title: Soft-shear induced phase-separated nanoparticle string-structures in polymer thin films.
abstract: Application of shear stress has been shown to unidirectionally orient the microstructures of block copolymers and polymer blends. In the present work, we study the phase separation of a novel nanoparticle (NP)-polymer blend thin film system under shear using a soft-shear dynamic zone annealing (DZA-SS) method. The nanoparticles are densely grafted with polymer chains of chemically dissimilar composition from the matrix polymer, which induces phase separation upon thermal annealing into concentrated nanoparticle domains. We systematically examine the influence of DZA-SS translation speed and thus the effective shear rate on nanoparticle domain elongation and compare this with the counterpart binary polymer blend behavior. Unidirectionally aligned nanoparticle string-domains are fabricated in the presence of soft-shear in confined thin film geometry. We expect this DZA-SS method to be applicable to various NP-polymer blends towards unidirectionally aligned nanoparticle structures, which are important to functional nanoparticle structure fabrication.
authors.affiliation: Department of Polymer Engineering, The University of Akron, 250 S Forge St, Akron, OH 44325, USA. alamgir@uakron.edu.
authors.forename: Ren
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 152133, USA.
authors.forename: Bongjoon
authors.initials: B
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 152133, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bockstaller
authors.affiliation: Chemistry Department, Faculty of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Abdullah M
authors.initials: AM
authors.lastname: Al-Enizi
authors.affiliation: Materials Science and Technology Program, College of Arts and Sciences, Qatar University, PO Box 2713, Doha, Qatar and Polymer Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technology Applications, New Borg El-Arab City, Alexandria 21934, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Elzatahry
authors.affiliation: Department of Chemistry and Applied Science Program, University of Arkansas at Little Rock, College of Arts, Letters & Sciences, 2801 S University Avenue, Little Rock, AR 72204, USA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Berry
authors.affiliation: Department of Polymer Engineering, The University of Akron, 250 S Forge St, Akron, OH 44325, USA. alamgir@uakron.edu.
authors.forename: Alamgir
authors.initials: A
authors.lastname: Karim
mesh_terms: D006046:Gold / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D044367:Phase Transition; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D013314:Stress, Mechanical; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties
chemical_list: D011137:Polystyrenes; D013438:Sulfhydryl Compounds; D006046:Gold; D019904:Polymethyl Methacrylate