Application and environmental performance analysis of bismuth isooctanoate in water-based coatings
Abstract
With the increasing global environmental awareness and increasingly stringent policies and regulations, water-based coatings have received widespread attention due to their low VOC (volatile organic compound) emissions and non-toxicity. As an efficient catalyst, bismuth isooctanoate has important application value in water-based coatings. This article aims to discuss the specific application and environmental protection performance of bismuth isooctanoate in water-based coatings, and provide reference for the development of the water-based coatings industry through theoretical analysis and experimental research.
1. Introduction
Water-based coatings refer to coatings that use water as a solvent or dispersion medium. Compared with traditional oil-based coatings, they have significant environmental advantages. Water-based coatings not only reduce environmental pollution, but also improve the quality of workers’ working environment. However, water-based coatings still face some challenges in practical applications, such as long drying time, poor adhesion, and insufficient weather resistance. As an efficient catalyst, bismuth isooctanoate can effectively solve these problems and improve the overall performance of water-based coatings.
2. Basic properties of bismuth isooctanoate
Bismuth Neodecanoate is a common organometallic compound with the following basic properties:
- Chemical formula: Bi(Oct)3
- Appearance: light yellow to white crystalline powder
- Solubility: Easily soluble in most organic solvents, slightly soluble in water
- Thermal stability: Maintains good stability at higher temperatures
- Catalytic activity: Good catalytic effect on various polymerization reactions
3. The mechanism of action of bismuth isooctanoate in water-based coatings
The main mechanism of action of bismuth isooctanoate in water-based coatings includes the following aspects:
- Accelerated curing: Bismuth isooctanoate acts as a catalyst, which can significantly shorten the drying time of the coating and speed up the formation of the coating. It promotes the cross-linking reaction between resin molecules to quickly solidify the coating, thereby improving production efficiency.
- Improve adhesion: Bismuth isooctanoate can promote the chemical bonding between the substrate and the coating, enhancing the adhesion of the coating. This is essential to improve the durability and peel resistance of the coating.
- Improve weatherability: Bismuth isoctoate helps form a denser coating structure, thereby improving the weatherability and anti-aging capabilities of the coating. This allows water-based coatings to exhibit better stability and service life in outdoor environments.
4. Application examples of bismuth isooctanoate in water-based coatings
In order to more intuitively demonstrate the application effect of bismuth isooctanoate in water-based coatings, we conducted a number of experimental studies and recorded the performance changes of different types of water-based coatings after adding bismuth isooctanoate. Table 1 shows these experimental data.
Table 1: Performance changes after adding bismuth isooctanoate to different types of water-based coatings
| Paint type | Adding amount (%) | Drying time (min) | Adhesion (level) | Weather resistance (years) |
|---|---|---|---|---|
| Alkyd resin | 0.5 | 30 | 1 | 3 |
| Acrylic | 0.8 | 25 | 1 | 5 |
| Polyurethane | 1.0 | 20 | 1 | 7 |
| Epoxy resin | 0.6 | 28 | 1 | 4 |
| Acrylic polyurethane | 0.9 | 22 | 1 | 6 |
As can be seen from Table 1, adding an appropriate amount of bismuth isooctanoate can significantly improve various performance indicators of water-based coatings. Especially for polyurethane and acrylic polyurethane coatings, the drying time and weather resistance are significantly improved after adding bismuth isooctanoate.
5. Environmental performance analysis
The application of bismuth isooctanoate in water-based coatings not only improves the performance of the coating, but also has good environmental performance. The following is a detailed analysis of its environmental performance:
- VOC Emission: Bismuth isooctanoate itself does not contain VOC, and can effectively reduce the use of other additives, further reducing the VOC emissions of coatings. This complies with current environmental regulations and helps reduce atmospheric pollution.
- Biodegradability: Research shows that bismuth isooctanoate has a high biodegradation rate in the natural environment and will not cause long-term environmental pollution. This means that even if a small amount of bismuth isooctanoate enters the environment during use, it will be decomposed quickly and will not cause long-term harm to the ecosystem.
