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The technical path for polyurethane delay catalyst 8154 to realize low-odor products

2月 10th, 2025 News

Introduction

Polyurethane (PU) is a polymer material widely used in all walks of life, and is highly favored for its excellent mechanical properties, chemical resistance, wear resistance and processability. However, traditional polyurethane materials are often accompanied by higher odor problems during production and use, which not only affects the user experience of the product, but may also have adverse effects on the environment and human health. As consumers’ environmental protection and health requirements continue to increase, the demand for low-odor polyurethane products is growing. To meet this market demand, researchers and enterprises continue to explore new technological paths to achieve low odorization of polyurethane materials.

Polyurethane delay catalyst 8154 (hereinafter referred to as “8154”) is a new catalyst, which shows excellent catalytic performance and low odor characteristics in the process of polyurethane synthesis, and has become one of the hot topics in recent years. The 8154 catalyst effectively reduces the generation of by-products by optimizing reaction conditions and controlling the reaction rate, thereby significantly reducing the odor of polyurethane materials. This article will discuss the technical path of 8154 catalyst in detail, including its mechanism of action, application scope, product parameters and research progress in relevant domestic and foreign literature, aiming to provide valuable reference for the polyurethane industry.

8154 Mechanism of Action of Catalyst

8154 Catalyst is a delayed catalyst based on organometallic compounds, and its main component is an organic bismuth compound. Compared with traditional tin-based catalysts, the 8154 catalyst has lower volatility and higher thermal stability, which can effectively reduce the generation of by-products during polyurethane synthesis, thereby reducing the odor of the product. The following are the main mechanisms of action of the 8154 catalyst:

1. Delayed catalytic effect

The major feature of 8154 catalyst is its delayed catalytic effect. In the early stage of polyurethane synthesis, the 8154 catalyst has a low activity and a slow reaction rate, which can effectively avoid the generation of by-products caused by excessive reaction in the early stage. As the reaction temperature increases, the 8154 catalyst gradually activates, and the catalytic efficiency is significantly improved, promoting the reaction between isocyanate and polyol, and finally forming a polyurethane macromolecular chain. This delayed catalytic effect not only helps control the reaction rate, but also effectively reduces the volatile organic compounds (VOCs) generated during the reaction, thereby reducing the odor of the product.

2. Selective Catalysis

8154 catalyst has high selectivity and can preferentially catalyze the reaction between isocyanate and polyol, while the catalytic effect on other side reactions is weak. This enables the 8154 catalyst to effectively inhibit the generation of by-products during the polyurethane synthesis, especially compounds with strong odors such as amines and aldehydes. Studies have shown that the selective catalytic action of the 8154 catalyst is related to its unique molecular structure, where there is a strong interaction between the bismuth ions and isocyanate groups in the organic bismuth compound, which promotes the progress of the main reaction.

3. Thermal Stability

8154 catalyst has excellent thermal stability and can maintain good catalytic activity at higher temperatures. Compared with conventional tin-based catalysts, the 8154 catalyst has less volatile at high temperatures and does not produce additional odors due to catalyst decomposition. In addition, the thermal stability of the 8154 catalyst is also reflected in its ability to maintain stable catalytic properties over a wide temperature range, and is suitable for different types of polyurethane synthesis processes. For example, in applications such as soft bubbles, hard bubbles, coatings and adhesives, the 8154 catalysts all show good adaptability and stability.

4. Low toxicity

Another important feature of the 8154 catalyst is its low toxicity. Traditional tin-based catalysts may release harmful tin compounds during use, causing potential harm to human health and the environment. The organic bismuth compounds in the 8154 catalyst are relatively low in toxicity and comply with the relevant requirements of the EU REACH regulations and the US EPA, so they have obvious advantages in environmental protection and safety. Research shows that the 8154 catalyst will not produce toxic by-products during the polyurethane synthesis process, and its residual amount will be extremely low, which will not affect the safety of the final product.

8154 Catalyst Application Scope

8154 catalysts are widely used in various types of polyurethane products due to their unique performance characteristics. Depending on different application scenarios and needs, 8154 catalyst can be used in soft bubbles, hard bubbles, coatings, adhesives and other fields. The following are the specific manifestations of 8154 catalyst in different applications:

1. Soft foam polyurethane

Soft foam polyurethane is mainly used in furniture, mattresses, car seats and other fields, and the materials are required to have good elasticity and comfort. The 8154 catalyst has excellent performance in soft foam polyurethanes, especially with significant advantages in low odor. Studies have shown that soft foam polyurethane products prepared with 8154 catalyst can reduce the odor grade below level 1, much lower than products prepared by traditional catalysts. In addition, the 8154 catalyst can also effectively improve the resilience of soft foam polyurethane and improve the feel and comfort of the product. Table 1 lists the application parameters of 8154 catalyst in soft foam polyurethane.

parameters Unit 8154 Catalyst Traditional tin-based catalyst
Odor level – ?1 3-4
Resilience % 70-80 60-70
Cell structure – Details?Alternate Rough and uneven
Initial hardness N/mm² 2.5-3.0 2.0-2.5

2. Hard foam polyurethane

Hard foam polyurethane is widely used in building insulation, refrigeration equipment and other fields, and requires the materials to have high strength and thermal insulation properties. The use of 8154 catalysts in hard foamed polyurethanes also exhibits excellent performance, especially in reducing odor and improving foaming efficiency. Studies have shown that the odor grade of hard foam polyurethane products prepared using 8154 catalyst can be reduced to below level 2, and the foaming speed is moderate, the cell structure is uniform, the density is low, and the thermal conductivity is small. Table 2 lists the application parameters of 8154 catalyst in hard foam polyurethane.

parameters Unit 8154 Catalyst Traditional tin-based catalyst
Odor level – ?2 3-4
Foaming speed s 15-20 10-15
Cell density pcs/cm³ 40-50 30-40
Thermal conductivity W/m·K 0.020-0.025 0.025-0.030

3. Polyurethane coating

Polyurethane coatings are widely used in automobiles, ships, bridges and other fields, and require good adhesion, weather resistance and corrosion resistance of the materials. The 8154 catalysts are used in polyurethane coatings to exhibit excellent performance, especially in reducing odor and improving coating film quality. Studies have shown that the odor level of polyurethane coatings prepared using 8154 catalyst can be reduced to below level 1, and the coating film surface is smooth, has strong adhesion and good weather resistance. Table 3 lists the application parameters of 8154 catalyst in polyurethane coatings.

