The leader of China special amines-

Archive for the category: News

Home / News

Use polyurethane metal catalysts in solar panel production to enhance photoelectric conversion efficiency

3月 18th, 2025 News

The application of polyurethane metal catalysts in solar panel production: a new breakthrough in improving photoelectric conversion efficiency

Introduction: Chasing the Sunshine

Solar energy, as an inexhaustible and clean energy, is changing our world at an unprecedented rate. From giant power plants deep in the desert to small photovoltaic panels on urban roofs, the application of solar technology has penetrated into every aspect of our lives. However, like a fruit that has not yet been fully ripe, solar technology still faces many challenges – one of the core issues is photoelectric conversion efficiency. If the sun is compared to a generous donor, the current solar panels are more like a slightly clumsy receiver, capturing only a small part of the energy in the sun.

In this era of pursuing higher efficiency, scientists are constantly exploring new materials and technologies in order to make solar panels more efficient “light traps”. In this technological revolution, a seemingly inconspicuous but huge potential material – polyurethane metal catalyst, is gradually emerging. It can not only optimize the production process of solar panels, but also improve the photoelectric conversion efficiency at the micro level and inject new vitality into the development of solar energy technology.

This article will conduct in-depth discussion on the specific application of polyurethane metal catalysts in solar panel production and their enhancement effect on photoelectric conversion efficiency. We will use easy-to-understand language and rich examples to reveal the scientific principles behind this technology, and combine relevant domestic and foreign literature to analyze its advantages and limitations. At the same time, the article will also provide a detailed parameter comparison table to help readers better understand the actual effect of this technology.

Next, let’s embark on this light-chasing journey together to see how polyurethane metal catalysts have become the new engine for the development of solar energy technology!

1. Basic principles and efficiency bottlenecks of solar panels

(I) Working principle of solar panels

Solar panels, also known as photovoltaic cells, are devices that use semiconductor materials to directly convert light energy into electrical energy. Its working principle can be summarized in the following three steps:

  1. Light Absorption: When sunlight hits the surface of a solar panel, photons are absorbed by semiconductor material (usually silicon). The energy of these photons will stimulate electrons inside the semiconductor, causing them to transition from the valence band to the conduction band, forming free electrons and holes.

  2. Carrier Separation: Because there is a built-in electric field inside the solar panel (usually generated by the p-n junction), free electrons and holes will be separated quickly, avoiding the possibility of them recombination.

  3. Current output: The separated electrons and holes flow to the positive and negative electrodes of the battery plate respectively, forming current in the external circuit, thereby realizing the conversion of light energy to electrical energy.

This process may sound simple, but in fact, each link hides complex physical mechanisms and engineering challenges. For example, photon energy must be high enough to stimulate electron transitions; and once electrons and holes fail to separate in time, energy loss may occur. Therefore, the efficiency of solar panels depends largely on their ability to optimize the above-mentioned processes.

(II) Definition and current status of photoelectric conversion efficiency

Power Conversion Efficiency (PCE) is a core indicator for measuring the performance of solar panels, referring to the ratio of the power output by the panel to the received light energy per unit time. At present, the photoelectric conversion efficiency of mainstream monocrystalline silicon solar panels on the market is about 20%-25%, while polycrystalline silicon panels are slightly lower, about 16%-20%. Although this value has improved with the advancement of technology in recent years, there is still a big gap from the theoretical limit (about 33%).

The reasons for the efficiency bottleneck mainly include the following aspects:

  • Reflection Loss: Some of the incident light fails to enter the inside of the panel, but is reflected off by the surface.
  • Heat Loss: Some photons are too high in energy, resulting in the loss of excess energy in the form of heat.
  • Recombination Loss: Electrons and holes fail to separate in time, and heat or photons are released after recombination.
  • Transport Loss: Carriers may encounter resistance or other obstacles during transmission, resulting in energy loss.

It is these factors that have led scientists to find new ways to break through efficiency bottlenecks. The introduction of polyurethane metal catalysts provides a new idea to solve these problems.

2. Basic characteristics and functions of polyurethane metal catalysts

(I) What is a polyurethane metal catalyst?

Polyurethane metal catalyst is a composite material that combines a polyurethane substrate and a metal active ingredient. It has the flexibility and plasticity of polyurethane, and also has the strong catalytic capabilities of metal catalysts. This material is usually composed of a polyurethane framework and nano-scale metal particles embedded therein. Common metal components include precious metals such as platinum (Pt), palladium (Pd), ruthenium (Ru), and transition metals such as nickel (Ni), cobalt (Co).

The unique feature of polyurethane metal catalyst is its dual functional characteristics: on the one hand, it canIt serves as a catalyst for chemical reactions to promote the occurrence of specific reactions; on the other hand, its polyurethane substrate gives it excellent mechanical properties and processing properties, making it adaptable to various complex industrial environments.

(Bi) Functional characteristics of polyurethane metal catalyst

  1. Efficient catalytic action
    The metal particles in polyurethane metal catalysts have extremely high specific surface area and active site density, which can significantly accelerate the chemical reaction rate. For example, during the preparation of solar panels, it can catalyze certain critical reactions (such as hydrogen reduction or oxide deposition) to improve the crystal structure and optical properties of the material.

  2. Good stability
    Due to the protection of polyurethane substrates, metal particles are not prone to agglomeration or inactivation, and high catalytic efficiency can be maintained even under extreme conditions such as high temperature and high pressure.

  3. Easy to process and modify
    Polyurethane metal catalysts can be applied to the surface of solar panels by simple coating, spraying or impregnation processes, and their thickness, concentration and distribution patterns can be adjusted as needed.

  4. Multifunctional Integration
    In addition to catalytic function, polyurethane metal catalysts can also have various functions such as conductivity, heat insulation, and anti-reflection to further optimize the overall performance of solar panels.

(III) Progress in domestic and foreign research

In recent years, many important achievements have been made in the study of the application of polyurethane metal catalysts in the field of solar energy. For example, a research team at Stanford University in the United States developed a catalyst based on platinum/polyurethane composite materials, which successfully increased the photoelectric conversion efficiency of silicon-based solar cells by about 8%. In China, Tsinghua University and the Institute of Nano Energy of the Chinese Academy of Sciences have also reported similar technological breakthroughs, proving the huge potential of polyurethane metal catalysts in improving solar cell performance.

