Low-Fogging, Odorless Catalyst (LFOC) has important application value in the field of composite materials. With the continuous improvement of global awareness of environmental protection and health, the volatile organic compounds (VOCs) and odor problems generated by traditional catalysts during use have gradually become bottlenecks in the development of the industry. The emergence of LFOC not only solves these problems, but also improves the performance of composite materials, making it widely used in many fields. This article will discuss the performance of LFOC in composite materials in detail, including its product parameters, application scenarios, advantages and challenges, and conduct in-depth analysis in combination with new research literature at home and abroad.

Composite materials are materials systems composed of two or more materials of different properties, usually composed of matrix materials and reinforcement materials. Common composite materials include glass fiber reinforced plastic (GFRP), carbon fiber reinforced plastic (CFRP), polyurethane foam, etc. These materials have been widely used in aerospace, automobile manufacturing, construction, sporting goods and other fields due to their excellent mechanical properties, lightweight and corrosion resistance. However, traditional catalysts often produce large amounts of VOCs and odors during the preparation of composite materials, which not only affects the production environment, but may also cause harm to human health. Therefore, the development of low atomization and odorless catalysts has become an important topic in the composite materials industry.

In recent years, significant progress has been made in the research of LFOC, especially in thermoset composite materials such as polyurethane and epoxy resin. LFOC reduces the generation of by-products by optimizing the catalytic reaction path, thereby reducing the emission of VOCs and the generation of odors. In addition, LFOC can also improve the curing speed of composite materials, improve surface quality, enhance mechanical properties, etc. This article will conduct a systematic analysis of the performance of LFOC in composite materials from multiple perspectives, aiming to provide valuable reference for researchers and enterprises in related fields.

The basic principles of low atomization and odorless catalyst

The core of the low atomization odorless catalyst (LFOC) is its unique chemical structure and catalytic mechanism, which can significantly reduce the generation of volatile organic compounds (VOCs) and the emanation of odor without sacrificing catalytic efficiency. The main components of LFOC are usually organometallic compounds, amine compounds or derivatives thereof that promote the curing process of composite materials through specific chemical reaction paths while inhibiting the generation of by-products. Here is how LFOC works and how it differs from other types of catalysts.

1. Chemical structure and catalytic mechanism of LFOC

The chemical structure design of LFOC is designed to optimize its catalytic activity and selectivity. Common LFOCs include organotin compounds, organobis compounds, organozinc compounds, etc. These compounds have high thermal and chemical stability and are able to effectively catalyze the crosslinking reaction of composites at lower temperatures without decomposing into harmful by-products. For example, organotin catalysts (such as dilauryl dibutyltin, DBTDL) are commonly used in polyurethane systems, but they are easily decomposed at high temperatures, resulting in volatile tin compounds and odors. In contrast, LFOC increases the thermal stability of the catalyst by introducing large sterically hindered groups or ligands and reduces the generation of by-products.

The catalytic mechanism of LFOC mainly depends on its electron transfer and coordination with the reactants. Taking the polyurethane system as an example, LFOC can accelerate the reaction between isocyanate (-NCO) and polyol (-OH) and form aminomethyl ester bonds (-NH-CO-O-), thereby achieving curing of composite materials. At the same time, LFOC can also inhibit the occurrence of side reactions, such as the autopolymerization of isocyanate or reaction with water, thereby reducing the generation of carbon dioxide (CO2) and other volatile by-products. This selective catalytic mechanism allows LFOC to significantly reduce VOCs emissions and odor generation while maintaining efficient catalytic performance.

2. Comparison of LFOC and other catalysts

To better understand the advantages of LFOC, we can compare it with conventional catalysts. Table 1 lists the performance characteristics of several common catalysts, including traditional organotin catalysts, amine catalysts, and LFOCs.

It can be seen from Table 1 that although traditional organotin catalysts have high catalytic efficiency, their VOCs emission and odor problems are relatively serious, and their thermal stability is poor, and they are prone to decomposition at high temperatures. Amines catalysts perform in terms of catalytic efficiency and thermal stability, and their strong amine smell seriously affects the production environment and product quality. In contrast, LFOC not only has efficient catalytic performance, but also can significantly reduce the emission of VOCs and the generation of odors, showing thatThermal stability and wide applicability.

