Dynamic thickening investigation of the gelation process of PAM/PEI system at high temperature and high pressure

ABSTRACT

The gelation process of organically polymer gel was investigated by dynamic thickening measurements. Rheological measurements were used to evaluate the viscosity of the gel. During the gelation process, high temperature resulted in higher rate of crosslinking. Rigid and stable gel was formed in neutral and alkaline media, and the higher of the pH value, the faster of the gelation process. However, gel could not be formed in acid condition. Moreover, the rate of crosslinking increased with the increase of concentration of polymer and crosslinker. The addition of NH₄Cl elongated the gelation time significantly, but played a negative role in the gel strength, while a rigid gel was formed in the presence of Sodium acetate or trisodium citrate dehydrate. This paper summarizes the results and discusses how various parameters affect the gelation process of the gel.

GRAPHICAL ABSTRACT

KEYWORDS:

• Crosslinking rate
• dynamic thickening
• gelation process
• hydrolysis
• imidization

Acknowledgments

The authors thank all the financial support. This work was supported by PetroChina Innovation Foundation (NO. 2014D-5006-0309) and the National Natural Science Foundation of China (NSFC NO. 51404039 and 61572084). Valuable comments and suggestions from the reviewer are also gratefully acknowledged.