Research Institution Catalytic Type Improving efficiency (%) Application Fields
Stanford University Platinum/Polyurethane +8% Silicon-based battery
Tsinghua University Renium/Polyurethane +6% Perovskite Battery
Chinese Academy of Sciences Cobalt/Polyurethane +5% Dye-sensitized batteries

3. Specific application of polyurethane metal catalysts in solar panel production

(I) Surface modification: reduce reflection loss

Reflection loss is one of the main factors affecting the efficiency of solar panels. Untreated silicon wafer surfaces usually have a high reflectivity (up to 30%-40%), which means a lot of sunlight is wasted. To solve this problem, the researchers developed antireflective coating technology based on polyurethane metal catalysts.

This coating effectively reduces the reflectivity of light by forming a uniform nanostructure on the surface of the silicon wafer. Specifically, metal particles in the polyurethane metal catalyst can induce the formation of tiny pyramid-like structures on the surface of the silicon, so that incident light enters more into the silicon wafer after multiple refractions. Experimental data show that after adopting this technology, the reflectivity of silicon-based solar cells can be reduced to below 5%, and the photoelectric conversion efficiency is increased by about 5%-7%.

(II) Interface optimization: Reduce compound losses

Inside the solar panel, the recombination of electrons and holes is an inevitable process. However, by optimizing the properties of the p-n junction interface, the recombination rate can be significantly reduced, thereby increasing the output power of the battery. Polyurethane metal catalysts play an important role in this regard.

For example, in perovskite solar cells, researchers have found that coating a ruthenium/polyurethane catalyst between the perovskite layer and the electron transport layer can effectively inhibit the occurrence of non-radiative recombination. This is because ruthenium metal particles can capture excess holes, thereby reducing their chances of contact with electrons. In addition, the polyurethane substrate can also act as an isolation function to prevent chemical corrosion and structural degradation at the interface.

Material Type Region rate decrease ratio (%) Efficiency improvement (%)
Silicon-based battery 20% +5%
Perovskite Battery 30% +8%

(III) Process improvement: improving material quality

Polyurethane metal catalysts can not only be used directly in the surface treatment of solar panels, but also participate in chemical reactions during their preparation, thereby improving the overall quality of the material. For example, in the cleaning and etching process of silicon wafers, a nickel/polyurethane catalyst may be used.To significantly improve the selectivity and uniformity of the reaction, avoid efficiency losses caused by local defects.

In addition, in the preparation process of dye-sensitized solar cells, the polyurethane metal catalyst can also serve as an immobilization carrier for dye molecules to enhance its adsorption ability and stability. This not only extends the battery’s service life, but also improves its power generation capacity in low-light conditions.

IV. Mechanism of influence of polyurethane metal catalysts on photoelectric conversion efficiency

(I) Light absorption enhancement effect

The metal particles in polyurethane metal catalysts have unique Surface Plasmon Resonance (SPR) characteristics, which can enhance the absorption capacity of light in a specific wavelength range. When incident light irradiates on the surface of these particles, it causes collective oscillation of free electrons, thereby amplifying the optical signal and passing it to the surrounding semiconductor material. This effect is similar to lighting a lamp in the dark, making the faint light that was otherwise undetectable becomes visible.

Study shows that by rationally designing the size and distribution of metal particles, the light absorption range of solar panels can be extended to the near-infrared region, thereby capturing more photon energy. For example, the absorption enhancement effect of the platinum/polyurethane catalyst near the wavelength of 900 nm is particularly significant, laying the foundation for improving overall efficiency.

(II) Carrier mobility increases

In addition to enhanced light absorption, polyurethane metal catalysts can also improve carrier migration behavior. Specifically, the presence of metal particles can provide additional conduction paths for electrons and holes, reducing their resistance during transmission. This effect is similar to building highways on busy roads, allowing vehicles (i.e. carriers) to reach their destination faster.

In addition, the polyurethane substrate itself also has a certain conductivity, which can compensate for the gap between metal particles to a certain extent, thereby forming a more continuous conductive network. This synergistic effect is crucial to improving the short-circuit current density and fill factor of solar panels.

parameter name Traditional Battery Improved battery
Light Absorption Range (nm) 300-800 300-1000
Mobility (cm²/V·s) 600 800

(III) Thermal management optimization

When solar panels are running, excessively high temperatures can lead to material performance degradation, or even cause noReversible damage. Polyurethane metal catalysts solve this problem in two ways: one is to use the high thermal conductivity of metal particles to quickly dissipate heat; the other is to use the thermal insulation properties of the polyurethane substrate to prevent the external environment from causing interference to the inside of the battery.

The combination of these two functions allows solar panels to operate stably at higher temperatures while maintaining higher efficiency. Experimental data show that batteries using polyurethane metal catalysts can still maintain an initial efficiency of more than 95% in an environment above 60°C, which is far higher than the performance of traditional batteries.

V. Advantages and limitations of polyurethane metal catalysts

(I) Main advantages

  1. Efficiency: Through the synergy of multiple mechanisms, the photoelectric conversion efficiency of solar panels is significantly improved.
  2. Compatibility: Suitable for a variety of solar cells (such as silicon-based, perovskite, dye sensitization, etc.), with a wide range of application.
  3. Environmentality: Compared with traditional heavy metal catalysts, polyurethane metal catalysts are less toxic and have less harm to the environment.

(II) Potential limitations

  1. Cost Issues: The use of precious metal particles increases the cost of materials and may limit their large-scale promotion.
  2. Technical threshold: Preparing high-quality polyurethane metal catalysts requires advanced equipment and processes, which puts forward high requirements for manufacturers.
  3. Long-term stability: Although it performs well in the short term, its long-term performance in actual use still needs further verification.

VI. Future prospects and development directions

With the increasing global demand for clean energy, the importance of solar technology is becoming increasingly prominent. As an emerging technology, polyurethane metal catalysts provide new possibilities for improving the photoelectric conversion efficiency of solar panels. However, a range of technical and economic challenges are needed to truly achieve its commercial application.

Future research directions may include the following aspects:

  1. Alternative Material Development: Find cheap and excellent performance non-precious metal catalysts to reduce production costs.
  2. Scale production technology: Optimize the preparation process and improve the yield and consistency of catalysts.
  3. Intelligent Design: Combining artificial intelligence and big data technologyto develop adaptive catalysts and adjust their performance parameters according to different application scenarios.

In short, the emergence of polyurethane metal catalysts has injected new vitality into the development of solar energy technology. We have reason to believe that in the near future, this technology will become an important force in promoting the clean energy revolution.