3. Application scenarios of LFOC

LFOC is widely used in the preparation process of various composite materials, especially in occasions where environmental and health requirements are high. For example, in the production of automotive interior materials, LFOC can effectively reduce the concentration of VOCs in the vehicle and improve the air quality in the vehicle; in the preparation of building insulation materials, LFOC can reduce odor during construction and improve the working environment of workers; In the aerospace field, LFOC helps to improve the mechanical properties and weather resistance of composite materials, meeting stringent use requirements. In addition, LFOC is also suitable for food packaging and medical devices that require extremely high hygiene standards, ensuring the safety and reliability of products.

Product parameters of low atomization odorless catalyst

In order to better understand the application effect of LFOC in composite materials, we need to conduct a detailed analysis of its specific product parameters. The performance parameters of LFOC mainly include catalytic activity, thermal stability, VOCs emissions, odor intensity, storage stability, etc. The following are the specific parameters of several common LFOCs and their impact on the properties of composite materials.

1. Catalytic activity

Catalytic activity is one of the key indicators for measuring LFOC performance. High catalytic activity means that the catalyst can promote the curing reaction of composite materials in a shorter time, shorten the production cycle and improve production efficiency. The catalytic activity of LFOC is usually evaluated by determining its reaction rate constant under specific reaction conditions. Table 2 lists the catalytic activity data for several common LFOCs.

It can be seen from Table 2 that there are differences in catalytic activity of different types of LFOCs. The catalytic activity of organic titanium catalyst is high and can complete the curing reaction in a short time. It is suitable for occasions with high production efficiency requirements. The catalytic activity of organic bismuth catalyst is relatively low, but its thermal stability and low VOCs emission characteristics make It has more advantages in some special applications. Choosing the appropriate LFOC type requires comprehensive consideration of the type, production process and performance requirements of the composite material.

2. Thermal Stability

Thermal stability is the ability of LFOC to maintain catalytic properties under high temperature environments. Good thermal stability can prevent the catalyst from decomposing at high temperatures, reduce the generation of by-products, and extend the service life of the catalyst. The thermal stability of LFOC is usually tested by thermogravimetric analysis (TGA) or differential scanning calorimetry (DSC). Table 3 lists the thermal stability data for several common LFOCs.

It can be seen from Table 3 that organic titanium catalysts have high thermal stability and can maintain good catalytic performance within a wide temperature range, which is suitable for high-temperature curing processes; the thermal stability of organic bismuth catalysts is slightly inferior to that of , but it performs excellently in low-temperature curing processes; organic zinc catalysts are between the two, suitable for medium-temperature curing processes. Choosing LFOC with appropriate thermal stability ensures the curing quality of the composite material under different temperature conditions.

3. VOCs emissions

VOCs emissions are an important indicator for measuring the environmental performance of LFOC. Low VOCs emissions can not only reduce environmental pollution, but also improve the production environment and protect workers’ health. The VOCs emissions of LFOCs are usually detected by gas chromatography-mass spectrometry (GC-MS) or Fourier transform infrared spectroscopy (FTIR). Table 4 lists the VOCs emission data for several common LFOCs.

It can be seen from Table 4 that all types of LFOCs exhibit extremely low VOCs emissions, especially organic titanium catalysts, whose VOCs emissions are low and meet the A+ environmental standards. This makes LFOC have obvious advantages in industries with strict environmental protection requirements, such as automotive interiors, building insulation, food packaging, etc.

4. Odor intensity

Odor intensity is an important factor in measuring the impact of LFOC on the production environment and product quality. Odorless or low-odor LFOC can significantly improve the production environment and avoid the impact of odor on workers’ health and product quality. The odor intensity of LFOC is usually evaluated by sensory evaluation or gas chromatography-olfactory measurement (GC-O). Table 5 lists severalOdor intensity data of common LFOC.

As can be seen from Table 5, all types of LFOCs exhibit extremely low odor intensity, especially organic bismuth catalysts and organic titanium catalysts, which are almost odorless and suitable for odor-sensitive occasions such as automotive interiors, food Packaging and aerospace.

5. Storage Stability

Storage stability refers to the ability of LFOC to maintain its physical and chemical properties during long-term storage. Good storage stability can extend the shelf life of the catalyst, reduce waste and reduce production costs. The storage stability of LFOC is usually evaluated by accelerated aging tests or long-term storage tests. Table 6 lists the storage stability data for several common LFOCs.

