A Comparative Experimental and Theoretical Study between Heteroarm Star and Diblock Copolymers in the Microphase Separated State

2000 ◽  
Vol 33 (17) ◽  
pp. 6330-6339 ◽  
Author(s):  
Valérie Grayer ◽  
Elena E. Dormidontova ◽  
Georges Hadziioannou ◽  
Constantinos Tsitsilianis
Keyword(s):  
Diblock Copolymers ◽  
Theoretical Study

A Theoretical Study of Phase Behaviors for Diblock Copolymers in Selective Solvents

2009 ◽  
Vol 42 (17) ◽  
pp. 6791-6798 ◽  
Author(s):  
Tongchuan Suo ◽  
Dadong Yan ◽  
Shuang Yang ◽  
An-Chang Shi
Keyword(s):  
Diblock Copolymers ◽  
Theoretical Study ◽  
Selective Solvents ◽  
Phase Behaviors

Theoretical study on tailoring symmetric and asymmetric thin films of diblock copolymers

2009 ◽  
Vol 255 (11) ◽  
pp. 5775-5780 ◽  
Author(s):  
Dapeng Cao ◽  
Xianren Zhang ◽  
Wenchuan Wang
Keyword(s):  
Thin Films ◽  
Diblock Copolymers ◽  
Theoretical Study

Microphase separation in the melts of diblock copolymers with amphiphilic blocks

Soft Matter ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. 90-101
Author(s):  
Dmitry A. Filatov ◽  
Elena N. Govorun
Keyword(s):  
Diblock Copolymer ◽  
Diblock Copolymers ◽  
Theoretical Study ◽  
Microphase Separation ◽  
Amphiphilic Polymer ◽  
Copolymer Melts

Amphiphilic polymer blocks can envelop the domains of major non-amphiphilic blocks in diblock copolymer melts: a theoretical study.

Cylindrical Micelles in Rigid-Flexible Diblock Copolymers

1991 ◽  
Vol 248 ◽  
Author(s):  
D.R.M Williams ◽  
G.H. Fredrickson
Keyword(s):  
Phase Diagram ◽  
Diblock Copolymers ◽  
Theoretical Study ◽  
Flexible Tail ◽  
Cylindrical Micelles ◽  
Rigid Rod ◽  
Spherical Micelles

AbstractWe present a theoretical study of a melt of diblock copolymers consisting of a rigid rod and a flexible tail. It is shown that in addition to the lamellax phases previously discussed, there also exist phases of “hockey puck” micelles, where the rods are packed axially into cylinders. These phases occupy most of the phase diagram previously thought to consist of monolayer lamellae. It is argued that spherical micelles probably do not exist.

Morphological behavior of compatibilized ternary blends prepared by mechanical mixing

1993 ◽  
Vol 51 ◽  
pp. 1200-1201
Author(s):  
S.D. Smith ◽  
R.J. Spontak ◽  
D.H. Melik ◽  
S.M. Buehler ◽  
K.M. Kerr ◽  
...  
Keyword(s):  
Interfacial Adhesion ◽  
Diblock Copolymers ◽  
Ternary Blends ◽  
Mechanical Mixing ◽  
Design Considerations ◽  
Covalently Bonded ◽  
Homopolymer Blends ◽  
Emulsifying Agent ◽  
Surface Active ◽  
Low Entropy

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).

Triply-periodic nanostructures in surfactant, block copolymer, and biomembrane systems, and simulation of TEMs

1993 ◽  
Vol 51 ◽  
pp. 884-885
Author(s):  
David M. Anderson ◽  
Tomas Landh
Keyword(s):  
Liquid Crystalline ◽  
Diblock Copolymers ◽  
Cubic Phase ◽  
List Type ◽  
Interpenetrating Networks ◽  
Triply Periodic ◽  
Wide Range ◽  
Bicontinuous Cubic ◽  
Phase Liquid ◽  
Dividing Surface

First discovered in surfactant-water liquid crystalline systems, so-called ‘bicontinuous cubic phases’ have the property that hydropnilic and lipophilic microdomains form interpenetrating networks conforming to cubic lattices on the scale of nanometers. Later these same structures were found in star diblock copolymers, where the simultaneous continuity of elastomeric and glassy domains gives rise to unique physical properties. Today it is well-established that the symmetry and topology of such a morphology are accurately described by one of several triply-periodic minimal surfaces, and that the interface between hydrophilic and hydrophobic, or immiscible polymer, domains is described by a triply-periodic surface of constant, nonzero mean curvature. One example of such a dividing surface is shown in figure 5.The study of these structures has become of increasing importance in the past five years for two reasons:1)Bicontinuous cubic phase liquid crystals are now being polymerized to create microporous materials with monodispersed pores and readily functionalizable porewalls; figure 3 shows a TEM from a polymerized surfactant / methylmethacrylate / water cubic phase; and2)Compelling evidence has been found that these same morphologies describe biomembrane systems in a wide range of cells.

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