ON THE STRUCTURAL PROPERTIES FROM RING DIBLOCK COPOLYMERS IN BULK AND IN SOLUTION

2021 ◽  
Author(s):  
Hayat BENAHMED ◽  
Abd-El-Hamid BENSAFI
Keyword(s):  
Structural Properties ◽  
Diblock Copolymers

scholarly journals Structural Properties of Charges Diblock Copolymers Solutions

1997 ◽  
Vol 52 (2) ◽  
pp. 274-277
Author(s):  
P. Guenoun ◽  
M. Delsanti ◽  
H. T. Davis ◽  
A. Maldonado ◽  
J. W. Mays ◽  
...  
Keyword(s):  
Structural Properties ◽  
Diblock Copolymers

Microphase separation of short wormlike diblock copolymers with a finite interaction range

Soft Matter ◽  
2016 ◽  
Vol 12 (8) ◽  
pp. 2481-2490 ◽  
Author(s):  
Ying Jiang ◽  
Xinghua Zhang ◽  
Bing Miao ◽  
Dadong Yan ◽  
Jeff Z. Y. Chen
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Structural Properties ◽  
Diblock Copolymers ◽  
Microphase Separation ◽  
Low Molecular Weight ◽  
Interaction Range ◽  
High Molecular Weight Polymers

A study on the structural properties of low-molecular weight AB diblock copolymers indicates substantial deviations from the properties of high-molecular weight polymers.

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.

Newborn's Preference for Faces

1996 ◽  
Vol 1 (3) ◽  
pp. 200-205 ◽  
Author(s):  
Carlo Umiltà ◽  
Francesca Simion ◽  
Eloisa Valenza
Keyword(s):  
Visual System ◽  
Structural Properties ◽  
Sensory Properties ◽  
Human Face ◽  
System Experiment ◽  
Face Experiment

Four experiments were aimed at elucidating some aspects of the preference for facelike patterns in newborns. Experiment 1 showed a preference for a stimulus whose components were located in the correct arrangement for a human face. Experiment 2 showed a preference for stimuli that had optimal sensory properties for the newborn visual system. Experiment 3 showed that babies directed their attention to a facelike pattern even when it was presented simultaneously with a non-facelike stimulus with optimal sensory properties. Experiment 4 showed the preference for facelike patterns in the temporal hemifield but not in the nasal hemifield. It was concluded that newborns' preference for facelike patterns reflects the activity of a subcortical system which is sensitive to the structural properties of the stimulus.

Investigation of the structural properties of crystallized Fe-(Cu)-Sm-B ribbons

1998 ◽  
Vol 08 (PR2) ◽  
pp. Pr2-47-Pr2-50
Author(s):  
O. Crisan ◽  
J. M. Le Breton ◽  
F. Machizaud ◽  
A. Jianu ◽  
J. Teillet ◽  
...  
Keyword(s):  
Structural Properties

A neutron scattering investigation of the structural properties of glassforming m-toluidine confined in MCM-41

2000 ◽  
Vol 10 (PR7) ◽  
pp. Pr7-95-Pr7-98 ◽  
Author(s):  
D. Morineau ◽  
F. Casas ◽  
C. Alba-Simionesco ◽  
A. Grosman ◽  
M.-C. Bellissent-Funel ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Structural Properties ◽  
Mcm 41
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