Different inorganic salts

including NaSCN

NaCl

MgCl

2

and Na

2

SO

4

were added into the aqueous solution containing poly(

ε

-caprolactone)-

b

-poly(ethylene oxide) (PCL-

b

-PEO) semicrystalline micelles. The effects of inorganic salt on the micellar size and morphology were investigated with TEM and DLS. It is found that addition of NaSCN leads to increase of the micellar size

but the micelles remain to be spherical. By contrast

the other three inorganic salts can induce sphere-to-cylinder or sphere-to-lamella transformations of the PCL-

b

-PEO semicrystalline micelles. The alteration rate of the micellar size with the time after addition of the inorganic salts decreases in the following order: Na

2

SO

4

>

NaCl ≈ MgCl

2

>

NaSCN. These results were interpreted in terms of the "salting-out" ability of the cations and anions. The anions SO

4

2−

and Cl

−

have a stronger "salting-out" ability

driving the morphological transformations of the micelles and leading to a rapid change in micellar size. By contrast

SCN

−

has a weaker salting-out" ability. The cations Na

+

and Mg

2+

may associate with the PEO blocks

leading to a "salting-out" effect as well. However

the "salting-out" ability of cations is weaker than that of SO

4

2−

and Cl

−

anions

and the "salting-out" abilities of Na

+

and Mg

2+

are similar.