Synthesis and preparation method of stannous octoate

Stannous Octoate, as a member of organometallic compounds, is used in plastics, rubber, coatings, inks and personal care products It has attracted much attention for its wide range of applications in other industries. Its main functions include catalyst, stabilizer and antibacterial agent. This article aims to provide an overview of several common synthesis and preparation methods of stannous octoate, including traditional chemical synthesis routes and emerging electrochemical synthesis technologies.

Chemical synthesis path

Acid anhydride method

The acid anhydride method is one of the direct and commonly used synthetic routes. This method usually involves reacting a stannous salt (such as stannous chloride or stannous oxide SnO) with isooctanoic anhydride (2-Ethylhexanoic Anhydride) under appropriate solvents and conditions. During the reaction, a metathesis reaction occurs between the stannous salt and the acid anhydride to generate stannous octoate and the corresponding hydrogen halide or water. For example, stannous oxide and isooctanoic acid anhydride react under heating conditions, and then unreacted stannous oxide is removed by filtration, and residual water and unreacted isooctanoic acid are removed by distillation to obtain pure stannous octoate.

Metathesis method

Another synthetic route is the metathesis method, in which stannous salts are reacted with sodium (or potassium) isooctanoate in organic solvents to generate stannous octoate and inorganic salts. The key to this method is to ensure that the pH value and reaction conditions of the reaction system are appropriate to promote the formation of stannous octoate and inhibit the occurrence of side reactions.

Aldehyde disproportionation method

Although less common, aldehyde disproportionation is also a possible synthesis route. In this method, stannous salt reacts with isooctyl aldehyde under specific conditions to generate stannous octoate through the self-disproportionation reaction of the aldehyde. However, due to the complexity and low selectivity of the aldehyde disproportionation reaction, this method is not common in actual production.

Electrochemical synthesis technology

In recent years, electrochemical methods have received more and more attention due to their unique advantages. The electrochemical synthesis of stannous octoate is usually carried out in an electrolytic cell, using current to pass through the anode and cathode, so that the stannous salt is reduced to stannous octoate at the cathode. The advantages of this method include stable production process control, simple operation, low cost of large-scale production, and good product quality. Despite this, the industrial application of electrochemical preparation of stannous octoate has not been widely reported, and its research is still in the development stage.

Lab preparation examples

A typical method for preparing stannous octoate under laboratory conditions is to use stannous oxide and isooctanoic acid. The specific steps are as follows:

  1. In a three-necked flask equipped with mechanical stirring, a thermometer and a reflux condenser, add isooctanoic acid and stannous oxide.
  2. Under nitrogen protection, heat the mixture to about 140°C, and the reaction lasts for about 90 minutes.
  3. After the reaction is completed, filter to remove unreacted stannous oxide.
  4. Remove water and unreacted isooctanoic acid through vacuum distillation to obtain pure stannous octoate.

Conclusion

There are various synthesis and preparation methods of stannous octoate, ranging from traditional chemical synthesis pathways to emerging electrochemical technologies, each method has its own characteristics and limitations. Selecting an appropriate synthetic route requires consideration of factors such as target yield, cost-effectiveness, reaction conditions, and product purity. With the advancement of science and technology, new synthesis technologies and methods are expected to further optimize the production process of stannous octoate and improve its economic efficiency and environmental friendliness.

Extended reading:

Niax A-1Niax A-99

BDMAEE Manufacture

Toyocat NP catalyst Tosoh

Toyocat MR Gel balanced catalyst tetramethylhexamethylenediamine Tosoh

N-Acetylmorpholine

N-Ethylmorpholine

NT CAT 33LV

NT CAT ZF-10

DABCO MP608/Delayed equilibrium catalyst

TEDA-L33B/DABCO POLYCAT/Gel catalyst

Application cases of stannous octoate in coating industry

As a highly efficient catalyst, stannous octoate plays a vital role in the coatings industry, especially in polyurethane (PU), acrylic Resin and epoxy resin systems. It can significantly accelerate the curing process of coatings and improve coating properties, while showing great potential in the development of environmentally friendly coatings. The following are several typical application cases of stannous octoate in the coating industry.

Polyurethane coating

Polyurethane coatings are widely used in many fields due to their excellent physical properties, chemical resistance and decorative properties. As a catalyst for polyurethane coatings, stannous octoate can accelerate the reaction between isocyanate (NCO) and hydroxyl (OH), promote the rapid curing of the coating, and shorten the construction cycle. In two-component polyurethane coatings, the addition of stannous octoate not only speeds up the cross-linking reaction, but also helps adjust the curing rate of the coating to ensure the stability of the coating under different temperature and humidity conditions. In addition, stannous octoate can also improve the hardness, wear resistance and adhesion of the coating, and enhance the protective effect of the coating on the substrate.

Acrylic resin paint

In acrylic resin coatings, the catalytic effect of stannous octoate is equally important. It can promote the cross-linking reaction between the resin and the curing agent, form a dense network structure, and improve the weather resistance and corrosion resistance of the coating. Especially in water-based acrylic coatings, stannous octoate serves as an auxiliary catalyst and works synergistically with the main catalyst to effectively reduce VOCs (volatile organic compounds) emissions and promote the development of environmentally friendly coatings. For acrylic coatings that need to be cured at room temperature, the addition of stannous octoate is particularly critical because it can achieve rapid curing of the coating without the need for high temperatures, reducing energy consumption and improving production efficiency.

