ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A high-strength hydrogel with tunable gelation time for high-temperature and high-pressure plugging applications

Zixuan Zhou, Yong Fu, Fan Li, Jinhua Liu, and Daqi Li

Sinopec Research Institute of Petroleum Engineering Co., Ltd, Beijing, China

E-mail: lidq.sripe@sinopec.com

Received: 17 January 2026  Accepted: 22 March 2026

Abstract:

Hydrogel-based materials have emerged as promising candidates for lost circulation control based on their excellent injectability and sealing performances, however, they face problems such as difficult-to-control gelation times and low compressive strength after curing under high-temperature and high-pressure (HTHP) conditions. Herein, we constructed a novel curable hydrogel composed of acrylamide (AM), sodium p-styrenesulfonate (SSS) and sodium lignosulfonate (LS), denoted as P(AM-co-SS)/LS hydrogel for HTHP plugging applications. This hydrogel was synthesized via a one-pot thermal polymerization strategy under harsh conditions (150 °C/20 MPa), forming a dense three-dimensional crosslinked network, in which the mechanical performance and gelation behavior were effectively regulated by tailoring the polymer composition and the initiator–inhibitor balance. Experimental results demonstrated that the P(AM-co-SS)/LS hydrogel exhibited remarkable thermal stability, great mechanical strength (compressive strength up to 6.88 MPa and compressive strain exceeding 90%), and tunable gelation time ranging from 52 min to 3 h 12 min. Moreover, in wedge-shaped fractures with a width of 5 mm, the breakthrough pressure of P(AM-co-SS)/LS hydrogel reached 3.5 MPa, which manifests effective plugging in the fracture. This work offers a robust gel design strategy for HTHP lost circulation control and holds significant promise for complex subsurface sealing applications.

Keywords: Hydrogel plugging materials; High-temperature and high-pressure; Compressive strength; Pressure-bearing strength; Gelation time

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-04835-0

Chemical Papers 80 (7) 7539–7549 (2026)