It can be seen from Table 6 that organic titanium catalysts have a long shelf life and can be stored at room temperature for 4 years, which is suitable for long-term storage and transportation; the shelf life of organic bismuth catalysts and organic zinc catalysts is 2 years and 3 years respectively. It also has good storage stability. Choosing an LFOC with proper storage stability ensures that it maintains good catalytic performance after long storage.

Application of low atomization and odorless catalysts in composite materials

Low atomization odorless catalyst (LFOC) is widely used in composite materials, especially in thermosetting composite materials such as polyurethane, epoxy resin, and vinyl esters. LFOC can not only improve the curing speed of composite materials, improve surface quality and enhance mechanical properties, but also significantly reduce the emission of VOCs and the generation of odors, meeting the strict requirements of modern industry for environmental protection and health. The following will introduce the application and performance of LFOC in different types of composite materials in detail.

1. Polyurethane composite material

Polyurethane (PU) is a widely used thermoset composite material with excellent mechanical properties, wear resistance and chemical corrosion resistance. Traditional polyurethane catalysts such as organotin compounds and amine compounds will produce a large number of VOCs and odors during the curing process, affecting the production environment and product quality. The introduction of LFOC effectively solved these problems and significantly improved the performance of polyurethane composite materials.

1.1 Curing speed

LFOC can accelerate the cross-linking reaction of polyurethane, shorten the curing time and improve production efficiency. Studies have shown that the curing time of polyurethane composites using LFOC can be shortened to 10-15 minutes, which is significantly reduced compared to the curing time of traditional catalysts (20-30 minutes). This not only increases the speed of the production line, but also reduces energy consumption and equipment occupancy time and reduces production costs.

1.2 Surface quality

The efficient catalytic properties of LFOC make the surface of polyurethane composites smoother and more uniform, reducing the generation of bubbles and cracks. The experimental results show that the surface roughness of polyurethane products using LFOC was reduced by about 30% and the gloss was improved by 20%. This not only improves the appearance quality of the product, but also enhances its scratch resistance and weather resistance.

1.3 Mechanical Properties

LFOC can promote the cross-linking density of polyurethane molecular chains, thereby improving the mechanical properties of composite materials. Studies have shown that the tensile strength, compression strength and impact strength of polyurethane composites using LFOC have been improved by 15%, 20% and 25%, respectively. In addition, LFOC can improve the flexibility of polyurethane, making it less likely to crack in low temperature environments, and is suitable for applications in cold areas.

1.4 Environmental performance

The introduction of LFOC significantly reduces the emission of VOCs and the generation of odors of polyurethane composites during curing. Experimental data show that the VOCs emissions of polyurethane products using LFOC are reduced by more than 90% compared with traditional catalysts, and there is almost no odor. This not only improves the production environment, but also complies with the requirements of the EU REACH regulations and the Chinese GB/T 18587-2017 standards, and is suitable for occasions with strict environmental protection requirements, such as automotive interiors, building insulation and food packaging.

2. Epoxy resin composite material

Epoxy resin (EP) is a high-performance composite material widely used in aerospace, electronics and electrical appliances, building materials and other fields. Traditional epoxy resin catalysts such as amine compounds will produce a strong amine odor during the curing process, affecting the production environment and product quality. The introduction of LFOC effectively solved this problem and significantly improved the performance of epoxy resin composites.

2.1 Curing speed

LFOC can accelerate the cross-linking reaction of epoxy resin, shorten the curing time and improve production efficiency. Research shows that the curing time of epoxy resin composites using LFOC can be reduced� to 8-12 hours, the curing time (12-24 hours) is greatly reduced compared to the traditional catalyst. This not only increases the speed of the production line, but also reduces energy consumption and equipment occupancy time and reduces production costs.

2.2 Surface quality

The efficient catalytic properties of LFOC make the surface of epoxy resin composites smoother and evenly, reducing the generation of bubbles and cracks. The experimental results show that the surface roughness of epoxy resin products using LFOC was reduced by about 25% and the gloss was improved by 15%. This not only improves the appearance quality of the product, but also enhances its scratch resistance and weather resistance.

2.3 Mechanical properties

LFOC can promote the cross-linking density of the molecular chain of epoxy resin, thereby improving the mechanical properties of composite materials. Research shows that the tensile strength, compression strength and impact strength of epoxy resin composites using LFOC have been improved by 10%, 15% and 20%, respectively. In addition, LFOC can improve the heat resistance and chemical corrosion resistance of epoxy resin, making it better stable in high temperature and harsh environments.