Epoxy resin coating

Epoxy resin coatings are widely used in the electronics, construction and automotive industries due to their excellent anti-corrosion properties and good electrical insulation. The application of stannous octoate in epoxy resin coatings is mainly reflected in accelerating the reaction between the curing agent and the epoxy resin, shortening the curing time, and improving the mechanical strength and chemical resistance of the coating. In some cases, stannous octoate can also be used as an auxiliary catalyst to work with amine or anhydride curing agents to improve the leveling and gloss of the coating.

Nanocomposite coating

With the development of nanotechnology, nanocomposite coatings have become a research hotspot in recent years. Stannous octoate plays a unique catalytic role in these new coatings, promoting the interfacial reaction between nanoparticles and organic polymers, enhancing the dispersion and stability of nanoparticles, and thus improving the overall performance of the coating. For example, nanocomposite coatings containing silica or carbon nanotubes can achieve a more uniform distribution of nanoparticles through the catalytic effect of stannous octoate, thereby obtaining better mechanical properties and anti-aging capabilities.

Conclusion

The application cases of stannous octoate in the coatings industry fully demonstrate its versatility and efficiency as a catalyst. Whether it is traditional coatings or emerging environmentally friendly coatings, stannous octoate can play a key role in improving the performance of coatings and meeting the special needs of different fields. With the continuous advancement of coating technology, the application scope of stannous octoate will be further expanded, bringing more innovation and development opportunities to the coating industry. At the same time, considering the chemical properties and safety issues of stannous octoate, future research needs to be devoted to developing more environmentally friendly and stable catalyst alternatives to meet increasingly stringent environmental regulations and sustainable development requirements.

Extended reading:

Niax A-1Niax A-99

BDMAEE Manufacture

Toyocat NP catalyst Tosoh

Toyocat MR Gel balanced catalyst tetramethylhexamethylenediamine Tosoh

N-Acetylmorpholine

N-Ethylmorpholine

NT CAT 33LV

NT CAT ZF-10

DABCO MP608/Delayed equilibrium catalyst

TEDA-L33B/DABCO POLYCAT/Gel catalyst

The role of pentamethyldiethylenetriamine in room temperature curing silicone rubber

Pentamethyldiethylenetriamine (PMDETA or PC5 for short) is a multifunctional amine compound that is used in many chemical It plays a role as a catalyst in the field of materials processing. During the preparation process of room temperature curing (RTV) silicone rubber, PMDETA can significantly accelerate the cross-linking reaction, thus affecting the performance and curing rate of the product.

Cure mechanism of RTV silicone rubber

Room temperature curing silicone rubber mainly cures through two mechanisms: Condensation Cure and Addition Cure. Condensed RTV silicone rubber usually uses moisture in the air as an initiator to form a three-dimensional network structure through dehydration condensation reaction between silanol groups (Si-OH). Addition RTV silicone rubber relies on the addition reaction between hydrogen-containing siloxane and siloxane containing unsaturated bonds. This process requires the participation of a platinum catalyst.

The role of PMDETA

In the curing of condensation-type RTV silicone rubber, the role of PMDETA is to promote the dehydration condensation reaction between silanol groups and accelerate the curing process. Since PMDETA has multiple active amine groups, they can serve as Lewis bases, providing electron pairs to stabilize the transition state, reduce the reaction activation energy, and thus increase the reaction rate. In addition, PMDETA can also react with the generated by-products (such as water) to reduce the inhibitory effect of water on the reaction and ensure a more thorough and uniform curing process.

Catalytic efficiency and application advantages

PMDETA’s high catalytic efficiency and selectivity make it an ideal additive for room temperature curing silicone rubber. Compared with other amine catalysts, PMDETA can achieve efficient curing effects at lower concentrations, which not only reduces costs but also reduces performance problems caused by excess catalyst residue. For example, excess catalyst may cause the silicone rubber to increase in hardness, decrease in elasticity, or generate bubbles during the curing process, affecting the aesthetics and functionality of the product.

Control curing conditions

The addition of PMDETA allows manufacturers to better control curing conditions, including curing time, temperature sensitivity and the effects of ambient humidity. This is particularly important for industrial applications that need to operate under specific conditions, such as in electronic packaging, automotive sealing, building joint filling, etc., where room temperature curing silicone rubber must cure quickly in a limited space without affecting its surrounding components.

Conclusion

Pentamethyldiethylenetriamine, as a high-performance catalyst, is crucial for the preparation of room temperature curing silicone rubber. It can not only accelerate the curing process, but also improve the controllability of curing conditions, reduce the generation of by-products, and improve the quality and performance of silicone rubber products. By finely adjusting the amount of PMDETA added, manufacturers can optimize the curing properties of silicone rubber for different application scenarios to meet diverse needs.

Extended reading:

CAS:2212-32-0 – Manufacturer of N,N-Dicyclohexylmethylamine and N,N-Dimethylcyclohexylamine – Shanghai Ohans Co., LTD

N,N-Dicyclohexylmethylamine – Manufacturer of N,N-Dicyclohexylmethylamine and N,N-Dimethylcyclohexylamine – Shanghai Ohans Co ., LTD

bismuth neodecanoate/CAS 251-964-6 – Amine Catalysts (newtopchem.com)

stannous neodecanoate catalysts – Amine Catalysts (newtopchem.com)

polyurethane tertiary amine catalyst/Dabco 2039 catalyst – Amine Catalysts (newtopchem.com)

DMCHA – morpholine

N-Methylmorpholine – morpholine

Polycat 41 catalyst CAS10294-43-5 Evonik Germany – BDMAEE

Polycat DBU catalyst CAS6674-22-2 Evonik Germany – BDMAEE