This paper reports the synthesis of an amphiphilic copolymer from linseed oils and its successive auto-association in water into pH-sensitive micelles. An original ATRP lipoinitiator is first designed from linseed oil in two steps. tert-butyl acrylate (tBA) polymerization is consequently initiated from this original initiator and amphiphilic copolymers are obtained after subsequent acidolysis of the PtBA block into poly(acrylic acid) (PAA). The ability of a lipid-b-PAA copolymer to auto-associate in water is finally investigated through different techniques (Fluorescence, Surface Tension, QELS). This copolymer forms well-defined micelles in acidic media with a low critical micellar concentration (cmc) of 7.6 mg L-1 and dissociates when the pH is raised above 7. (C) 2012 Elsevier Ltd. All rights reserved.