title: Mechanics of Homeotropically Ordered Smectic-A Elastomers with Global Oblate Chain Conformation.
abstract: Smectic-A elastomers combine one-dimensional translational order of rod-like segments with the rubber elasticity of a polymer network. In recent years, detailed investigations were carried out on elastomers showing a global prolate chain conformation. In this communication, the first experiments on fluorinated SA elastomers exhibiting a global oblate chain conformation are presented, where the polymer chains are on average compressed along the layer normal of the lamellar phase structure. The mechanical anisotropy is studied by means of thermoelastic experiments and stress-strain measurements. For the first time, the layer compression modulus B of smectic elastomers is directly measured. B is significantly larger as compared to conventional low molar mass liquid crystals and decreases significantly with increasing local disorder introduced by the isotropic crosslinker.
authors.affiliation: Institut für Makromolekulare Chemie, Albert-Ludwigs Universität Freiburg, Stefan-Meier Str. 31, 79104 Freiburg, Germany. dominic.kramer@makro.uni-freiburg.de.
authors.forename: Dominic
authors.initials: D
authors.lastname: Kramer
authors.affiliation: Institut für Makromolekulare Chemie, Albert-Ludwigs Universität Freiburg, Stefan-Meier Str. 31, 79104 Freiburg, Germany.
authors.forename: Heino
authors.initials: H
authors.lastname: Finkelmann
mesh_terms: D019245:Compressive Strength; D020724:Elastomers / Q000138:chemical synthesis / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure
chemical_list: D020724:Elastomers