Thermal Transitions in Polyelectrolyte Assemblies Occur via a Dehydration Mechanism

2015-09-01
Yıldırım, Erol
Lutkenhaus, Jodie L.
Sammalkorpi, Maria
Hydrated polyelectrolyte (PE) complexes and multilayers undergo a well-defined thermal transition that bears resemblance to a glass transition. By combining molecular simulations and differential scanning calorimetry (DSC) of poly(diallyldimethylammonium) (PDAC) and poly(styrenesulfonate) (PSS) multilayers, we establish for the first time that dehydration drives the thermally induced change in plasticization of the complex and in the diffusion behavior of its components. DSC experiments show that the thermal transition appears when the assemblies are hydrated in water but not in the presence of alcohols, which supports that water is required for this transition. These findings connect PE complexes more generally to thermoresponsive polymers and liquid crystal phases, which bear phase transitions driven by the (de)hydration of functional groups, thus forming a fundamental link toward an integrated understanding of the thermal response of molecular materials in aqueous environments.
ACS MACRO LETTERS

Suggestions

Thermal stimulation of aqueous volumes contained in carbon nanotubes: Experiment and modeling
Yarin, AL; Güvenç Yazıcıoğlu, Almıla; Megaridis, CM (2005-01-01)
The dynamic response, as caused by thermal stimulation, of aqueous liquid attoliter volumes contained inside multiwall carbon nanotubes is investigated theoretically and experimentally. The experiments indicate an energetically driven mechanism responsible for the dynamic multiphase fluid behavior visualized under high resolution in the transmission electron microscope. The theoretical model is formulated using a continuum approach, which combines temperature-dependent diffusion with intermolecular interact...
Reversible ionic surfactants for gold nanoparticle synthesis
Ethier, Amy L.; Hart, Emily C.; Saunders, Steven R.; Biddinger, Elizabeth J.; Fadhel, Ali Z.; Dilek Hacıhabiboğlu, Çerağ; Pollet, Pamela; Eckert, Charles A.; Liotta, Charles L. (2014-06-01)
Reversible systems such as silylamines are neutral amines that can react reversibly with CO2 to form the corresponding ammonium carbamate ionic pair. The ionic-to-neutral 'switch' capability provides an advantageous means for efficient synthesis and facile deposition of nanoparticles onto a solid support. Herein, we first illustrate the surface active/non-surface active duality of the silylamine systems with the reversible solubilization-precipitation of methyl orange from a hexane solution of the 3-(aminop...
Frequency dependence of the constitutive parameters of causal perfectly matched anisotropic absorbers
Kuzuoğlu, Mustafa (1996-12-01)
Perfectly matched layers (PML's), which are employed for mesh truncation in the finite-difference time-domain (FDTD) or in finite element methods (FEM's), can be realized by artificial anisotropic materials with properly chosen permittivity and permeability tensors. The tensor constitutive parameters must satisfy the Kramers-Kronig relationships, so that the law of causality holds. These relations are used to relate the real and imaginary parts of the constitutive parameters of the PML media to deduce the a...
Defect luminescence in some layered binary chalcogenide semiconductors
Aydinli, A; Hasanlı, Nızamı (2002-01-01)
A number of semiconductors such as GaS, GaSe, GaSSe show layered structure where intralayer bonding is strong and interlayer bonding quite weak. With bandgaps mostly in the visible and the near infrared and high crystal structure anisotropy, such semiconductors offer interesting possibilities for optoelectronic applications. In this review, we will summarize the recent developments on the photoluminescent properties of these materials such as luminescence due to donor-acceptor pair recombination. As these m...
Thermal properties of Deng-Fan-Eckart potential model using Poisson summation approach
Edet, C. O.; Okorie, U. S.; Osobonye, G.; Ikot, A. N.; Rampho, G. J.; Sever, Ramazan (Springer Science and Business Media LLC, 2020-05-01)
The Deng-Fan-Eckart potential is as good as the Morse potential in studying atomic interaction in diatomic molecules. By using the improved Pekeris-type approximation, to deal with the centrifugal term, we obtain the bound-state solutions of the radial Schrodinger equation with this adopted molecular model via the Factorization Method. With the energy equation obtained, the thermodynamic properties of some selected diatomic molecules (H-2, CO, ScN and ScF) were obtained using Poisson summation method. The u...
Citation Formats
E. Yıldırım, J. L. Lutkenhaus, and M. Sammalkorpi, “Thermal Transitions in Polyelectrolyte Assemblies Occur via a Dehydration Mechanism,” ACS MACRO LETTERS, pp. 1017–1021, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35255.