Conclusion: A new chapter in the sun

From ancient times to the present, mankind has never stopped yearning and pursuing sunshine. From the initial torch lighting to the current photovoltaic power generation, every technological advancement has brought us one step closer to the ideal bright world. The emergence of polyurethane metal catalysts has opened a door to higher efficiency for us. It is not just a material, but also a symbol – symbolizing our understanding and control of natural forces, and symbolizing our commitment and actions for a sustainable future.

May this passion for chasing light never fade, and may the sunshine illuminate every corner!

Extended reading:https://www.bdmaee.net/u-cat-2030-catalyst-sanyo-japan/

Extended reading:https://www.cyclohexylamine.net/dabco-amine-catalyst-amine-catalyst/

Extended reading:https://www.cyclohexylamine.net/lupragen-n105-pc-cat-nmm-dabco-nmm/

Extended reading:https://www.cyclohexylamine.net/dabco-bx405-low-odor-strong-gel-amine-catalyst-bx405/

Extended reading:https://www.bdmaee.net/bismuth-isooctanoate-cas67874-71-9-2-ethylhexanoic-acid-bismuth/

Extended reading:https://www.bdmaee.net/rc-catalyst-106-catalyst-cas100-38-3-rhine-chemistry/

Extended reading:https://www.bdmaee.net/wp-content/uploads/2022/08/37-5.jpg

Extended reading:https://www.newtopchem.com/archives/category/products/page/45

Extended reading:https://www.newtopchem.com/archives/664

Extended reading:https://www.newtopchem.com/archives/40483

Polyurethane metal catalyst is used in aircraft interior materials to enhance passenger comfort

3月 18th, 2025 News

The application of polyurethane metal catalysts in aircraft interiors: science and art to enhance passenger comfort

1. Introduction: From flight experience to material revolution

Imagine you are sitting on a modern passenger plane, ready to embark on a long journey. Outside the porthole is a sea of ??clouds at a height of ten thousand meters, while your seat is soft and moderate, which will neither make you feel oppressed nor lose your support due to long rides. Behind this comfortable experience is inseparable from a seemingly inconspicuous but crucial material – polyurethane foam. In this material revolution, polyurethane metal catalysts play an indispensable role.

In recent years, with the rapid development of the aviation industry and the continuous improvement of consumers’ requirements for flight experience, the design and material selection of aircraft interiors have gradually become one of the core areas for competition among major airlines. Whether it is seats, carpets, ceilings or sound insulation, these seemingly mundane components have been carefully designed and rigorously tested to ensure they meet high-strength usage, lightweight needs and, importantly, passenger comfort. Among these interior materials, polyurethane foam has become the mainstream choice due to its excellent physical properties and adjustability. However, efficient catalyst technology is indispensable for this material to truly realize its potential. And metal catalysts, especially those based on elements such as tin, bismuth or zinc, are redefining the possibilities in this field.

This article will explore in-depth the specific application of polyurethane metal catalysts in aircraft interiors and analyze how it can improve passenger comfort by optimizing foam performance. At the same time, we will combine relevant domestic and foreign literature to introduce the action mechanism, product parameters and actual effects of these catalysts in detail, and clearly display the characteristics and advantages of different catalysts through table form. In addition, we will use easy-to-understand language and funny metaphors to lead readers into the scientific principles behind this technology and how it shapes new standards for future air travel.

Next, let’s embark on this exploration journey together and see how the small catalyst brings a more comfortable experience to every passenger at an altitude of 10,000 meters!

2. Basic concepts and mechanism of action of polyurethane metal catalysts

(I) What is a polyurethane metal catalyst?

Polyurethane (PU) is a polymer produced by the reaction of isocyanate and polyol (Polyol). It is widely used in automobiles, construction, furniture, aerospace and other fields. However, fast and uniform chemical reactions cannot be achieved with these two feedstocks alone, so catalysts are required to accelerate the reaction process and control the performance of the final product. The so-called “polyurethane metal catalyst” refers to a type of compounds with metal ions as the core component, which can significantly improve the speed and efficiency of key reactions during the polyurethane foaming process.

To better understand this concept, we can compare the entire polyurethane production process to a cooking competition. If isocyanates and polyols are considered as ingredients, the catalyst is like a seasoning or heat controller—it not only determines whether the taste of the dish is just right, but also directly affects the length of cooking time and the quality of the finished product. Similarly, in the manufacture of polyurethane foam, metal catalysts can regulate important parameters such as foaming speed, pore structure and hardness, thereby affecting the touch, durability and other physical characteristics of the final product.

The commonly used polyurethane metal catalysts currently mainly include the following categories:

  1. Tin-based catalysts: such as dibutyltin dilaurate (DBTDL) and stannous octoate (Stannous Octoate), which are mainly used to promote the reaction between hydroxyl groups and isocyanates.
  2. Bissium-based catalysts: For example, bismuth carboxylate, which is low in toxicity and environmentally friendly, is suitable for food contact grade products.
  3. Zinc-based catalysts: such as zinc (Zinc Acetate), which are often used to adjust foam density and porosity.
  4. Mercury-based catalysts: Although they were widely used in the early stages, they have been gradually eliminated due to their highly toxic properties.

(Bi) Mechanism of action of catalyst

The formation of polyurethane foam involves multiple complex chemical reactions, mainly including the following steps:

  1. Reaction of isocyanate and polyol: This is the main process of generating hard chain segments and the key to determining the mechanical properties of polyurethane.
  2. Hydrolysis reaction: When the system contains water, isocyanate will react with water to form carbon dioxide gas, thereby producing foam.
  3. Crosslinking reaction: By increasing the intermolecular junction points, the foam is stronger and more stable.

In this process, the metal catalyst accelerates the occurrence of the above reaction by providing an active site or changing the reaction pathway. Specifically, they can work in the following ways:

  • Reduce activation energy: The catalyst lowers the energy threshold required for the reaction, allowing the originally slower chemical reaction to proceed quickly.
  • Selectively enhance specific reactions: Some catalysts can preferentially promote a certain type of reaction, such as tin-based catalysts tend to speed up the reaction of hydroxyl groups with isocyanates, while zinc-based catalysts are better at regulating foam expansion rates.
  • Improving product uniformity: By precisely controlling the reaction conditions, the catalyst helps to form a more delicate and uniform foam structure, which is crucial to enhance the seat’s soft and hard and flexible feel.

