title: Identification of the elastic properties of an artificial capsule membrane with the compression test: effect of thickness.
abstract: The mechanical properties of a capsule membrane are evaluated by means of a compression experiment between two parallel plates. Since large deformations of the membrane are involved, the choice of the wall material constitutive law is essential. In this paper, we explore different classical laws to describe the behavior of the membrane and evaluate also the limit of application of the thin shell approximation. A numerical study of the compression process is performed using Abaqus software and an inverse method is used to identify the material constants of the constitutive laws. The comparison between the model predictions and experimental measurements on capsules with serum albumin-alginate membranes, indicates that the thin shell approximation is valid only for thickness to radius ratios up to 5% and that thick membranes obey non linear elastomer type constitutive laws. The Young modulus of the membrane material is found to increase non-linearly with membrane thickness, thus indicating that fabrication of thicker serum albumin-alginate walls results in capsules stiffer than expected.
authors.affiliation: Laboratoire Roberval, FRE CNRS 2833, Université de Technologie de Compiègne, BP 20529, 60205 Compiègne, France. mohamed.rachik@utc.fr
authors.forename: Mohamed
authors.initials: M
authors.lastname: Rachik
authors.forename: Dominique
authors.initials: D
authors.lastname: Barthes-Biesel
authors.forename: Muriel
authors.initials: M
authors.lastname: Carin
authors.forename: Florence
authors.initials: F
authors.lastname: Edwards-Levy
mesh_terms: D000464:Alginates / Q000737:chemistry; D000465:Algorithms; D001672:Biocompatible Materials / Q000737:chemistry*; D002214:Capsules / Q000737:chemistry*; D019245:Compressive Strength; D004548:Elasticity; D008422:Materials Testing / Q000379:methods*; D008567:Membranes, Artificial; D012709:Serum Albumin / Q000737:chemistry; D012984:Software; D013499:Surface Properties; D016474:Weight-Bearing
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D002214:Capsules; D008567:Membranes, Artificial; D012709:Serum Albumin