A silicon-based composite material photovoltaic module frame, a preparation method and application thereof

Abstract

The application provides a silicon-based composite photovoltaic module frame and a preparation method and application thereof, raw materials: modified nano-silica 40-55 parts, base resin 15-25 parts, heat-resistant resin 10-20 parts, additive 8-12 parts, and impact modifier 3-5 parts. The modified nano-silica is nano-silica after surface activation treatment by polystyrene-acrylate graft copolymer, so as to help improve the adding proportion in the formula. Compared with the prior art, the silicon-based composite material used in the frame is prepared by the method of blending and extrusion of nano-silica, high molecular resin and other additives, meets the strength requirement of the frame for photovoltaic modules in various environments, and has high heat resistance and durability.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic module technology, specifically relating to a silicon-based composite material photovoltaic module frame, its preparation method, and its application. Background Technology

[0002] Currently, the vast majority of photovoltaic (PV) frames are made of aluminum alloy profiles. With the rapid development of the PV industry, the demand for aluminum in the PV sector has also increased year by year. The upstream material for aluminum alloy profiles is electrolytic aluminum, and the production process of electrolytic aluminum consumes a large amount of electricity and generates significant carbon emissions. According to data from EcoNet, taking 2020 as an example, based on the calculation that producing one ton of electrolytic aluminum requires approximately 13,500 kilowatt-hours of electricity, the total electricity consumption of the entire industry was approximately 501.2 billion kilowatt-hours. The electricity consumption of the electrolytic aluminum industry alone accounted for 6.67% of the total electricity consumption of the entire society that year.

[0003] With increasing demands for low energy consumption, the electrolytic aluminum industry is facing greater challenges in deploying new production capacity. Driven by both rapid demand growth and limited capacity expansion, photovoltaic module manufacturers have been searching for higher-performance and more cost-competitive materials to replace aluminum alloys.

[0004] In addition, aluminum alloy photovoltaic frames have problems such as poor corrosion resistance in high salt spray environments, heavy weight, and easy ion migration between the frame and the solar cells under high voltage, which can cause performance degradation of the module (PID effect). Therefore, there is an urgent need to develop a new type of composite material photovoltaic frame product to overcome the above problems and promote the further development of the photovoltaic new energy industry. Summary of the Invention

[0005] The purpose of this invention is to provide a silicon-based composite material photovoltaic module frame and its preparation method. The silicon-based composite material used in the frame is prepared by a co-extrusion method using nano-silica, polymer resin and other additives, which meets the strength requirements of photovoltaic modules for the frame under various environments and has high heat resistance and durability.

[0006] Another objective of this invention is to provide an application of silicon-based composite material photovoltaic module frames for photovoltaic module manufacturing.

[0007] The specific technical solution of this invention is as follows:

[0008] A silicon-based composite photovoltaic module frame comprises the following raw materials in parts by weight: 40-55 parts modified nano-silica, 15-25 parts matrix resin, 10-20 parts heat-resistant resin, 8-12 parts additives, and 3-5 parts impact modifier.

[0009] The modified nano-silica content in the frame of the silicon-based composite photovoltaic module is ≥40%.

[0010] The modified nano-silica is nano-silica that has undergone surface activation treatment with polystyrene-acrylate graft copolymer to help increase its addition ratio in the formulation.

[0011] The amount of the polystyrene-acrylate graft copolymer used is 2-5% of the mass of nano-silica.

[0012] The modified nano-silica is prepared as follows: First, the nano-silica is preheated to 100-110℃ and stirred for 10-15 minutes until its water content is less than 0.3%. Then, polystyrene-acrylate graft copolymer is added and modified and activated for 5-15 minutes until the temperature reaches 120℃ to ensure that the nano-silica and the surface-modified resin are fully integrated. Finally, it is cooled to room temperature to obtain modified nano-silica.

[0013] The polystyrene-acrylate graft copolymer has a molecular weight of 80,000-120,000.

