Relation of the Physical Properties of the Isomeric Alkanes to Molecular Structure. Surface Tension, Specific Dispersion, and Critical Solution Temperature in Aniline

1948 ◽  
Vol 52 (6) ◽  
pp. 1082-1089 ◽  
Author(s):  
Harry Wiener
Keyword(s):  
Molecular Structure ◽  
Surface Tension ◽  
Physical Properties ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Structure Surface

System triethylamine–water: the equilibrium diagram and some physical properties

1967 ◽  
Vol 45 (10) ◽  
pp. 1089-1091 ◽  
Author(s):  
E. M. Kartzmark
Keyword(s):  
Thermal Analysis ◽  
Physical Properties ◽  
Freezing Point ◽  
Equilibrium Diagram ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Viscosity Measurements ◽  
Volume Of Mixing ◽  
Negative Volume

The freezing-point diagram, determined by the method of thermal analysis, corroborates the existence of a dihydrate, first discovered by Pickering (1). Density and viscosity measurements at 16.0 °C, slightly below the critical solution temperature of 18.3 °C, show marked non-ideality. The negative volume of mixing reaches a maximum at 50 mole % and the maximum in the viscosity (4.00 relative to water) occurs at 12 mole %.

Partially miscible liquid systems: The density, change of volume on mixing, vapor pressure, surface tension, and viscosity in the system: aniline–hexane

1968 ◽  
Vol 46 (14) ◽  
pp. 2399-2407 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
S. C. Anand ◽  
Y. Cheng ◽  
H. P. Dzikowski ◽  
...  
Keyword(s):  
Surface Tension ◽  
Vapor Pressure ◽  
Chemical Potential ◽  
Density Change ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Pressure Surface ◽  
Anomalous Viscosity ◽  
Tension Properties ◽  
Liquid Systems

The following properties have been investigated experimentally: density, change of volume on mixing, vapor pressure, surface tension, and viscosity, at temperatures above and below the critical solution temperature. The question at issue is: How does the chemical potential, or any property dependent on chemical potential, change, at constant temperature, over a range of composition, just above the critical solution temperature? In the present case, the vapor pressure and surface tension, properties directly dependent on chemical potential, are constant within the range of experimental accuracy (which, however, may not be sufficient) over a range of concentration. The viscosity is complicated by the occurrence of anomalous viscosity. The change of volume on mixing is negative, and this is usually associated with compound formation. In all other systems investigated by us, except the system triethylamine–water, ΔV is positive. We have shown elsewhere, however, that a very stable chemical compound is formed between water and triethylamine.

Thermodynamic analysis of phase separation of a thermoplastic in a variant epoxy/monoamine-diamine system: influence of epoxy molecular structure

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Joaquin Lopez ◽  
Maite Rico ◽  
Belen Montero ◽  
Carmen Ramirez
Keyword(s):  
Molecular Structure ◽  
Phase Separation ◽  
Polymerization Process ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Crosslinked Polymer ◽  
Epoxy Amine ◽  
Upper Critical Solution Temperature ◽  
Amine System ◽  
Molecular Fractionation

Abstract A thermodynamic study of phase separation induced by the polymerization process was carried out in a variant epoxy/amine system modified with polystyrene (PS) by means of a model based on the Flory-Huggins theory in which the polydispersity of components was taken into account. Modification of the epoxy/amine system was to continually change its molecular structure from a linear polymer to a highly crosslinked polymer using a monoamine and a diamine mixed in different proportions. The cloud-point curves during polymerization for five epoxy/monoamine-diamine systems with PS blends were experimentally measured. Application of the thermodynamic model led to obtaining the corresponding phase diagrams. All studied blends showed an upper critical solution temperature behavior and an increase in miscibility was observed by increasing the monoamine/diamine ratio. The polydispersity of components caused a molecular fractionation leading to a difference in the conversion of separate phases.

Densities, Excess Volumes, Surface Tensions, Viscosities, and Dielectric Constants of the Systems: Methanol–Cyclohexane, Acetone–Methanol, Acetone–Cyclohexane, and Methanol–Cyclohexane–Acetone

1972 ◽  
Vol 50 (8) ◽  
pp. 1109-1114 ◽  
Author(s):  
A. N. Campbell ◽  
S. C. Anand
Keyword(s):  
Surface Tension ◽  
Ternary System ◽  
Binary Systems ◽  
Dielectric Constants ◽  
Molecular Surface ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Constant Change ◽  
Molar Polarization ◽  
Horizontal Portion

The density, dielectric constant, change of volume on mixing, refractive index, surface tension, and viscosity of the methanol–cyclohexane system have been investigated experimentally at temperatures ranging from 25° to 50°. The same properties of the binary systems acetone–methanol and acetone–cyclohexane, as well as of the ternary system methanol–cyclohexane–acetone were determined experimentally at 25°. The critical region of the partially miscible system methanol–cyclohexane has been investigated by determining the above physical properties at temperatures above and below the critical solution temperature. A similar investigation of the ternary system has been made, isothermally at 25°, by investigating solutions lying in the neighborhood of the plait point.The surface tension or a derived function of it, viz. the molecular surface energy, does not show a horizontal portion of the isotherm in the methanol–cyclohexane system, but the ternary system does show such a constant surface tension, probably fortuitously, all along the tangential line. The viscosity exhibits anomaly.All the systems show azeotropic behavior. The methanol–cyclohexane and acetone–cyclohexane systems show marked deviations in molar polarization from linearity and this agrees with the thermodynamic data, which indicate larger than unity values for the activity coefficients of the components' behavior (1). The viscosity isotherms of all these systems give no indication of the formation of any stable compound.

