In my research which based on polymer electrolytes, I have do dissolve Magnesium trifluoromethanesulfonate (MgTF) in a methyl-grafted natural rubber (MG49) which already dissolved in Toluene. But I observed that the solubility is very poor. So I planed to dissolve MgTF in a different solvent first. So in this case, which will be the best solvent?