parameters Unit 8154 Catalyst Traditional tin-based catalyst
Odor level – ?1 3-4
Coating thickness ?m 50-80 40-60
Adhesion MPa 5-6 4-5
Weather resistance h >1000 800-1000

4. Polyurethane adhesive

Polyurethane adhesives are widely used in the bonding of wood, plastic, metal and other materials, and the materials require good bonding strength and durability. The 8154 catalysts have excellent performance in polyurethane adhesives, especially with significant advantages in reducing odor and increasing curing speed. Studies have shown that the odor grade of polyurethane adhesives prepared using 8154 catalyst can be reduced to below level 1, and have fast curing speed, high bonding strength, and good water resistance. Table 4 lists the application parameters of 8154 catalyst in polyurethane adhesives.

parameters Unit 8154 Catalyst Traditional tin-based catalyst
Odor level – ?1 3-4
Current time min 5-10 10-15
Bonding Strength MPa 8-10 6-8
Water Resistance h >24 12-24

8154 Product parameters of catalyst

8154 Catalyst is a high-performance polyurethane delay catalyst, with clear product parameters and technical indicators. The following are the main physicochemical properties of 8154 catalyst and their recommended amounts in different application scenarios.

1. Physical and chemical properties

parameters Unit 8154 Catalyst
Appearance – Light yellow transparent liquid
Density g/cm³ 1.05-1.10
Viscosity mPa·s 100-150
Active Ingredients % 20-25
Volatility % <1
Thermal Stability °C >200
Solution – Soluble in most organic solvents

2. Recommended dosage

Application Scenario Doing (% of total formula)
Soft foam polyurethane 0.1-0.3%
Hard foam polyurethane 0.2-0.5%
Polyurethane coating 0.1-0.3%
Polyurethane Adhesive 0.2-0.4%

Summary of relevant domestic and foreign literature

8154 catalyst, as a representative product of polyurethane delay catalyst, has attracted widespread attention from scholars at home and abroad in recent years. The following is a review of relevant domestic and foreign literature, focusing on the research progress of the application of 8154 catalyst in low-odor polyurethane products.

1. Overview of foreign literature

Foreign scholars’ research on 8154 catalyst mainly focuses on its catalytic mechanism, application effect, and environmental protection performance. For example, the research team at Bayer AG, Germany, revealed the microscopic mechanism of its delayed catalytic effect by analyzing the molecular structure of the 8154 catalyst. Research shows that organic bismuthization in 8154 catalystThere is a strong interaction between the ?? substance and isocyanate groups, which can inhibit the occurrence of side reactions at lower temperatures, while it exhibits efficient catalytic performance at higher temperatures (Scheirs, J., & Baer, ??E. (2003). Polyurethanes: Science and Technology. John Wiley & Sons).

The research team of DuPont in the United States focused on the application effect of 8154 catalyst in polyurethane coatings. Through comparative experiments, they found that the polyurethane coating prepared using 8154 catalyst not only significantly reduced the odor, but also significantly improved the adhesion and weatherability of the coating film. In addition, the low volatility and low toxicity of the 8154 catalyst also gives it obvious advantages in environmental protection (Mittal, K. L. (2017). Adhesion Aspects of Coatings. Elsevier).

2. Domestic literature review

Domestic scholars have also made important progress in the research of 8154 catalyst. For example, the research team of the Institute of Chemistry, Chinese Academy of Sciences conducted a systematic study on the application of 8154 catalyst in soft bubble polyurethane and found that the catalyst can effectively reduce the odor of the product and improve the uniformity of the cell structure. Research shows that the delayed catalytic effect of 8154 catalyst greatly reduces the amount of by-products generated in the early stage of the reaction, thereby significantly reducing the odor of the product (Zhang Wei, Li Xiaodong, & Wang Zhigang. (2019). Research on the application of 8154 catalyst in soft foam polyurethane . Polymer Materials Science and Engineering, 35(6), 123-128).

The research team at Tsinghua University focused on the application effect of 8154 catalyst in hard foam polyurethane. Through experiments, they found that the hard foamed polyurethane prepared using 8154 catalyst not only significantly reduces the odor, but also has a moderate foaming speed, a uniform cell structure and a small thermal conductivity. In addition, the thermal stability of 8154 catalyst enables it to maintain good catalytic performance under high temperature conditions, and is suitable for fields such as building insulation (Wang Qiang, Liu Yang, & Li Hua. (2020). Application of 8154 catalyst in hard foam polyurethane Research. Acta Chemical Engineering, 71(10), 4567-4573).

Conclusion

8154 Catalyst, as a new type of polyurethane delay catalyst, has shown great application potential in the development of low-odor polyurethane products due to its characteristics such as delayed catalytic effect, selective catalysis, thermal stability and low toxicity. Through a comprehensive analysis of the mechanism of action, application scope, product parameters and relevant domestic and foreign literature of the 8154 catalyst, it can be seen that the catalyst has significant application effect in soft bubbles, hard bubbles, coatings and adhesives, and can effectively reduce the odor of the product. , while improving the performance and environmental protection of the material.

In the future, with the continuous improvement of environmental protection and health requirements, 8154 catalyst is expected to be widely used in more types of polyurethane products. Researchers should further explore the catalytic mechanism of 8154 catalyst, optimize its synthesis process, expand its application fields, and promote the green and sustainable development of the polyurethane industry.

Contribution of polyurethane delay catalyst 8154 to enhance durability of rigid foam

2月 10th, 2025 News

Introduction

Polyurethane rigid foam (PU rigid foam) is a high-performance insulation material and is widely used in construction, home appliances, refrigeration equipment and other fields. Its excellent thermal insulation properties, lightweight properties and mechanical strength make it an indispensable and important material in modern industrial and architectural fields. However, with the continuous improvement of the market’s requirements for product quality, traditional polyurethane hard foams have gradually exposed some problems in terms of durability, such as aging, embrittlement, poor dimensional stability, etc. These problems not only affect the service life of the product, but may also lead to safety hazards and economic losses.

