Abstract
Phase separation and gelation of the aqueous solutions of acrylamide-acrylic acid copolymers in the presence of aluminium chloride are studied as a function of pH and ionic strength. At pH 7, only phase separation is observed as a flocculation of aluminium hydroxide particles by polymer bridges, but because of their small positive residual charge the phenomenon is partially due to electrostatic interactions and consequently depends on the ionic strength of the solution. At pH 5, gelation attributed to the presence of polycations Al 3+ 13 occurs for values of the polymer charge which increase with increasing ionic strength. A qualitative model is proposed to define the conditions and the limits of gelation in such systems.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