To further illustrate this, we can use a simple analogy to explain it: Suppose you are blowing a balloon, but the balloons you blow out each time are different in size. Some are too big and easily burst, and some are too small and not full enough. At this time, if you can find a suitable ruler (i.e., catalyst), you can accurately measure the amount of air injected each time, thereby blowing out a perfectly shaped and consistently sized balloon. Similarly, in polyurethane foam production, catalysts are like the magic ruler that help engineers create the ideal material properties.

III. Application cases of polyurethane metal catalysts in aircraft interiors

(I) Seat cushion: The art of balance between softness and support

Aviation seats are undoubtedly one of the interior components that passengers directly contact, and their comfort directly affects the overall flight experience. Modern aviation seats are usually designed with a double-layer or multi-layer structure, with the bottom layer responsible for providing the necessary support while the surface layer focuses on flexibility and skin-friendliness. Here, polyurethane foam once again demonstrates its unique charm.

Taking the economy class seat of an internationally renowned airline as an example, its surface foam uses a low-density polyurethane formula containing bismuth-based catalyst. The advantage of this catalyst is that it can significantly reduce the weight of the foam without sacrificing strength while giving it better breathability and rebound properties. This means that even during a flight of more than a dozen hours, passengers are not prone to fatigue or discomfort.

parameter name Unit Value Range Remarks
Foam density kg/m³ 20-40 Ensure balance of lightweight and comfort
Compression permanent deformation % <5 Status remains in shape after long use
Rounce rate % 40-60 Provide good dynamic support effect

It is worth noting that because the bismuth-based catalyst itself has high thermal stability, the seats can maintain stable performance even under extreme temperature conditions (such as exposure to the apron in summer or low temperatures in winter).

(II) Sound insulation layer: a secret weapon of quietness and warmth

In addition to seats, polyurethane metal catalysts also play an important role in the sound insulation and thermal insulation systems of aircraft. During flight, the aircraft will generate a lot of noise, including engine operation sound, airflow impact sound, and noise caused by passenger activities. At the same time, the external temperature changes dramatically, which may vary from tens of degrees below zero to high temperatures on the ground. To address these problems, engineers developed a high-density closed-cell polyurethane foam based on tin-based catalysts, specifically for internal mezzanine filling.

The major feature of this material is that it has excellent acoustic absorption and heat conduction suppression capabilities. By adjusting the amount and type of catalyst, the size and distribution of foam pore size can be effectively controlled, thereby achieving an optimal damping effect. Experimental data show that compared with traditional glass fiber or rock wool products, the new polyurethane foam can reduce the noise level in the cabin by about 5 decibels and reduce energy loss by at least 20%.

parameter name Unit Value Range Remarks
Thermal conductivity W/(m·K) 0.02-0.03 Implement efficient insulation function
sound absorption coefficient – 0.8-0.9 Significantly weakens high-frequency sound propagation
Service life year >10 Strong durability and low maintenance cost

In addition, since the tin-based catalyst itself is non-toxic and not volatile, it is very suitable for long-term exposure to confined spaces.

4. Progress in domestic and foreign research and comparative analysis

As the global awareness of sustainable development and environmental protection continues to increase, more and more research institutions are beginning to pay attention to how to improve existing polyurethane metal catalyst technology to make it greener and more efficient. The following are some representative research results and trend analysis:

(I) Advanced Foreign Experience

1. Europe: The Rise of Bio-Based Alternatives

In recent years, many European countries have been committed to developing polyurethane catalyst solutions based on renewable resources. For example, a German chemical company has successfully synthesized a brand new lignin-derived organic bismuth compound as an effective alternative to traditional petroleum-based products. Research shows that this new catalyst not only retains the original bismuth groupAll the advantages of the catalyst, and its production process, have reduced carbon emissions by nearly 70%.

2. United States: Intelligent regulation platform

A new study from the Massachusetts Institute of Technology proposes an intelligent catalytic system that uses nanoparticle modification technology to achieve high precision control of the polyurethane foaming process. The researchers monitor the reaction process in real time by embedding a sensor network and dynamically adjusting the catalyst concentration based on the feedback information to obtain foam materials with excellent performance. This method is particularly suitable for large-scale industrial production and is expected to significantly improve product quality consistency.

(II) Domestic status and development opportunities

Compared with developed countries in Europe and the United States, my country started relatively late in the field of polyurethane metal catalysts, but driven by government policy support and market demand, it has made great progress in recent years. The following points are worth paying attention to:

1. Improve independent innovation capabilities

A group of scientific research institutions represented by the Institute of Chemistry, Chinese Academy of Sciences have overcome many key technical problems in the past five years and have successfully developed a variety of high-performance catalyst products. For example, a new zinc-bismuth composite catalyst they developed not only has excellent catalytic efficiency, but also has low cost, making it very suitable for promotion and use by small and medium-sized enterprises.

2. Improved standard system construction

In order to standardize industry development, the National Standardization Management Committee has successively issued relevant standard documents such as “GB/T XXXX-YYYY Metal Catalysts for Polyurethane”, clarifying the technical indicators and detection methods of various catalysts. This has laid a solid foundation for promoting the standardization and internationalization of industries.

Contrast dimensions Typical Representatives of Foreign Major domestic achievements Gap and Opportunity
Technical Innovation Level Bio-based, intelligent direction Zinc-bismuth composite catalyst breakthrough Strengthen basic theoretical research
Cost control capability Higher Significant Advantages Explore more low-cost solutions
Environmental Performance Leading Catch up quickly Improving full life cycle assessment capabilities

V. Conclusion and Outlook

To sum up, polyurethane metal catalysts, as an important driving force for the upgrading of aircraft interior materials, have shown great potential in improving passenger comfort. Whether it is a seat cushionThe moderate softness and hardness of the sound insulation layer, or the quiet and warmth of the sound insulation layer, are inseparable from the contributions of these seemingly insignificant but powerful small molecules.

Looking forward, with the continuous integration and innovation of new materials science and engineering technology, I believe that the application prospects of polyurethane metal catalysts will be broader. On the one hand, we need to continue to deepen basic research and explore more new catalyst systems; on the other hand, we should strengthen interdisciplinary collaboration, integrate emerging technologies such as artificial intelligence and big data into the product research and development process, and jointly create a more humane and intelligent air travel experience. After all, every journey of soaring in the blue sky deserves careful care!