2.4 Environmental performance

The introduction of LFOC significantly reduces the emission of VOCs and the generation of odors of epoxy resin composites during curing. Experimental data show that the VOCs emissions of epoxy resin products using LFOC are reduced by more than 85% compared with traditional catalysts, and there is almost no odor. This not only improves the production environment, but also complies with the requirements of the EU REACH regulations and the Chinese GB/T 18587-2017 standard, and is suitable for occasions with strict environmental protection requirements, such as aerospace, electronics and medical devices.

3. Vinyl ester composite material

Vinyl ester (VE) is a high-performance composite material widely used in corrosion-resistant, chemical-resistant and high-temperature environments. Traditional vinyl ester catalysts such as peroxides will produce a large number of VOCs and odors during the curing process, affecting the production environment and product quality. The introduction of LFOC effectively solved these problems and significantly improved the performance of vinyl ester composites.

3.1 Curing speed

LFOC can accelerate the cross-linking reaction of vinyl ester, shorten the curing time and improve production efficiency. Studies have shown that the curing time of vinyl ester composites using LFOC can be shortened to 6-10 hours, which is significantly reduced compared to the curing time of traditional catalysts (12-24 hours). This not only increases the speed of the production line, but also reduces energy consumption and equipment occupancy time and reduces production costs.

3.2 Surface quality

The efficient catalytic properties of LFOC make the surface of vinyl ester composites smoother and more uniform, reducing the generation of bubbles and cracks. The experimental results show that the surface roughness of vinyl ester products using LFOC was reduced by about 20% and the gloss was improved by 10%. This not only improves the appearance quality of the product, but also enhances its scratch resistance and weather resistance.

3.3 Mechanical Properties

LFOC can promote the cross-linking density of vinyl ester molecular chains, thereby improving the mechanical properties of composite materials. Studies have shown that the tensile strength, compression strength and impact strength of vinyl ester composites using LFOC have been improved by 12%, 18%, and 22%, respectively. In addition, LFOC can improve the heat resistance and chemical corrosion resistance of vinyl ester, making it better stable in high temperature and harsh environments.

3.4 Environmental performance

The introduction of LFOC significantly reduces the emission of VOCs and the generation of odors of vinyl ester composites during curing. Experimental data show that the VOCs emissions of vinyl ester products using LFOC are reduced by more than 80% compared with traditional catalysts, and there is almost no odor. This not only improves the production environment, but also complies with the requirements of the EU REACH regulations and the Chinese GB/T 18587-2017 standards, and is suitable for occasions with strict environmental protection requirements, such as chemical equipment, marine engineering and petroleum pipelines.

Advantages and challenges of low atomization odorless catalyst

The use of low atomization odorless catalyst (LFOC) in composite materials has brought many advantages, but it also faces some challenges. The following is a detailed analysis of its strengths and challenges.

1. Advantages

1.1 Excellent environmental performance

The big advantage of LFOC is that it significantly reduces the emission of VOCs and the generation of odors of composite materials during curing. Traditional catalysts such as organotin compounds and amine compounds will release a large amount of harmful gases during the curing process, such as formaldehyde, dimethyl, etc. These substances not only cause pollution to the environment, but also cause harm to human health. LFOC reduces the generation of by-products by optimizing the catalytic reaction path, making the production process of composite materials more environmentally friendly. Studies have shown that the emission of VOCs of composite materials using LFOC is 80%-90% lower than that of traditional catalysts, and there is almost no odor. This not only complies with the increasingly strict environmental regulations around the world, such as the EU REACH regulations and the Chinese GB/T 18587-2017 standards, but also enhances the sense of social responsibility of enterprises and enhances market competitiveness.

1.2 Improve Production Efficiency

LFOC has efficient catalytic properties, which can significantly shorten the curing time of composite materials and improve production efficiency. Traditional catalysts often take a long time to complete the crosslinking reaction during the curing process, resulting in an extended production cycle and an increase in equipment occupancy time. LFOC accelerates crosslinking reactions, shortens curing time, reduces energy consumption and equipment occupancy time, and reduces production costs. For example, in the production of polyurethane composites, the curing time using LFOC can be shortened to 10-15 minutes, which is a significant reduction compared to the 20-30 minutes of conventional catalysts. This not only increases the speed of the production line, but also reduces the scrap rate and improves production.��Quality.

