Is DMAC (CAS 127-19-5) Soluble in Water? Miscibility and Uses

Is DMAC Soluble in Water?

Yes. N,N-Dimethylacetamide, commonly shortened to DMAC or DMA, is fully miscible with water in all proportions. The CAS number 127-19-5 identifies this dipolar aprotic solvent, which mixes with water at any ratio to form a clear, homogeneous solution without phase separation. It is equally miscible with most oxygen-containing and nitrogen-containing organic solvents, which is one reason it is regarded as one of the most versatile industrial solvents.

Full miscibility is not simply a laboratory curiosity. It allows a formulator to move continuously from a pure organic medium to an aqueous one without changing the solvent system, which gives direct control over polarity, solubility and reaction rate.

Chemical Identity and Physical Data

DMAC has a high boiling point, a low freezing point and good thermal and chemical stability, which makes it suitable for reactions that must run at elevated temperature. The combination of high polarity and a high boiling point is what sets it apart from lower boiling aprotic solvents such as acetone.

What Water Miscibility Means in Practice

Reaction media can be adjusted continuously between pure organic and fully aqueous conditions, so polarity and solubility can be tuned without swapping solvents mid-process.

Water-miscible solvents are easy to strip from a product by aqueous washing, which simplifies purification.

Production equipment, reactors and lines are cleaned with water rather than with a second organic solvent.

In fibre spinning, a polymer solution in DMAC can be coagulated in a water bath, which is the basis of acrylic fibre production by wet spinning.

Because DMAC is hygroscopic, an open container will pick up atmospheric moisture and its water content will drift, so closed handling is essential for specification control.

Main Industrial Applications

In the fibre industry, DMAC is the solvent of choice for the wet spinning of acrylic fibres and for the production of polyurethane-based elastane fibres. Its evaporation behaviour suits both wet and dry spinning processes, and the water bath coagulation step depends directly on the miscibility described above. In pharmaceuticals, DMAC serves as a solvent and as a reaction medium in the manufacture of a range of active ingredients, including contrast media used in X-ray imaging, and it participates in routes to cephalosporin antibiotics built from 7-ADCA derivatives. The same solvent supports polymer processing, high performance coatings, electronics cleaning and specialty chemical synthesis where a high-boiling polar aprotic medium is required.

Storage, Handling and Regulatory Notes

Containers must be kept tightly closed because DMAC absorbs moisture from the air, and the water content of the delivered material is normally specified and verified on the certificate of analysis. Storage in a cool, dry, well ventilated area away from strong acids, strong oxidisers and halogenated compounds is recommended, and nitrogen blanketing is good practice for long term storage.

From a regulatory standpoint, DMAC is classified in the European Union as a reproductive toxicant, and it is also absorbed through the skin. The occupational exposure limit is set at 10 ppm as an eight hour time-weighted average, with a skin notation that recognises dermal uptake. Handling therefore requires local exhaust ventilation, closed transfer where practicable, chemical-resistant gloves, eye protection and protective clothing. Work areas should be kept clean, spills absorbed immediately and disposed of as hazardous waste, and the safety data sheet should be read before the material is used in any new process.

Frequently Asked Questions

Q: Is DMAC soluble in water?
Yes. N,N-Dimethylacetamide is fully miscible with water in all proportions and forms a clear, homogeneous solution at any ratio, with no phase separation at any concentration.

Q: What is the CAS number and formula of DMAC?
The CAS number of N,N-dimethylacetamide is 127-19-5, its EINECS number is 204-826-4, and its molecular formula is C4H9NO with a molecular weight of 87.12.

Q: What are the boiling and melting points of DMAC?
DMAC boils between 164.5 and 166 degrees C and melts at about minus 20 degrees C, giving it a wide liquid range that suits high temperature reactions and cold storage alike.

Q: Why is DMAC used in acrylic fibre production?
Because a polymer solution in DMAC can be coagulated in a water bath, DMAC is the standard solvent for wet spinning of acrylic fibres and for polyurethane elastane fibres, where its evaporation rate suits both wet and dry spinning.

Q: What safety measures apply to DMAC?
DMAC is classified as a reproductive toxicant in the European Union and is absorbed through the skin. Use local exhaust ventilation, chemical-resistant gloves, eye protection and protective clothing, keep containers closed, and respect the occupational exposure limit of 10 ppm as an eight hour average.

Q: How should DMAC be stored?
Store it in tightly closed containers in a cool, dry, well ventilated area away from strong acids, oxidisers and halogenated compounds. Because it is hygroscopic, closed handling and nitrogen blanketing help keep the water content within specification.