Application of bismuth isooctanoate in rubber vulcanization and its impact on the environment

Abstract

Rubber vulcanization is a key process to improve the performance of rubber materials. Through cross-linking reaction, rubber molecules form a three-dimensional network structure, thereby improving its mechanical properties, heat resistance and chemical resistance. Bismuth Neodecanoate, as an efficient organometallic catalyst, shows unique advantages in the rubber vulcanization process. This article reviews the application of bismuth isooctanoate in rubber vulcanization, analyzes its catalytic mechanism and its impact on rubber properties, and discusses its impact on the environment. Research results show that bismuth isooctanoate has a significant catalytic effect in rubber vulcanization, which can improve vulcanization efficiency and rubber properties while having lower environmental risks.

1. Introduction

Rubber materials are widely used in industry and daily life because of their excellent elasticity and durability. However, unvulcanized natural rubber or synthetic rubber has problems such as poor mechanical properties and low heat resistance. Vulcanization is a process in which rubber molecules form a three-dimensional network structure through chemical cross-linking reactions, which can significantly improve the mechanical properties, heat resistance and chemical resistance of rubber. Traditional sulfurization catalysts mainly include sulfur, peroxides, metal oxides, etc. However, these catalysts often have problems such as slow reaction rates, high toxicity, and serious environmental pollution. In recent years, bismuth isooctanoate, as an efficient organometallic catalyst, has shown unique advantages in rubber vulcanization and has attracted widespread attention.

2. Properties of bismuth isooctanoate

Bismuth isooctanoate is a colorless to light yellow transparent liquid with the following main characteristics:

Thermal stability: Stable at high temperatures and not easy to decompose.
Chemical Stability: Demonstrates good stability in a variety of chemical environments.
Low toxicity and low volatility: Compared with other organometallic catalysts, bismuth isooctanoate is less toxic and less volatile, making it safer to use.
High catalytic activity: It can effectively promote a variety of chemical reactions, especially showing excellent catalytic performance in esterification, alcoholysis, epoxidation and other reactions.

3. Catalytic mechanism of bismuth isooctanoate in rubber vulcanization

3.1 Basic principles of vulcanization reaction

Rubber vulcanization is a process in which cross-linking agents (such as sulfur, peroxide, etc.) react with double bonds in rubber molecules to form a three-dimensional network structure. Cross-linking reactions can significantly improve the mechanical properties, heat resistance and chemical resistance of rubber.

3.2 Catalytic mechanism of bismuth isooctanoate

The catalytic mechanism of bismuth isooctanoate in the rubber vulcanization process mainly includes the following steps:

Proton transfer: The bismuth ion in bismuth isooctanoate can accept the proton of the double bond in the rubber molecule to form an intermediate.
Nucleophilic attack: The bismuth ions in the intermediate undergo nucleophilic attack with the cross-linking agent (such as sulfur, peroxide, etc.) to form a new intermediate.
Proton transfer: The proton in the new intermediate is transferred to another rubber molecule to form a cross-linked structure.
Catalyst regeneration: The generated cross-linked structure recombines with bismuth ions, the catalyst is regenerated, and continues to participate in the next reaction cycle.

4. Effect of bismuth isooctanoate on rubber properties

4.1 Vulcanization speed

Bismuth isooctanoate can significantly accelerate the vulcanization reaction of rubber and shorten the vulcanization time. This not only improves production efficiency, but also reduces energy consumption and production costs. For example, during the vulcanization process of natural rubber, adding 0.5% bismuth isooctanoate can shorten the vulcanization time from 2 hours to 1 hour.

4.2 Mechanical properties

Bismuth isooctanoate can improve the mechanical properties of rubber and increase the tensile strength, tear strength and wear resistance of vulcanized products. By adjusting the amount of catalyst, the hardness and flexibility of the rubber can be precisely controlled to meet the needs of different application scenarios. For example, during the vulcanization process of synthetic rubber, adding 0.3% bismuth isooctanoate can significantly improve its tensile strength and tear strength.

4.3 Heat resistance

Bismuth isooctanoate can improve the heat resistance of rubber, allowing it to maintain good performance in high temperature environments. This helps extend the service life of rubber products and improves product reliability. For example, during the vulcanization process of high-temperature rubber, adding 0.2% bismuth isooctanoate can significantly improve its thermal stability at high temperatures.

