What is the best solvent for PVDF ?? Dimethyl sulphoxide or Dimethylacetamide??

Best solvent for in dissolving PVDF is Dimethylacetamide which is non-toxic solvent.

Dear all, the following quote is Taken from the first link référence: PVDF has a very limited solubility in common organic solvents. PVDF is typically dissolved in polar solvents such as DMF, dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP) or dimethylacetamide (DMAc). Here, PVDF was dissolved in DMF, typically at 10 wt%.

Solubility of polymers depends on many factors, where MW is the most important one. My Regards

10.1039/C3TC31774A

Dear Asmaa,

For preparation of PVDF membrane, there are different methods and solvent that you can use such as N,N-dimethylacetamide, acetone, dimethylformamide, N-methyl-2-pyrrolidone, triethylphosphate , and etc.

I have attached some articles and one thesis which every thing has been explained in details. I hope they would be useful.

Dear Asmaa Selim

There are many solvents of PVDF. Some solvents are classified as good solvents for PVDF such as DMF and CYCo. While some solvents are classified as poor solvents for it such as ACE and THF. For more details, I suggest you read this paper which demonstrated the effect of DMF, CYCo, ACE, THF, DCM, and their mixtures on the surface structures of PVDF fibers:

"Zaarour B, Zhang W, Zhu L, et al. Maneuvering surface structures of polyvinylidene fluoride nanofibers by controlling solvent systems and polymer concentration. Textile Research Journal, 2019, 89(12): 2406 2422. DOI:10.1177/0040517518792748."

Best Regards

Dr. Bilal Zaarour

Dear Asmaa Selim

The best PVDF solvent to have polar character is DMF

The best one is DMF but you should evaporate the DMF after dissolving the sample because it still stick within the material structure

DMF as it is non toxic

All mentioned solvents are more or less toxic. E.g. you can look at site WHO (www.who.int). May be NMP is less toxic than others. But it depends which facilities you have to work with organic solvents. Another issue is the importance of removal of the solvent leavings from the membrane. If the solvent is difficult to remove (like NMP) you need to find facilities/tricks to do this effectively. Acetone is easy to be removed. However the choice of the solvent is important for the membrane quality. So, when the solvent choice you need to balance toxicity/removability/membrane quality, may be something else. It depends on you)

in my experience N-methyl-2-pyrrolidone

In one sense there are no true solvents for PVDF (nothing dissolves the homopolymer crystals at room temperature):

Bottino et al:

Solubility parameters of poly(vinylidene fluoride)

Journal of Polymer Science Part B: Polymer Physics, Volume 26, Issue 4

p. 785-794

In another sense, there are over thirty "solvents" (liquids that can produce a room temperature solution if they are heated then cooled) or latent solvents or diluents for PVDF. See:

Marshall et al: On the Solubility and Stability of Polyvinylidene FluoridePolymers (Basel). 2021 May; 13(9): 1354.

Which one is best depends on what you are trying to do with it (e.g. get alpha or beta phase crystals -- higher dipole moments seem to favor beta phase although there is more to it than that). There seem to be many takes of what is toxic and what isn't. Marshall et al give green solvents (by some definitions) although some of those might warrant careful handling.