1.3 Improve product performance

The introduction of LFOC not only improves the curing speed of the composite material, but also significantly improves its mechanical properties and surface quality. Research shows that the tensile strength, compression strength and impact strength of composite materials using LFOC have been increased by 10%-25%, the surface roughness has been reduced by 20%-30%, and the gloss has been improved by 10%-20%. In addition, LFOC can improve the flexibility and weather resistance of composite materials, making them less likely to crack in low temperature environments, and are suitable for applications in cold areas. These performance improvements give LFOC a clear competitive advantage in high-end products and special applications, such as aerospace, automotive interiors, building insulation and food packaging.

1.4 Wide applicability

LFOC is suitable for a variety of composite materials, including thermosetting composite materials such as polyurethane, epoxy resin, vinyl esters, etc. Different LFOC types can be selected according to the type of composite materials and production processes to meet different performance requirements. For example, organic bismuth catalysts are suitable for low-temperature curing processes, organic zinc catalysts are suitable for medium-temperature curing processes, and organic titanium catalysts are suitable for high-temperature curing processes. The wide applicability of LFOC has made it widely used in many industries, such as automobile manufacturing, construction, electronics and electrical appliances, medical devices, etc.

2. Challenge

2.1 Higher cost

Although LFOC has significant advantages in environmental performance and product performance, its production costs are relatively high. The synthesis process of LFOC is complex and the raw materials are expensive, resulting in its market price higher than that of traditional catalysts. For some cost-sensitive businesses, the high cost of LFOC may become a barrier to promotion. Therefore, how to reduce the production cost of LFOC and improve its cost-effectiveness is one of the key directions of future research.

2.2 High technical threshold

The synthesis and application technology of LFOC is highly required and requires professional technicians to operate and maintain. The catalytic mechanism of LFOC is complex and involves the selection and regulation of multiple chemical reaction paths. Enterprises need to have certain technical R&D capabilities to fully utilize their advantages. In addition, the use conditions of LFOC are relatively strict, such as temperature, humidity, reaction time and other parameters, which require precise control, otherwise it may affect its catalytic effect. Therefore, enterprises need to provide sufficient technical training and technical support when introducing LFOC to ensure its smooth application.

2.3 Low market awareness

Although LFOC has significant advantages in environmental protection and performance, its awareness of it is still low in the market. Many companies lack sufficient understanding of the advantages and application prospects of LFOC and still tend to use traditional catalysts. In addition, the promotion of LFOC also needs to overcome some industry inertia and market resistance, such as the supply chain maturity of traditional catalysts and customer habits. Therefore, strengthening market publicity and technology promotion and improving LFOC market awareness are the key to promoting its widespread application.

Conclusion and Outlook

The application of low atomization odorless catalyst (LFOC) in composite materials has brought significant environmental protection and performance advantages, solving the bottleneck problems of traditional catalysts in VOCs emissions and odors. LFOC can not only improve the curing speed of composite materials, improve surface quality and enhance mechanical properties, but also significantly reduce the emission of VOCs and the generation of odors, which is in line with the increasingly stringent environmental regulations around the world. However, the high cost, technical barriers and low market awareness of LFOC still restrict its widespread application. In the future, with the improvement of synthesis processes and the reduction of production costs, LFOC is expected to be promoted in more fields and become the mainstream catalyst in the composite materials industry.

Looking forward, the development direction of LFOC is mainly concentrated in the following aspects:

1. Reduce costs: By optimizing the synthesis process and finding more economical raw materials, reduce the production cost of LFOC, improve its cost-effectiveness, and enable it to be applied in more small and medium-sized enterprises.

2. Technical Innovation: Further study the catalytic mechanism of LFOC, develop new catalysts, and expand their application scope, especially in extreme conditions such as high temperature and high pressure.

3. Market Promotion: Strengthen market publicity and technical support, improve LFOC’s market awareness, and promote its widespread application in automobile manufacturing, construction, electronics and electrical industries.

4. Policy Support: The government should introduce relevant policies to encourage enterprises to adopt environmentally friendly catalysts, increase support for the research and development and application of LFOCs, and promote the green transformation of the composite materials industry.

In short, as a new generation of environmentally friendly catalyst, LFOC has broad application prospects and development potential. With the continuous advancement of technology and the gradual maturity of the market, LFOC will surely play an increasingly important role in the composite materials industry and promote the sustainable development of the industry.