The effect of solvents on the morphology and properties of styrene-butadiene-styrene(SBS, \{Mn=\}99 575, Mw/Mn=1.3, S/B=3∶7) triblock copolymer films was studied in this paper. The solvents used in the study are: ethylmethylketone, a preferential solvent for the PS block; toluene, a non-preferential solvent for both the PS and the PB blocks; and mixed hexane/cyclohexane(2/5, in volume ratio), a preferential solvent for the PB block. The morphology of samples cast from solutions from different solvents and then stained by RuO4 was observed by TEM. Moreover, the tensile properties and deformation recovery behavior for these samples were measured and the results are explained according to the microstructures observed.
The morphology of poly(styrene ethylene/butylene styrene)(SEBS) triblock copolymer cast from heptane and toluene was studied by combining atomic force microscopy(AFM) with transmission electronics microscopy(TEM). The quantitative agreement of the results of AFM and TEM plays a key role in determining the phase attribution for the AFM images. It is confirmed that under the moderate tapping condition, the hills in AFM height images correspond to the polystyrene phase and the valleys to the rubbery phase.