So, you’re looking for a PDMS solvent. I bet you’re having a difficult time, and mostly finding scholarly articles that you either can’t access or that don’t actually have what you’re looking for. Well I’m going to provide some summary data for a very useful paper published in 2003 by Jessamine Ng Lee, Cheolmin Park, and George M. Whitesides.
For 38 different potential solvents, they immersed their samples of cross-linked PDMS and measured the amount of swelling. Most solvents won’t dissolve PDMS. The best solvents and the measured swelling ratios are listed below, along with a few very common, but less efficacious solvents. (Below all that are the chemicals that can completely dissolve the PDMS.)
| Solvent | Swelling Ratio |
| diisopropylamine | 2.13 |
| triethylamine | 1.58 |
| pentane | 1.44 |
| xylenes | 1.41 |
| chloroform | 1.39 |
| ether | 1.38 |
| tetrahydrofuran | 1.38 |
| hexanes | 1.35 |
| trichloroethylene | 1.34 |
| n-heptane | 1.34 |
| toluene | 1.31 |
| benzene | 1.28 |
| acetone | 1.06 |
| ethyl alcohol (ethanol) | 1.40 |
If you actually want to dissolve PDMS, the paper says that 3 different items will do it: dipropylamine, sulfuric acid (18.0 mol/L), and trifluoroacetic acid (13.4 mol/L). It also notes that it took 39 days for the dipropylamine to completely dissolve the PDMS. It is important to note that these processes may all day days or weeks to complete.
