Key Specs
| Solvent | Boiling Point | Dielectric Constant | Water Solubility | Flash Point |
|---|---|---|---|---|
| DMSO | 189 C | 47.2 | Miscible | 95 C |
| NMP | 202 C | 32.2 | Miscible | 91 C |
| THF | 66 C | 7.5 | 10% | -14 C |
| DMF | 153 C | 36.7 | Miscible | 58 C |
| Acetonitrile | 82 C | 37.5 | Miscible | 6 C |
| Acetone | 56 C | 20.7 | Miscible | -17 C |
| DCM | 40 C | 8.93 | 1.3% | None |
| DMAC | 166 C | 37.8 | Miscible | 70 C |
Polarity ranking: DMSO > DMF ~ Acetonitrile > DMAC > NMP > Acetone > THF > DCM.
Toxicity and Safety
DMSO: Low toxicity, but penetrates skin easily and can carry other substances through with it.
NMP / DMAC: Reproductive toxicity; restricted under EU REACH and require authorization.
DMF: Hepatotoxic and absorbed through the skin. Requires strict PPE.
DCM: IARC Group 2A carcinogen, ozone-depleting, and banned in the EU from 2025.
THF: Extremely flammable and forms explosive peroxides on storage.
Pick by Industry
Pharma and agrochemicals: DMSO for transdermal carriers and cell cryopreservation; acetonitrile for HPLC. Avoid DCM and DMF.
Lithium batteries: NMP for cathode slurry with closed-loop recovery; water-based binders are the long-term direction.
Semiconductors: DMAC for photoresist stripping; metal ion content must stay below 1 ppb.
Analytical: Acetonitrile is the default for HPLC and LC-MS. Avoid DMSO due to UV background.
Industrial cleaning: Acetone for fast drying; DCM is being replaced by supercritical CO2.
Solvents on the Way Out
DCM is controlled under the Montreal Protocol. NMP and DMAC are restricted under EU REACH Annex XVII. Worth switching to: ionic liquids, gamma-valerolactone (GVL), 2-MeTHF, ethyl lactate, supercritical CO2, and CPME.
Quick Decision Guide
High boiling point and strong polarity: DMSO. Low boiling point and fast evaporation: acetone or THF, but flammable. Analytical work: acetonitrile. Battery slurry: NMP with closed-loop recovery. EHS compliance first: prioritize low-GWP, biodegradable, non-VOC solvents.