Quasielastic light scattering of polystyrene in diethyl malonate in semidilute concentration

Wang, C. H.; Sun, Z.; Huang, Q. R.
October 1996
Journal of Chemical Physics;10/8/1996, Vol. 105 Issue 14, p6052
Academic Journal
A detailed light scattering study of polystyrene (PS) in diethyl malonate (DEM) semidilute solution has been carried out. DEM is a theta solvent for PS at 32 °C. Dynamic light scattering measurements carried out at temperatures closed to the theta temperature show only a diffusion mode in the intensity autocorrelation function; no slow modes are found in the semidilute PS/DEM solution with concentration up to more than 18 times the overlap concentration. For this system, the mutual diffusion coefficient is found to be mainly determined by the osmotic modulus, with the solution stress modulus making a negligible contribution. A slowing down of the mutual diffusion coefficient as the temperature approaches the critical temperature (at the critical concentration) is observed. These results show that despite considerable chain entanglements existing in the semidilute/concentrated PS/DEM solution, no viscoelastic slow modes are found. These results are not in agreement with the existing literature data for the same system. The absence of the viscoelastic modes is interpreted as due to the fact that PS and DEM are isopycnic and the coupling of concentration fluctuations and the solution stress modulus is negligible for isopycnic polymer solutions, in accordance with a theory recently developed in this laboratory. © 1996 American Institute of Physics.


Related Articles

  • Electrostatic and screening effects on the dynamic aspects of polyelectrolyte solutions. Mattoussi, Hedi; Karasz, Frank E.; Langley, Kenneth H. // Journal of Chemical Physics;9/1/1990, Vol. 93 Issue 5, p3593 

    We present a quasielastic light scattering (QELS) study of a synthetic polyelectrolyte compound: poly(paraphenylene vinylene) derivative dissolved in methanol. The dynamical aspects of these solutions are found to be strongly dependent on whether or not we have added an ordinary electrolyte...

  • Rod to coil transition and aggregation in soluble polydiacetylenes: Semidilute regime. Peiffer, D. G.; Chung, T. C.; Schulz, D. N.; Agarwal, P. K.; Garner, R. T.; Kim, M. W. // Journal of Chemical Physics;10/15/1986, Vol. 85 Issue 8, p4712 

    Visible absorption, rheological measurements, polarizing light microscopy, and temperature–time dependent quasielastic light scattering was used to examine the dilute–semidilute properties of polydiacetylene solutions, specifically poly(4BCMU). A good (tetrahydrofuran) and poor...

  • Interlayer water molecules in vanadium pentoxide hydrate. IX. Anisotropic translational diffusion leading to anisotropic ac conductivity. Kittaka, Shigeharu; Yamaguchi, Toshio; Bellissent-Funel, Marie-Claire // Journal of Chemical Physics;8/14/2007, Vol. 127 Issue 6, p064705 

    The anisotropy of the dynamic properties of interlayer water molecules along the a and b axes of vanadium pentoxide hydrate, orthorhombic V2O5·nH2O, was studied using quasielastic neutron scattering (QENS) in relation to the anisotropy of the ac conductivity. The QENS spectra were analyzed...

  • Character of the thermal motion of water molecules according to the data on quasielastic incoherent scattering of slow neutrons. Bulavin, L. A.; Malomuzh, N. P.; Pankratov, K. N. // Journal of Structural Chemistry;Jan2006, Vol. 47 Issue 1, p48 

    The paper discusses the applicability of quasi-crystalline approximation to describing the thermal motion of water molecules in their normal and supercooled states. The problem is subjected to the critical analysis of experimental data on incoherent scattering of slow neutrons based on theories...

  • Quasi-elastic laser light scattering study of polyacrylamide hydrogel immersed in water and salt solutions. Sivanantham, M.; Tata, B. // Pramana: Journal of Physics;Dec2010, Vol. 75 Issue 6, p1209 

    Polyacrylamide (PAAm) hydrogels immersed in water and aqueous NaCl solutions were investigated for their structure and dynamics using static and quasi-elastic laser light scattering (QELS) techniques. Ensemble-averaged electric field correlation function f( q, t) obtained from the non-ergodic...

  • Quasielastic light scattering studies of polypeptides: evidence for chain extension in solution. BAYSAL, Bahattin M.; KARADAĞ, Çiğdem // Turkish Journal of Chemistry;Aug2013, Vol. 37 Issue 4, p480 

    Dynamic light scattering and viscosimetric methods were used to study polypeptides including polyleucine, poly (γ-benzyl-L-glutamate), poly (α-L-glutamic acid), and polyproline II. Chain extension showing rod-like and exible conformations occurred in poly(γ-benzyl-L-glutamate) and...

  • A Search for the Effects of Nuclear Matter in Backward Pion–Deuteron Quasielastic Scattering by [sup 6]Li. Abramov, B. M.; Borodin, Yu. A.; Bulychjov, S. A.; Dukhovskoı, I. A.; Krutenkova, A. P.; Kulikov, V. V.; Matsyuk, M. A.; Radkevich, I. A.; Turdakina, E. N.; Khanov, A. I. // JETP Letters;11/10/2001, Vol. 74 Issue 9, p449 

    Results of a kinematically complete experiment on backward π[sup –]d quasielastic scattering by [sup 6]Li are presented. The experiment was carried out at the ITEP 3-m magnetic spectrometer with pion beams of momenta 0.72, 0.88, and 1.28GeV/c. The Fermi-motion parameters of a...

  • Self-diffusion of potassium on ultra-thin epitaxial potassium layers. Fuhrmann, D.; Hulpke, E. // Journal of Chemical Physics;2/22/1997, Vol. 106 Issue 8, p3407 

    Focuses on the self-diffusion of potassium layers supported by a nickel substrate using quasielastic helium atom scattering. Activation energy for surface diffusion; Suggestion of a jump diffusion mechanism from the way in which the energy broadening depends on the transfer of parallel momentum.

  • Theory of quasielastic light scattering of a ternary solution consisting of two homopolymers with... Wang, C.H. // Journal of Chemical Physics;9/1/1997, Vol. 107 Issue 9, p3675 

    Explains the theory of quasielastic light scattering of a ternary solution consisting of two homopolymers with arbitrary optical, hydrodynamic and thermodynamic properties. Dynamic structure factors in concentrated solution; Solutions with one polymer isorefractive with the solvent; Bimodal...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics