A graphene-enhanced high-barrier and fast-curing film for deep in situ condition preserved coring in coal seams

Abstract

Scientific research on deep in situ resources is highly important to the theory and technology system construction for deep in-situ resource exploitation. To obtain high-condition preserved core samples, it is vital to maintain the original material, humidity and luminous flux information inside the core. Therefore, this study proposes a research and development strategy for a high-toughness and high-barrier sealing film based on the molecular structure design and filler synergistic enhancement via a deep solid-state sealing film using in situ substance preservation (ISP), in situ moisture preservation (IMP) and in situ light preservation (ILP) coring principles. A graphene/epoxy composite sealing film with a high barrier, high strength and high toughness was developed. The oxygen permeability of the film was 0.23 cm3/(m2·d), the water vapor permeability was 1.26 g/(m2·d), and the light transmittance was 0. The tensile strength reached 15.4 MPa, and the toughness was 5242.9 kJ/m3. The results from the film substance and moisture preservation performance verification experiments showed that the sealing film had an excellent sealing effect on small molecules, such as water, alkanes and even ions, which further verified that the sealing film greatly contributed to the maintenance and preservation of deep in-situ resource reserves and abundance.

Keywords

• ISP-IMP-ILP-coring
• Graphene/epoxy resin composites
• Sealing film