Dilute solutions of polyelectrolytes—VII. Viscometric study of copolymer of N,N-dimethyl-N,N-diallyl ammonium chloride with acrylamide in aqueous solutions

1986 ◽  
Vol 22 (8) ◽  
pp. 683-686 ◽  
Author(s):  
A. Flondor ◽  
S. Maxim ◽  
S. Ioan
1946 ◽  
Vol 24a (1) ◽  
pp. 8-14 ◽  
Author(s):  
D. G. Douglas ◽  
C. A. MacKay

Surface tension measurements have been made on normal heptylic, pelargonic, capric, and lauric acids above their melting points and on aqueous solutions of heptylic, pelargonic, capric, and undecylic acids, at various concentrations. A modified capillary rise method was employed. The results indicate that the surface does not reach the stable state at once but requires considerable time, being slower for more dilute solutions and longer chain molecules. Evidence is given for the existence of a monolayer of closely packed molecules, with long axes perpendicular to the surface, each molecule occupying an area of approximately 25 Å for heptylic acid.


1906 ◽  
Vol 45 (1) ◽  
pp. 241-259 ◽  
Author(s):  
John Gibson

Although great advances have been made during the last thirty years in our knowledge of dilute solutions, there has been no corresponding advance in respect of concentrated solutions. This is primarily due to the fact that hitherto no simple and general relationship has been discovered between the conductivity and the concentration of concentrated solutions of electrolytes. Ostwald's law of dilution holds only for dilute solutions of weak electrolytes, and the formulæ of Rudolphi and Van T'Hoff are applicable only to dilute solutions of good electrolytes. It seems therefore important to inquire whether the difficulty may not be to some extent overcome by an alteration in the mode of representing the facts.


2018 ◽  
Vol 2 (3) ◽  
pp. 34 ◽  
Author(s):  
Katarzyna Szymczyk ◽  
Magdalena Szaniawska ◽  
Anna Taraba

Density, viscosity and speed of sound of aqueous solutions of nonionic surfactants such as polyoxyethylene (20) sorbitan monolaurate (Tween 20) and polyoxyethylene (20) sorbitan monostearate (Tween 60) at T = 293, 303 and 313 K are reported. From these measured values different parameters such as, for example, isentropic compressibility, molecular free length, acoustic impedance, primary hydration numbers and internal pressure have been calculated and employed to discuss molecular packing, structural alteration and molecular interactions. The variation in these parameters with temperature indicates that the mobility of surfactant molecules increases the disordered state of the liquid (surfactant + water) due to irregular packing of the molecules. Also, for Tween 20 solutions, more conversion to bulk water of the structured water molecules was observed, obtaining lower compressibilities and higher values of hydration numbers as well as internal pressure for a given T.


Sign in / Sign up

Export Citation Format

Share Document