99% Dibenzoylmethane CAS 120-46-7

What is dibenzoylmethane? What are its industrial applications?

1. What is Dibenzoylmethane?

Dibenzoylmethane, also known as 1,3-diphenyl-1,3-propanedione, is a β-diketone compound composed of two benzoyl groups linked to a methylene group. It is one of the most important eco-friendly auxiliary heat stabilisers in the industry of plastic additives.  Its chemical formula is usually written as:

C15H12O2 (1,3-Diphenyl-1,3-propanedione, CAS No.: 120-46-7, EINECS No.: 204-398-9, molecular weight approx. 224.26)

It is a white to light yellow crystalline powder at room temperature, with a melting point of about 78-80℃. It is readily soluble in ethanol, ether, chloroform, benzene, and alkaline solutions, but insoluble in water. The β-diketone structure (-CO-CH2-CO-) in the DBM molecule exhibits keto and enol tautomerism. The enol structure can form stable chelates with metal ions, which is the structural basis for its thermal stability, UV absorption, and metal coordination functions.

The two benzene rings in DBM molecule are conjugated with the β-diketone skeleton structurally, which confers it excellent light absorption property (especially in the ultraviolet region) and chelating ability. It can complex with metals such as calcium, zinc and barium and can also absorb ultraviolet rays to protect polymer materials. It is a functional chemical of “thermal stability + light stability + chelation”.

DBM is a chemically β-diketone compound. Chemically stable, soluble in an alkaline solution to form a salt and forms coloured chelates with metal ions. It is a green alternative of the traditional lead salt stabilisers, and shows the future direction of environmentally friendly heat stabilisers, non-toxic and environment friendly. It should be stored in an airtight, light-proof and moisture-proof environment.

PVC heat stabilisation, UV and fine chemical applications are using DBM for Industry. Common specifications are 98% or higher in content (e.g. 98%, 99%). Industrial-grade products pay more attention to the following indicators:

1.Melting points

Factory inspection routine index melting point indicates the purity and consistency of crystal form of product, must control in the designated range (about 78-80℃).

2.Moisture

The moisture content affects the product storage life and the processing performance, which needs strict control.

3. Ash (Ignition Residue)

The ash content indicates the total amount of inorganic impurities, which affect the quality of the product and the compatibility of the formulation and should be controlled within a reasonable range.

4. Appearance and colour

The product shall be white to light yellow crystalline powder, the colour will affect the transparency and appearance of the downstream PVC products.

5. Content of metal impurities

Metal impurities such as iron affect thermal stability and product colour and need to be controlled within a reasonable range.

6.Solubility.

The product should be readily soluble in solvents like ethanol and alkaline solutions, without any visible insoluble matter, for uniform dispersion of the formulation.

What are the uses of industrial-grade dibenzoylmethane?

Industrial-grade DBM, with its unique properties of "β-diketone chelation + UV absorption," is widely used in plastics additives, daily chemicals, and fine chemicals.

1. PVC auxiliary heat stabilizer (core application)

DBM is a β-diketone based auxiliary heat stabiliser friendly to the environment. Used in combination with calcium-zinc, barium-zinc and rare earth stabilisation systems, it chelates zinc ions, avoids the "zinc burning" and improves the initial colouring and black spot phenomena. It is widely used in PVC flexible and rigid products (films, profiles, pipes and fittings, wires and cables, artificial leather) and is an environment-friendly alternative to lead salt stabilisers.

2. UV absorbers and light stabilizers

DBM has the ability to absorb ultraviolet light due to its β-diketone conjugated structure. It is used as an auxiliary light stabilizer for polymer materials to help absorb ultraviolet light, delay the photoaging of plastic products, and improve the weather resistance of the products.

3. UVA absorption structure in sunscreen cosmetics (derived applications)

DBM is the parent structure of the sunscreen active ingredient avobenzone (4-tert-butyl-4'-methoxydibenzoylmethane, BMDBM). Its UVA absorption properties provide an important reference for sunscreen formulations and are an important structural basis in the field of daily chemical sunscreens.

4. Metal chelate extractants

DBM's β-diketone structure can form stable chelates with ions such as uranium, rare earth elements, and transition metals, making it suitable as an extractant for liquid-liquid extraction. This helps separate and purify metal ions from solutions, serving the fields of hydrometallurgy and nuclear chemical engineering.

5. Lanthanide luminescent complex ligands

DBM is a classic ligand for luminescent complexes of lanthanides (europium, terbium, etc.), which helps to construct highly efficient red fluorescent and luminescent materials for the research and development and preparation of fluorescent probes, display devices and anti-counterfeiting materials.

6. Organic synthesis intermediates

DBM is an important building block for the synthesis of β-diketones, used to synthesize heterocyclic compounds such as flavonoids, isoflavones, pyrazoles, and thiazoles. It is an important intermediate in the synthesis of pesticides and fine chemicals.

7. color developer

DBM forms colored chelates with metal ions, which can be used as colorimetric reagents and analytical reagents for metal ions, helping to detect metal ions qualitatively and quantitatively, and serving the field of analytical testing.

8. Metal complex catalyst precursor

Complexes formed by DBM and metals can be used as catalysts or catalyst precursors for organic reactions, helping to catalyze oxidation, addition and other reactions, serving the field of fine chemical catalysis.

9. Other applications

With the development of environmentally friendly additives and functional materials, the application scope of industrial-grade DBM continues to expand, including light-stabilized modification of resin coatings, stable formulation of PVC products such as artificial hair fibers, and special functional materials.

Summarize

Dibenzoylmethane (DBM, C15H12O2, CAS No. 120-46-7, EINECS No. 204-398-9) is a white to light yellow crystalline powder with melting point about 78-80℃. It has chelating and UV absorption functions because of its β-diketone structure, and is an important kind of environmentally friendly chemical in the fields of plastics additives and fine chemicals. It can be seen in our daily life in PVC water pipes, door and window profiles, wires and cables, artificial leather, plastic packaging, sunscreen products, fluorescent and electronic materials. DBM is widely used in industry as PVC auxiliary heat stabiliser, UV absorber and light stabiliser, UVA absorption structure of sunscreen, metal chelating extractant, lanthanide luminescent complex ligand, organic production intermediate, colour developer and metal complex catalyst. It is an environmentally friendly, versatile chemical linking the fields of "β-diketone chemistry" and "plastics additives, daily chemicals, metallurgy, and materials."