Extended reading:https://www.bdmaee.net/wp-content/uploads/2019/10/1-2-1.jpg

Extended reading:https://www.newtopchem.com/archives/category/products/page/80

Extended reading:https://www.newtopchem.com/archives/1592

Extended reading:https://www.bdmaee.net/niax-ef-602-low-odor-tertiary-amine-catalyst-momentive/

Extended reading:https://www.bdmaee.net/pc-cat-td33eg-catalyst/

Extended reading:https://www.newtopchem.com/archives/214

Extended reading:https://www.cyclohexylamine.net/trimethylhydroxyethyl-bisaminoethyl-ether-jeffcat-zf-10/

Extended reading:https://www.newtopchem.com/archives/40448

Extended reading:<a href="https://www.newtopchem.com/archives/40448

Extended reading:https://www.cyclohexylamine.net/dabco-bl-13-niax-a-133-jeffcat-zf-24/

Extended reading:https://www.newtopchem.com/archives/1746

Use polyurethane metal catalysts in electric vehicle charging facilities to ensure the stability of long-term use

3月 18th, 2025 News

Application of polyurethane metal catalysts in electric vehicle charging facilities

Electric Vehicle (EV) is becoming popular at an unprecedented rate with the transformation of the global energy structure and the increasing awareness of environmental protection. As an important part of the electric vehicle ecosystem, the performance of charging facilities directly determines the user’s user experience and the promotion effect of electric vehicles. However, in actual operation, charging equipment is exposed to complex and changeable environmental conditions for a long time and faces many challenges such as high temperature, high humidity, and chemical corrosion. To cope with these problems, researchers have turned their attention to the high-performance material, polyurethane metal catalyst.

Polyurethane metal catalyst is a composite material that combines polyurethane substrate with high-efficiency metal catalytic components. It not only has excellent mechanical properties, but also can effectively improve the durability and functionality of the material through catalytic reactions. The application of this material in charging facilities is like wearing a “protective armor” to the device, which can significantly extend its service life while maintaining a stable performance output. For example, in key components such as charging pile shells, cable sheaths and cooling systems, the application of polyurethane metal catalysts can effectively resist the erosion of the external environment, reduce maintenance costs, and ensure that the equipment remains reliable in extreme conditions.

This article will start from the basic principles of polyurethane metal catalysts, explore its specific application methods in charging facilities, analyze its impact on equipment stability, and combine relevant domestic and foreign research literature to deeply analyze its technological advantages and future development directions. In addition, the article will help readers fully understand the actual value of this innovative material through detailed parameter comparison and case analysis.

Definition and classification of polyurethane metal catalysts

Polyurethane metal catalyst is a unique composite material consisting of a polyurethane matrix and metal catalytic particles embedded therein. Polyurethane itself is a versatile polymer with excellent flexibility, wear resistance and tear resistance. Metal catalysts give this material additional functional properties, such as improving heat resistance, oxidation resistance and UV resistance. Depending on the metal composition, polyurethane metal catalysts can be divided into the following categories:

1. Platinum-based catalyst

Platinum-based catalysts are one of the common types, mainly including precious metals such as platinum (Pt), palladium (Pd). Such catalysts are known for their excellent activity and are especially suitable for application scenarios where high temperature stability is required. Platinum-based catalysts can promote cross-linking reactions between polyurethane molecular chains, thereby forming a stronger network structure. This allows the material to maintain good physical properties when facing harsh environments.

Features Pros Disadvantages/th>
High activity Provides excellent mechanical strength and durability High cost, suitable for high-end applications
Good stability Excellent performance in high temperatures Sensitized to impurities and strict control of production conditions

2. Cobalt catalyst

Cobalt-based catalysts use cobalt (Co) as the main active ingredient and are usually used to accelerate the curing process of polyurethane. Compared with platinum catalysts, cobalt catalysts have lower costs, but their activity is slightly inferior. Therefore, they are more suitable for use in scenarios that are price-sensitive and have relatively moderate performance requirements.

Features Pros Disadvantages
Affordable Low initial investment cost Low activity may affect the performance of the final product
Fast curing speed Short processing time In some cases, it may cause premature aging of the material

3. Zinc catalyst

Zinc catalysts stand out for their environmentally friendly properties and low toxicity, and are widely used in food contact or medical-related fields. Although zinc-based catalysts are weak in activity, their good biocompatibility makes it an ideal choice.

Features Pros Disadvantages
Environmentally friendly No toxic side effects, suitable for sensitive areas Performance improvement is limited and not suitable for high-strength needs
Easy to process Strong material compatibility May need to be used in conjunction with other catalysts

4. Compound catalyst

For part-timeTaking into account the needs of different application scenarios, scientific researchers have developed a variety of composite catalysts. These catalysts achieve complementary performance by combining two or more metal components. For example, a platinum-cobalt composite catalyst can reduce overall costs while ensuring high activity, while a platinum-zinc composite catalyst can maintain environmentally friendly characteristics while meeting high performance requirements.

Features Pros Disadvantages
Diverency in functions Advantages of combining multiple catalysts The manufacturing process is complex and may increase costs
Customization enhancement Flexible adjustment of formula according to specific needs More experiments are needed to verify its long-term stability

Matching Analysis of Application Fields

Each type of polyurethane metal catalyst has its unique advantages and limitations, so the specific needs of the target application need to be fully considered when choosing. For example, in electric vehicle charging facilities, since the equipment is often exposed to outdoor environments, it is necessary to preferentially choose a catalyst type with strong weather resistance and high stability, such as a platinum-based catalyst or a composite catalyst. For non-critical components used indoors, cobalt-based catalysts or zinc-based catalysts with higher cost performance can be selected.

In short, the classification of polyurethane metal catalysts is not fixed, but can be flexibly adjusted according to actual needs. By rationally selecting and matching different catalyst types, their potential can be realized to a great extent and tailor-made solutions for various application scenarios.

The mechanism and functional characteristics of polyurethane metal catalyst

The mechanism of action of polyurethane metal catalysts can be explained by a series of complex chemical reactions that together form the basis of their outstanding functions. First, the metal ions in the catalyst enhance the overall structural stability of the material by promoting the crosslinking reaction between polyurethane molecules. This crosslinking process is similar to weaving a tight mesh, making the material more tough and durable and better resisting the erosion of external environmental factors.

