, paint-free PMMA / PC material of claim 1 in the preparation of black infrared-transmitting materials.

9. The application of the high heat-resistant infrared-transmitting, spray-free PMMA / PC material of claim 1 in the preparation of a visible black infrared-transmitting material.

10. The application of the high heat-resistant infrared-transmitting, paint-free PMMA / PC material of claim 1 in the preparation of a visible high-gloss black infrared-transmitting material; or the application of the above-mentioned high heat-resistant infrared-transmitting, paint-free PMMA / PC material in the preparation of a visible high-gloss black infrared-transmitting material.

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