Morphology of Symmetric Diblock Copolymers Confined Between Two Stripe-Patterned Surfaces - Tilted Lamellae and More

2005 ◽  
Vol 14 (2) ◽  
pp. 96-108 ◽  
Author(s):  
Qiang Wang
Keyword(s):  
Diblock Copolymers ◽  
Patterned Surfaces

Self-Assembly of AB Diblock Copolymers under Confinement into Topographically Patterned Surfaces

2009 ◽  
Vol 113 (43) ◽  
pp. 14052-14061 ◽  
Author(s):  
Guang Yang ◽  
Ping Tang ◽  
Yuliang Yang ◽  
Joao T. Cabral
Keyword(s):  
Self Assembly ◽  
Diblock Copolymers ◽  
Patterned Surfaces

Adsorption of diblock copolymers on stripe-patterned surfaces

2006 ◽  
Vol 125 (15) ◽  
pp. 154701 ◽  
Author(s):  
K. Sumithra ◽  
E. Straube
Keyword(s):  
Diblock Copolymers ◽  
Patterned Surfaces

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.

Sign in / Sign up

Export Citation Format

Share Document