Method for manufacturing transparent polymer-based materials for solar panels
Through the combination of activated polycarbonate and grafted nanoparticles, a transparent polymer-based composite material is formed, which solves the problems of scratch resistance and production cost in photovoltaic panels, and achieves a more efficient and environmentally friendly photovoltaic panel front panel material.
Patent Information
- Application Number
- CN202380073753.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-10-20
- Filing Date
- 2023-10-20
- Publication Date
- 2025-05-30
AI Technical Summary
The application of polycarbonate as a front plate in photovoltaic panels is limited by its moderate scratch resistance and high cost industrial production methods, and the complex dispersion of nanoparticles in polycarbonate affects its ultimate behavior.
Through the combination of activated polycarbonate and grafted nanoparticles, a transparent polymer-based composite material is formed, and the scratch resistance and dispersion of polycarbonate are improved by using carbonate ester exchange reaction and graft copolymer technology.
It achieves improved scratch resistance and dispersion of polycarbonate, reduces production costs, and provides a more environmentally friendly and efficient alternative glass material solution.
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Figure CN120077082A_ABST
Abstract
Description
BACKGROUND OF THE INVENTION
[0001] Capturing solar energy through photovoltaic panels for electricity generation is considered one of the most promising applications in the field of renewable energy. Due to its rapid growth prospects and sustainability benefits, the photovoltaic market has received increasing attention in the past decade, involving significant investments and R&D projects around the world. The current market is mainly dominated by rigid, crystalline silicon-based photovoltaic (PV) systems, which typically consist of a rigid aluminum frame and a glass front plate. Replacing the glass used as the front plate in rigid PV solar panels with highly transparent polymer-based materials and composites (such as polycarbonate) will significantly increase the use and market share of hydrocarbon-based polymer materials.
[0002] Compared with inorganic glass, polycarbonate has many advantages, including much lighter materials and higher impact resistance. However, polycarbonate has several limitations that prevent its widespread application in such applications, especially its moderate scratch resistance. Another challenge is that the industrial production of transparent polycarbonate is carried out using the melt transcarbonation method at elevated temperatures with high costs and long residence times, which may lead to side reactions and increase costs. Another synthetic method is interfacial phosgenation, which is very dangerous due to the use of toxic reagents (such as COCl 2 ). Interfacial phosgenation also produces a large amount of wastewater, which is generated by washing away the impurities of the film.
[0003] Many studies have reported the benefits of incorporating reinforcements into organic matrices. The most common reinforcements encountered in the literature are silica nanoparticles. For a given volume fraction, the incorporation of such reinforcements has shown an improvement in the scratch resistance of polycarbonate compared to that of the original polymer. The second advantage of using nanoparticles is that an improvement can usually be observed by incorporating a small amount of nanoparticles, which can offset the higher costs. The dispersion of nanoparticles in polycarbonate is a very critical parameter that affects the final behavior of the polymer. For example, the dispersion depends on various factors, including the shape and size of the nanoparticles and their interaction with the polycarbonate matrix.
[0004] Despite the progress made in recent years, using nanoparticles to improve the scratch resistance of polycarbonate remains complex. Chemical modification of the surface of the nanoparticles can enhance their chemical compatibility with polycarbonate to some extent; however, the nanoparticles still need to be firmly bonded to the polymer to produce a durable organic matrix. SUMMARY OF THE INVENTION
[0005] This summary is provided to introduce some select concepts that will be further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
[0006] In one aspect, embodiments disclosed herein relate to a transparent polymer-based composite material that includes an activated polycarbonate and nanoparticles grafted to the activated polycarbonate.
[0007] In another aspect, embodiments disclosed herein relate to a transparent polymer-based composite material synthesized from an activated polycarbonate and one or more nanoparticles grafted to the activated polycarbonate, the activated polycarbonate formed by a transesterification reaction of a mixture of a carbonic acid substance having terminal ester groups and bisphenol A with sodium hydroxide and orthodichlorobenzene.
[0008] In another aspect, embodiments disclosed herein relate to grafting poly(methyl methacrylate) (PMMA) to an activated polycarbonate via one or more ester bonds to form an activated polycarbonate-poly(methyl methacrylate) copolymer.
