Sharp Crossover of the Susceptibility in Polymer Solutions near the Critical Demixing Point

Journal Article · Sun Nov 30 23:00:00 EST 1997 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.79.5266· OSTI ID:664579

Melnichenko, Y B; Wignall, G D ^[1]; Anisimov, M A; Povodyrev, A A; Sengers, J V ^[2]; Van Hook, W A ^[3]

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1. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393 (United States)
2. Institute for Physical Science and Technology and Department of Chemical Engineering, University of Maryland, College Park, Maryland 20742 (United States)
3. Department of Chemistry, University of Tennessee, Tennessee 37996 (United States)

We have observed a sharp and nonmonotonic crossover of the susceptibility (osmotic compressibility) from mean-field to Ising critical behavior in semidilute solutions of polystyrene in deuterocyclohexane as the temperature decreases from the {Theta} region down to the critical temperature of the phase separation. We describe this crossover in terms of a competition between the long-range but finite intramolecular correlations of monomers in the polymer chain and the diverging correlation length of concentration fluctuations. {copyright} {ital 1997} {ital The American Physical Society}

• Research Organization: Oak Ridge National Laboratory
• DOE Contract Number: AC05-96OR22464; FG02-95ER14509; FG02-88ER45374
• OSTI ID: 664579
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 26 Vol. 79; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
66 PHYSICS
CRITICAL TEMPERATURE
INTERMOLECULAR FORCES
ISING MODEL
MAGNETIC SUSCEPTIBILITY
MEAN-FIELD THEORY
NEUTRON DIFFRACTION
PHASE TRANSFORMATIONS
POLYMERS
POLYSTYRENE
SOLUTIONS