Fluids and fluid properties

2018 ◽  
Author(s):  
Marcel Escudier
Keyword(s):  
Molecular Structure ◽  
Surface Tension ◽  
Shear Stress ◽  
Physical Properties ◽  
Vapour Pressure ◽  
Continuum Hypothesis ◽  
Absolute Temperature ◽  
Perfect Gas ◽  
Fluid Properties ◽  
The Continuum

In this chapter it is shown that the differences between solids, liquids, and gases have to be explained at the level of the molecular structure. The continuum hypothesis makes it possible to characterise any fluid and ultimately analyse its response to pressure difference Δ‎p and shear stress τ‎ through macroscopic physical properties, dependent only upon absolute temperature T and pressure p, which can be defined at any point in a fluid. The most important of these physical properties are density ρ‎ and viscosity μ‎, while some problems are also influenced by compressibility, vapour pressure pV, and surface tension σ‎. It is also shown that the bulk modulus of elasticity Ks is a measure of fluid compressibility which determines the speed at which sound propagates through a fluid. The perfect-gas law is introduced and an equation derived for the soundspeed c.

scholarly journals The Properties of Thermosensitive Zwitterionic Sulfobetaine NIPAM-co-DMAAPS Polymer and the Hydrogels: The Effects of Monomer Concentration on the Transition Temperature and Its Correlation with the Adsorption Behavior

2020 ◽  
Vol 20 (2) ◽  
pp. 324
Author(s):  
Eva Oktavia Ningrum ◽  
Agus Purwanto ◽  
Galuh Chynintya Rosita ◽  
Asep Bagus
Keyword(s):  
Molecular Structure ◽  
Phase Transition ◽  
Transition Temperature ◽  
Lower Critical Solution Temperature ◽  
Monomer Concentration ◽  
Adsorption Behavior ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Adsorption Amount

The properties of N-isopropylacrylamide copolymerized with N,N-dimethyl(acrylamidopropyl)ammonium propane sulfonate [poly(NIPAM-co-DMAAPS)] prepared with various monomer ratios such as transition temperature, molecular structure, viscosity were systematically investigated in water and Zn(NO3)2 solution. Poly(NIPAM-co-DMAAPS) in water and Zn(NO3)2 solution exhibited a phase transition with a lower critical solution temperature (LCST). The higher ratio of NIPAM monomer in poly(NIPAM-co-DMAAPS), the lower the LCST of the polymer. Furthermore, the transition temperature of poly(NIPAM-co-DMAAPS) with a lower NIPAM concentration were not confirmed both in water nor Zn(NO3)2 solution. The more increase the NIPAM concentration used in the preparation, the more increase the polymer viscosity. Moreover, the more increase the adsorption amount of ions onto the gel, the more increase the polymer transmittance as well.

Selective Hydrogen Bonding Controls Temperature Response of Layer-by-Layer Upper Critical Solution Temperature Micellar Assemblies

Soft Matter ◽  
2021 ◽  
Author(s):  
Aliaksei Aliakseyeu ◽  
Victoria Albright ◽  
Danielle Yarbrough ◽  
Samantha Hernandez ◽  
Qing Zhou ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Methacrylic Acid ◽  
Temperature Response ◽  
Solution Temperature ◽  
Layer By Layer ◽  
Critical Solution Temperature ◽  
Hydrogen Bonding Interactions ◽  
Upper Critical Solution Temperature ◽  
Lbl Films

This work establishes a correlation between the selectivity of hydrogen-bonding interactions and the functionality of micelle-containing layer-by-layer (LbL) assemblies. Specifically, we explore LbL films formed by assembly of poly(methacrylic acid)...

scholarly journals Thermo- and Photoresponsive Behaviors of Dual-Stimuli-Responsive Organogels Consisting of Homopolymers of Coumarin-Containing Methacrylate

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 329
Author(s):  
Seidai Okada ◽  
Eriko Sato
Keyword(s):  
Functional Group ◽  
Solution Temperature ◽  
Stimuli Responsive ◽  
Critical Solution Temperature ◽  
Equilibrium Degree ◽  
Stimuli Responsive Polymers ◽  
Responsive Polymers ◽  
Dual Functional ◽  
Wide Range ◽  
Increasing Temperature

Coumarin-containing vinyl homopolymers, such as poly(7-methacryloyloxycoumarin) (P1a) and poly(7-(2′-methacryloyloxyethoxy)coumarin) (P1b), show a lower critical solution temperature (LCST) in chloroform, which can be controlled by the [2 + 2] photochemical cycloaddition of the coumarin moiety, and they are recognized as monofunctional dual-stimuli-responsive polymers. A single functional group of monofunctional dual-stimuli-responsive polymers responds to dual stimuli and can be introduced more uniformly and densely than those of dual-functional dual-stimuli-responsive polymers. In this study, considering a wide range of applications, organogels consisting of P1a and P1b, i.e., P1a-gel and P1b-gel, respectively, were synthesized, and their thermo- and photoresponsive behaviors in chloroform were investigated in detail. P1a-gel and P1b-gel in a swollen state (transparent) exhibited phase separation (turbid) through a temperature jump and reached a shrunken state (transparent), i.e., an equilibrium state, over time. Moreover, the equilibrium degree of swelling decreased non-linearly with increasing temperature. Furthermore, different thermoresponsive sites were photopatterned on the organogel through the photodimerization of the coumarin unit. The organogels consisting of homopolymers of coumarin-containing methacrylate exhibited unique thermo- and photoresponsivities and behaved as monofunctional dual-stimuli-responsive organogels.

Sign in / Sign up

Export Citation Format

Share Document