[0009] In another aspect, embodiments disclosed herein relate to inorganic fillers grafted to an activated polycarbonate via one or more urethane bonds.
[0010] In another aspect, embodiments disclosed herein relate to a method for preparing a transparent polymer-based composite material. The method includes preparing an activated polycarbonate and grafting nanoparticles to the activated polycarbonate.
[0011] Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 Illustrates a transesterification reaction for synthesizing an activated polycarbonate according to an embodiment of the present disclosure.
[0013] Figure 2 Illustrates a reaction for forming an activated PC-g-PMMA graft copolymer according to an embodiment of the present disclosure.
[0014] Figure 3 Illustrates a reaction for grafting nanoparticles with an activated polycarbonate according to an embodiment of the present disclosure.
[0015] Figure 4 and Figure 5 are schematic diagrams of a method for preparing a transparent polymer-based material according to an embodiment of the present disclosure. DETAILED DESCRIPTION
[0016] In the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
[0017] Throughout the application, ordinal numbers (e.g., first, second, third, etc.) may be used as adjectives for elements (i.e., any nouns in the application). The use of ordinal numbers is not intended to imply or create any particular ordering of the elements, nor to limit any element to being only a single element, unless explicitly disclosed, such as by the use of terms like "before," "after," "single," and other such terms. Instead, the use of ordinal numbers is to distinguish elements. As an example, a first element is different from a second element, and the first element may contain more than one element and be after (or before) the second element in the ordering of the elements.
[0018] Embodiments of the present disclosure relate to a method of using an activated polycarbonate to prepare a transparent polycarbonate film. The transparent polycarbonate film can be used for offset glass in renewable, industrial, and automotive applications. Compared to inorganic glass, polycarbonate has many advantages, such as being lighter in weight and having stronger impact resistance. However, polycarbonate also has limitations that prevent its widespread use in such applications, such as its moderate scratch resistance. Another challenge is the use of a melt carbonate exchange method with high cost and high residence time at elevated temperatures, which can lead to increased costs.
[0019] Many studies have reported the benefits of incorporating reinforcements into an organic matrix, and the most common reinforcement encountered in the literature is silica nanoparticles. However, the dispersion of nanoparticles in polycarbonate is a very critical parameter that affects the final behavior of the polymer. Chemical modification of the surface of the nanoparticles may be a solution to enhance the chemical compatibility of the nanoparticles with polycarbonate; however, the nanoparticles still need to be firmly bound to the polymer to produce a durable organic matrix.
[0020] In one or more embodiments, a polycarbonate having functionalized nanoparticles chemically anchored by chemical bonds can be produced. Introducing reactive functional groups on the surface of the nanoparticles imparts reactive properties to them as part of a chemical reaction and anchors them to the polymer matrix, thus ensuring their uniform dispersion in the polymer matrix.
[0021] Polycarbonate is a thermoplastic polymer that contains carbonate groups in its chemical structure. Products made from polycarbonate usually contain the precursor monomer bisphenol A or BPA. Generally, two production methods have been proven to be able to produce high-quality polycarbonate resins. The first method is the two-phase interfacial method, and the second method is the melt transesterification method. The transesterification method does not require a solvent, but long residence times at elevated temperatures may cause problems with the resulting product. To reduce the required reaction temperature and time, activated carbonate substances with electron-withdrawing functional groups substituted on the phenolic leaving group can be utilized. The introduction of known electron-withdrawing groups in the ortho or para position results in activated carbonates.
[0022] Figure 1 is a schematic diagram of the synthesis of activated polycarbonate by transesterification reaction. Activated polycarbonate can be formed by reacting a mixture of carbonate substances (100) with terminal ester groups and BPA (102) (or other bisphenol substances) with sodium hydroxide (NaOH) and ortho-dichlorobenzene (oDCB). In one or more embodiments, the mixture contains bis(methyl salicyl) carbonate in an amount in the range of 1 gram to 5 grams (such as 2.5 grams to 3.5 grams), BPA in an amount in the range of 0.5 gram to 4 grams (such as 1.5 grams to 2.5 grams), NaOH in an amount in the range of 0.1 milligram to 3 milligrams (such as 0.5 milligram to 1.5 milligrams), and oDCB in an amount in the range of 10 milliliters to 50 milliliters (such as 20 milliliters to 30 milliliters). In the melt transesterification method, the mixture can be heated to a temperature between 60°C and 160°C, such as 120°C. After transcarbonation, bisphenol-A-polycarbonate can be synthesized. Methyl 2-hydroxybenzoate (106) may be a byproduct of this reaction. Activated carbonate substances (such as activated polycarbonate) have electron-withdrawing functional groups substituted on the phenolic leaving group.
