The invention relates to a heat-sensitive compound having the property of being
soluble in water below a critical temperature Tc and insoluble in water
above this temperature Tc, this property being thermally reversible,
characterized in that it comprises a first amphiphilic and thermally reversible
part corresponding to one of the following formulae (I) and (II):
##STR1##
in which i is an integer ranging from 1 to 20 and j is an integer ranging from
3 to 30.
This compound can be used to extract a chemical entity, such as uranium.
