Dynamics of the Most Probable Composition Fluctuations of “Real” Diblock Copolymers near the Ordering Transition

2001 ◽  
Vol 34 (7) ◽  
pp. 2156-2171 ◽  
Author(s):  
K. Chrissopoulou ◽  
V. A. Pryamitsyn ◽  
S. H. Anastasiadis ◽  
G. Fytas ◽  
A. N. Semenov ◽  
...  
Keyword(s):  
Diblock Copolymers ◽  
Composition Fluctuations ◽  
Ordering Transition

Intermediate Wavelength Composition Fluctuations in Diblock Copolymers:  Modification of the Diffusive Mode near the Ordering Transition

2002 ◽  
Vol 35 (2) ◽  
pp. 522-528 ◽  
Author(s):  
K. Chrissopoulou ◽  
L. Papoutsakis ◽  
S. H. Anastasiadis ◽  
G. Fytas ◽  
G. Fleischer ◽  
...  
Keyword(s):  
Diblock Copolymers ◽  
Composition Fluctuations ◽  
Ordering Transition

Dynamics of Composition Fluctuations in Diblock Copolymer Solutions Far from and Near to the Ordering Transition

1994 ◽  
Vol 27 (17) ◽  
pp. 4762-4773 ◽  
Author(s):  
T. Jian ◽  
S. H. Anastasiadis ◽  
A. N. Semenov ◽  
G. Fytas ◽  
K. Adachi ◽  
...  
Keyword(s):  
Diblock Copolymer ◽  
Composition Fluctuations ◽  
Ordering Transition

Pressure and Temperature Effects in Homopolymer Blends and Diblock Copolymers

1997 ◽  
Vol 30 (5) ◽  
pp. 696-701 ◽  
Author(s):  
H. Frielinghaus ◽  
D. Schwahn ◽  
K. Mortensen ◽  
L. Willner ◽  
K. Almdal
Keyword(s):  
Interaction Parameter ◽  
Diblock Copolymers ◽  
Mean Field ◽  
Three Dimensional ◽  
Thermal Fluctuation ◽  
Thermal Fluctuations ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Phase Boundaries ◽  
Composition Fluctuations

Thermal composition fluctuations in a homogeneous binary polymer blend and in a diblock copolymer were measured by small-angle neutron scattering as a function of temperature and pressure. The experimental data were analyzed with theoretical expressions, including the important effect of thermal fluctuations. Phase boundaries, the Flory–Huggins interaction parameter and the Ginzburg number were obtained. The packing of the molecules changes with pressure. Therefore, the degree of thermal fluctuation as a function of packing and temperature was studied. While in polymer blends packing leads, in some respects, to a universal behaviour, such behaviour is not found in diblock copolymers. It is shown that the Ginzburg number decreases with pressure sensitively in blends, while it is constant in diblock copolymers. The Ginzburg number is an estimation of the transition between the universality classes of the `mean-field' approximation and the three-dimensional Ising model. The phase boundaries in blends increase with pressure, while the phase boundary of the studied block copolymer shows an unusual shape: with increasing pressure it first decreases and then increases. Its origin is an increase of the entropic and of the enthalpic parts, respectively, of the Flory–Huggins interaction parameter.

Effect of composition fluctuations on tracer diffusion in symmetric diblock copolymers

1998 ◽  
Vol 108 (11) ◽  
pp. 4634-4639 ◽  
Author(s):  
Rangaramanujam M. Kannan ◽  
Jie Su ◽  
Timothy P. Lodge
Keyword(s):  
Diblock Copolymers ◽  
Tracer Diffusion ◽  
Composition Fluctuations

Chain trapping in diblock copolymers near the ordering transition

2000 ◽  
Vol 51 (1) ◽  
pp. 68-74 ◽  
Author(s):  
S. H Anastasiadis ◽  
F Rittig ◽  
K Chrissopoulou ◽  
G Fleischer ◽  
G Fytas ◽  
...  
Keyword(s):  
Diblock Copolymers ◽  
Ordering Transition

Interdiffusion and Composition Polydispersity in Diblock Copolymers above the Ordering Transition

1995 ◽  
Vol 28 (7) ◽  
pp. 2439-2449 ◽  
Author(s):  
T. Jian ◽  
S. H. Anastasiadis ◽  
A. N. Semenov ◽  
G. Fytas ◽  
G. Fleischer ◽  
...  
Keyword(s):  
Diblock Copolymers ◽  
Ordering Transition

Dynamics of Composition Fluctuations in Diblock Copolymer Melts above the Ordering Transition

1994 ◽  
Vol 27 (15) ◽  
pp. 4335-4343 ◽  
Author(s):  
S. Vogt ◽  
S. H. Anastasiadis ◽  
G. Fytas ◽  
E. W. Fischer
Keyword(s):  
Diblock Copolymer ◽  
Copolymer Melts ◽  
Composition Fluctuations ◽  
Ordering Transition

Rich Dynamics in Diblock Copolymers

2004 ◽  
Vol 856 ◽  
Author(s):  
G. Fytas
Keyword(s):  
Phase Diagram ◽  
Structure Factor ◽  
Diblock Copolymers ◽  
Photon Correlation Spectroscopy ◽  
Dynamic Structure ◽  
High Molecular Mass ◽  
Correlation Spectroscopy ◽  
Dynamic Structure Factor ◽  
Photon Correlation ◽  
Composition Fluctuations

ABSTRACTThe dynamic structure factor S(q, t) of ultra-high molecular mass diblock copolymers BC in a common solvent was systematically investigated by photon correlation spectroscopy in different regimes of the phase diagram. Through proper probing of the composition fluctuations in symmetric and asymmetric BC the different relaxation mechanisms were identified and the influence of the disorder to order (ODT) transition was assessed. In the disordered regime, S(q, t) sensitively depends on the composition polydispersity of BC and the proximity to ODT complementing the real phase morphology of BC. The dynamic response of BC is therefore predictable.

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