[0023] Figure 2 is a schematic diagram of a reaction for preparing a transparent composite according to an embodiment of the present disclosure. In particular, Figure 2Illustrated is the formation of a graft copolymer between an activated polycarbonate and poly(methyl methacrylate) (PMMA). The depicted reaction may occur in the presence of an organometallic catalyst (tin(II) 2-ethylhexanoate). PMMA (200) reacts with the activated polycarbonate (104) via an ester bond to form an activated polycarbonate-poly(methyl methacrylate) copolymer (202). PMMA (200) can be a homopolymer or a copolymer. The PMMA (200) polymer or copolymer may have a weight average molecular weight of at least 3000 g / mol. In some embodiments, the PMMA (200) polymer or copolymer may have a weight average molecular weight of at least 15000 g / mol, 100000 g / mol, 120000 g / mol, 150000 g / mol, 200000 g / mol, 215000 g / mol, or 250000 g / mol. The PMMA (200) polymer or copolymer may have a weight average molecular weight of up to 330000 g / mol, and in some embodiments, the PMMA (200) polymer or copolymer may have a weight average molecular weight of up to 350000 g / mol, and in some embodiments, the PMMA (200) polymer or copolymer may have a weight average molecular weight of up to 400000 g / mol. It should generally be understood that the PMMA (200) polymer or copolymer is a linear polymer or copolymer.
[0024] In one or more embodiments, the PMMA (200) polymer can be a copolymer containing comonomers. In one or more embodiments, the comonomers can include acrylates such as n-butyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate; methacrylates such as ethyl methacrylate, butyl methacrylate; acrylic acids and methacrylic acids and their salts; fluorinated acrylates; styrene, acrylamide; acrylonitrile; and combinations thereof.
[0025] Figure 3 is a schematic diagram of another reaction for preparing a transparent composite according to an embodiment of the present disclosure. In particular, Figure 3 illustrates the grafting of a filler (300) (or functionalized nanoparticles) into an activated polycarbonate (104) via a urethane bond (302) to enhance the properties of the resulting modified polycarbonate (304), where Y represents the number of repeating methylene groups (CH 2 )). Non-limiting examples of the filler include silica, zinc oxide, titanium oxide (or titanium dioxide), and zirconia or combinations thereof, with a size range of 50 nanometers (nm) to 500 nm. In one or more embodiments, an amine-terminated silane-functionalized inorganic filler (300) reacts with the carbonate groups of the activated polycarbonate (104) to produce a modified polycarbonate (304).
[0026] In one or more embodiments, the filler consists of nanoparticles. In some embodiments, the nanoparticles are dendritic fibrous nanoparticles (DFNs). In one or more embodiments, the DFNs can be dendritic fibrous silica nanoparticles. The nanoparticles can be prepared by hydrothermal, hydrothermal microwave-assisted techniques, or any other techniques known to those skilled in the art. In one or more embodiments, the nanoparticles can be modified by surface functionalization. In one or more embodiments, the nanoparticles can be chemically modified with a compound such as amine-terminated silane. The chemical modification of each nanoparticle enables it to attach to the activated polycarbonate (104). The introduction of new functional groups on the nanoparticle surface imparts reactive properties to the nanoparticles. Thus, the nanoparticles can participate in chemical reactions and anchor on the polymer matrix.
[0027] In some embodiments, the modification of the polycarbonate reaction can be carried out in a three-necked flask equipped with a stirrer, in the presence of isopropanol as a solvent, at a temperature in the range between 25 °C and 70 °C.
