title: Predictive modelling-based design and experiments for synthesis and spinning of bioinspired silk fibres.
abstract: Scalable computational modelling tools are required to guide the rational design of complex hierarchical materials with predictable functions. Here, we utilize mesoscopic modelling, integrated with genetic block copolymer synthesis and bioinspired spinning process, to demonstrate de novo materials design that incorporates chemistry, processing and material characterization. We find that intermediate hydrophobic/hydrophilic block ratios observed in natural spider silks and longer chain lengths lead to outstanding silk fibre formation. This design by nature is based on the optimal combination of protein solubility, self-assembled aggregate size and polymer network topology. The original homogeneous network structure becomes heterogeneous after spinning, enhancing the anisotropic network connectivity along the shear flow direction. Extending beyond the classical polymer theory, with insights from the percolation network model, we illustrate the direct proportionality between network conductance and fibre Young's modulus. This integrated approach provides a general path towards de novo functional network materials with enhanced mechanical properties and beyond (optical, electrical or thermal) as we have experimentally verified.
authors.affiliation: Laboratory for Atomistic and Molecular Mechanics (LAMM), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Mechanical Engineering, Materials Science and Engineering Program, Florida State University, Tallahassee, Florida 32310, USA.
authors.forename: Shangchao
authors.initials: S
authors.lastname: Lin
authors.affiliation: Laboratory for Atomistic and Molecular Mechanics (LAMM), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-338, Korea.
authors.forename: Seunghwa
authors.initials: S
authors.lastname: Ryu
authors.affiliation: Laboratory for Atomistic and Molecular Mechanics (LAMM), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: Olena
authors.initials: O
authors.lastname: Tokareva
authors.affiliation: Laboratory for Atomistic and Molecular Mechanics (LAMM), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Institute for Particle Technology, Technische Universitat Braunschweig, Braunschweig 38104, Germany.
authors.forename: Greta
authors.initials: G
authors.lastname: Gronau
authors.affiliation: Department of Biomedical Engineering and Division of Materials Science and Engineering, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Jacobsen
authors.affiliation: Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Huang
authors.affiliation: Department of Physics and Astronomy, Center for Nanoscopic Physics, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Rizzo
authors.affiliation: Department of Biomedical Engineering and Division of Materials Science and Engineering, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: David
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Physics and Astronomy, Center for Nanoscopic Physics, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: Cristian
authors.initials: C
authors.lastname: Staii
authors.affiliation: Laboratory of Bio-Inspired and Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, I-38123 Trento, Italy.|Centre for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18, I-38123 Trento, Italy.|School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
authors.forename: Nicola M
authors.initials: NM
authors.lastname: Pugno
authors.affiliation: Department of Biomedical Engineering and Division of Materials Science and Engineering, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wong
authors.affiliation: Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
authors.affiliation: Laboratory for Atomistic and Molecular Mechanics (LAMM), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Buehler
mesh_terms: D003198:Computer Simulation; D055119:Elastic Modulus; D008422:Materials Testing; D055595:Mechanical Phenomena; D008855:Microscopy, Electron, Scanning; D008962:Models, Theoretical; D011108:Polymers; D047011:Silk / Q000096:biosynthesis* / Q000737:chemistry / Q000648:ultrastructure
chemical_list: D011108:Polymers; D047011:Silk