We disolve polystyrene in n-heptan, butanone-2, ethylacetate. We avoid toxic solvent (toluene, THF,...). Viscosity of this solution is high. If I adjust n-heptan and butanone-2, the viscosity still high, but when adding ethylacetate, viscosity of this solution is decrease.
You can explaint how is solvent impact to viscosity of this solution?
My answer will be by giving 2 examples & then you adjust your solvents in the way you want.
Polystyrene is soluble in toluene & in carbon tetrachloride. Toluene has a molar mass of 92.14 g/mol & a density of 0.867 g/mL while CCl4 has a molar mass of 153.82 g/mol & a density of 1.5867 g/mol.
Dissolving the same amount of the same average molecular mass polymer in the two solvents to produce 2 solutions of the same volume will give a less viscous solution in toluene than in CCl4 . This means that viscosity will increase by increasing the molar mass & the density of the used solvent.
Mr Nizar Matar , Do you think about polar of solvent influence to dissolve of polystyrene. (CCl4 is more polarity than toluene). This characteristic is important to dissolve a compound or not?
Both of the 2 solvents, that I gave as examples, are nonpolar & polystyrene is nonpolar also. This is in line with the rule : Like Dissolves Like.
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