[0028] In some embodiments, the grafting of the activated polycarbonate can be prepared by mixing between 0.1 g and 1 g (such as 0.5 g) of the activated polycarbonate and a solution of between 0.01 g and 0.1 g (such as 0.05 g) of functionalized silica in ethanol in a three-necked flask equipped with a stirrer. After mixing, the mixture can be heated at between 80 °C and 120 °C, such as 100 °C, for about 48 hours. Then, the resulting modified polymer-based composite material (modified polycarbonate) can be collected after evaporation of the solvent.
[0029] The method for manufacturing the nanocomposite composition according to the present disclosure can include various methods such as solution casting, compounding / extrusion, blending, solvent casting, and other formulation techniques. The nanocomposite composition according to the embodiments of the present disclosure generally has physical properties suitable for the intended use of the composition and the articles produced therefrom. Benefiting from the present disclosure, those of ordinary skill in the art will understand that changing the relative amounts and properties of the components of the polymer composition will affect the final properties of the composition. Depending on its end use or application, the resulting nanocomposite composition can be produced in the form of a film or a substrate. The nanocomposite composition can be prepared by any known method for film and substrate formulation, such as in-situ polymerization, solvent casting, blending, and compounding.
[0030] In one or more embodiments, the nanocomposite film can be prepared by solvent casting by dissolving the modified polycarbonate formed as described above at 20% (w / w) in chloroform and then slowly evaporating.
[0031] In some embodiments, the nanocomposite can be formed into a film using conventional film-forming techniques, such as melt compounding and extrusion of the nanocomposite composition. In one or more embodiments, the film of the nanocomposite composition can be prepared using continuous or discontinuous extrusion. In some embodiments, the raw materials can be added to the extruder simultaneously or sequentially in the form of powders, granules, flakes, or as a dispersion of one or more components in a solution, emulsion, and suspension in a liquid, added to the main feeder or secondary feeder to produce an extruded film.
[0032] In some embodiments, the nanoparticles (e.g., silica particles) can be modified with 3-aminopropyltriethoxysilane before reacting with the activated polycarbonate to provide reaction sites for additional polymer attachment on the silica. Then, the silica particles can be dried at 100 °C for about one hour and immediately transferred to a round-bottom flask. A solution of about 10 volume % to 20 volume % (v / v %) of 3-aminopropyltriethoxysilane in toluene can be prepared and added to the flask. The resulting mixture can be refluxed for about one day, and then the suspension can be cooled. The solid product can be separated from the solution by repeated centrifugation using polar and nonpolar solvents. The modified silica powder can be ground into a fine powder. Then, the modified silica can react with the activated polycarbonate (104).
[0033] Figure 4 and Figure 5 are flowcharts illustrating methods for preparing transparent polymer-based materials according to embodiments of the present disclosure. Referring Figure 4 , in the first step (400), bisphenol A reacts with bis(methyl salicyl) carbonate to form an activated polycarbonate. In the next step (402), the activated polycarbonate reacts with a functionalized inorganic filler. In the final step (404), a transparent polymer-based composite material is produced.
[0034] Referring Figure 5 , in the first step (500), an activated polycarbonate-based material is prepared. In the next step (502), the activated polycarbonate-based material reacts with PMMA through a grafting process. In the next step (504), an activated PC-g-PMMA copolymer is produced. In the final step (506), a transparent polymer-based composite material is produced.
[0035] The embodiments disclosed herein describe a new, cost-effective, and environmentally friendly method for synthesizing a transparent polymer-based composite material for replacing the glass front plate of solar panels used in photovoltaic applications. In particular, the method according to the embodiments of the present disclosure can be used to produce cost-effective and energy-efficient solar panels by employing activated transesterification and optimizing the average molecular weight of the film. The front plate of a typical photovoltaic panel is made of glass. Using polycarbonate as a substitute is an attractive solution due to its low density and high impact resistance. Additional applications include, but are not limited to, manufacturing materials that can be used in the construction, automotive, and aerospace industries.
[0036] Although only a few exemplary embodiments have been described in detail above, those skilled in the art will readily understand that many modifications can be made to the exemplary embodiments without materially departing from the invention. Accordingly, all such modifications are intended to be included within the scope of the present disclosure as defined by the following claims.
[0037] The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.
