Abstract
AbstractThe shear rheology of diluted to concentrated suspensions of weakly cross‐linked sodium polyacrylate hydrogels were investigated by concentric cylinder rheometry. The size of the swollen gel particles is dependent on the initial size of the dry particle and on the nature of the added salt. Polyvalent salts are more efficient for contracting the swollen particles than monovalent ones. When suspended in water or in monovalent salt solutions, the viscosity at low concentrations shows a behaviour very similar to the one of flexible polymer solutions. Below the critical overlap concentration, the viscosity is independent of shear rate. The intrinsic viscosity is very large, on the order of 10–15 dL/g. This is in agreement with the large size of these swollen particles. Suspensions of such swollen gel particles are thus a good model for extremely high molecular weight polymer solutions. In polyvalent salt solutions different behaviour of the viscosity curves versus concentration was observed. This effect is caused by chemical cross‐linking of the hydrogel by polyvalent ions. © 1994 John Wiley & Sons, Inc.
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