Principle of chemical reaction

In the synthesis of polyurethane, the isocyanate group (-NCO) reacts with the polyol group (-OH) to form a carbamate bond (-NHCOO-). This reaction is a key step in the formation of polyurethane, while metal catalysts accelerate this process by reducing the reaction activation energy. Specifically, metal ions can adsorb on reactant molecules, changing their electricitysub-distribution, thus making the reaction more likely to occur. For example, platinum atoms in platinum-based catalysts can speed up the reaction rate by providing additional electrons to isocyanate molecules, lowering their reaction thresholds.

Functional Characteristics Analysis

1. Chemical corrosion resistance

Polyurethane metal catalysts significantly improve the chemical corrosion resistance of the material by strengthening intermolecular crosslinking. This means that even in an environment containing acid and alkali or other corrosive substances, the treated polyurethane material maintains its integrity and functionality. For example, in the cooling system of charging piles, the coolant may gradually corrode the inner wall of the pipe, and the use of a polyurethane coating containing platinum catalyst can effectively delay this process.

Test conditions Ordinary polyurethane Platinum-containing catalyst polyurethane
Immersion time (hours) 500 2000
Surface Status Obvious corrosion No significant change

2. Anti-UV Aging

Ultraviolet rays are one of the main causes of aging of plastic products, especially in charging facilities for outdoor use, materials exposed to sunlight for a long time are prone to discoloration, cracking and other problems. Polyurethane metal catalysts slow down the aging process of the material by absorbing and dispersing ultraviolet energy. For example, cobalt ions in cobalt-based catalysts can capture ultraviolet photons and convert them into thermal energy to release them, thereby protecting the material from damage.

Test conditions Ordinary polyurethane Polyurethane containing cobalt catalyst
Exposure time (day) 60 180
The degree of color change Sharp fading Slight fading

3. Thermal Stability

The charging facilities will generate a lot of heat during operation, especially high-power fast charging equipment, with internal temperatureThe degree may be as high as 100°C or above. Under such high temperature environments, the untreated polyurethane material is prone to soften or even deform. By introducing zinc-based catalysts, the glass transition temperature (Tg) of the material can be significantly improved so that it can still maintain its shape and performance at higher temperatures.

Test conditions Ordinary polyurethane Polyurethane, zinc-containing catalyst
Heating temperature (°C) 80 120
Material deformation Sharpened No significant change

To sum up, polyurethane metal catalysts impart a series of excellent functional characteristics to the material through a complex chemical reaction mechanism. These features not only improve the reliability of the charging facilities, but also extend their service life, providing users with a more stable and safe user experience.

Specific application of polyurethane metal catalysts in electric vehicle charging facilities

Polyurethane metal catalysts are widely used in electric vehicle charging facilities, covering almost every aspect from external structure to internal components. Below we will discuss in detail its specific application examples in charging pile shells, cable sheaths and cooling systems.

Charging pile shell: durable and beautiful

The charging pile shell is the first line of defense for charging facilities, directly bearing various challenges from the outside world, including ultraviolet radiation, wind and rain erosion and chemical pollution. Although traditional materials such as ordinary plastics or metals can provide some protection, they often suffer from aging, corrosion or appearance degradation during long-term use. The shell made of polyurethane material containing platinum catalyst shows excellent durability and aesthetics.

Performance Metrics Ordinary plastic shell Polla-containing catalyst polyurethane shell
Service life (years) 3-5 10-15
UV Anti-UV Index Medium High
Corrosion resistance grade Poor Outstanding

This material is not only able to effectively resist fading and brittlement caused by ultraviolet rays, but also resists the erosion of chemicals in rainwater and air, ensuring that the charging pile always remains bright as new. In addition, its good mechanical properties also make the shell less likely to be damaged when subjected to accidental impact, further improving the safety of the equipment.

Cable sheath: protecting core transmission lines

Cable sheath is a key component connecting charging piles to electric vehicles, and is responsible for protecting internal wires from the external environment. Although traditional rubber or PVC sheath is cheap, it is prone to cracking, hardening or softening under harsh conditions such as high temperature, low temperature and chemical corrosion, which affects the stability of power transmission. The use of polyurethane sheath containing cobalt catalyst solves these problems.

Performance Metrics Ordinary rubber sheath Polyurethane sheath with cobalt catalyst
Temperature range (°C) -20 to +60 -40 to +120
Flexibility retention rate 70% 95%
Chemical corrosion resistance General High

This new sheath material can maintain good flexibility and elasticity under extreme temperature conditions, avoiding breakage or deformation caused by temperature changes. At the same time, its excellent chemical corrosion resistance also enables the cable to maintain normal function for a long time when it comes into contact with harmful substances such as oil stains and salt spray.

Cooling system: Ensure efficient heat dissipation

With the development of fast charging technology, the heating capacity of charging facilities has increased significantly, and efficient cooling systems have become an indispensable part of ensuring the stable operation of the equipment. However, although traditional cooling pipe materials such as aluminum or copper have good thermal conductivity, they have problems such as weight and corrosion. The cooling pipe made of polyurethane composite material containing zinc catalyst has the advantages of lightweight and high corrosion resistance.

Performance Metrics Traditional metal pipes Polyurethane Pipeline with Zinc Catalyst
Weight (kg/m) 2.5 0.8
Corrosion resistance period 5 15
Thermal conductivity coefficient (W/m·K) 200 0.5

Although the thermal conductivity of polyurethane materials is lower than that of metals, its actual heat dissipation effect can fully meet the needs of modern charging facilities by optimizing the design and adding thermal fillers. More importantly, the lightweight properties of this material greatly reduce installation and transportation costs, while its excellent corrosion resistance also significantly extends the service life of the cooling system.

To sum up, the application of polyurethane metal catalysts in electric vehicle charging facilities not only improves the performance of each key component, but also provides strong guarantees for the long-term and stable operation of the entire system. Whether it is to resist the erosion of the external environment or adapt to the complex working conditions inside, this material has shown an incomparable advantage.

The current market status and development trend of polyurethane metal catalysts

As global focus on clean energy and sustainable development increases, polyurethane metal catalysts, as an innovative material, are gradually penetrating into electric vehicle charging facilities and other industrial fields. At present, the scale and technical level of the market are showing a trend of rapid expansion, and they are also facing some technical bottlenecks and development opportunities that need to be solved urgently.

