Application of dioctyltin dimercaptoacetate in plastic additives

Dioctyltin dimercaptoacetate (DBT-DOTG), as an efficient heat stabilizer and antioxidant, is widely used in the field of plastic additives. Especially in the processing and modification of polyvinyl chloride (PVC) and other polyolefin materials. Its unique mechanism of action and performance characteristics make it one of the key ingredients to improve the performance and extend the service life of plastic products. The following are several major applications of dioctyltin dimercaptoacetate in plastic additives:

1. Enhanced thermal stability

PVC materials are prone to dehydrochlorination reactions during processing and high-temperature use environments, resulting in material discoloration and reduced mechanical properties. Dioctyltin dimercaptoacetate can effectively capture the free radicals released during the degradation of PVC, prevent or delay this chain reaction, thereby significantly improving the thermal stability of PVC products. This is especially important for plastic products that need to undergo high-temperature processing during the production process, such as wire and cable insulation layers, plastic doors and windows for construction, etc.

2. Improved light stability and weather resistance

Because the dioctyltin dimercaptoacetate structure contains a thiol group, it can absorb and quench ultraviolet energy, reducing the damaging effect of ultraviolet rays on plastics, thereby improving the light stability and weather resistance of the product. This is of great significance for plastic products used outdoors, such as billboards, agricultural films, roofing materials, etc., which can effectively extend their outdoor service life and maintain good appearance and mechanical properties.

3. Improved transparency

In the production of transparent PVC products, dioctyltin dimercaptoacetate is a preferred additive because it can provide the necessary stability and protection while minimizing the impact on the transparency of the material. This is indispensable for products that require a high degree of transparency, such as transparent packaging materials, spectacle lenses, medical equipment, etc.

4. Processing performance optimization

The additive can also improve the processing properties of plastics, such as fluidity, mold release, etc. During processing, dioctyltin dimercaptoacetate can help materials better disperse and fuse, reduce processing defects, and improve production efficiency and product quality.

5. Eco-friendly alternatives

With increasingly stringent environmental regulations, the use of traditional lead salts and some toxic organotin stabilizers is being gradually restricted or banned. As a relatively low-toxic organotin stabilizer, dioctyltin dimercaptoacetate has become an ideal choice to replace these harmful substances and meets the market demand for environmentally friendly materials.

6. Composite Stabilizer Component

In practical applications, dioctyltin dimercaptoacetate is often used in combination with other additives such as phosphites, epoxy compounds, etc. to form a composite stabilizer system to further improve the overall performance and stability of plastic products with a synergistic effect.

In short, dioctyltin dimercaptoacetate plays an important role in the field of plastic additives due to its excellent stability and modification ability. Especially in the modern plastics industry that pursues high performance and environmental protection. However, its potential environmental impacts and human health risks also prompt researchers to continue to explore safer and more sustainable alternatives and technologies.

Extended reading:

NT CAT DMDEE

NT CAT PC-5

NT CAT DMP-30

NT CAT DMEA

NT CAT BDMA

DMCHA – Amine Catalysts (newtopchem.com)

Dioctyltin dilaurate (DOTDL) – Amine Catalysts (newtopchem.com)

Polycat 12 – Amine Catalysts (newtopchem.com)

N-Methylmorpholine

4-Formylmorpholine

Physical and chemical properties of dioctyltin dimercaptoacetate

Dibutyltin bis(isooctylthioglycolate), whose chemical formula is generally abbreviated as DBT-DOTG, is an organic tin compound that is widely used Stabilizer used in polyvinyl chloride (PVC) plastics, especially for the processing of transparent products, has a significant effect. It enables PVC products to maintain their physical and mechanical properties and extend their service life by providing good thermal stability, light stability and anti-aging properties. Below is a detailed description of some of the key physicochemical properties of dioctyltin dimercaptoacetate.

Physical properties

Appearance: Dioctyltin dimercaptoacetate is usually a light yellow to colorless oily liquid. This is due to its organic structural characteristics that allow it to remain liquid at room temperature.

Solubility: This compound has good solubility and is easily soluble in most organic solvents, such as esters, ethers, ketones, alcohols, aliphatic hydrocarbons, aromatic hydrocarbons and commonly used Plasticizer, but insoluble in water. This solubility characteristic is crucial for its use in polymer processing, allowing for uniform dispersion in the PVC matrix.

Density: Its relative density is approximately between 1.055 and 1.075 (measured at 30°C), which means it is lighter than water, helping to achieve uniform dispersion during certain processing processes .

Melting point and boiling point: Due to the fluidity of its molecular structure, dioctyltin dimercaptoacetate does not have a clear melting point, but has a wide solidification range. Its boiling point is relatively high, usually above hundreds of degrees Celsius. The specific value depends on experimental conditions and measurement methods.

Refractive index: The refractive index is between 1.490 and 1.500 (measured at 30°C). This parameter is of great significance for understanding its optical properties and its application in transparent products.

Viscosity: The viscosity of this compound is low, less than 90mPa·s (measured at 30°C), indicating that it has good fluidity and mixing properties during processing.

Chemical properties

Stability: Dioctyltin dimercaptoacetate is relatively stable at room temperature, but may decompose at high temperatures or in a strong alkaline environment. It has some stability to light and heat, but long-term exposure may still cause performance degradation.

Reactivity: The organotin part of this compound is sensitive to moisture in the air and may slowly hydrolyze, releasing free isooctyl thioglycolate. At the same time, the divalent tin ions contained in it can participate in coordination reactions and form stable complexes with a variety of ligands.