4.4 Chemical resistance

Bismuth isooctanoate can improve the chemical resistance of rubber, making it more stable and corrosion-resistant when exposed to chemicals such as acids, alkalis, and solvents. This helps extend the service life of rubber products and improves product reliability. For example, during the vulcanization process of chemical-resistant rubber, adding 0.1% bismuth isooctanoate can significantly improve its resistance to solvents and chemicals.

5. Application examples of bismuth isooctanoate in rubber vulcanization

5.1 Natural rubber

In order to improve the vulcanization speed and mechanical properties of natural rubber, a tire manufacturer uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the vulcanization time was successfully shortened from 2 hours to 1 hour, while the tensile strength and wear resistance of the tire were improved. Ultimately, the company produces tires with higher mechanical properties andHigh thermal performance, meeting market demand.

5.2 Synthetic rubber

In order to improve the vulcanization speed and mechanical properties of synthetic rubber, a seal manufacturer uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the vulcanization time was successfully shortened from 1.5 hours to 0.5 hours, while the tensile strength and tear strength of the seal were increased. Ultimately, the company produces seals with improved mechanical properties and chemical resistance that meet market demands.

5.3 High temperature rubber

In order to improve the vulcanization speed and heat resistance of high-temperature rubber, an aerospace company uses bismuth isooctanoate as a catalyst. By optimizing the amount of catalyst, the vulcanization time was successfully shortened from 2.5 hours to 1 hour, while the thermal stability of high-temperature rubber at high temperatures was improved. Ultimately, the high-temperature rubber produced by the company has higher heat and chemical resistance and meets the high standards required by the aerospace industry.

6. Impact of bismuth isooctanoate on the environment

6.1 Low toxicity

Bismuth isooctanoate has low toxicity and has less impact on the environment and human health than traditional heavy metal catalysts (such as lead, cadmium, etc.). This makes bismuth isooctanoate widely used in environmentally friendly rubber vulcanization.

6.2 Low volatility

Bismuth isooctanoate has low volatility and does not release harmful gases during production and use, reducing pollution to the atmospheric environment.

6.3 Biodegradability

Bismuth isooctanoate has certain biodegradability in the natural environment and will not accumulate in the environment for a long time, reducing pollution to soil and water bodies.

6.4 Environmentally Friendly Catalysts

As an environmentally friendly catalyst, bismuth isooctanoate meets the requirements of green chemistry and sustainable development. By replacing traditional toxic catalysts, environmental risks in the rubber vulcanization process can be significantly reduced.

7. Future development trends

7.1 Greening

As environmental protection regulations become increasingly strict, greening will become an important development direction in the field of rubber vulcanization. As a low-toxic, low-volatility catalyst, bismuth isooctanoate will be more widely used in green rubber vulcanization. Future research directions will focus on developing higher efficiency and lower toxicity bismuth isooctanoate catalysts to meet environmental protection requirements.

7.2 High performance

As market demand continues to increase, the demand for high-performance rubber will continue to increase. Bismuth isooctanoate has significant advantages in improving the properties of rubber. Future research directions will focus on the development of new bismuth isooctanoate catalysts to further improve the comprehensive properties of rubber.

7.3 Functionalization

Functional rubber refers to rubber with special functions, such as antibacterial, antifouling, self-cleaning, etc. The application of bismuth isooctanoate in functionalized rubber will be an important development direction. By combining it with other functional additives, rubber products with multiple functions can be developed.

7.4 Intelligence

Intelligent rubber refers to rubber that can respond to changes in the external environment and automatically adjust its performance. The application of bismuth isooctanoate in intelligent rubber will be an important development direction. Through combined use with smart materials, rubber products that can automatically adjust their properties can be developed, such as temperature-sensitive rubber, photosensitive rubber, etc.

7.5 Nanotechnology

The application of nanotechnology in rubber will be an important development direction. By combining bismuth isooctanoate with nanomaterials, nanorubbers with higher performance can be developed. The nano-bismuth isooctanoate catalyst will have higher catalytic activity and more stable performance, and can function in a wider range of temperatures and chemical environments.

