What Is Dimethylacetamide DMAC?
Dimethylacetamide, commonly abbreviated as DMAC and also known as N,N-dimethylacetamide, is a polar aprotic solvent with the CAS number 127-19-5. Its molecular formula is C4H9NO and its molecular weight is 87.12. DMAC is a high-boiling, oily liquid with a faint ammonia-like odor. It melts at about minus 20 degrees Celsius and boils between 164.5 and 166 degrees Celsius, and its density is about 0.937 grams per milliliter at 25 degrees Celsius. These properties make DMAC a preferred solvent for processes that run at elevated temperatures.
Exceptional Solvency for Complex Formulations
One of the main advantages of DMAC is its exceptional solvency. It dissolves a vast array of polar and non-polar compounds, ranging from high-molecular-weight polymers to active pharmaceutical ingredients. This makes it a practical choice for complex formulations and reactions in which other solvents fail to keep all components in solution. Because DMAC is fully miscible with water and with most organic solvents, formulators can blend it freely to design reaction media with the exact properties they need.
Thermal Stability and High Boiling Point
With a boiling point of about 165 degrees Celsius, DMAC performs well in high-temperature processes. Its thermal and chemical stability reduces solvent loss through evaporation and ensures consistent process control over long production runs. For manufacturers running continuous operations, the low volatility of DMAC also means less solvent is consumed, which lowers material cost and reduces the amount of solvent that must be recovered or treated.
Compatibility and Role as a DMF Alternative
DMAC offers flexibility that many traditional solvents cannot match. It is compatible with a wide range of resins, polymers, and reaction systems, and it is increasingly chosen as an alternative where N,N-dimethylformamide faces tighter regulatory scrutiny. Industries that manufacture polyurethanes, coatings, and pharmaceutical intermediates have adopted DMAC because it delivers similar dissolving power with a compliance profile that suits their requirements. Pharmaceutical and electronic grades of DMAC meet the strict impurity limits needed for active pharmaceutical ingredient synthesis and for high-purity manufacturing processes.
Key Industrial Applications of DMAC
DMAC is applied as a solvent in the wet spinning of acrylic fibres and in both wet and dry spinning processes for polyurethane-based elastane fibres, where its evaporation speed is a decisive advantage. In the pharmaceutical industry, DMAC is used as a solvent and reagent in the production of various drugs, including novel x-ray contrast media, and it participates in the manufacturing process for cephalosporin antibiotics, which are partly produced from derivatives of 7-ADCA. These applications show how one solvent can serve very different manufacturing demands.
Frequently Asked Questions
What is the CAS number of dimethylacetamide? The CAS number of N,N-dimethylacetamide is 127-19-5.
Is DMAC soluble in water? Yes, DMAC is fully miscible with water in all proportions.
What is the boiling point of DMAC? DMAC boils between about 164.5 and 166 degrees Celsius at atmospheric pressure.
Why is DMAC used in fibre production? Its high solvency, thermal stability, and controlled evaporation speed make it suitable for wet and dry spinning of acrylic and elastane fibres.
Is DMAC the same as DMF? No, DMAC is N,N-dimethylacetamide while DMF is N,N-dimethylformamide, and DMAC is often selected as an alternative to DMF in regulated applications.
What precautions are needed when handling DMAC? DMAC is classified in some jurisdictions as a reproductive toxicant, so use it with proper ventilation, protective gloves, and eye protection, and consult the safety data sheet.