Toxicity and Environmental Impact: Although the information mentions “toxicity of toxic substances”, the specific toxicity level and environmental impact need to be determined based on the latest chemical safety data sheet (MSDS). Organotin compounds are generally considered toxic to aquatic life, and long-term exposure may have adverse effects on human health. Therefore, appropriate safety measures should be taken when using and handling to ensure compliance with environmental and occupational safety standards.

Application Features

In PVC processing, dioctyltin dimercaptoacetate is mainly used as a heat stabilizer, which can effectively inhibit adverse reactions caused by thermal degradation of PVC during processing and use, such as color changes and reduced mechanical properties. Its unique thiol group (-SH) provides excellent antioxidant and UV resistance, helping to improve the transparency and weather resistance of products. It is especially suitable for the production of high-end PVC products such as transparent bottles, plates, and sheets.

Conclusion

To sum up, dioctyltin dimercaptoacetate is an efficient heat stabilizer. Its unique physical and chemical properties make it widely used in the PVC industry. In particular, the field of transparent products shows broad application prospects. However, due to its potential environmental and health risks, increasingly strict regulations on its production and use have driven the industry towards research and development of safer and environmentally friendly alternatives. In the future, how to balance performance and sustainability will be an important topic for research in this field.

Extended reading:

NT CAT DMDEE

NT CAT PC-5

NT CAT DMP-30

NT CAT DMEA

NT CAT BDMA

DMCHA – Amine Catalysts (newtopchem.com)

Dioctyltin dilaurate (DOTDL) – Amine Catalysts (newtopchem.com)

Polycat 12 – Amine Catalysts (newtopchem.com)

N-Methylmorpholine</u>

4-Formylmorpholine

Preparation method of dioctyltin dimercaptoacetate

Dioctyltin dimercaptoacetate is an important organotin compound, which is widely used in plastic stabilizers, catalysts and other fields because of its excellent thermal properties. It has attracted much attention due to its stability and good processing performance. Its preparation method usually involves multi-step chemical reactions, and a typical synthesis process will be introduced in detail below.

Initial raw material preparation

The preparation of dioctyltin dimercaptoacetate first requires the preparation of a series of chemical raw materials, mainly including ethanol, concentrated hydrochloric acid, sodium chloride, C7-C8 fatty alcohol (such as isooctyl alcohol), metallic tin, hydrogen chloride gas, methyl acrylate , thioglycolic acid, benzene, 2-ethylisooctyl chloroacetate, ion exchange resin, toluene, carbonate, sodium thiosulfate and water. These raw materials play different roles in the synthesis process, such as providing reactive groups, adjusting the pH value of the reaction medium, and serving as catalysts or solvents.

Overview of preparation steps

1. Synthesis of dioctyltin dichloride

First, dioctyltin dichloride is prepared by reacting dioctyltin with hydrogen chloride in an appropriate solvent. This process is often carried out under heating conditions and requires good stirring to promote complete reaction. After the reaction is completed, pure dioctyltin dichloride is isolated by filtration or distillation.

2. Synthesis of isooctyl thioglycolate

Next, isooctyl thioglycolate is synthesized through a two-step reaction of esterification and thiolation. In the esterification stage, chloroacetic acid and isooctyl alcohol react under the action of a catalyst to form the corresponding ester. Subsequently, thiolation is carried out through the Bunte salt method to convert the ester into thioglycolic acid ester. The yield of the product in this step can reach 91.5%, and the purity reaches 98.5%.

3. Synthesis of bis(isooctyl thioglycolate) di-n-octyltin

The final step is to react dioctyltin dichloride with pre-synthesized isooctyl thioglycolate to form the target product dioctyltin dimercaptoacetate. This step is usually carried out in a four-neck flask equipped with an electric stirrer, constant pressure funnel, thermometer and condenser tube to ensure controllable reaction conditions. Add a suitable solvent to the reaction system and heat it at an appropriate temperature to replace the chlorine atom with the mercapto group of isooctyl thioglycolate to generate the final product.

Post-processing and purification

After completing the above reaction, the product needs to be post-processed and purified. This usually includes precipitation, filtration, washing to remove unreacted materials and by-products, and then further purification by vacuum distillation or column chromatography to obtain high purity dioctyltin dimercaptoacetate.

Safety and environmental considerations

When performing such chemical synthesis, strict laboratory safety practices and personal protective equipment must be worn, as organotin compounds and their precursors can be toxic. In addition, considering environmental protection, waste generated during the synthesis process should be properly disposed of to avoid environmental pollution.

Conclusion

The preparation of dioctyltin dimercaptoacetate is a complex chemical process involving a variety of chemical reactions and operating steps. By precisely controlling the reaction conditions and optimizing the synthesis route, the yield and purity of the product can be effectively improved to meet the demand for high-quality organotin compounds in different application fields. With the advancement of science and technology, more environmentally friendly and efficient synthesis methods are constantly being explored to meet the requirements of sustainable development.

Extended reading:

Extended reading:

NT CAT DMDEE

NT CAT PC-5

NT CAT DMP-30

NT CAT DMEA

NT CAT BDMA

DMCHA – Amine Catalysts (newtopchem.com)

Dioctyltin dilaurate (DOTDL) – Amine Catalysts (newtopchem.com)

Polycat 12 – Amine Catalysts (newtopchem.com)

N-Methylmorpholine

4-Formylmorpholine