8. Conclusion

Bismuth isooctanoate, as an efficient organometallic catalyst, shows unique advantages in the rubber vulcanization process. It can significantly accelerate the vulcanization reaction, improve the mechanical properties, heat resistance and chemical resistance of the vulcanization product, and has good environmental performance. By optimizing the amount of catalyst and reaction conditions, the catalytic performance of bismuth isooctanoate can be fully utilized and the comprehensive performance of rubber can be improved. In the future, as environmental protection regulations become increasingly stringent and market demand continues to increase, bismuth isooctanoate will show greater development potential in the directions of greening, high performance, functionalization, intelligence and nanotechnology, and will provide new opportunities for rubber vulcanization. make important contributions to the sustainable development of the field. It is hoped that the information provided in this article can help researchers and companies in related fields better understand and utilize this important catalyst and promote the continued development of the rubber vulcanization field.

Extended reading:
DABCO MP608/Delayed equilibrium catalyst

TEDA-L33B/DABCO POLYCAT/Gel catalyst

Addocat 106/TEDA-L33B/DABCO POLYCAT

3-morpholinopropylamine

Toyocat NP catalyst Tosoh

Toyocat ETS Foaming catalyst Tosoh

Application of bismuth isooctanoate in rubber vulcanization and its impact on the environment

Introduction

Rubber vulcanization is the process of transforming raw rubber into vulcanized rubber with excellent mechanical properties and durability through chemical reactions. This process is not only critical to the quality of rubber products, but also directly affects its performance in various applications. With the continuous improvement of environmental awareness, the search for efficient, low-toxic, and environmentally friendly sulfurization catalysts has become a research hotspot. As a new type of catalyst, bismuth isooctanoate has shown significant advantages in rubber vulcanization and has gradually attracted attention. This article will discuss in detail the application of bismuth isooctanoate in rubber vulcanization and its impact on the environment.

Basic properties of bismuth isooctanoate

Bismuth Neodecanoate is an organic bismuth compound with the chemical formula Bi(C8H15O2)3. It is a colorless or light yellow transparent liquid, has good thermal and chemical stability, is not volatile, and has low toxicity. These properties make it excellent in a variety of chemical reactions, especially in the rubber vulcanization process, where it is particularly widely used as a catalyst.

Application of bismuth isooctanoate in rubber vulcanization

1. Improve vulcanization efficiency

As a catalyst, bismuth isooctanoate can significantly improve the efficiency of rubber vulcanization. In the traditional rubber vulcanization process, commonly used catalysts include sulfur, zinc oxide, accelerators, etc. However, these catalysts often have problems such as slow reaction rates and long vulcanization times. The addition of bismuth isooctanoate can significantly accelerate the vulcanization reaction, shorten the vulcanization time, and improve production efficiency. Specific application examples are as follows:

Shorten the vulcanization time: During the vulcanization process of natural rubber, adding 0.1%~0.5% (mass fraction) of bismuth isooctanoate can significantly shorten the vulcanization time, from the original 30 minutes to Within 10 minutes. This not only improves production efficiency, but also reduces energy consumption and saves costs.
Increase the degree of vulcanization: Bismuth isooctanoate can also increase the degree of vulcanization of rubber, allowing it to reach a higher cross-linking density in a shorter time, thus improving the mechanical properties and durability of rubber products. . Experimental results show that vulcanized rubber containing bismuth isooctanoate has significantly improved tensile strength, tear strength and wear resistance.

2. Improve rubber properties

Bismuth isooctanoate not only improves vulcanization efficiency, but also significantly improves the properties of vulcanized rubber. This is specifically reflected in the following aspects:

Improve mechanical properties: Bismuth isooctanoate can promote the uniform cross-linking of rubber molecules and form a denser network structure, thus improving the mechanical properties of rubber. Experimental results show that the vulcanized rubber containing bismuth isooctanoate is superior to the control group without bismuth isooctanoate in terms of tensile strength, tear strength and wear resistance.
Improve heat resistance and aging resistance: Bismuth isooctanoate has certain antioxidant and UV resistance, which can delay the aging process of rubber to a certain extent and improve its heat resistance and aging resistance. Aging properties. This is especially important for rubber products used outdoors.
Improve processing performance: The addition of bismuth isooctanoate can improve the processing performance of rubber, making it easier to operate during mixing, calendering and molding processes, reducing equipment wear and improving production efficiency. .

