cyclohexane probably for SEBS and formic acid or Hexafluoroisopropanol (HFIP) for the nylon. Please be reminded that HFIP is highly toxic, corrosive and volatile. Formic is also not easy to work with. Resorcinol might be a better option for nylon.
Thank you for your answers. However, I want to find a solvent which dissolves nylon 6 as well as SEBS g-MA because firstly I dissolve these polymers separately then mix them up.