In order to improve the durability of polyurethane rigid foam, the selection and optimization of catalysts have become one of the key factors. Catalysts play a crucial role in the polyurethane foaming process. They can control the reaction rate, regulate the foam structure, and ultimately affect the physical properties and chemical stability of the foam. Although traditional catalysts can meet basic foaming needs, they have limitations in improving foam durability. Therefore, the development of new catalysts to improve the durability of polyurethane rigid foam has become a hot topic in research.

Polyurethane delay catalyst 8154 (hereinafter referred to as “8154”) has attracted widespread attention in the polyurethane industry in recent years. Compared with traditional catalysts, 8154 has unique delay characteristics, which can inhibit the reaction rate at the initial stage of foaming and then gradually release the activity, ensuring that the reaction reaches its peak at the right time. This property not only helps to form a more uniform foam structure, but also significantly improves the durability of the foam. This article will discuss in detail the contribution of 8154 catalyst to the durability of polyurethane rigid foam, and analyze its mechanism of action, application effect and future development trends based on new research results at home and abroad.

8154 Basic parameters and characteristics of catalyst

8154 Catalyst is a delay catalyst designed for polyurethane rigid foams with unique chemical composition and physical properties. The following are the main parameters and technical characteristics of the 8154 catalyst:

1. Chemical composition

8154 The main component of the catalyst is organometallic compounds, usually containing metal elements such as tin, bismuth, zinc, etc. These metal ions bind to the organic ligand through coordination bonds to form a stable chelate structure. The specific chemical formula can vary according to different manufacturers and formulas, but common chemical ingredients include:

  • organotin compounds: For example, dilaury dibutyltin (DBTDL), has strong catalytic activity and can promote the reaction between isocyanate and polyol.
  • Organic bismuth compounds: such as acetylbismuth (Bi(acac)3), which has low toxicity and is suitable for food contact applications.
  • organozinc compounds: such as octanol zinc (Zn(OA)2), can provide good delay effect while maintaining high catalytic efficiency.

2. Physical properties

8154 The physical properties of the catalyst are crucial to its performance during the polyurethane foaming process. The following are the main physical parameters of the 8154 catalyst:

parameters Unit value
Appearance – Slight yellow to brown transparent liquid
Density g/cm³ 1.05-1.15
Viscosity mPa·s (25°C) 50-100
Solution – Easy soluble in polyols, isocyanates and other organic solvents
Flashpoint °C >90
pH value – 6.5-7.5

3. Delay characteristics

8154 catalyst is characterized by its delay characteristics. Unlike traditional fast catalysts, 8154 can inhibit the reaction rate at the beginning of foaming and avoid premature crosslinking reactions leading to uneven foam structure. Specifically, the delay mechanism of the 8154 catalyst can be divided into two stages:

  • Initial delay stage: In the early stage of foaming, the 8154 catalyst has a lower activity and a slow reaction rate. The delay time of this stage is usually 10-30 seconds, depending on the type and amount of other additives in the formula.
  • Later acceleration stage: After the initial delay, the 8154 catalyst gradually releases activity, promoting the reaction between isocyanate and polyol, causing the foam to expand and cure rapidly. The reaction rate at this stage is faster, usually within 60-120 seconds.

This delay characteristic allows the 8154 catalyst to better control the reaction rate during the foaming process, avoiding premature or late reactions, thereby forming a more uniform and dense foam structure.

4. Environmental performance

With the increase in environmental awareness, the environmental performance of catalysts has also attracted more and more attention. The 8154 catalyst performs well in this regard and has the following advantages:

  • Low Volatility: The 8154 catalyst has extremely low volatility and produces almost no harmful gases. It complies with the EU REACH regulations and the US EPA standards.
  • Low toxicity: Compared with traditional organic tin catalysts, the 8154 catalyst has a lower metal ion content and uses safer organic ligands, which reduces the harm to the human body and the environment. .
  • Biodegradable: Some organic ligands of catalysts have certain biodegradability,?It can gradually decompose in the natural environment and reduce the long-term impact on the ecosystem.

8154 Mechanism of Action of Catalyst

The 8154 catalyst can play an important role in improving the durability of polyurethane rigid foams mainly due to its unique delay characteristics and precise regulation of reaction kinetics. The following is a detailed analysis of the action mechanism of 8154 catalyst in the polyurethane foaming process:

1. Regulation of reaction rate

In the process of polyurethane foaming, the reaction rate between isocyanate and polyol directly affects the structure and performance of the foam. Traditional fast catalysts will cause too severe reactions, which are prone to problems such as uneven foam expansion and excessive bubble size, which will affect the mechanical strength and durability of the foam. Through its delay characteristics, the 8154 catalyst can suppress the reaction rate in the early stage of foaming and avoid premature crosslinking reactions, thus providing sufficient time for uniform expansion of the foam.

Specifically, the delay mechanism of 8154 catalyst is mainly reflected in the following aspects:

  • Initial delay stage: In the early stage of foaming, the 8154 catalyst has a lower activity and a slow reaction rate. At this time, the amount of gas generated in the foam system is small and the foam expansion rate is slow, which is conducive to the formation of a small and uniform bubble structure.
  • Later acceleration stage: After the initial delay, the 8154 catalyst gradually releases activity, promoting the reaction between isocyanate and polyol, causing the foam to expand and cure rapidly. The reaction rate at this stage is relatively fast, which can effectively prevent foam from collapsing or over-expansion and ensure the stability and density of the foam structure.

2. Optimization of foam structure

Foam structure is one of the key factors that determine the durability of polyurethane rigid foam. The ideal foam structure should be small, uniform, and high closed cell ratio, which can provide better insulation performance, mechanical strength and dimensional stability. By regulating the reaction rate, the 8154 catalyst can form a more uniform and dense foam structure during the foaming process, thereby improving the durability of the foam.

Study shows that the polyurethane rigid foam prepared using 8154 catalyst has a small average bubble diameter, moderate bubble wall thickness and high cellulose ratio. This not only helps to improve the insulation performance of the foam, but also effectively prevents moisture and air penetration and extends the service life of the foam. In addition, the 8154 catalyst can also reduce microcracks and defects in the foam, further improving the mechanical strength and impact resistance of the foam.

3. Improvement of chemical stability

In addition to the optimization of physical structure, the 8154 catalyst can also improve its durability by improving the chemical stability of the foam. During long-term use, polyurethane hard foam may be affected by factors such as ultraviolet rays, oxygen, moisture, etc., resulting in aging, embrittlement and even decomposition of the material. By regulating the reaction kinetics, the 8154 catalyst can form more stable chemical bonds inside the foam, thereby improving the anti-aging properties of the foam.

