Karst channel type water inrush efficient-blocking ultra-high expansion grouting material and preparation and using methods and application thereof

A preparation method of a karst channel type water inrush efficient-blocking ultra-high expansion grouting material, the method comprising:

• (1) adding a cross-linking agent into an acrylic acid solution, and then adding an active substance containing a hydrophilic group for polymerization reaction to obtain a precursor;
• (2) adding an initiator into the precursor obtained in step (1), heating for reaction to obtain a polymer solution, and smashing and drying the polymer solution to obtain primary water-absorbent resin particles;
• and
• (3) with the primary water-absorbent polymer resin particles as an inner core, uniformly spraying a gelling agent onto the primary water-absorbent resin particles, wherein part of the gelling agent penetrates into the inner core of primary water-absorbent polymer resin particles, followed by drying, to thereby form a shell structure comprised of the gelling agent attached to a surface of the primary water-absorbent polymer resin particles and creating polymer particles A of an inlaid type core-shell structure;
• and
• (4) providing a cross-linking solidifying fluid B with the polymer particles A;
• wherein
• the gelling agent is used to catalyze the cross-linking solidifying fluid B, the cross-linking forming a gel;
• the gelling agent is a composition of polyethylene glycol, 4,4′-methylene bis(o-chloroaniline) and polyether polyol;
• and
• the cross-linking solidifying fluid B is a substance capable of reacting with water.