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In this work, we used a molecular dynamics (MD) simulation approach to investigate the interfacial binding of boron nitride nanotubes (BNNTs) with poly[m-phenylenevinylene-co-(2,5-dioctyloxy-p-phenylenevinylene)] (PmPV), polystyrene (PS), and polythiophene (PT). Quantum partial charges of BNNT−polymer composites were determined by density functional theory (DFT) calculations and then included in MD simulations. The interaction energy between nanotubes and polymer molecules was computed, and the morphology of polymers stacked onto the surface of the nanotubes was investigated based on the dihedral angle (θ). Our results confirm that the interaction energy is strongly influenced by the specific monomer structure of polymer and nanotube radius, but the influence of temperature is likely negligible. Among the investigated polymers, PT possesses the strongest adhesion to the BNNTs, followed by PmPV and PS. Moreover, the comparison of our results for BNNT−polymer composities with those of the similar carbon nanotube (CNT)−polymer composites reveals that the BNNT−polymer interactions are much stronger, which is the most important result of this work. This finding is also in good agreement with recent experimental observations. The higher values of interaction energy of BNNT−polymer composites suggest that the BNNTs could be more efficient nanofillers than the CNTs for nanocomposite reinforcement applications. [ABSTRACT FROM AUTHOR]

The osmotic coefficients and water activities in binary solutions of water-soluble DMAM−TBAM copolymer (the abbreviation for N,N-dimethylacrylamide and t-butylacrylamide copolymer) with different molar masses were determined by isopiestic method using NaCl(aq) as the reference standard at 308.15 K. From these measurements, values of the vapor pressure of solutions were determined, and the effect of molar mass on the vapor−liquid equilibrium of DMAM−TBAM copolymer has been studied. The experimental water activities data have been correlated using the Flory−Huggins equation, the modified Flory−Huggins equation, and the Freed Flory−Huggins equation + the nonrandom two-liquid model (NRTL). Better agreement with the experimental data was obtained using the Freed Flory−Huggins equation + NRTL model. [ABSTRACT FROM AUTHOR]

The osmotic virial model and the Flory−Huggins model, with the Debye−Huckel equation as an electrostatic term, have been used to correlate the liquid−liquid equilibrium data for an aqueous solution of polyoxyethylene cetyl ether surfactant (abbreviated as Brij 58) and three inorganic salts (containing NH4H2PO4, (NH4)2HPO4, and Brij58−KH2PO4) at 298.15 K. The results have shown that the maximum absolute deviation from experimental data is less than 0.6% and 1.4% for the osmotic virial model and the Flory−Huggins theory, respectively. These models are in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

Liquid–liquid equilibrium data of three systems containing surfactant polyoxyethylene cetyl ether (with abbreviation name Brij 58) and three salts, (NH 4) 2HPO 4, NH 4H 2PO 4, and KH 2PO 4, were measured at 298.15 K. Then the binodal curves were described using two three-parameter equations and the tie lines were described using four two-parameter equations. The best equations to correlate the binodal curves and the tie lines for these systems have been reported. Additionally, the effects of the salt type on the phase diagrams have been discussed. [ABSTRACT FROM AUTHOR]

Liquid−liquid equilibrium data of polyvinylpyrrolidone K2HPO4/KH2PO4buffer were measured at (298.15, 308.15, and 318.15) K and pH 5 and pH 7. The binodal curves were described using a three-parameter equation, and the tie lines were described using the Othmer−Tobias equation together with a two-parameter equation. [ABSTRACT FROM AUTHOR]