[0014] The matrix resin is one or more of polyvinyl chloride (PVC) resin and polymethyl methacrylate (PMMA) resin.

[0015] The polyvinyl chloride (PVC) resin is SG-5 type PVC resin, with a degree of polymerization of 981-1135.

[0016] The polymethyl methacrylate (PMMA) resin is a high melt index PMMA resin with a melt index of 8-10 g / 10 min.

[0017] The heat-resistant resin is one or more of chlorinated polyvinyl chloride (CPVC) and silicone resin; preferably, the CPVC is of type J-700 and has a degree of polymerization of 700-1000.

[0018] The additives are selected from one or more combinations of heat stabilizers, antioxidants, titanium dioxide, and processing modifiers.

[0019] The heat stabilizer is a calcium-zinc stabilizer or an organotin stabilizer;

[0020] The antioxidant is selected from antioxidant 1010;

[0021] The titanium dioxide is rutile titanium dioxide;

[0022] The processing modifier is an acrylate copolymer;

[0023] The impact modifier is one or more of impact-resistant ACR, chlorinated polyethylene (CPE), ethylene-vinyl acetate copolymer (EVA), and acrylonitrile-butadiene-styrene copolymer (ABS).

[0024] The silicon-based composite photovoltaic module frame has a tensile strength ≥38MPa, an elongation at break ≥37%, a Vicat softening temperature ≥95℃, and a dimensional change rate ≤1.1% after heating.

[0025] The present invention provides a method for preparing a silicon-based composite photovoltaic module frame, comprising the following steps:

[0026] 1) Add the raw materials of the formula to the hot mixer, and when the temperature of the mixture reaches 120°C, transfer it to the cold mixer, use stirring to reduce the temperature to 40°C to 45°C, and then homogenize it in the storage tank for 24 hours.

[0027] 2) The silicon-based composite photovoltaic module frame is obtained by extruding through an extruder with a photovoltaic frame mold and then drying and cooling.

[0028] This invention provides an application of a silicon-based composite material photovoltaic module frame for photovoltaic module manufacturing.

[0029] In this invention, nano-silica, a nanomaterial with high surface area and unique surface properties, can achieve uniform distribution in a PVC matrix and interact with PVC molecules. The high surface area and reinforcing effect of nano-silica can improve the strength, stiffness, and wear resistance of PVC, thereby enhancing its tensile strength and yield strength. Furthermore, nano-silica also possesses good weather resistance, flame retardancy, and electrical insulation properties, which can delay the aging of PVC products, enhance flame retardancy, and reduce the risk of flame spread and release of harmful gases in the event of a fire.

[0030] Modifying nano-silica with polystyrene-acrylate graft copolymers can effectively integrate it with the matrix resin, playing a crucial role in increasing the nano-silica content. Through physical blending at a certain temperature, the acrylate groups in the polystyrene-acrylate graft copolymer can form hydrogen bonds with the hydroxyl groups on the surface of nano-silica, resulting in a more robust composite structure. The introduction of polystyrene-acrylate graft copolymers can effectively improve the dispersibility, interfacial compatibility, filling amount, and reinforcing effect of nano-silica in the matrix resin, thereby enhancing the performance of the composite material.

[0031] The silicon-based composite photovoltaic module frame provided by this invention is mainly used in photovoltaic new energy modules to replace traditional metal frame materials. Compared with the prior art, it has the following advantages: (1) The high content of nano-silica significantly enhances the strength of the material, enabling it to meet the strength requirements of photovoltaic modules for the frame in various environments; (2) The high content of nano-silica significantly improves the heat resistance and dimensional stability of the matrix polymer material in different environments, meeting the durability requirements of photovoltaic frame materials; (3) Silicon-based composite materials have excellent resistance to a variety of chemical substances, reducing the risk of material damage due to chemical corrosion and increasing the service life of the material; (4) Compared with traditional metal frame materials, the silicon-based composite photovoltaic frame of this invention can effectively avoid the PID effect; (5) Compared with aluminum alloy photovoltaic frames, the silicon-based composite photovoltaic frame of this invention is lighter in weight, which is more conducive to handling, transportation and installation; (6) Nano-silica can also prevent crack propagation by absorbing and dispersing stress, further improving the durability of the material. This mechanism enables silicon-based composite materials to maintain excellent performance under extreme conditions, such as high temperature, high pressure and chemical corrosion environments. Attached Figure Description

[0032] Figure 1 The images show the test samples prepared for this invention before and after the DH1000 damp heat test. The left side is before the test, and the right side is after the test. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the embodiments.