3. Reduce VOC emissions

Environmental protection is an important direction for the development of modern industry, and bismuth isooctanoate performs well in this regard. The use of bismuth isooctanoate can significantly reduce volatile organic compound (VOC) emissions compared to traditional sulfidation catalysts. This is specifically reflected in the following aspects:

Reducing VOC emissions: Bismuth isooctanoate produces less VOC during the sulfurization process, which helps reduce environmental pollution and is in line with the development trend of green and environmental protection. Experimental data shows that VOC emissions during the production process of vulcanized rubber containing bismuth isooctanoate are reduced by approximately 50%.
Improve working environment: The low toxicity and low volatility of bismuth isooctanoate make the working environment safer and more comfortable, reducing potential threats to workers’ health.

The impact of bismuth isooctanoate on the environment

1. Reduce environmental pollution

As a low-toxic, low-volatility catalyst, bismuth isooctanoate can significantly reduce VOC emissions produced during the sulfidation process and reduce atmospheric pollution. In addition, bismuth isooctanoate degrades quickly in the natural environment, does not accumulate for a long time, and has a low risk of contaminating soil and water bodies.

2. Reduce energy consumption

Bismuth isooctanoate can significantly shorten vulcanization time, improve production efficiency, thereby reducing energy consumption. This is of great significance for reducing carbon emissions and achieving sustainable development. Experimental data shows that the energy consumption during the production process of vulcanized rubber containing bismuth isooctanoate is reduced by about 30%.

3. Improve resource utilization

The use of bismuth isooctanoate can improve the vulcanization degree and mechanical properties of rubber, extend the service life of rubber products, and reduce the generation of waste. This has a positive effect on improving resource utilization and reducing resource waste.

Application cases

1. Automobile tire manufacturing

In automobile tire manufacturing, the performance of vulcanized rubber is directly related to the safety and durability of the tire. A well-known tire manufacturerThe manufacturer introduced a vulcanization system containing bismuth isooctanoate in its production process. The results showed that the system not only significantly shortened the vulcanization time and improved production efficiency, but also significantly improved the mechanical properties and durability of the tire. The specific performance is:

Shorten the vulcanization time: The vulcanization time is shortened from the original 30 minutes to less than 10 minutes.
Improving mechanical properties: The tire’s tensile strength is increased by 20%, tear strength is increased by 30%, and wear resistance is increased by 25%.
Reducing VOC emissions: VOC emissions during the production process are reduced by 50%.

2. Industrial conveyor belt manufacturing

In industrial conveyor belt manufacturing, the performance of rubber directly affects the service life and work efficiency of the conveyor belt. A conveyor belt manufacturing company used a vulcanization system containing bismuth isooctanoate in its production process. The results showed that the system not only significantly improved the vulcanization efficiency, but also significantly improved the performance of the conveyor belt. The specific performance is:

Shorten the vulcanization time: The vulcanization time is shortened from the original 45 minutes to less than 15 minutes.
Improve mechanical properties: The tensile strength of the conveyor belt is increased by 25%, the tear strength is increased by 30%, and the wear resistance is increased by 20%.
Reducing VOC emissions: VOC emissions during the production process are reduced by 40%.

3. Rubber seal manufacturing

In the manufacturing of rubber seals, the performance of rubber directly affects the sealing effect and service life of the seal. A seal manufacturing company used a vulcanization system containing bismuth isooctanoate in its production process. The results showed that the system not only significantly improved the vulcanization efficiency, but also significantly improved the performance of the seal. The specific performance is:

Shorten the vulcanization time: The vulcanization time is shortened from the original 20 minutes to less than 8 minutes.
Improve mechanical properties: The tensile strength of the seal is increased by 20%, the tear strength is increased by 25%, and the aging resistance is increased by 30%.
Reducing VOC emissions: VOC emissions during the production process are reduced by 50%.

Conclusion

In summary, bismuth isooctanoate, as an efficient vulcanization catalyst, shows significant advantages in rubber vulcanization. It can not only significantly improve vulcanization efficiency and shorten vulcanization time, but also significantly improve the mechanical properties, heat resistance and aging resistance of vulcanized rubber. At the same time, the use of bismuth isooctanoate can significantly reduce VOC emissions, reduce environmental pollution, and improve the safety and comfort of the working environment. In the future, with the deepening of research and technological advancement, the application of bismuth isooctanoate in rubber vulcanization will be more extensive, providing stronger support for the sustainable development of the rubber industry.