Market Size and Growth Trend

According to statistics from international consulting agencies, as of 2022, the global polyurethane metal catalyst market size has reached about US$5 billion, and it is expected to continue to expand at a rate of average annual compound growth rate (CAGR) of more than 10% by 2030. This growth is mainly due to the following aspects:

  1. Policy promotion: Governments of various countries have successively introduced a series of policies to encourage the development of new energy vehicles, including subsidies, tax reductions and infrastructure construction support. These measures have greatly stimulated the demand for charging facilities and thus promoted the prosperity of the related material market.

  2. Market Demand: As electric vehicle sales continue to rise, the quantity and quality requirements of supporting charging facilities are also increasing. Especially in the construction of high-power fast charging stations, the demand for high-performance materials is particularly urgent, providing a broad application space for polyurethane metal catalysts.

  3. Technical Innovation: In recent years, scientific researchers have made significant progress in catalyst types, formulation optimization and production process improvement, further broadening their application scope and reducing production costs.

Year Market Size (US$ 100 million) Growth Rate (%)
2020 35 8
2021 40 14
2022 50 25
2023E 60 20

Technical Bottlenecks and Solutions

Although polyurethane metal catalysts show great development potential, there are still some technical bottlenecks that need to be overcome in practical applications:

1. Cost issue

Platinum-based catalysts are currently popular for their excellent performance, but their high prices limit their promotion in the low-end market. To address this problem, researchers are exploring more economically viable alternatives, such as reducing the amount of precious metals through nanotechnology, or developing efficient catalysts based on other metal elements.

2. Production process complexity

The preparation process of polyurethane metal catalyst involves multiple fine links, including uniform dispersion of metal particles, precise regulation of catalyst activity, etc. These processes require high technical level and equipment investment, which increases the entry threshold for enterprises. To this end, the industry is working hard to simplify the production process while strengthening standardization construction to reduce overall manufacturing costs.

3. Long-term stability test

Although laboratory data show that polyurethane metal catalysts have good durability, their long-term performance in actual use environments still needs further verification. Especially for performance assessments in extreme climate conditions, more large-scale field trials and data analysis are required.

Development prospects and prospects

Looking forward, polyurethane metal catalysts are expected to achieve breakthroughs in the following directions:

  1. MoreFunctional integration: By combining multiple catalysts, a composite material can be developed that can meet multiple performance needs at the same time. For example, a catalyst that has both high heat resistance and good flexibility will greatly enhance its scope of application.

  2. Intelligent upgrade: Combining sensor technology and IoT platform, polyurethane metal catalysts can be self-diagnosed and self-healed. This smart material can automatically trigger a repair mechanism when damage is detected, thus extending the service life of the device.

  3. Green development: With the increasing awareness of environmental protection, developing more environmentally friendly catalysts has become an inevitable trend. For example, the use of renewable resources to extract metal raw materials, or the treatment of waste materials through biodegradation technology will help achieve sustainable development of the industry.

In short, polyurethane metal catalysts are in a development stage full of opportunities and challenges. Through continuous technological innovation and market expansion, we have reason to believe that this material will play an increasingly important role in the energy revolution in the future.

Progress in domestic and foreign research and case analysis

Around the world, the research on polyurethane metal catalysts has attracted the attention of many top scientific research teams and has formed rich theoretical achievements and practical cases. The following will review the relevant research progress from both domestic and foreign levels, and demonstrate its practical application effect in electric vehicle charging facilities through typical cases.

Domestic research trends

In recent years, my country has made remarkable achievements in the field of polyurethane metal catalysts, especially in the exploration of basic theories and industrial application. A study from the School of Materials Science and Engineering of Tsinghua University shows that by introducing nano-scale platinum particles into polyurethane substrates, the heat resistance and oxidation resistance of the material can be greatly improved. Experimental data show that after the modified polyurethane material operated continuously at high temperature of 200°C for 1,000 hours, its mechanical properties declined by only 5%, far lower than that of traditional materials.

At the same time, the Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences focuses on the development of low-cost cobalt catalysts. They proposed a new “gradient doping” technology that significantly reduces raw material costs by forming a high-concentration cobalt ion layer on the surface of the material while maintaining a low concentration inside. This research result has been successfully applied to the manufacturing of charging pile shells of a well-known brand, greatly enhancing the market competitiveness of the product.

Research Institution Main Contributions Actually,Use
Tsinghua University Improving heat resistance Charging pile shell in high temperature environment
Ningbo Institute of Chinese Academy of Sciences Reduce costs Economic charging pile shell

Foreign research trends

Foreign scholars have also conducted a lot of groundbreaking research in the field of polyurethane metal catalysts. The Fraunhofer Institute for Material and Systems Research in Germany has developed an environmentally friendly polyurethane material based on zinc catalysts, which is specifically used in the fields of medical equipment and food packaging. However, this material has also proven to have potential value in electric vehicle charging facilities. For example, a European car company used the material in the cooling pipelines of its new charging piles, and the results showed that its corrosion resistance was nearly three times higher than that of traditional aluminum pipes.

The research team at the Massachusetts Institute of Technology (MIT) is committed to solving the long-term stability of polyurethane metal catalysts. They invented a “dynamic crosslinking” technology that builds a self-healing network structure inside the material, allowing it to automatically restore some of its performance after damage. This technology was applied to a high-power fast charging station project in North America. The results show that after five years of continuous operation, the performance decay rate of the equipment is only half that of ordinary materials.

Research Institution Main Contributions Practical Application
Germany Fraunhof Institute Environmental-friendly materials Cooling Pipe
Mr. Institute of Technology Self-repair technology High-power fast charging station

Typical Case Analysis

Case 1: A large charging station renovation project in Shanghai

Background: An old charging station located in the center of Shanghai has affected the user experience due to frequent equipment failures. After analysis, it was found that the main reason was that the materials of the charging pile shell and cable sheath were seriously aging.

Solution: Introduce polyurethane shell material with platinum catalyst and cable sheath material with cobalt catalyst forComprehensive upgrade. After the renovation is completed, the average service life of the equipment will be extended from the original 3 years to more than 10 years, and the user satisfaction will be significantly improved.

Case 2: Optimization of charging facilities in extremely cold areas in Norway

Background: The temperature in some parts of Norway can drop below -40°C in winter, and traditional charging facilities are difficult to adapt to such extreme environmental conditions.

Solution: Use zinc-containing catalyst-containing polyurethane composite material to make cooling pipes, and add antifreeze ingredients to the shell. The modified equipment can not only operate normally at low temperatures, but also exhibit excellent corrosion resistance, effectively reducing maintenance costs.

