Environmental-Friendly, Long-Lastingly Moist Phase Change Gel with Tunable Cross-Linking Time for Effective Borehole Sealing.

Flexible environmental phase change gel (EPCG) is a promising and attractive material for borehole sealing due to its relatively lower usage, tunable cross-linking time, and potential degradable properties. However, conventional borehole sealing materials lack a lower manufacturing cost, lower reaction temperature, remarkable antimold function, and admirable hole sealing performance for long-term high-performance borehole sealing. Hence, it remains a critical challenge to realize a flexible phase-change gel featuring tunable cross-linking time, antimold ability and degradability, and long-lasting moist performance for high-performance borehole sealing. Herein, we illustrate a facile approach to fabricate the borehole sealing materials based on environmentally friendly, antimold, long-lasting moist composite phase-change gel fabricated from a modified cellulose gel polymer network. The prepared phase change gel presents adjustable cross-linking time with the initial setting time of 30-60 min, which could be used to seal holes with different drilling parameters. Furthermore, the fabricated gel illustrates reliable water retentiveness performance and antimold ability, assuring the long-period borehole sealing effect. Furthermore, EPCG has been applied for borehole sealing and shows great sealing ability and gas extraction performance. Therefore, this work paves the way to fabricate a flexible phase-change gel featuring tunable cross-linking time, antimold ability, and long-lasting moist performance for high performance borehole sealing.