Composition for exploiting natural gas hydrates and application method thereof

A method for administering a composition for exploiting natural gas hydrates, wherein the composition comprises a reagent A and a reagent B;

• the method comprises the following steps:
• injecting the reagent A into a tube A;
• injecting the reagent B into a tube B;
• stretching the tube A and the tube B into a hydrate reservoir by using a reagent injection instrument;
• regulating a flow rate according to a proportion of each component;
• allowing the reagents to react at a preset reservoir position;
• and
• allowing water in the reservoir to participate in the reaction at the same time, wherein a reaction product is used for supporting the reservoir;
• wherein the reagent A is PEG400-polyurethane prepolymer;
• the reagent B comprises PEG400 and an initiator;
• a volume ratio of the PEG400-polyurethane prepolymer, the PEG400 and the initiator is (1-3000):(1-1000):(1-2000);
• a preparation method of the PEG400-polyurethane prepolymer comprises:
• mixing PEG400 and cyclohexanone which are separately dehydrated;
• stirring in an inert protective atmosphere under an acid condition;
• dropwise adding diphenyl methane diisocyanate;
• after the dropwise addition, increasing the temperature to 40° C.-70° C., and carrying out a reaction for 2-4 hours to obtain the PEG400-polyurethane prepolymer, wherein a mass ratio of PEG400, cyclohexanone and diphenyl methane diisocyanate is (1-880):(1-1300):(1-1600);
• the initiator comprises components by mass percentage:
• water:
• 50-55 wt %,
• triethanolamine:
• 5-10 wt %,
• triethylene diamine:
• 5-10 wt %,
• 1, 4-butanediol:
• 20-30 wt %, and
• methanol:
• 5-15 wt %.