Measurement of the Layer Compressibility Modulus of a Lamellar Mesophase with a Surface Forces Apparatus
نویسندگان
چکیده
The lamellar phase of a lyotropic solution in a confined geometry is investigated with a surface force apparatus (SFA). The measured interaction between the two SFA surfaces immersed in the mesophase is periodic, oscillatory, decaying, and discontinuous. A model is developed to account for the specific confining geometry of the SFA It is based on an array of concentric dislocation loops that allows a homeotropic alignment of the layers in a space of variable thickness. The elastic
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