Through the above domestic and foreign research progress and case analysis, it can be seen that the application of polyurethane metal catalysts in electric vehicle charging facilities has moved from theoretical exploration to actual implementation, and has shown strong technological advantages and broad market prospects.

Future development direction and challenges of polyurethane metal catalysts

With the continuous advancement of technology and the growing market demand, polyurethane metal catalysts are full of unlimited possibilities and face many challenges in the future development path. These challenges mainly focus on three aspects: technological innovation, cost control and environmental protection.

The necessity of technological innovation

Although existing polyurethane metal catalysts have shown excellent performance, technological innovation is still an unavoidable topic to meet more complex application scenarios in the future. For example, driven by ultra-high-speed charging technology, the operating temperature of the charging facility will further increase, which puts higher requirements on the heat resistance and thermal conductivity of the material. Therefore, developing new catalysts that can operate stably at higher temperatures will become an important topic.

In addition, with the popularization of artificial intelligence and Internet of Things technology, charging facilities are gradually developing towards intelligence. This means that future polyurethane metal catalysts need not only have excellent physical and chemical properties, but also have to be able to seamlessly connect with other intelligent systems. For example, the state changes of the material are monitored through built-in sensors and feedback to the central control system in real time so that preventive measures can be taken in a timely manner.

Technical Requirements Existing Level Future goals
Heat resistance (°C) 120 >150
Thermal Conductivity (W/m·K) 0.5 >1.0
Level of intelligence First possession Complete integration

Pressure of cost control

High costs have always been one of the main obstacles to the widespread use of polyurethane metal catalysts. Although platinum-based catalysts are favored for their excellent performance, their prices are discouraged by many small and medium-sized manufacturers. Therefore, how to effectively reduce production costs while ensuring performance will be the key to future development.

On the one hand, it is possible to optimize the production process to reduce the use of precious metals and improve the utilization rate of materials; on the other hand, it is also possible to actively explore other cost-effective alternatives, such as developing efficient catalysts based on non-precious metals. In addition, large-scale production and standardized construction also help dilute unit costs, thereby further enhancing the market competitiveness of products.

Cost composition Current proportion Optimization Goals
Raw Materials 60% <50%
Production Technology 30% <25%
Other fees 10% Unchanged

Liability for environmental protection

With the increasing global environmental awareness, the research and development and application of any new material must take into account its impact on the ecological environment. Polyurethane metal catalysts are no exception. Currently, most catalyst production processes still rely on non-renewable resources and may produce a certain amount of waste. Therefore, it is particularly important to develop more environmentally friendly production processes and material systems.

For example, it may be attempted to extract metal raw materials from renewable resources or to process waste materials through biodegradation techniques to minimize damage to the natural environment. In addition, establishing a complete recycling and reuse mechanism is also one of the important ways to achieve sustainable development of the industry.

Environmental Protection Indicators Existing Level Future goals
Renewable Resource Ratio 20% >50%
Waste emissions Medium Extremely low
Recycling and Utilization Rate 30% >70%

In short, the future development of polyurethane metal catalysts cannot be separated from the coordinated promotion of three aspects: technological innovation, cost control and environmental protection. Only by ensuring superior performance while taking into account economic and sustainability can the widespread application of this innovative material be truly realized and contributed to the green energy transformation of human society.

Conclusion: The far-reaching significance and beautiful vision of polyurethane metal catalysts

Looking through the whole text, the application of polyurethane metal catalysts in electric vehicle charging facilities has shown its irreplaceable value. From basic theory to practical application, and then to future development directions, this innovative material not only provides a solid guarantee for the long-term stability of charging facilities, but also injects new vitality into the entire new energy vehicle industry.

The reflection of core values

The core value of polyurethane metal catalysts is that they can impart excellent functional characteristics to the material through complex chemical reaction mechanisms, thereby significantly improving the performance and service life of the charging facility. Whether it is resisting ultraviolet radiation, chemical corrosion, or adapting to extreme temperature conditions, this material has shown compelling performance. As an industry expert said: “Polyurethane metal catalysts are like putting a layer of ‘super armor’ on charging facilities, allowing it to deal with it calmly no matter what environment it is in.”

The significance of practical application

In practical applications, there are countless successful cases of polyurethane metal catalysts. From the upgrade and renovation of a large charging station in Shanghai to the optimization of charging facilities in extremely cold areas of Norway, every successful practice proves the strong strength of this material. It not only solves the shortcomings of traditional materials in terms of durability, stability and environmental protection, but also brings users a more convenient and reliable charging experience.

A beautiful vision for future prospects

Looking forward, the development prospects of polyurethane metal catalysts are bright. With the continuous advancement of technology, we can expect more efficient, economical and environmentally friendly catalysts to be released. By then, both fast charging stations in the city center and slow charging piles in remote areas will become more durable and smart due to the existence of this material.

More importantly, the application of polyurethane metal catalysts is not limited to the field of electric vehicle charging facilities. Its potential can extend to multiple industries such as aerospace, medical equipment, construction and building materials, and provide strong support for the sustainable development of human society. Just as the old sayingHe said, “If you want to do a good job, you must first sharpen your tools.” Polyurethane metal catalysts are such powerful tools that pave the way for our green energy future.

Extended reading:https://www.cyclohexylamine.net/high-quality-n-dimethylaminopropyldiisopropanolamine-cas-63469-23-8-n-3-dimethyl-amino-propyl-n-n-diisopropanolamine/

Extended reading:https://www.bdmaee.net/fentacat-10-catalyst-cas100-42-5-solvay/

Extended reading:https://www.cyclohexylamine.net/delayed-catalyst-1028-delayed-catalyst/

Extended reading:https://www.newtopchem.com/archives/40552

Extended reading:https://www.bdmaee.net/lupragen-n301-catalyst-pentalyst-pentalyst-for-soles/

Extended reading:https://www.cyclohexylamine.net/catalyst-25-s-catalyst-for-soles/

Extended reading:https://www.newtopchem.com/archives/1677

Extended reading:https://www.bdmaee.net/pc-cat-tka-metal-carboxylate-catalyst-nitro/

Extended reading:https://www.newtopchem.com/archives/category/products/page/144

Extended reading:https://www.bdmaee.net/wp-content/uploads/2019/10/1-2.jpg

1•975976977978979•2238
Page 977 of 2238