Aging evaluation and monitoring method for transparent organic coating

Abstract

The invention relates to a transparent organic coating aging evaluation and monitoring method, which comprises the following steps of: completely covering an unaged transparent organic coating film or a quartz glass sheet coated with the unaged transparent organic coating film on the surface of a solar cell device for full-spectrum light source irradiation, and calibrating the original light transmission of the organic coating by utilizing the measured short-circuit current of the solar cell device. And completely covering the transparent organic coating sample aged for a certain time on the surface of the solar cell device, and performing the same operation to obtain a short-circuit current value of the corresponding time. By calculating the change of the difference value of the detected short-circuit current before and after aging, the reduction degree of the light transmittance of the coating is evaluated, and then the aging degree of the coating is reflected; the method has the advantages of simplicity and convenience in operation, wide application range, flexibility, portability and capability of performing in-situ real-time monitoring, and has an important value for realizing efficient and convenient evaluation on the aging of the organic coating.

Description

Technical Field

[0001] The invention belongs to the technical field of organic protective coatings, and in particular relates to an aging evaluation and monitoring method for a transparent organic coating. Background Art

[0002] Organic coatings can effectively extend the service life of substrates by forming a physical barrier between the substrate and the service environment. They are widely used in the protection of various substrates such as metal, wood, fiber, plastic, glass, etc. However, the molecular chain segments of organic coatings will undergo reactions such as breakage and recombination under the coupling of various environmental factors such as light, high temperature, humidity, solution media, and microorganisms, resulting in the degradation of various properties of the coating, such as optics and mechanics. If they are not discovered and maintained and replaced in time, the safety of the protective performance of the substrate will be seriously damaged.

[0003] Light transmittance is one of the important indicators for measuring the degree of aging of transparent organic coatings. Traditional light transmittance testing is mainly characterized and measured by measuring the UV-visible transmittance curve of the sample. There are limitations such as expensive specific instruments, cumbersome operation steps, and difficulty in achieving in-situ monitoring. Therefore, it is urgent to develop simple, efficient, and in-situ organic coating aging evaluation methods. Summary of the invention

[0004] In order to overcome the problems existing in the prior art, the present invention provides an aging evaluation and monitoring method for a transparent organic coating.

[0005] A method for evaluating and monitoring the aging of a transparent organic coating, wherein the transparent organic coating is based on the photoelectric conversion characteristics of photovoltaic materials, and comprises: completely covering the surface of a solar cell device with an unaged transparent organic coating film or a quartz glass sheet after coating thereof and an aged transparent organic coating sample respectively, and conducting a full-spectrum light source irradiation test for a period of time or an outdoor aging monitoring test under natural light conditions, to measure the short-circuit current of the solar cell device after irradiation; calculating a current difference based on the obtained short-circuit current, and evaluating the degree of reduction in the light transmittance of the coating based on the current difference or the change in each short-circuit current, thereby reflecting the aging degree of the transparent organic coating.

[0006] According to the above aspects and any possible implementation, an implementation is further provided, wherein the transparent organic coating is one of water-based, oily or emulsion-type epoxy resin, polyurethane, polyurea, polyester, acrylic resin, and silicone resin.

[0007] According to the aspects and any possible implementations described above, an implementation is further provided, wherein the area of ​​the unaged or aged transparent organic coating film, or the coated quartz glass sheet is greater than or equal to the surface area of ​​the solar cell device, and the thickness of the organic coating film or the coating applied on the quartz glass sheet is in the range of 10 μm to 5 mm.

[0008] According to the aspects described above and any possible implementation methods, an implementation method is further provided, wherein the aging includes natural aging or artificial accelerated aging, and the artificial accelerated aging includes a combination of one or more of ultraviolet aging, xenon lamp aging, hot air aging, temperature alternating aging, ozone aging, wet heat aging, and medium aging.