[0038] As used herein and in the appended claims, the words "comprising", "having", and "including" and all grammatical variations thereof are intended to have an open, non-limiting meaning that does not exclude additional elements or steps.
[0039] "Optionally" means that the subsequent described event or circumstance may or may not occur. The description includes instances where the event or circumstance occurs and instances where the event or circumstance does not occur.
[0040] Ranges can be expressed as from about a particular value to about another particular value, including the endpoint values. When expressing such ranges, it should be understood that another embodiment is from a particular value to another particular value, and all particular values within that range and their combinations.
[0041] Although the present disclosure includes a limited number of embodiments, those skilled in the art who benefit from the present disclosure will understand that other embodiments can be designed without departing from the scope of the present disclosure. Accordingly, the scope should be limited only by the appended claims.
Claims
1. A transparent polymer-based composite material, comprising: Activated polycarbonate formed by a transesterification reaction of a mixture of a carbonic acid substance having terminal ester groups and bisphenol A with sodium hydroxide and orthodichlorobenzene; and One or more nanoparticles grafted onto the activated polycarbonate.
2. The transparent polymer-based composite material according to claim 1, wherein the one or more nanoparticles are at least one poly(methyl methacrylate) (PMMA), and the at least one PMMA is grafted onto the activated polycarbonate through one or more ester bonds to form an activated polycarbonate-poly(methyl methacrylate) copolymer.
3. The transparent polymer-based composite material according to claim 1 or 2, wherein the one or more nanoparticles are inorganic fillers, and the inorganic fillers are grafted onto the activated polycarbonate through one or more urethane bonds.
4. The transparent polymer-based composite material according to any one of the preceding claims, wherein the carbonic acid substance is bis(methyl salicyl) carbonate.
5. The transparent polymer-based composite material according to any one of the preceding claims, wherein the one or more nanoparticles are selected from the group consisting of silica, titanium oxide, zinc oxide, and zirconium oxide.
6. The transparent polymer-based composite material according to claim 5, wherein each nanoparticle is modified with a reactive functional group.
7. The transparent polymer-based composite material according to claim 6, wherein the reactive functional group is an amine-terminated silane.
8. The transparent polymer-based composite material according to any one of the preceding claims, wherein each nanoparticle is modified with 3-aminopropyltriethoxysilane.
9. A method for preparing a transparent polymer-based composite material, comprising: Forming an activated polycarbonate by a transesterification reaction of a mixture of a carbonic acid substance having terminal ester groups and bisphenol A with sodium hydroxide and orthodichlorobenzene; Reacting one or more nanoparticles with the activated polycarbonate; and Grafting the one or more nanoparticles onto the activated polycarbonate.
10. The method according to claim 9, wherein forming the activated polycarbonate comprises: Mixing bis(methyl salicyl) carbonate in an amount in the range of 1 g to 5 g, bisphenol A in an amount in the range of 0.5 g to 4 g, sodium hydroxide in an amount in the range of 0.1 mg to 3 mg, and orthodichlorobenzene in an amount in the range of 10 mL to 50 mL, such as 20 mL to 30 mL; and Heating the mixture to a temperature between 60 °C and 160 °C.
11. The method according to claim 9 or 10, wherein grafting the one or more nanoparticles onto the activated polycarbonate comprises reacting at least one poly(methyl methacrylate) (PMMA) with the activated polycarbonate in the presence of tin(II) 2-ethylhexanoate to form an activated polycarbonate-poly(methyl methacrylate) copolymer.
12. The method according to any one of claims 9 to 11, wherein grafting the one or more nanoparticles onto the activated polycarbonate comprises: Mix the activated polycarbonate with functionalized silica in ethanol, wherein the amount of the activated polycarbonate comprised is in the range of 0.1 g to 1 g, and the amount of the functionalized silica comprised is in the range of 0.01 g to 0.1 g; Heat the mixture to a temperature between 80 °C and 120 °C for about 48 hours to produce a modified polycarbonate; and Dissolve the modified polycarbonate in chloroform at 20% (w / w), and then evaporate.
13. The method according to any one of claims 9 to 12, comprising modifying the one or more nanoparticles with 3-aminopropyltriethoxysilane prior to reacting with the activated polycarbonate.