Phase behaviors of cyclic diblock copolymers

2011 ◽  
Vol 135 (17) ◽  
pp. 174902 ◽  
Author(s):  
Guojie Zhang ◽  
Zhongyong Fan ◽  
Yuliang Yang ◽  
Feng Qiu
Keyword(s):  
Diblock Copolymers ◽  
Phase Behaviors

Design, synthesis, and phase behaviors of a novel triphenylene-based side chain liquid crystalline diblock copolymer

2018 ◽  
Vol 42 (16) ◽  
pp. 13581-13588
Author(s):  
Jianfeng Ban ◽  
Lulu Pan ◽  
Bo Shi ◽  
Hailiang Zhang
Keyword(s):  
Diblock Copolymer ◽  
Liquid Crystalline ◽  
Diblock Copolymers ◽  
Weight Fraction ◽  
Side Chain ◽  
Design Synthesis ◽  
Phase Behaviors

Influence of the weight fraction of PMT6S on the phase behaviors of diblock copolymers.

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

MORPHOLOGICAL PROPERTIES OF PYRROLE AND PHENYLENE ROD–COIL DIBLOCK COPOLYMERS BY DISSIPATIVE PARTICLE DYNAMICS

2013 ◽  
Vol 12 (01) ◽  
pp. 1250100 ◽  
Author(s):  
EROL YILDIRIM ◽  
MINE YURTSEVER
Keyword(s):  
Diblock Copolymers ◽  
Dissipative Particle Dynamics ◽  
Atomic Charge ◽  
Simulation Method ◽  
Particle Dynamics ◽  
Industrial Applications ◽  
Coarse Grained ◽  
Morphological Properties ◽  
Dynamics Simulations ◽  
Phase Behaviors

Poly (para-phenylene)s (PPP) and polypyrroles (PPy) are important members of the conducting polymers. Rod–coil type diblock copolymers formed by coupling of PPP and PPy rigid blocks with polycaprolactone (PCL), polystyrene (PS) and polymethylmethacrylate (PMMA) coil blocks were modeled and morphological properties have been studied by a coarse grained simulation method at the mesoscale. Geometry optimizations and the atomic charge calculations were done quantum mechanically to obtain the input parameters for the mesoscale dynamics simulations. The accurate mixing energies and the Flory–Huggins interaction parameters between the monomers of polymers were calculated and used to study the phase behaviors and the morphologies of the copolymers as a function of type and weight percentages of the blocks by Dissipative Particle Dynamics (DPD) simulations. We showed that the methodology employed took into account not only the interaction parameter and chain length of the blocks but also the chemical structure of the polymers and it could be used to produce the phase diagram of the copolymers which has importance for the industrial applications of such materials. Among the studied copolymers, the most suitable one for thin layer applications was predicted to be PPP–b–PCL in which PPP forms lamellar and cylindrical phases in the PCL matrix if amount of PPP rod block is below 50 wt%.

Phase behaviors in a binary mixture of diblock copolymers confined between two parallel walls

2013 ◽  
Vol 22 (2) ◽  
pp. 026401 ◽  
Author(s):  
Jun-Xing Pan ◽  
Jin-Jun Zhang ◽  
Bao-Feng Wang ◽  
Hai-Shun Wu ◽  
Min-Na Sun
Keyword(s):  
Binary Mixture ◽  
Diblock Copolymers ◽  
Phase Behaviors

The phase behaviors of cylindrical diblock copolymers and rigid nanorods' mixtures

Polymer ◽  
2009 ◽  
Vol 50 (14) ◽  
pp. 3403-3410 ◽  
Author(s):  
Linli He ◽  
Linxi Zhang ◽  
Hongping Chen ◽  
Haojun Liang
Keyword(s):  
Diblock Copolymers ◽  
Phase Behaviors

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.

Equilibrium emulsification of polymer blends by diblock copolymers

1990 ◽  
Vol 51 (2) ◽  
pp. 185-200 ◽  
Author(s):  
Zhen-Gang Wang ◽  
S.A. Safran
Keyword(s):  
Polymer Blends ◽  
Diblock Copolymers

Mechanical and Structural Consequences of Associative Dynamic Cross-Linking in Acrylic Diblock Copolymers

2019 ◽  
Author(s):  
Jacob Ishibashi ◽  
Yan Fang ◽  
Julia Kalow
Keyword(s):  
Block Copolymers ◽  
Rheological Properties ◽  
Diblock Copolymers ◽  
Cross Linking ◽  
Statistical Copolymer

<p>Block copolymers are used to construct covalent adaptable networks that employ associative exchange chemistry (vitrimers). The resulting vitrimers display markedly different nanostructural, thermal and rheological properties relative to those of their statistical copolymer-derived counterparts. This study demonstrates that prepolymer sequence is a versatile strategy to modify the properties of vitrimers.</p>

Sign in / Sign up

Export Citation Format

Share Document