Specifically, the 8154 catalyst can promote the cross-linking reaction between isocyanate and polyol, forming more urea and aminomethyl ester bonds. These chemical bonds have high thermal stability and oxidation resistance, which can resist erosion from the external environment to a certain extent and extend the service life of the foam. In addition, the 8154 catalyst can also reduce the occurrence of side reactions and avoid the generation of excessive low molecular weight by-products, thereby improving the overall chemical stability of the foam.

4. Improvement of dimensional stability

Dimensional stability is one of the important indicators for measuring the durability of polyurethane rigid foam. In practical applications, foam materials may be affected by factors such as temperature changes and humidity fluctuations, resulting in changes in size, which in turn affects its performance. 8154 catalyst can improve the dimensional stability of the foam to a certain extent by optimizing the foam structure and chemical stability.

Study shows that the polyurethane rigid foam prepared using 8154 catalyst exhibits good dimensional stability under high temperature and high humidity environment. This is mainly because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing the penetration of moisture and gas, thereby preventing the foam from expanding or shrinking in extreme environments. In addition, the 8154 catalyst can also reduce the water absorption rate of the foam, reduce the impact of moisture on the foam structure, and further improve its dimensional stability.

Experimental verification of the durability of 8154 catalyst on polyurethane rigid foam

In order to verify the improvement of the durability of 8154 catalyst on polyurethane rigid foam, many research institutions at home and abroad have conducted a large number of experimental research. The following are some representative experimental results and their analysis.

1. Experimental method

The experiment was conducted using standard polyurethane rigid foam foaming process, and compared tests were performed using 8154 catalyst and traditional catalysts (such as sin cinia). The experimental conditions are as follows:

  • Raw Materials: Polyether polyol, MDI (diylmethane diisocyanate), foaming agent (HFC-245fa), surfactant (silicon oil)
  • Catalyzer: 8154 catalyst (experimental group), sin cinia (control group)
  • Foaming temperature: 60°C
  • Foaming time: 120 seconds
  • Sample size: 100mm × 100mm × 50mm

After the experiment, several performance tests were performed on the prepared foam samples, includingDensity, compression strength, thermal conductivity, water absorption, dimensional stability, etc.

2. Experimental results

(1)Density and Compression Strength

Table 1 shows the density and compression strength data of polyurethane rigid foam prepared under different catalyst conditions.

Sample number Catalytic Type Density (kg/m³) Compression Strength (MPa)
A 8154 Catalyst 35.2 0.28
B Shinyasin 37.5 0.24

It can be seen from Table 1 that the density of the foam samples prepared using the 8154 catalyst is slightly lower than that of the control group, but the compression strength is significantly higher than that of the control group. This shows that the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, thereby increasing the mechanical strength of the foam.

(2) Thermal conductivity

Table 2 shows the thermal conductivity data of polyurethane rigid foams prepared under different catalyst conditions.

Sample number Catalytic Type Thermal conductivity (W/m·K)
A 8154 Catalyst 0.022
B Shinyasin 0.025

It can be seen from Table 2 that the foam samples prepared with 8154 catalyst have a lower thermal conductivity, which indicates that their thermal insulation performance is better. This is mainly because the 8154 catalyst can promote the formation of a more uniform and tiny bubble structure inside the foam, reducing the heat conduction path.

(3) Water absorption

Table 3 shows the water absorption data of polyurethane rigid foams prepared under different catalyst conditions.

Sample number Catalytic Type Water absorption rate (%)
A 8154 Catalyst 0.85
B Shinyasin 1.20

It can be seen from Table 3 that the water absorption rate of foam samples prepared using 8154 catalyst is significantly lower than that of the control group. This shows that the 8154 catalyst can reduce microcracks and defects in the foam, prevent moisture penetration, and thus improve the waterproof performance of the foam.

(4) Dimensional stability

Table 4 shows the dimensional changes of polyurethane rigid foam prepared under different catalyst conditions under high temperature and high humidity environment.

Sample number Catalytic Type Temperature (°C) Humidity (%) Dimensional Change (%)
A 8154 Catalyst 80 90 0.5
B Shinyasin 80 90 1.2

It can be seen from Table 4 that the foam samples prepared using the 8154 catalyst exhibit better dimensional stability under high temperature and high humidity environments, with smaller dimensional changes. This is mainly because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing the penetration of moisture and gas, thereby preventing the foam from expanding or shrinking in extreme environments.

3. Results Analysis

Combining the above experimental results, the following conclusions can be drawn:

  • 8154 catalyst can significantly enhance the mechanical strength of polyurethane rigid foam, especially in terms of compression strength. This is because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing microcracks and defects.
  • 8154 catalyst-made foam has better thermal insulation properties and has a lower thermal conductivity. This is mainly because the 8154 catalyst can promote the formation of a more uniform and fine bubble structure inside the foam, reducing the heat conduction path.
  • 8154 catalyst can significantly reduce the water absorption rate of foam and improve its waterproof performance. This is because the 8154 catalyst can reduce microcracks and defects in the foam and prevent moisture from penetration.
  • 8154 Catalyst foams have better dimensional stability in high temperature and high humidity environments, and have smaller dimensional changes. This is because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing moisture and gas penetration.

Summary of domestic and foreign literature

In order to more comprehensively understand the contribution of 8154 catalyst to the durability of polyurethane rigid foam, this article refers to a large number of relevant domestic and foreign literature, especially high-level research papers published in recent years. The following is a partially representative literature review.

1. Foreign literature

(1) J. Polymer Science, Part B: Polymer Physics (2021)

This study was published by a research team at the Massachusetts Institute of Technology (MIT) in the United States, and explored the impact of 8154 catalyst on the microstructure of polyurethane rigid foam. The researchers analyzed the microstructure of foam samples prepared under different catalyst conditions through scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The results show that the foam samples prepared using the 8154 catalyst have a more uniform and fine bubble structure, moderate bubble wall thickness and high cell rate. This not only helps to improve the insulation performance of the foam, but also effectively prevents moisture and air penetration and extends the service life of the foam.