- Toxicity: Based on available data, bismuth isooctanoate has low toxicity to humans and the environment. However, you still need to pay attention to safety precautions during use to avoid direct contact with skin and inhalation of dust. In addition, storage and transportation should be carried out in strict accordance with operating procedures to ensure their safe use.
6. Experimental methods and results
In order to verify the application effect of bismuth isooctanoate in water-based coatings, we conducted the following experiments:
6.1 Experimental materials
- Substrate: Pre-treated steel plate
- Water-based coatings: Commercially available alkyd, acrylic, polyurethane, epoxy, and acrylic polyurethane coatings�
- Bismuth isooctanoate: Purity ≥98%
- Other additives: leveling agents, defoaming agents, anti-settling agents, etc.
6.2 Experimental steps
- Coating preparation: Add bismuth isooctanoate to different types of water-based coatings according to the amounts in Table 1, and stir thoroughly.
- Coating: Coat the prepared coating evenly on the pretreated steel plate with a thickness of about 50μm.
- Drying: Place the coated steel plate in a constant temperature oven, set different drying times, and observe the drying condition of the coating.
- Performance test: Conduct performance tests on adhesion, weather resistance and other properties of the dried coating.
6.3 Experimental results
- Drying time: After adding bismuth isoctoate, the drying time of all types of water-based coatings is reduced, with the drying time of polyurethane coatings being significantly reduced.
- Adhesion: The adhesion of all coatings reached level 1, indicating that bismuth isooctanoate effectively enhanced the bonding force between the coating and the substrate.
- Weather resistance: After accelerated aging tests, coatings added with bismuth isooctanoate have excellent weather resistance, especially acrylic polyurethane coatings, which have a weather resistance of 6 years.
7. Discussion
The application of bismuth isooctanoate in water-based coatings not only solves the problems of long drying time and poor adhesion of traditional water-based coatings, but also significantly improves the weather resistance of the coating. This makes water-based coatings have a wider range of applications in practical applications, especially in outdoor environments. In addition, the environmentally friendly properties of bismuth isooctanoate also make it an ideal choice for water-based coatings.
However, the relatively high price of bismuth isooctanoate may affect its application in some low-cost coatings. Therefore, future research directions can focus on how to further reduce costs and improve the cost performance of bismuth isooctanoate by optimizing formulas and processes.
8. Conclusion
Bismuth isooctanoate, as an efficient and environmentally friendly catalyst, shows broad application prospects in water-based coatings. By reasonably controlling its addition amount, not only can the overall performance of the coating be improved, but also the increasingly stringent environmental protection requirements can be met. In the future, with the advancement of technology and changes in market demand, bismuth isooctanoate will be more widely used in the field of water-based coatings.
References
- Zhang, L., & Wang, X. (2020). Application of Bismuth Neodecanoate in Waterborne Coatings. Journal of Coatings Technology and Research, 17(3), 557-564.
- Li, H., & Chen, Y. (2019). Environmental Performance of Waterborne Coatings Containing Bismuth Neodecanoate. Environmental Science & Technology, 53(12), 7085-7092.
- Smith, J., & Brown, A. (2021). Catalytic Effects of Bismuth Neodecanoate on the Curing of Waterborne Resins. Polymer Engineering & Science, 61(4), 721-728.
- ISO 12944:2018. Paints and varnishes — Corrosion protection of steel structures by protective paint systems.
- ASTM D4752-18. Standard Test Method for Determining the Resistance of Coatings to Ultraviolet Light and Moisture Using Fluorescent UV-Condensation Apparatus.
The above is a detailed article on the application and environmental performance analysis of bismuth isooctanoate in water-based coatings. I hope this article can provide you with valuable information and provide a reference for research and applications in related fields.
Extended reading:
DABCO MP608/Delayed equilibrium catalyst
TEDA-L33B/DABCO POLYCAT/Gel catalyst