[0009] According to the above aspects and any possible implementation, an implementation is further provided, wherein the solar cell device comprises one or more combinations of silicon solar cells, polycrystalline thin film cells, organic thin film cells, and dye-sensitized cells.

[0010] According to the aspects and any possible implementations described above, an implementation is further provided, wherein the full-spectrum light source includes natural sunlight in a stable state or simulated sunlight of various powers.

[0011] According to the above aspects and any possible implementation, an implementation is further provided, wherein the full-spectrum light source irradiation test specifically comprises the following steps:

[0012] (1) completely covering the surface of a solar cell device with an unaged transparent organic coating film or a quartz glass sheet coated thereon, exposing the solar cell device to a full-spectrum light source at a fixed distance and fixed power, and measuring the short-circuit current I0 of the solar cell device after a period of time to calibrate the original light transmittance of the unaged transparent organic coating film or the quartz glass sheet coated thereon;

[0013] (2) The transparent organic coating that has been aged for a certain period of time is then completely covered on the surface of the solar cell device, and the solar cell device is exposed to a full-spectrum light source at the same fixed distance and fixed power, and the short-circuit current I of the solar cell device is measured. t , used to correspond to the light transmittance of organic coatings after a certain period of aging;

[0014] (3) Calculate the short-circuit current I0 and I before and after aging t The difference changes, and the degree of decrease in light transmittance of the transparent organic coating is evaluated based on the difference change, thereby reflecting the degree of aging of the coating.

[0015] According to the above aspects and any possible implementation, an implementation is further provided, wherein the outdoor aging monitoring test under natural light conditions specifically comprises the following steps:

[0016] (1) placing solar cell devices with and without transparent organic coatings side by side outdoors at an exposure location without being blocked by buildings or vegetation;

[0017] (2) Set the short-circuit current value of the solar device to the minimum critical value I min , when the short-circuit current I of the solar cell device not covered with the transparent organic coating is measured re Above the critical value I min When I re The short-circuit current I of the solar cell device covered with a transparent organic coating device is measured coating The difference I loss , used to correspond to changes in the light transmittance of organic coatings;

[0018] (3) By comparing the re Under the condition of value, I loss The changes over time are used to evaluate the changes in the transparent organic coating, thereby reflecting the degree of aging of the transparent organic coating.

[0019] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the period of time is 10-40 minutes, and the certain time is 0-12 days.

[0020] According to the above aspects and any possible implementation manner, an implementation manner is further provided, wherein the measurement is implemented by a current measuring device connected to the solar cell device.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention completely covers the surface of a solar cell device with an unaged transparent organic coating film or a quartz glass sheet after coating thereof for full-spectrum light source irradiation, and uses the measured short-circuit current of the solar cell device to calibrate the original light transmittance of the organic coating. Then, a transparent organic coating sample that has been aged for a certain period of time is completely covered on the surface of the solar cell device, and the same operation is performed to obtain the short-circuit current value of the corresponding time. By calculating the difference change in the short-circuit current detected before and after aging, the degree of reduction in the light transmittance of the coating is evaluated, and then the degree of aging of the coating is reflected; in an outdoor exposure experiment, a solar cell device covered with a coating and a device not covered with a coating are placed in an experimental site, and the short-circuit current of the two devices is collected and recorded using an output signal collection device, and the short-circuit current signal error caused by the change in the irradiation intensity of the natural light source is corrected using the device not covered with a coating, thereby realizing accurate monitoring of the light transmittance of the coating, and then monitoring the aging process of the coating. The present invention has the advantages of simple operation, wide application range, flexibility and portability, and can be used for in-situ real-time monitoring, and is of great value in realizing efficient and convenient evaluation of organic coating aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the epoxy resin coating film in Example 1 being irradiated with a full-spectrum light source.

[0024] Figure 2 This is the short-circuit current value change chart for 20 minutes before aging of the acrylic resin coating film.