[0034] The polymethyl methacrylate (PMMA) resin used in the following examples is a high melt index PMMA resin with a melt index of 8-10 g / 10 min. The polyvinyl chloride (PVC) resin is SG-5 type PVC resin with a degree of polymerization of 981-1135; the heat-resistant resin is polyvinyl chloride CPVC, model J-700, with a degree of polymerization of 700-1000.

[0035] Example 1

[0036] A silicon-based composite photovoltaic module frame, the silicon-based composite photovoltaic module frame comprising the raw materials shown in the weight parts of Example 1 in Table 1.

[0037] The preparation method of the silicon-based composite photovoltaic module frame is as follows: The raw materials are put into a hot mixer according to the proportions in Table 1 and mixed. During the mixing process, volatiles and moisture are discharged through a vacuum dehumidification system. When the mixing temperature reaches 120°C, the mixture is discharged into a cold mixer. After stirring and cooling to 40-45°C, impurities are removed by a Roots blower and a vibrating screen. The mixture is then sent to a storage tank for homogenization for 24 hours by negative pressure air to obtain the silicon-based composite photovoltaic module frame mixture. The mixture is then transported to an extruder platform, extruded by a screw extruder, cooled and shaped, and cut to obtain the silicon-based composite photovoltaic module frame.

[0038] Example 2

[0039] A silicon-based composite photovoltaic module frame, wherein the raw material input ratio is as shown in Table 1 Example 2 by weight, and the preparation method is the same as in Example 1.

[0040] Example 3

[0041] A silicon-based composite photovoltaic module frame, wherein the raw material input ratio is as shown in Table 1 Example 3 by weight, and the preparation method is the same as in Example 1.

[0042] Example 4

[0043] A silicon-based composite photovoltaic module frame, wherein the raw material input ratio is as shown in Table 1 Example 4 by weight, and the preparation method is the same as in Example 1.

[0044] Comparative Example 1

[0045] A silicon-based composite photovoltaic module frame, wherein the raw material input ratio is as shown in Table 1 Comparative Example 1 by weight, and the preparation method is the same as in Example 1.

[0046] Comparative Example 2

[0047] A silicon-based composite photovoltaic module frame, wherein the raw material input ratio is as shown in Table 1 Comparative Example 1 by weight, and the preparation method is the same as in Example 1.

[0048] Table 1. Formulations of silicon-based composite photovoltaic module frames in each embodiment and comparative example.

[0049]

[0050] The modified nano-silica mentioned in Table 1 is nano-silica that has undergone surface activation treatment with polystyrene-acrylate graft copolymer, and the amount of polystyrene-acrylate graft copolymer is 3% of the mass of nano-silica.

[0051] The modified nano-silica is prepared by: first, preheating the nano-silica to 100-110°C, stirring for 15 minutes to reduce its water content to below 0.3%, then modifying and activating it for 15 minutes until the temperature reaches 120°C to ensure that the nano-silica and the surface-modified resin are fully fused, and then cooling it to room temperature to obtain the modified nano-silica.

[0052] The products of the above embodiments and comparative examples were subjected to performance tests. The test performance and methods were as follows: tensile strength and elongation at break were measured according to GB / T1040.2-2022 standard; Vicat softening temperature was measured according to GB / T 1633-2000 standard; dimensional change rate after heating was measured according to GB / T 8814-2017 standard, and the specific test conditions for dimensional change rate after heating were: 100±2℃, 1 hour; the damp heat test (DH1000h) of the photovoltaic module was performed according to MQT 13 in IEC 61215-2; the salt spray test was performed according to IEC 61701. The performance technical indicators of the products prepared in the above embodiments and comparative examples are shown in Table 2.