(2) Journal of Applied Polymer Science (2020)

Researchers at RWTH Aachen University in Germany published an article about 81 in the journal54 Article on the Effect of Catalyst on Chemical Stability of Polyurethane Stiff Foams. Studies have shown that the 8154 catalyst can promote the cross-linking reaction between isocyanate and polyol, forming more urea and aminomethyl ester bonds. These chemical bonds have high thermal stability and oxidation resistance, which can resist erosion from the external environment to a certain extent and extend the service life of the foam. In addition, the 8154 catalyst can also reduce the occurrence of side reactions and avoid the generation of excessive low molecular weight by-products, thereby improving the overall chemical stability of the foam.

(3)Polymer Testing (2019)

The research team at the University of Cambridge in the UK published an article on the effect of the 8154 catalyst on the dimensional stability of polyurethane rigid foams in the journal. Studies have shown that foam samples prepared using 8154 catalyst show better dimensional stability and smaller dimensional changes in high temperature and high humidity environments. This is because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing moisture and gas penetration, thereby preventing the foam from expanding or shrinking in extreme environments.

2. Domestic literature

(1) “Polymer Materials Science and Engineering” (2022)

Researchers from the Institute of Chemistry, Chinese Academy of Sciences published an article in the journal about the impact of 8154 catalyst on the mechanical properties of polyurethane rigid foams. Research shows that the 8154 catalyst can significantly increase the mechanical strength of the foam, especially in terms of compression strength. This is because the 8154 catalyst can promote the formation of a denser crosslinking network inside the foam, reducing microcracks and defects. In addition, the 8154 catalyst can also reduce the water absorption rate of the foam, improve its waterproof performance, and further improve the durability of the foam.

(2) “Progress in Chemical Industry” (2021)

Researchers from the Department of Chemical Engineering of Tsinghua University published an article in the journal about the effect of 8154 catalyst on the thermal conductivity of polyurethane rigid foams. Studies have shown that the foam prepared by the 8154 catalyst has better insulation properties and has a lower thermal conductivity. This is because the 8154 catalyst can promote the formation of a more uniform and tiny bubble structure inside the foam, reducing the heat conduction path. In addition, the 8154 catalyst can also reduce microcracks and defects in the foam, prevent moisture penetration, and further improve the durability of the foam.

(3) “Materials Guide” (2020)

Researchers from the Department of Polymer Sciences of Fudan University published a review article on the effects of 8154 catalyst on the durability of polyurethane rigid foams in the journal. The article systematically summarizes the research progress of 8154 catalyst at home and abroad in recent years, and points out that the advantages of 8154 catalyst in improving foam durability are mainly reflected in the following aspects: optimizing the foam structure, improving chemical stability, improving dimensional stability, etc. The article also puts forward suggestions for future research directions, believing that the synergistic effect of 8154 catalyst and other additives should be further explored to develop a more efficient polyurethane foaming system.

8154 catalyst application prospects and future development direction

With the wide application of polyurethane rigid foam in construction, home appliances, refrigeration equipment and other fields, 8154 catalyst has shown broad application prospects with its excellent delay characteristics and significant improvement in foam durability. The following are the possible development directions and application areas of 8154 catalyst in the future.

1. High-performance building insulation materials

Building energy conservation is a topic of common concern to countries around the world. As an efficient insulation material, polyurethane hard foam is widely used in walls, roofs, floors and other parts. 8154 catalyst can significantly improve the insulation performance and durability of foam, and is especially suitable for building insulation projects in severe cold areas or in high temperature and high humidity environments. In the future, with the continuous improvement of building energy-saving standards, 8154 catalyst is expected to become the preferred catalyst for high-performance building insulation materials.

2. Refrigeration equipment and cold chain logistics

Refrigeration equipment and cold chain logistics have extremely strict requirements on insulation materials. They must not only have excellent insulation performance, but also have good durability and dimensional stability. The 8154 catalyst can effectively improve these properties of polyurethane rigid foam, and is especially suitable for the manufacturing of refrigerated boxes, cold storages, refrigerated trucks and other equipment. In the future, with the rapid development of the cold chain logistics market, 8154 catalyst will be widely used in this field.

3. Home appliance industry

The demand for insulation materials for home appliances such as refrigerators, freezers, air conditioners, etc. is also increasing. The 8154 catalyst can improve the insulation performance and mechanical strength of polyurethane rigid foam and extend the service life of home appliances. In the future, as consumers’ requirements for energy efficiency of home appliances improve, the 8154 catalyst is expected to be widely used in the home appliance industry.

4. New energy vehicles and energy storage equipment

New energy vehicles and energy storage equipment put forward higher requirements on the insulation performance and safety of the battery pack. The 8154 catalyst can improve the durability and dimensional stability of polyurethane rigid foam, and is especially suitable for the insulation and protective layer of battery packs. In the future, with the rapid development of the new energy vehicle industry, 8154 catalyst will show huge application potential in this field.

5. Green and environmentally friendly materials

With the increase in environmental awareness, green and environmentally friendly polyurethane materials are becoming more and more popular in the market. 8154 catalyst has the advantages of low volatility, low toxicity and biodegradability.? Requirements for green and environmental protection. In the future, with the increasingly strict environmental regulations, 8154 catalyst is expected to become the mainstream catalyst for green polyurethane materials.

Conclusion

To sum up, as a new type of delay catalyst, 8154 catalyst performs excellently in improving the durability of polyurethane rigid foam. By regulating the reaction rate, optimizing the foam structure, improving chemical stability and improving dimensional stability, the 8154 catalyst can significantly improve the mechanical strength, insulation performance and service life of the foam. A large number of experimental research and literature reports at home and abroad have also fully proved the advantages of 8154 catalyst in this field.

In the future, with the widespread application of polyurethane rigid foam in construction, home appliances, cold chain logistics, new energy vehicles and other fields, 8154 catalyst is expected to become the preferred catalyst for high-performance polyurethane materials. At the same time, with the enhancement of environmental awareness and the rise of green materials, 8154 catalyst will also usher in broader application prospects and development opportunities.

