title: Highly ductile multilayered films by layer-by-layer assembly of oppositely charged polyurethanes for biomedical applications.
abstract: Multilayered thin films prepared with the layer-by-layer (LBL) assembly technique are typically "brittle" composites, while many applications such as flexible electronics or biomedical devices would greatly benefit from ductile, and tough nanostructured coatings. Here we present the preparation of highly ductile multilayered films via LBL assembly of oppositely charged polyurethanes. Free-standing films were found to be robust, strong, and tough with ultimate strains as high as 680% and toughness of approximately 30 MJ/m(3). These results are at least 2 orders of magnitude greater than most LBL materials presented until today. In addition to enhanced ductility, the films showed first-order biocompatibility with animal and human cells. Multilayered structures incorporating polyurethanes open up a new research avenue into the preparation of multifunctional nanostructured films with great potential in biomedical applications.
authors.affiliation: Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Podsiadlo
authors.forename: Ming
authors.initials: M
authors.lastname: Qin
authors.forename: Meghan
authors.initials: M
authors.lastname: Cuddihy
authors.forename: Jian
authors.initials: J
authors.lastname: Zhu
authors.forename: Kevin
authors.initials: K
authors.lastname: Critchley
authors.forename: Eugene
authors.initials: E
authors.lastname: Kheng
authors.forename: Amit K
authors.initials: AK
authors.lastname: Kaushik
authors.forename: Ying
authors.initials: Y
authors.lastname: Qi
authors.forename: Hyoung-Sug
authors.initials: HS
authors.lastname: Kim
authors.forename: Si-Tae
authors.initials: ST
authors.lastname: Noh
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Arruda
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Waas
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Kotov
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D002477:Cells; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D006801:Humans; D049329:Nanostructures; D011140:Polyurethanes / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D011140:Polyurethanes