title: Strain analysis of a chiral smectic-A elastomer.
abstract: We present a detailed analysis of the molecular packing of a strained liquid crystal elastomer composed of chiral mesogens in the smectic-A phase. X-ray diffraction patterns of the elastomer collected over a range of orientations with respect to the x-ray beam were used to reconstruct the three-dimensional scattering intensity as a function of tensile strain. We show that the smectic domain order is preserved in these strained elastomers. Changes in the intensity within a given scattering plane are due to reorientation, and not loss, of the molecular order in directions orthogonal to the applied strain. Incorporating the physical parameters of the elastomer, a nonlinear elastic model is presented to describe the rotation of the smectic-layered domains under strain, thus providing a fundamental analysis to the mechanical response of these unique materials.
authors.affiliation: Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375, USA. christopher.spillmann@nrl.navy.mil
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Spillmann
authors.forename: John H
authors.initials: JH
authors.lastname: Konnert
authors.forename: James M
authors.initials: JM
authors.lastname: Adams
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Deschamps
authors.forename: Jawad
authors.initials: J
authors.lastname: Naciri
authors.forename: Banahalli R
authors.initials: BR
authors.lastname: Ratna
mesh_terms: D004548:Elasticity; D020724:Elastomers / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D017711:Nonlinear Dynamics; D013314:Stress, Mechanical; D014961:X-Ray Diffraction
chemical_list: D020724:Elastomers