The interactions between C8H17(OC2H4)nSO4Na (C8E.S; n=0, 1, 3) andC8H17NC6H5Br(C8Py), C8EnS and CmH2m+2NC5H5Br (CmPy; m=10, 12, 14, 16), t-C8H17C6H4(OC2H4)9.8SO4Na (C8φE9.8S) and cmPy in micelles have been studied bysuxface tension method. The partial ternary "phase diagram" of C8EnS-C8Py-H2O andC8EnS-C12Py-H2O systems have been obtained. The results show that with the increaseof n, the interaction between C8EnS and C8Py decreases and the stability of aqueous so-lution of C8EnS-C8Py increases. With the increase of m, the interaction between C8E3Sand CmPy increases and the stability of aqueous solution of C8E3S-CmPy decreases. Theinteraction between C8φE9.8S and CmPy is strong while the aqueous so1ution of C8φE9.8S-C.Py is still very stable.
