A Research Gate colleague asked a question about which solvent can be used to dissolve polypropylene (PP) 3 years ago & received some good answers :

https://www.researchgate.net/post/What_solvent_can_be_used_for_the_dissolution_of_Polypropylene

I suggest either toluene or any of the isomeric xylenes : o-xylene or m-xylene. Be patient since most of the used PP is of the isotactic type so it takes time to dissolve & a hot water bath may be needed to help in dissolution.

Dear Somen

In the case of PS, you can use THF. It easily solve in THF, near the boiling point.

But in the case of PP' as dear Nizar said , there are good answers in research gate.

Thank you very much, sir for your suggestions.

I think, if you want to prepare the composite membrane from a joint solution of the components you have to try to find the above recommended solvents mixture. At the same time, you have to take into account that polyaniline can not be dissolved completely in DMF.

I used dichloromethane to dissolve composite powders of polystyrene and polyaniline doped with dodecyl benzene sulfonic acid.You can try it for your mixture.

Thank you very much sir for your valuable suggestions. I will try once again.