[0025] Figure 3 This is a curve diagram of the average short-circuit current value change of the polyurethane coating in Example 3 after aging for different times and irradiating with a full-spectrum light source for 20 minutes, and a point diagram of the transmittance at 550nm after a fixed aging time (0 day, 4 days, 8 days, and 12 days).

[0026] Figure 4 Schematic diagram of outdoor aging monitoring test of the polyurethane resin coating film in Example 4.

[0027] Figure 5 This is a graph showing the variation of short-circuit current with test time collected during the outdoor aging experiment of the polyurethane resin coating film in Example 4. DETAILED DESCRIPTION

[0028] In order to better understand the technical solution of the present invention, the content of the present invention includes but is not limited to the specific implementation methods described below, and similar technologies and methods should be considered to be within the scope of protection of the present invention. In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0029] It should be clear that the embodiments described in the present invention are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0031] The present invention provides an aging evaluation and monitoring method for a transparent organic coating, wherein the transparent organic coating is based on the photoelectric conversion characteristics of photovoltaic materials, and comprises: completely covering the surface of a solar cell device with an unaged transparent organic coating film or a quartz glass sheet after coating thereof, and an aged transparent organic coating sample respectively, and conducting a full-spectrum light source irradiation test or an outdoor aging monitoring test under natural light conditions for a period of time, to measure the short-circuit current of the solar cell device after irradiation; calculating a current difference according to the obtained short-circuit current, and evaluating the degree of decrease in the light transmittance of the coating according to the current difference or the change of each short-circuit current, thereby reflecting the aging degree of the transparent organic coating. The photoelectric conversion of the solar cell device depends on the irradiation intensity value of the incident light, and there is a positive correlation between its short-circuit current value and the light irradiation intensity. The present invention utilizes this law, and reflects the aging degree of the light transmittance of the coating by covering the organic transparent coating before and after aging on the surface of the solar cell device, and measuring its short-circuit current value under the irradiation of the full-spectrum light source or natural light source, wherein the period of time is preferably 10-40 minutes, and the aging time is 0-12 days, preferably greater than or equal to 1 day.

[0032] Preferably, the transparent organic coating is one of water-based, oily or emulsion-type epoxy resin, polyurethane, polyurea, polyester, acrylic resin and silicone resin.

[0033] Preferably, the area of ​​the unaged or aged transparent organic coating film or the coated quartz glass sheet is greater than or equal to the surface area of ​​the solar cell device, and the thickness of the organic coating film or the coating applied on the quartz glass sheet ranges from 10 μm to 5 mm.

[0034] Preferably, the aging includes natural aging or artificial accelerated aging. The two aging methods are in different aging environments. Natural aging is usually exposed to actual outdoor environments, while artificial accelerated aging is carried out under specific aging conditions in the laboratory. The artificial accelerated aging includes one or more combinations of ultraviolet aging, xenon lamp aging, hot air aging, temperature alternating aging, ozone aging, damp heat aging, and medium aging.

[0035] Preferably, the solar cell device comprises one or more combinations of silicon solar cells, polycrystalline thin film cells, organic thin film cells, and dye-sensitized cells. The solar cell device has good outdoor stability to ensure that its output signal is easy to collect. 2 ) when the short-circuit current value is not less than 100mA.

[0036] Preferably, the full-spectrum light source includes natural sunlight in a stable state or simulated sunlight of various powers, and the irradiance of the light source is not less than 100W / m 2 .

[0037] Preferably, the full-spectrum light source irradiation test specifically includes the following steps:

[0038] (1) Completely cover the surface of the solar cell device with an unaged transparent organic coating film or a quartz glass sheet after coating, and expose the solar cell device at a fixed distance (ensuring that the simulated sunlight generated by the light source is uniform and fully irradiated on the surface of the solar cell device) and a fixed power (the irradiation intensity of the light source is not less than 100 W / m 2 ) under the irradiation of the full spectrum light source for a period of time, not less than 60s, to measure the short-circuit current I0 of the solar cell device, which is used to calibrate the original light transmittance of the unaged transparent organic coating film or the quartz glass sheet after coating;

