99.9% 1 3-Dioxolane CAS 646-06-0

What is 1,3-dioxolane? What are its industrial applications?

1. What is 1,3-Dioxolane?

1,3-Dioxolane, also known as 1,3-dioxolane, ethylene glycol formal, or simply ethylene glycol formal, is a five-membered cyclic acetal formed by the condensation of ethylene glycol and formaldehyde. It is an important low-boiling-point polar solvent and polymerization monomer in industry. Its chemical formula is usually written as:

C3H6O2 (1,3-dioxacyclopentane, CAS No.: 646-06-0, EINECS No.: 211-463-5, molecular weight approx. 74.08)

It is a colorless liquid at room temperature with an ether-like odor. It is miscible with water and most organic solvents, has a boiling point of about 78°C, an extremely low flash point, and is highly flammable. Its vapor can form an explosive mixture with air, and it can ignite and explode when exposed to open flames or high heat. As a cyclic acetal, 1,3-dioxolane has chemical properties between ethers and acetals.It has low toxicity, but prolonged skin contact can cause defatting and aging. The maximum allowable concentration in air is 50 milligrams per cubic meter.

In terms of structure, 1,3-dioxolane is a cyclic acetal and is a symmetrical five membered ring containing two oxygen atoms and a methylene group. Its high polarity (of ethers) and chemical reactivity (of acetals) make it an excellent polar solvent and extractant. It is also capable of copolymerizing as a monomer . It is used as a carbonyl protecting group for aldehydes and ketones in organic chemical synthesis . This compound is a very important chemical in the fields of new energy, engineering plastics and fine chemicals, and it can play multiple roles as a solvent, a monomer and a protecting group.

Chemically, 1,3-dioxolane is acid-sensitive because it can be hydrolyzed and ring-opened in acid conditions. It may oxidize and form peroxides when stored for a long time or exposed to air. Therefore, it must be stored in a closed container, protected from light, away from fire and oxidants, and with the addition of stabilizers.

Industrial-grade 1,3-dioxolane is a product for industrial use such as lithium battery electrolytes, engineering plastic copolymerization, and extraction separation. Typical specifications are 99% or better purity. Industrial grade products are focused on the following indicators:

1.Content (purity)

The content determines the performance, copolymerization effect and solubility of the electrolyte. Industrial grade electrolytes typically contain more than 99% of the content, which is a core indicator of product specifications.

2.Moisture

Moisture has a significant impact on the performance of lithium battery electrolytes (moisture reacts with lithium salts) and is also crucial to the stability of acetals, so it must be strictly controlled.

3.acidity

Acidity is a measure of free acid content. Acetals undergo acid-catalyzed hydrolysis and ring-opening reactions, which can affect product stability and downstream applications. It must be controlled at a very low level.

4.Peroxide content

Cyclic ethers and acetals are subject to oxidation and peroxide formation upon long term storage, which is a safety hazard. They must be tested and controlled before they can be used.

5. Chromaticity (APHA)

Color impacts the appearance of downstream products. Products need to be transparent and colorless.

6. Boiling range (distillation range)

The boiling range is a measure of the purity and composition of a product. Narrow boiling range is a measure of high purity, which is especially important for solvent recovery and reuse applications.

7.Evaporation residue

Evaporation residue reflects the total amount of impurities and is crucial for electrolytes and precision applications; it must be controlled within an extremely low range.

What are the applications of industrial-grade 1,3-Dioxolane?

Industrial-grade 1,3-dioxolane, with its unique properties of "cyclic acetal, high polarity, and easy polymerization," is widely used in the fields of new energy, engineering plastics, and fine chemicals.

1. Co-solvents for lithium-ion battery electrolytes (core application)

1,3-Dioxolane is a classic ether cosolvent for lithium battery electrolytes, especially widely used in lithium-sulfur battery systems (often in combination with dimethyl ethylene glycol ether (DME)) to help improve ionic conductivity, suppress lithium dendrite growth, and enhance coulombic efficiency and cycle stability. Novel in-situ polymerized poly(1,3-dioxolane) gel electrolytes are also a hot research topic in battery research.

2. Polyoxymethylene (POM) comonomer (core application)

1,3-Dioxolane is used as a comonomer for polyoxymethylene (POM) engineering plastics. The final products are used in the automotive, electronics, general machinery, and sanitary ware industries. Copolymerization with trioxymethylene can break polymer chains and stabilize end groups, significantly improving the thermal depolymerization resistance (thermal stability) and processing performance of POM. It is a key raw material for the industrial production of polyoxymethylene.

3. Low-boiling-point solvents and extractants

1,3-Dioxolane is used as a solvent for low-boiling-point compounds, as well as an extractant for oils, waxes, dyes and fiber derivatives. It is also used to extract aromatic components from lubricating oils and other petroleum products, and is a separation solvent in petrochemicals and fine chemicals.

4. Organic synthesis solvents and carbonyl protecting groups

1,3-Dioxolane and its derivatives are used as polar solvents in organic synthesis and are also the classic acetal protecting group form of aldehyde and ketone carbonyl groups. They help to selectively protect and deprotect functional groups in multi-step synthesis and are widely used in the synthesis of fine chemicals.

5. Metal Surface Treatment and Cleaning

1,3-Dioxolane is used as a degreasing and cleaning solvent component for metal parts, helping to remove oil and processing residues, serving the metal processing and surface treatment industries.

6. Coating and adhesive solvents

1,3-Dioxolane is used as a low-boiling-point solvent in coatings, adhesives and resin formulations to help improve application performance and drying speed.

7. Other applications

With the development of the new energy and engineering plastics industries, the application scope of industrial-grade 1,3-dioxolane continues to expand, including research on novel battery systems, special polymerization reaction media, and analytical solvents.

Summarize

1,3-Dioxolane, also known as 1,3-dioxolane (ethylene glycol formaldehyde, C3H6O2, CAS No. 646-06-0, EINECS No. 211-463-5), is a colorless liquid miscible with water and most organic solvents. Its unique cyclic acetal structure makes it an important chemical in the fields of new energy, engineering plastics, and fine chemicals. In daily life, we encounter it through lithium batteries, polyoxymethylene (POM) engineering plastic products, resin wax products, and fine chemicals. In industry, 1,3-dioxolane is widely used as a cosolvent in lithium battery electrolytes (especially lithium-sulfur batteries), as a polyoxymethylene comonomer, as a low-boiling-point solvent and extractant, as a carbonyl protecting group in organic synthesis, as a metal surface cleaner, and as a solvent in coatings and adhesives. Simultaneously, its highly flammable properties require strict fire and explosion prevention measures and compliance management throughout the entire supply chain.