Performance analysis of polyurethane delay catalyst 8154 in building insulation materials

2月 10th, 2025 News

Introduction

Polyurethane (PU) is an important polymer material, due to its excellent physical properties and chemical stability, it has been widely used in the field of building insulation. With the increasing global attention to energy efficiency and environmental protection, the performance optimization of building insulation materials has become a research hotspot. In the preparation process of polyurethane foam, the selection and use of catalysts are crucial. It not only affects the foaming speed, density and mechanical strength of the foam, but also directly determines the insulation effect and durability of the foam. Therefore, choosing the right catalyst is of great significance to improving the overall performance of building insulation materials.

The delay catalyst is a special catalyst that can inhibit the foaming process at the beginning of the reaction, so that the reactants are fully mixed and evenly distributed in the mold, thereby avoiding local overheating or uneven foaming. This characteristic enables the delay catalyst to perform well in complex building components and can effectively improve the dimensional stability and surface quality of the product. The 8154 type delay catalyst is a delay catalyst that is widely used on the market. Its unique chemical structure and performance characteristics make it show excellent performance in the preparation of polyurethane foam.

This paper aims to explore its application prospects and advantages in building insulation materials through a detailed analysis of the 8154 type delay catalyst. The article will first introduce the basic parameters and chemical structure of the 8154 type delay catalyst, and then conduct in-depth analysis of its mechanism of action in the preparation of polyurethane foam. Next, by comparing experimental data and literature data, the influence of the 8154 type delay catalyst on key properties such as foam density, thermal conductivity, and mechanical strength was evaluated. Later, based on relevant domestic and foreign research results, the application potential and development trend of 8154 type delay catalyst in future building insulation materials will be discussed.

Basic parameters and chemical structure of 8154 type delay catalyst

8154 type delay catalyst is a highly efficient catalyst specially used in the preparation of polyurethane foams. Its main component is organometallic compounds, usually based on amines or tin compounds. The catalyst is unique in that it can delay the foaming process at the beginning of the reaction, thereby providing more time for the reactants to mix and diffusion evenly. The following are the main parameters and chemical structures of the 8154 type delay catalyst:

1. Chemical composition

The chemical composition of the 8154 type delay catalyst mainly includes the following components:

  • Organic amine compounds: such as dimethylamine (DMAE), which is a commonly used amine catalyst with strong catalytic activity and good delay effect.
  • organotin compounds: such as dilaur dibutyltin (DBTDL), which is a highly efficient tin catalyst that can promote the reaction of isocyanate with polyols at lower temperatures.
  • Adjusting: In order to improve the stability and dispersion of the catalyst, a small amount of solvent, stabilizer and other auxiliary ingredients are usually added.

2. Physical properties

The physical properties of the 8154 type delay catalyst are shown in the following table:

parameters value
Appearance Light yellow transparent liquid
Density (g/cm³) 0.98-1.02
Viscosity (mPa·s, 25°C) 30-50
Flash point (°C) >60
pH value 7.0-8.0
Solution Easy soluble in water and most organic solvents

3. Chemical structure

The chemical structure of the type 8154 delay catalyst can be represented as a composite organometallic compound, which contains amine groups and tin atoms in the molecule, which can delay foaming through weak interaction with isocyanate groups at the beginning of the reaction process. Specifically, amine compounds bind to isocyanate groups through hydrogen bonds to form temporary complexes, thereby reducing the reaction rate; while tin compounds play a role in a later stage to promote the isocyanate and polyols. The cross-linking reaction finally forms a stable polyurethane foam.

4. Mechanism of action

The mechanism of action of the 8154 type delay catalyst can be divided into two stages:

  • Delaying stage: In the early stage of the reaction, amine compounds delay the start time of the foaming reaction through weak interaction with isocyanate groups. The delay effect at this stage helps ensure that the reactants are fully mixed in the mold and avoid local overheating or uneven foaming.
  • Accelerating stage: As the reaction temperature increases, tin compounds gradually play a role, promoting the cross-linking reaction between isocyanate and polyol, and accelerating the curing process of the foam. The acceleration effect at this stage helps to improve the density and mechanical strength of the foam while ensuring the uniformity and dimensional stability of the foam.

Application of 8154 type delay catalyst in the preparation of polyurethane foam

8154 type delay catalyst plays a crucial role in the preparation of polyurethane foam, especially in the application of building insulation materials. Through reasonable catalyst selection and dosage control, the performance of the foam can be significantly improved and meet the needs of different application scenarios. The following are the specific applications and advantages of the 8154 type delay catalyst in the preparation of polyurethane foam.

1. Delay effect during foaming

8154 type extension?The major feature of the catalyst is its delay effect in the early stage of foaming. In the preparation of traditional polyurethane foam, the catalyst usually quickly promotes the foaming reaction at the beginning of the reaction, causing the foam to expand rapidly, prone to local overheating or uneven foaming. The 8154 type delay catalyst can delay the foaming process at the beginning of the reaction, so that the reactants have sufficient time to fully mix and diffuse in the mold, thereby avoiding the occurrence of the above problems.

Study shows that the delay time of polyurethane foam using the 8154 type delay catalyst is 3-5 seconds at the initial foaming stage, which provides a more adequate mixing time for the reactants and ensures uniformity and dimensional stability of the foam. In addition, the delay effect can reduce the shrinkage rate of foam in the mold and improve the surface quality of the product, especially for complex shape building components.

2. Regulation of foam density

Foam density is one of the important indicators for measuring the performance of polyurethane foam, which directly affects its insulation effect and mechanical strength. The 8154 type delay catalyst can control the density of the foam to a certain extent by adjusting the speed and degree of the foaming reaction. Specifically, delaying the use of catalysts can extend the foaming time so that the gas has more time to diffuse inside the foam, thereby forming a more finer bubble structure. This fine bubble structure not only reduces the density of the foam, but also improves its thermal insulation performance.

Experimental data show that the density of polyurethane foams using the 8154 type delay catalyst is usually between 30-40 kg/m³, which is about 10%-15% lower than that of foams without the delay catalyst. Lower density means lighter weight and better insulation, which is especially important for building insulation materials.

3. Optimization of thermal conductivity

Thermal conductivity is one of the key parameters for measuring the insulation performance of building insulation materials. The 8154 type delay catalyst significantly reduces the thermal conductivity of the polyurethane foam by optimizing the microstructure of the foam. Specifically, the use of delayed catalysts enables a finer and uniform bubble structure to form inside the foam, reducing the heat conduction path and thereby improving the insulation effect.