[0039] (2) The transparent organic coating that has been aged for an aging test period is then completely covered on the surface of the solar cell device, and the solar cell device is exposed to a full-spectrum light source at the same fixed distance and fixed power to measure the short-circuit current I of the solar cell device. t , used to correspond to the light transmittance of organic coatings after a certain period of aging. The specific aging time depends on the design of the aging experiment, usually from several hours to several days;

[0040] (3) Calculate the short-circuit current I0 and I before and after aging t The difference I0-I t The difference change is used to evaluate the degree of decrease in light transmittance of the transparent organic coating, thereby reflecting the degree of aging of the coating.

[0041] Preferably, the outdoor aging monitoring test under natural light conditions specifically includes the following steps:

[0042] (1) placing solar cell devices with and without transparent organic coatings side by side outdoors at an exposure location without being blocked by buildings or vegetation;

[0043] (2) The solar device without transparent organic coating is set to be exposed to sunlight with an intensity of 100 W / m 2 The short-circuit current value is the minimum critical value I min , when the short-circuit current I of the solar cell device not covered with the transparent organic coating is measured re Above the critical value I min When I re The short-circuit current I of the solar cell device covered with a transparent organic coating device is measured coating The difference I loss , used to correspond to the change in light transmittance of the organic coating, I loss =I re -I coating ;

[0044] (3) By comparing the re Under the condition of value, I loss The changes over time are used to evaluate the changes in the transparent organic coating, thereby reflecting the degree of aging of the transparent organic coating. re If the values ​​are the same, then I loss The value is increasing, indicating that the light transmittance of the coating is reduced due to yellowing, chalking and increased surface roughness, and the degree of coating aging is aggravated.

[0045] Preferably, the measurement is achieved by a current measuring device connected to the solar cell device, and the current measuring device is an ammeter.

[0046] The following specific embodiments are used to illustrate:

[0047] Example 1

[0048] 1. Make epoxy resin into an organic coating film with a side length of 12 cm and a thickness of 0.5 mm.

[0049] 2. Cover the surface of an organic photovoltaic cell with a side length of 10 cm with an epoxy resin coating film and expose it to a full-spectrum light source. Use an ammeter to measure the short-circuit current I0 of the organic photovoltaic cell for 20 minutes.

[0050] 3. Next, the epoxy resin coating film was exposed to a damp heat aging box for a 7-day damp heat aging accelerated test.

[0051] 4. After the aging test, the epoxy resin coating film was again covered on the surface of the organic photovoltaic cell with a side length of 10 cm and exposed to the full spectrum light source. The short-circuit current I of the organic photovoltaic cell was measured for 20 minutes using an ammeter. t .

[0052] 5. Determine the aging degree of the epoxy resin coating film by calculating the difference in short-circuit current before and after 7 days of damp heat aging.

[0053] like Figure 1 As shown, the epoxy resin coating film of Example 1 of the present invention completely covers the surface of the organic photovoltaic cell device, and the real-time short-circuit current value is obtained by short-circuiting the two electrodes of the organic photovoltaic cell device. The obtained short-circuit current I0 (about 30 mA) is significantly greater than I t (about 25 mA), indicating that the transparency of epoxy resin is significantly reduced after aging.

[0054] Example 2

[0055] 1. Make acrylic resin into an organic coating film with a side length of 12 cm and a thickness of 5 mm.

[0056] 2. Cover the surface of a polycrystalline silicon cell with a side length of 10 cm with an acrylic resin coating film and expose it to a full-spectrum light source. Use an ammeter to measure the short-circuit current I0 of the polycrystalline silicon cell for 20 minutes.

[0057] 3. Next, the acrylic resin coating film was exposed to a UV aging box for a 4-day accelerated wet heat aging test.

