Main chain bile acid polymers obtained via entropy-driven ring-opening metathesis are biodegradable polymers with excellent shape memory properties. X-ray scattering was used to study the conformational changes implicated in the shape memory effect of these polymers. Strain induced orientation and ordering was observed upon the drawing of the polymer films. A correlation between ordering and the shape memory performances is observed. (C) 2009 Elsevier Ltd. All rights reserved.