It is traced out a parallel between the cosmological constant problem and the polymer physics. The time evolution of the universe world line is compared with the growing of a polymer chain. An equivalent Flory free energy and a modification of it are used as a means to evaluate two versions for the “radius of gyration” of the universe. It is proposed a link between this radius of gyration and t...

For concentrated polymer solutions, the free energy of mixing can be described through a “regular solution” model, such as that set forth by Flory, for a mixture of nc polymers and ns solvent molecules. To understand how the model breaks down for lower concentrations, it will be helpful to review its essential features. It is convenient to derive such a model using a lattice construct, though t...

A self-consistent field theory that describes a part of a contour loop of a random Gaussian surface as a trajectory interacting with itself is constructed. The exponent nu characterizing the end-to-end distance is obtained by a Flory argument. The result is compared with different previous derivations and is found to agree with that of Kondev and Henley over most of the range of the roughening ...

The sorption of carbon dioxide in glassy Poly(lactic acid) (PLA) films was studied by quartz crystal microbalance (QCM) at high pressures. Two thermal treatments, melted and quenched, were performed in PLA with two different L:D contents, 80:20 and 98:2, films and compared with a third thermal protocol, annealed, and used in a previous work. The results obtained show that for pressures higher t...

Separation of aromatic/non-aromatic mixtures by membrane based pervaportion process is usually analyzed by the solution-diffusion model which assumes that a permeating component is first dissolved in the membrane and then diffuses through the membrane due to its driving force. Therefore, the separate evaluation of sorption equilibria is necessary in order to determine the controlling step in ov...

Small-angle neutron scattering (SANS) has been employed to study a blend of polystyrene and polybutadiene modified by copolymer additives. SANS data from the one-phase region approaching the phase boundary has been acquired for blends modified by random and diblock copolymers that have equal amounts of styrene and butadiene monomers as well as a random copolymer with an unequal monomer composit...

Specific heat ratio (γ), pseudo-Grüneisen parameter (Γ ), heat capacity (Cp) and effective Debye temperature (θD) for binary system of tetrahydrofuran with o-cresol and methanol respectively, were calculated using the experimentally measured densities, velocities and viscosities of the pure liquids and their mixtures over the whole composition range and at T = 293, 303, 313 K. The excess pseudo...

BACKGROUND Reducing the amount of water-soluble fermentation inhibitors like furfural is critical for downstream bio-processing steps to biofuels. A theoretical approach for tailoring absorption polymers to reduce these pretreatment contaminants would be useful for optimal bioprocess design. RESULTS Experiments were performed to measure aqueous furfural partitioning into polymer resins of 5 b...

2014 The behavior of a single, flexible polymer chain near the Flory temperature 0398 is analysed in analogy with a magnetic phase transition. The transition to a collapsed state is related to a tricritical point for the magnetic problem. A solute polymer chain expands in a good solvent, and collapses in a poor solvent [1]. By suitable changes in temperature, or in solvent composition, it is po...