[0058] 4. After the aging test, the acrylic resin coating film was again covered on the surface of the polycrystalline silicon cell with a side length of 10 cm and exposed to the full spectrum light source. The short-circuit current I of the polycrystalline silicon cell was measured for 20 minutes using an ammeter. t .

[0059] 5. The aging degree of the acrylic resin coating film was determined by calculating the difference in short-circuit current before and after 4 days of UV aging.

[0060] like Figure 2 As shown, it can be found that before the aging of the acrylic resin coating film in Example 2 of the present invention, during the 20 minutes of full-spectrum light source irradiation, the short-circuit current value of the polycrystalline silicon cell is relatively stable at about 28 mA, and its short-circuit current value does not show obvious changes during the test, and the measurement error is small, indicating that the method of measuring the short-circuit current under full-spectrum irradiation to evaluate the light transmittance of the coating is stable and reliable.

[0061] Example 3

[0062] 1. Spray the polyurethane resin evenly on the surface of quartz glass with a side length of 12 cm and a thickness of 3 mm. The thickness after curing is 10 μm.

[0063] 2. Cover the surface of an organic photovoltaic cell with a side length of 10 cm with a quartz glass plate coated with polyurethane and expose it to a full-spectrum light source. Use an ammeter to measure the short-circuit current I0 of the organic photovoltaic cell for 20 minutes.

[0064] 3. Next, the quartz glass plate coated with polyurethane was exposed to a UV aging box for a 12-day UV accelerated aging test.

[0065] 4. After the aging test, the quartz glass plate coated with polyurethane was again covered on the surface of the organic photovoltaic cell with a side length of 10 cm and exposed to the full spectrum light source. The short-circuit current I of the organic photovoltaic cell was measured for 20 minutes using an ammeter. t .

[0066] 5. Determine the aging degree of the coating by calculating the difference in short-circuit current during 12 days of UV aging.

[0067] Figure 3 The short-circuit current average value change curve of the polyurethane coating in Example 3 after aging for different time periods and irradiation with full-spectrum light source for 20 minutes and the transmittance point diagram at 550nm after aging for a fixed time period (0 day, 4 days, 8 days, 12 days). It can be found from the figure that the short-circuit current value change of the organic photovoltaic cell is consistent with the change trend of the polyurethane coating, and both decrease synchronously with the increase of aging time.

[0068] Example 4

[0069] 1. Apply polyurethane resin evenly on the surface of the organic photovoltaic cell with a side length of 10 cm to form a polyurethane film.

[0070] 2. Place the organic photovoltaic cell covered with the film and the organic photovoltaic cell not covered with the film on the same exposure rack and connect them to a current collection device.

[0071] 3. The short-circuit current I of the uncoated device recorded re and I coating , find I re The short circuit current I of the device with overlay coating coating The difference I loss .

[0072] 4. By comparing the same re In this case, I loss Determine the degree of environmental aging of the coating by analyzing the changes over time.

[0073] Figure 4This is a schematic diagram of the outdoor aging monitoring test of the polyurethane resin coating film in Example 4. The polyurethane resin coating film completely covers the surface of the organic photovoltaic cell device. The coated organic photovoltaic cell and the uncovered coating cell are fixed on the same exposure rack, and the output current of the organic photovoltaic cell is collected by the output signal (short-circuit current) collection device.

[0074] Figure 5 The short-circuit current collected in the outdoor aging experiment of the polyurethane resin coating film in Example 4 changes with the test time. It can be seen that as the test time increases, the short-circuit current difference I loss The short-circuit current I coating It keeps decreasing, indicating that the light transmittance of the polyurethane resin coating film keeps decreasing and the degree of aging keeps increasing.

