SOME PROPERTIES OF PURE POLYOXYETHYLENEGLYGOL ETHERS IN SOLUTION

1961 ◽  
Vol 39 (2) ◽  
pp. 331-338 ◽  
Author(s):  
A. F. Sirianni ◽  
B. A. Gingras
Keyword(s):  
Critical Micelle Concentration ◽  
Infinite Dilution ◽  
Solution Properties ◽  
Raoult’S Law ◽  
Association Patterns ◽  
Solvation Effects ◽  
Molecular Weights ◽  
Hydrophobic Portion ◽  
Apparent Association ◽  
Raoult's Law

Solution properties of a series of hexaoxyethyleneglycol ethers having 8 to 16 carbon atoms in a paraffin chain along with a number of diethers were assessed in ethanol at 48 and 60 °C. The molecular weights at infinite dilution indicated that the compounds are unassociated. Solvation effects were observed for the monoethers having 14 or more carbon atoms in the hydrophobic portion of the molecule, but were absent for those molecules containing 12 carbon atoms or less. The apparent micellar weights suggested that association did not proceed beyond a dimer for most of the hexaoxyethyleneglycol compounds. The diethers obeyed Raoult's law up to the critical micelle concentration while different apparent association patterns were observed beyond this concentration.

Cryoscopic and Viscosity Studies of Polyisobutylene. Cryoscopic Deviation of Polyisobutylene Solutions from Raoult's Law

1943 ◽  
Vol 16 (1) ◽  
pp. 69-84
Author(s):  
A. R. Kemp ◽  
H. Peters
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Infinite Dilution ◽  
Freezing Point ◽  
Raoult’S Law ◽  
Ideal Solutions ◽  
Chain Lengths ◽  
Selection Of ◽  
Raoult's Law

Abstract 1. The cryoscopic method is not satisfactory for polyisobutylenes having chain lengths much over 40 isobutylene units, on account of the failure of their solutions to obey Raoult's law. 2. The present work has led to the selection of a Kcm value of 0.75×104 for n-hexane solutions of polyisobutylene for use in the equation M=(log ηr×Kcm)/C. 3. Extrapolation of cryoscopic data obtained on nonideal solutions to infinite dilution gives inordinately high molecular weight values compared with those based on freezing point measurements of ideal solutions. 4. Of several solvents studied, n-hexane was found to be the best for viscosity—molecular weight measurements of polyisobutylene. 5. Fractionation of polyisobutylene by diffusion into mixtures of n-hexane and acetone resulted in the separation of the lower polymer fractions.

Solution Properties and Phase Behavior of Ammonium Hexylene Octyl Succinate in Water and Water-Oil System

1970 ◽  
Vol 3 (1) ◽  
Author(s):  
Md. Hamidul Kabir ◽  
Ravshan Makhkamov ◽  
Shaila Kabir
Keyword(s):  
Critical Micelle Concentration ◽  
Phase Behavior ◽  
Liquid Crystalline ◽  
Carbon Number ◽  
Phase Region ◽  
Solution Properties ◽  
Middle Phase ◽  
Two Phase ◽  
Lamellar Liquid Crystal ◽  
Drug Ingredient

The solution properties and phase behavior of ammonium hexylene octyl succinate (HOS) was investigated in water and water-oil system. The critical micelle concentration (CMC) of HOS is lower than that of anionic surfactants having same carbon number in the lipophilic part. The phase diagrams of a water/ HOS system and water/ HOS/ C10EO8/ dodecane system were also constructed. Above critical micelle concentration, the surfactant forms a normal micellar solution (Wm) at a low surfactant concentration whereas a lamellar liquid crystalline phase (La) dominates over a wide region through the formation of a two-phase region (La+W) in the binary system. The lamellar phase is arranged in the form of a biocompatible vesicle which is very significant for the drug delivery system. The surfactant tends to be hydrophilic when it is mixed with C10EO8 and a middle-phase microemulsion (D) is appeared in the water-surfactant-dodecane system where both the water and oil soluble drug ingredient can be incorporated in the form of a dispersion. Hence, mixing can tune the hydrophile-lipophile properties of the surfactant. Key words: Ammonium hexylene octyl succinate, mixed surfactant, lamellar liquid crystal, middle-phase microemulsion. Dhaka Univ. J. Pharm. Sci. Vol.3(1-2) 2004 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

The entropy of liquid mixtures: I. The theory of Raoult's Law

1941 ◽  
Vol 60 (2) ◽  
pp. 76-84 ◽  
Author(s):  
A. J. Staverman ◽  
J. H. van Santen
Keyword(s):  
Liquid Mixtures ◽  
Raoult’S Law ◽  
Raoult's Law
Sign in / Sign up

Export Citation Format

Share Document