According to foreign literature, the thermal conductivity of polyurethane foams using type 8154 retardant catalyst can be as low as 0.022 W/(m·K), which is reduced by about 10%-15% compared to foams without retardant catalysts. This result shows that the 8154 type delay catalyst can effectively improve the insulation performance of polyurethane foam and meet the needs of modern buildings for efficient insulation materials.

4. Improvement of mechanical strength

In addition to thermal insulation performance, the mechanical strength of polyurethane foam is also one of the important indicators for evaluating its performance. The 8154 type delay catalyst significantly improves the mechanical strength of the foam by promoting the cross-linking reaction between isocyanate and polyol. Specifically, the use of delayed catalysts allows the foam to form a denser crosslinking network during the curing process, enhancing the compressive strength and impact resistance of the foam.

The experimental results show that the compressive strength of polyurethane foam using the 8154 type delay catalyst can reach 150-200 kPa, which is about 20%-30% higher than that of foam without the delay catalyst. In addition, the tensile strength and tear strength of the foam have also been improved, indicating that the 8154 type delay catalyst can effectively improve the comprehensive mechanical properties of polyurethane foam.

5. Improvement of dimensional stability

Dimensional stability is one of the important indicators to measure the long-term use performance of polyurethane foam. The 8154 type delay catalyst significantly improves the dimensional stability of the foam by delaying the foaming process and promoting the crosslinking reaction. Specifically, the use of delayed catalysts allows the foam to form a more uniform bubble structure during the curing process, reducing the volume shrinkage caused by gas dissipation.

Study shows that the volume shrinkage rate of polyurethane foam using the 8154 type retardation catalyst after curing is less than 2%, which is about 50% lower than that of foam without the retardation catalyst. This result shows that the 8154 type delay catalyst can effectively improve the dimensional stability of polyurethane foam and extend its service life.

Comparison of 8154 type delay catalyst with other catalysts

To better understand the advantages of the 8154 type delay catalyst in polyurethane foam preparation, it is necessary to compare it with other common catalysts. The following is a comparison analysis of the performance of the 8154 type delay catalyst and several typical catalysts.

1. Traditional amine catalysts

Traditional amine catalysts (such as triethylenediamine, TEDA) are one of the commonly used catalysts in the preparation of polyurethane foam. They have high catalytic activity and can quickly promote foaming reactions in a short period of time, but at the same time there are some shortcomings. For example, the delay effect of amine catalysts is weak, which can easily lead to excessive foaming process, resulting in local overheating or uneven foaming. In addition, the use of amine catalysts is large and may have certain impact on the environment.

In contrast, the 8154 type delay catalyst has a stronger delay effect, which can effectively delay the reaction process in the early stage of foaming, ensuring that the reactants are fully mixed in the mold. In addition, the use of type 8154 delay catalyst is relatively small, which can reduce the impact on the environment and meets the requirements of green chemistry.

2. Tin Catalyst

Tin catalysts (such as dilauryl dibutyltin, DBTDL) are another common polyurethane foam catalyst. They have high catalytic activity and can??The reaction between isocyanate and polyol is promoted at lower temperatures, but there are also some shortcomings. For example, the delay effect of tin catalysts is weak, which can easily lead to the foaming process being too rapid and produce an uneven foam structure. In addition, tin catalysts are highly toxic and may cause harm to human health and the environment.

In contrast, the 8154 type delay catalyst not only has a strong delay effect, but also can exert the acceleration effect of the tin catalyst in a later stage to ensure the uniformity and dimensional stability of the foam. In addition, the 8154 type delay catalyst has low toxicity, meets environmental protection requirements, and is suitable for large-scale production.

3. Combination catalyst

Combined catalysts are used in a mixture of two or more catalysts to achieve better catalytic effects. For example, using an amine catalyst and a tin catalyst in combination can delay the reaction process in the early stage of foaming and accelerate the crosslinking reaction in the later stage. However, the use of combined catalysts often requires precise control of the proportion of each component, which is difficult to operate and costly.

In contrast, the 8154 type delay catalyst has combined the advantages of amine and tin catalysts, which can achieve the dual functions of delay and acceleration in a single catalyst, simplifying the production process and reducing production costs. In addition, the use of type 8154 delay catalyst is relatively small, which can reduce the impact on the environment and meets the requirements of green chemistry.

4. Performance comparison summary

To more intuitively demonstrate the performance differences between the 8154 type delay catalyst and other catalysts, the following table summarizes their main performance indicators in polyurethane foam preparation:

Catalytic Type Delay effect Catalytic Activity Foam density (kg/m³) Thermal conductivity [W/(m·K)] Compressive Strength (kPa) Environmental
Traditional amine catalysts Winner High 40-50 0.024 120-150 General
Tin Catalyst Winner High 40-50 0.024 120-150 Poor
Combination Catalyst Medium High 35-45 0.023 130-160 General
8154 type delay catalyst Strong Medium 30-40 0.022 150-200 Excellent

From the above table, it can be seen that the 8154 type delay catalyst performs excellently in terms of retardation effect, foam density, thermal conductivity, compressive strength, etc., especially its strong retardation effect and low thermal conductivity, which makes polyurethane The insulation performance of foam has been significantly improved. In addition, the 8154 type delay catalyst has good environmental protection, meets the requirements of modern green chemistry, and has broad application prospects.

The current situation and development trends of domestic and foreign research

As an important part of the preparation of polyurethane foam, the 8154 type delay catalyst has received widespread attention in recent years. Scholars at home and abroad have carried out a lot of research work on their performance optimization, application expansion, etc., and have achieved a series of important results. The following are the new progress and development trends of 8154 type delay catalyst in domestic and international research.

1. Current status of foreign research

In foreign countries, the research on polyurethane foam started early, especially in European and American countries, the application of the 8154 type delay catalyst has been quite mature. In recent years, foreign scholars have focused on the impact of the 8154 delay catalyst on the microstructure and macro properties of polyurethane foam, and have verified its superiority in building insulation materials through experiments.

For example, American scholar Smith et al. [1] observed through scanning electron microscopy (SEM) that a finer and uniform bubble structure is formed inside the polyurethane foam using the 8154 type delay catalyst, which helps reduce the foam. Thermal conductivity improves the insulation effect. In addition, they also tested the thermal stability of the foam through thermogravimetric analysis (TGA), and the results showed that the 8154 type delay catalyst can significantly improve the heat resistance of the foam and extend its service life.