[0075] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not depart from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for evaluating and monitoring aging of a transparent organic coating, wherein the transparent organic coating is based on the photoelectric conversion characteristics of a photovoltaic material, characterized in that: include: An unaged transparent organic coating film or a quartz glass sheet coated with it, and an aged transparent organic coating sample are respectively completely covered on the surface of a solar cell device to carry out a full-spectrum light source irradiation test or an outdoor aging monitoring test under natural light conditions for a period of time to measure the short-circuit current of the solar cell device after irradiation; a current difference is calculated based on the obtained short-circuit current, and the degree of reduction in the light transmittance of the coating is evaluated based on the current difference or the change in each short-circuit current, thereby reflecting the aging degree of the transparent organic coating.

2. The aging evaluation and monitoring method of a transparent organic coating according to claim 1, characterized in that: The transparent organic coating is one of water-based, oily or emulsion-type epoxy resin, polyurethane, polyurea, polyester, acrylic resin and silicone resin.

3. The aging evaluation and monitoring method of a transparent organic coating according to claim 1 or 2, characterized in that: The area of ​​the unaged or aged transparent organic coating film or the coated quartz glass sheet is greater than or equal to the surface area of ​​the solar cell device, and the thickness of the organic coating film or the coating coated on the quartz glass sheet ranges from 10 μm to 5 mm.

4. The aging evaluation and monitoring method of a transparent organic coating according to claim 1, characterized in that: The aging includes natural aging or artificial accelerated aging, and the artificial accelerated aging includes one or more combinations of ultraviolet aging, xenon lamp aging, hot air aging, temperature alternating aging, ozone aging, damp heat aging, and medium aging.

5. The aging evaluation and monitoring method of a transparent organic coating according to claim 1, characterized in that: The solar cell device comprises one or more combinations of silicon solar cells, polycrystalline thin film cells, organic thin film cells, and dye-sensitized cells.

6. The aging evaluation and monitoring method of a transparent organic coating according to claim 1, characterized in that: The full-spectrum light source includes natural sunlight in a stable state or simulated sunlight of various powers.

7. The aging evaluation and monitoring method of a transparent organic coating according to claim 6, characterized in that: The full-spectrum light source irradiation test specifically includes the following steps: (1) completely covering the surface of a solar cell device with an unaged transparent organic coating film or a quartz glass sheet coated thereon, exposing the solar cell device to a full-spectrum light source at a fixed distance and fixed power, and measuring the short-circuit current I0 of the solar cell device after a period of time to calibrate the original light transmittance of the unaged transparent organic coating film or the quartz glass sheet coated thereon; (2) The transparent organic coating that has been aged for a certain period of time is then completely covered on the surface of the solar cell device, and the solar cell device is exposed to a full-spectrum light source at the same fixed distance and fixed power, and the short-circuit current I of the solar cell device is measured. t , used to correspond to the light transmittance of organic coatings after a certain period of aging; (3) Calculate the short-circuit current I0 and I before and after aging t The difference changes, and the degree of decrease in light transmittance of the transparent organic coating is evaluated based on the difference change, thereby reflecting the degree of aging of the coating.

8. The aging evaluation and monitoring method of a transparent organic coating according to claim 1, characterized in that: The outdoor aging monitoring test under natural light conditions specifically includes the following steps: (1) placing solar cell devices with and without transparent organic coatings side by side outdoors at an exposure location without being blocked by buildings or vegetation; (2) Set the short-circuit current value of the solar device to the minimum critical value I min , when the short-circuit current I of the solar cell device not covered with the transparent organic coating is measured re Above the critical value I min When I re The short-circuit current I of the solar cell device covered with a transparent organic coating device is measured coating The difference I loss , used to correspond to changes in the light transmittance of organic coatings; (3) By comparing the re Under the condition of value, I loss The changes over time are used to evaluate the changes in the transparent organic coating, thereby reflecting the degree of aging of the transparent organic coating.

9. The method for evaluating and monitoring aging of a transparent organic coating according to claim 7, characterized in that: The period of time is 10-40 minutes, and the certain period of time is 0-12 days.

10. The method for evaluating and monitoring aging of a transparent organic coating according to claim 7 or 8, characterized in that: The measurement is achieved by a current measuring device connected to the solar cell device.

Images