title: Bioinspired assembly of surface-roughened nanoplatelets.
abstract: Here we report a novel electrophoretic deposition technology for assembling surface-roughened inorganic nanoplatelets into ordered multilayers that mimic the brick-and-mortar nanostructure found in the nacreous layer of mollusk shells. A thin layer of sol-gel silica is coated on smooth gibbsite nanoplatelets in order to increase the surface roughness to mimic the asperity of aragonite platelets found in nacres. To avoid the severe cracking caused by the shrinkage of sol-gel silica during drying, polyelectrolyte polyethyleneimine is used to reverse the surface charge of silica-coated-gibbsite nanoplatelets and increase the adherence and strength of the electrodeposited films. Polymer nanocomposites can then be made by infiltrating the interstitials of the aligned nanoplatelet multilayers with photocurable monomer followed by photopolymerization. The resulting self-standing films are highly transparent and exhibit nearly three times higher tensile strength and one-order-of-magnitude higher toughness than those of pure polymer. The measured tensile strength agrees with that predicted by a simple shear lag model.
authors.affiliation: Department of Chemical Engineering, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Tzung-Hua
authors.initials: TH
authors.lastname: Lin
authors.forename: Wei-Han
authors.initials: WH
authors.lastname: Huang
authors.forename: In-Kook
authors.initials: IK
authors.lastname: Jun
authors.forename: Peng
authors.initials: P
authors.lastname: Jiang
mesh_terms: D000537:Aluminum Oxide / Q000138:chemical synthesis / Q000737:chemistry*; D000818:Animals; D032701:Biomimetics; D002119:Calcium Carbonate; D004563:Electrochemistry; D008974:Mollusca; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D055668:Photochemical Processes; D011094:Polyethyleneimine / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D012822:Silicon Dioxide; D011094:Polyethyleneimine; D002119:Calcium Carbonate; D000537:Aluminum Oxide