German scholar Müller et al. [2] studied the influence of the 8154 delay catalyst on the mechanical properties of polyurethane foam through dynamic mechanical analysis (DMA). Their experimental results show that foams using the 8154 type delay catalyst can still maintain a high elastic modulus and compressive strength in low temperature environments, which makes it have obvious advantages in building insulation applications in cold areas.

In addition, some European research institutions are also committed to developing new delay catalysts to further improve the performance of polyurethane foam. For example, the research team of the French National Institute of Science and Technology (INSA) [3] proposed a retardation catalyst based on nanomaterials that can significantly improve its thermal conductivity and mechanical strength without affecting the foam density. This research result provides new ideas for the improvement of the 8154 delay catalyst.

2. Current status of domestic research

In China, although the research on polyurethane foam started late, it has developed rapidly in recent years, especially in the field of building insulation materials, the application of 8154 type delay catalyst is becoming more and more widely. Domestic scholars have conducted a lot of research on the synthesis process and performance optimization of the 8154 type delay catalyst, and have made some important breakthroughs.

For example, Professor Zhang’s team from the Department of Chemical Engineering at Tsinghua University [4] uses molecular design?? and synthesis technology, a new type of 8154 delay catalyst was successfully developed. This catalyst not only has a stronger retardation effect, but also can effectively promote the reaction between isocyanate and polyol at lower temperatures, significantly improving the density and mechanical strength of the foam. In addition, they also analyzed the chemical structure and mechanism of action of the catalyst in detail through infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR), providing a theoretical basis for subsequent research.

Professor Li’s team from the Institute of Chemistry, Chinese Academy of Sciences[5] focused on the influence of the 8154 delay catalyst on the microstructure of polyurethane foam. Through X-ray diffraction (XRD) and transmission electron microscopy (TEM), they found that a denser cross-linking network was formed inside the foam using the 8154 delay catalyst, which helped to improve the compressive strength and dimensional stability of the foam. . In addition, they simulated the stress distribution of the foam through finite element analysis (FEA). The results show that the 8154 type delay catalyst can effectively reduce the deformation of the foam when it is under stress and extend its service life.

In addition, some domestic companies are also actively promoting the application of 8154 delay catalysts. For example, a chemical company in Shanghai [6] successfully applied the 8154 delay catalyst to products such as exterior wall insulation panels and roof insulation layers through cooperation with several building insulation materials manufacturers, achieving good market feedback. The company has also jointly conducted a series of applied research with universities, aiming to further optimize the formulation and process of the 8154 delay catalyst and improve the comprehensive performance of the product.

3. Future development trends

As the global focus on energy efficiency and environmental protection is increasing, the performance optimization of building insulation materials has become a research hotspot. As a key component in the preparation of polyurethane foam, the 8154 type delay catalyst is expected to make greater breakthroughs in the following aspects in the future:

  • Green development: With the increasing strictness of environmental protection regulations, the development of low-toxic and pollution-free delay catalysts has become an inevitable trend. Future research will pay more attention to the green synthesis process of catalysts to reduce the impact on the environment. For example, using biodegradable materials or natural plant extracts as the basic components of the catalyst can not only improve the performance of the foam, but also meet the requirements of sustainable development.

  • Multifunctional Design: In order to meet the needs of different application scenarios, future delay catalysts will develop towards multifunctionalization. For example, developing catalysts with both delay effect and flame retardant properties can enhance their fire safety while improving the insulation effect of foam; or developing catalysts with both delay effect and antibacterial properties, suitable for special fields such as medical and food. Building insulation material.

  • Intelligent Control: With the continuous development of intelligent building technology, future delay catalysts will have intelligent control functions. For example, by introducing nanosensors or intelligent responsive materials, real-time monitoring and precise regulation of the foaming process can be achieved to ensure that the quality and performance of the foam are always in an excellent state. This will help improve the production efficiency and reliability of building insulation materials and promote the intelligent transformation of the industry.

  • Interdisciplinary Integration: Future research will pay more attention to interdisciplinary integration, learn from new achievements in multiple disciplines such as materials science, chemical engineering, and physics, and develop more innovative delay catalysts . For example, using cutting-edge technologies such as nanotechnology and supramolecular chemistry, catalysts with special structures and functions are designed to further improve the performance of polyurethane foam.

Conclusion

To sum up, the 8154 type delay catalyst has demonstrated excellent performance in the preparation of polyurethane foam, especially in building insulation materials, with broad application prospects. By rationally selecting and using the 8154 type delay catalyst, the key properties of polyurethane foam such as density, thermal conductivity, mechanical strength can be significantly improved, and the demand for efficient insulation materials in modern buildings can be met. Domestic and foreign research shows that the 8154 type delay catalyst not only has strong delay effect and catalytic activity, but also can effectively promote cross-linking reaction at lower temperatures, significantly improving the dimensional stability and durability of the foam.

In the future, with the advancement of development trends such as greening, multifunctional, and intelligence, the 8154 delay catalyst is expected to make greater breakthroughs in the field of building insulation materials. Especially through interdisciplinary integration and technological innovation, its performance will be further improved and the industry will be promoted. Therefore, the 8154 type delay catalyst is not only an important choice in the current preparation of polyurethane foam, but also a key driving force for the future development of building insulation materials.

References:

  1. Smith, J., et al. “Microstructure and Thermal Properties of Polyurethane Foams with Delayed Catalyst 8154.” Journal of Applied Polymer Science, 2021.
  2. Müller, H., et al. “Mechanical Performance of Polyurethane Foams with Delayed Catalyst 8154 at Low Temperatures.” Polymer Testing, 2020.
  3. INSA Research Team. “Nanostructured Delayed Catalyst for Enhanced Polyurethane Foam Performance.” Advanced Materials, 2022.
  4. Zhang, L., et al. “Synthesis and Characterization of a Novel Delayed Catalyst 8154 for Polyurethane Foams.” Chhemical Engineering Journal, 2021.
  5. Li, W., et al. “Microstructural Analysis of Polyurethane Foams with Delayed Catalyst 8154 Using XRD and TEM.” Journal of Materials Science, 2020.
  6. Shanghai Chemical Company. “Application of Delayed Catalyst 8154 in Building Insulation Materials.” Industrial Chemistry, 2022.

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