Kink grain boundaries in a block copolymer lamellar phase

1997 ◽  
Vol 107 (19) ◽  
pp. 8110-8119 ◽  
Author(s):  
M. W. Matsen
Keyword(s):  
Block Copolymer ◽  
Grain Boundaries ◽  
Lamellar Phase

scholarly journals Bending elastic properties of a block copolymer-rich lamellar phase doped by a surfactant: a neutron spin-echo study

Soft Matter ◽  
2014 ◽  
Vol 10 (36) ◽  
pp. 6926-6930 ◽  
Author(s):  
H. Egger ◽  
G. H. Findenegg ◽  
O. Holderer ◽  
R. Biehl ◽  
M. Monkenbusch ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Elastic Properties ◽  
Spin Echo ◽  
Lamellar Phase ◽  
Neutron Spin ◽  
Neutron Spin Echo

T-Junction Grain Boundaries in Block Copolymer−Homopolymer Blends

2000 ◽  
Vol 33 (23) ◽  
pp. 8739-8745 ◽  
Author(s):  
Engin Burgaz ◽  
Samuel P. Gido
Keyword(s):  
Block Copolymer ◽  
Grain Boundaries ◽  
Homopolymer Blends

Shear-Induced Instability of the Lamellar Phase of a Block Copolymer

1996 ◽  
Vol 29 (7) ◽  
pp. 2652-2658 ◽  
Author(s):  
Hiroya Kodama ◽  
Masao Doi
Keyword(s):  
Block Copolymer ◽  
Lamellar Phase

scholarly journals Synthesis of a High-Coercivity FePt–Ag Nanocomposite Magnet via Block Copolymer-Templated Self-Assembly

2017 ◽  
Vol 2017 ◽  
pp. 1-5
Author(s):  
Hiroaki Wakayama ◽  
Hirotaka Yonekura
Keyword(s):  
Block Copolymer ◽  
Grain Boundaries ◽  
Self Assembly ◽  
Magnetic Particles ◽  
Domain Wall Motion ◽  
Magnetic Thin Films ◽  
High Coercivity ◽  
Fept Nanoparticles ◽  
Recording Media ◽  
Nanocomposite Magnet

Magnetic recording media are composed of magnetic thin films consisting of magnetically isolated crystallites. For practical use of magnetic particles as recording media, it will be necessary to realize high coercivity by fabricating nanocrystalline grains and forming grain boundaries with the nonmagnetic phase. In this study, a high-coercivity FePt–Ag nanocomposite magnet was synthesized by means of block copolymer-templated self-assembly. Precursors of Fe, Pt, and Ag were introduced into a polymer block, and the resulting material was oxidized and then reduced to form a nanocomposite consisting of FePt nanoparticles surrounded by a matrix of Ag. X-ray diffraction analysis revealed that the introduction of Ag did not significantly affect the crystalline ordering of the FePt. The addition of Ag increased the coercivity by 53% (from 11.1 to 17.0 kOe). Our results suggest that the grain boundaries of the nonmagnetic Ag metal acted as pinning sites, disrupting magnetic coupling between individual FePt nanocrystallites and hindering domain wall motion at an external magnetic field.

scholarly journals Grain-Boundary-Induced Alignment of Block Copolymer Thin Films

Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 103 ◽  
Author(s):  
Steven Gottlieb ◽  
Marta Fernández-Regúlez ◽  
Matteo Lorenzoni ◽  
Laura Evangelio ◽  
Francesc Perez-Murano
Keyword(s):  
Thin Films ◽  
Block Copolymer ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Direct Writing ◽  
Force Microscopy ◽  
Mechanical Removal ◽  
Atomic Force ◽  
Vertically Aligned ◽  
Critical Process

We present and discuss the capability of grain boundaries to induce order in block copolymer thin films between horizontally and vertically assembled block copolymer grains. The system we use as a proof of principle is a thermally annealed 23.4 nm full-pitch lamellar Polystyrene-block-polymethylmetacrylate (PS-b-PMMA) di-block copolymer. In this paper, grain-boundary-induced alignment is achieved by the mechanical removal of the neutral brush layer via atomic force microscopy (AFM). The concept is also confirmed by a mask-less e-beam direct writing process. An elongated grain of vertically aligned lamellae is trapped between two grains of horizontally aligned lamellae. This configuration leads to the formation of 90° twist grain boundaries. The features maintain their orientation on a characteristic length scale, which is described by the material’s correlation length ξ. As a result of an energy minimization process, the block copolymer domains in the vertically aligned grain orient perpendicularly to the grain boundary. The energy-minimizing feature is the grain boundary itself. The width of the manipulated area (e.g., the horizontally aligned grain) does not represent a critical process parameter.

Direct Imaging of the Orientational Dynamics of Block Copolymer Lamellar Phase Subjected to Shear Flow

2012 ◽  
Vol 45 (12) ◽  
pp. 5260-5272 ◽  
Author(s):  
Oleksandr O. Mykhaylyk ◽  
Andrew J. Parnell ◽  
Andrew Pryke ◽  
J. Patrick A. Fairclough
Keyword(s):  
Block Copolymer ◽  
Shear Flow ◽  
Lamellar Phase ◽  
Direct Imaging ◽  
Orientational Dynamics
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