Views: 0 Author: Site Editor Publish Time: 2022-01-04 Origin: Site
Dimethylformamide (DMF) is an organic compound that is used as a solvent for many products, including lacquers, pigments and dyes. Known as a volatile organic compound (VOC), DMF can endanger both humans and wildlife, but the threat is regarded as minimal because it does not occur in nature and isn't encountered by humans outside of occupational settings. Dimethylformamide is not stable when strong acids or bases are around it, and it hydrolyzes back into its original state of dimethylamine and formic acid. According to the Material Safety Data Sheet (MSDS), dimethylformamide is hazardous to health, flammable, reacts to skin on contact and poses a minimal threat of reacting with other chemicals.
Recently we showed how crystallization in microemulsions could lead directly to the most stable polymorph, thereby leapfrogging Ostwald’s rule of stages. Here we consider in more details the crystallization of mefenamic acid from dimethylformamide microemulsions. Crystallization of mefenamic acid from bulk DMF has previously been shown to produce only the metastable Form II irrespective of the supersaturation or temperature.
Dimethylformamide is a polar (hydrophilic) aprotic solvent with a high boiling point. It facilitates reactions that utilizes polar mechanisms, such as SN2 reactions. Dimethylformamide can be synthesized from methyl formate and dimethylamine or by reaction of dimethylamine with carbon monoxide. Dimethylformamide is not stable in the presence of strong bases such as sodium hydroxide or strong acids such as hydrochloric acid or sulfuric acid and is hydrolyzed back into formic acid and dimethylamine, especially at elevated temperatures.
There are several ways to form dimethylformamide, all of which involve the use of dimethylamine. For smaller production runs, dimethylamine is catalyzed with carbon monoxide and methanol or with methyl formate. In larger, laboratory-scale productions, formic acid and dimethylamine react together to create this solvent.
In contrast, we show that stable Form I can be produced from DMF microemulsions provided the lowest supersaturations that can achieve crystallization are used; these correspond to initial supersaturations that are significantly higher than those commonly used in bulk solution crystallizations, owing to the large decrease in supersaturation that occurs when a nuclei grows in a 3D-nanoconfined droplet. Increasing the supersaturation above the minimum required for crystallization leads to increasing proportions of metastable Form II crystals.
As a solvent, or a chemical that mixes with other liquids, dimethylformamide is used in the formation of many products that require a strong chemical reaction. Its high boiling point leaves it with low evaporation potential, so it will not quickly dissipate when used with other chemicals at high temperatures. Many plastics and curing processes, such as the curing done to leather, need this chemical to complete the product or process. It also can be used to break down many organic compounds.
Dimethylformamide is a neutral compound, so it does not react very well when paired with a strong acid or base. A strong base would be a compound such as sodium hydroxide, and a strong acid would be something such as sulfuric acid. When a base or acid is paired with this compound, it will revert to its two original components. This reverting process is increased if placed in a high-temperature vat.
Co-exposure of noise, DMF and TOL can affect the ambulatory blood pressure and heart rate among synthetic leather workers. Noise exposure may have obviously higher effect than chemical exposure.
Dimethylformamide is a VOC, meaning it is dangerous for humans and wildlife. It is not made in nature and isn't encountered outside certain work settings, so it is not regarded as an especially hazardous compound. Testing has shown that DMF can easily and quickly transfer from dirt to groundwater and will quickly spread through any body of water. Dimethylformamide also has been shown to cause cancer and chronically affect organs such as the lungs and heart.
The MSDS, which grades all compounds on a scale of 0 to 4 with 4 being a serious hazard, shows DMF to be a hazard. The worst risk is contacting or touching the chemical, which is rated as a 3. Both health and flammability risks earn a 2; DMF also must be stored away from high temperatures. The reactivity level is only 1, so it should not react with other compounds in an adverse way.