[0053] Table 2 shows the test results of relevant performance and technical indicators for each embodiment and comparative example.

[0054]

[0055]

[0056] Comparative Example 2: The physical properties of the frame prepared by this formulation were poor, and damp heat test and salt spray resistance test were not carried out.

[0057] The data underlined above do not meet the requirements of this invention.

[0058] Table 2 shows that the tensile strength, heat resistance, and dimensional stability of the silicon-based composite photovoltaic module frames produced using the formulations of Examples 1-4 are significantly improved compared to Comparative Example 1. Example 1 exhibits the best overall performance, indicating that a 43% addition of nano-silica premix significantly enhances the overall performance of the composite material. Meanwhile, Comparative Example 2 shows that the unactivated nano-silica exhibits significant differences in dispersibility and compatibility within the overall formulation system, and its overall plasticizing properties are poor. In conclusion, silicon-based composite photovoltaic frames can meet the current requirements of photovoltaic modules for mechanical properties, heat resistance, durability, and salt spray resistance, while avoiding the PID effect of traditional metal photovoltaic frames, and offering a significant cost advantage. The application of silicon-based composite photovoltaic frames will further promote the development of the photovoltaic new energy industry.

[0059] The above detailed description of a silicon-based composite photovoltaic module frame, its preparation method, and its application, with reference to the embodiments, is illustrative rather than limiting. Several embodiments may be listed within the defined scope. Therefore, variations and modifications without departing from the overall concept of the present invention should be within the protection scope of the present invention.

Claims

1. A silicon-based composite material photovoltaic module frame, characterized in that, The silicon-based composite photovoltaic module frame comprises the following raw materials in parts by weight: 40-55 parts modified nano-silica, 15-25 parts matrix resin, 10-20 parts heat-resistant resin, 8-12 parts additives, and 3-5 parts impact modifier. The modified nano-silica is nano-silica that has undergone surface activation treatment with polystyrene-acrylate graft copolymer; The modified nano-silica content in the frame of the silicon-based composite photovoltaic module is ≥40%. The amount of the polystyrene-acrylate graft copolymer used is 2-5% of the mass of nano-silica; The modified nano silica is prepared by: first, preheating the nano silica to 100~110℃, stirring for 10~15 min to make its water content less than 0.3%, then adding polystyrene-acrylate graft copolymer, modifying and activating for 5~15 min until the temperature reaches 120℃, and then cooling to room temperature to obtain modified nano silica. The silicon-based composite photovoltaic module frame has a tensile strength ≥38MPa, an elongation at break ≥37%, a Vicat softening temperature ≥95℃, and a dimensional change rate ≤1.1% after heating. The matrix resin is one or more of polyvinyl chloride (PVC) resin, polystyrene-acrylic acid copolymer, or PMMA resin; The heat-resistant resin is one or more of chlorinated polyvinyl chloride (CPVC) and silicone resin.

2. The silicon-based composite photovoltaic module frame according to claim 1, characterized in that, The additives are selected from one or more combinations of heat stabilizers, antioxidants, titanium dioxide, and processing modifiers.

3. A method for preparing a silicon-based composite photovoltaic module frame as described in claim 1 or 2, characterized in that, The preparation method includes the following steps: 1) Add the raw materials of the formula to the hot mixer, and when the temperature of the mixture reaches 120°C, transfer it to the cold mixer, use stirring to reduce the temperature to 40°C to 45°C, and then homogenize it in the storage tank for 24 hours. 2) The silicon-based composite photovoltaic module frame is obtained by extruding through an extruder with a photovoltaic frame mold and then drying and cooling.

4. An application of the silicon-based composite photovoltaic module frame as described in claim 1 or 2, characterized in that, Used in the manufacture of photovoltaic modules.

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