Polytetrafluoroethylene composite filter material and preparation method and uses thereof

A polytetrafluoroethylene composite filter material, comprising a support layer and a polytetrafluoroethylene microporous membrane layer, the support layer and the polytetrafluoroethylene microporous membrane layer are compounded by an adhesive, wherein the adhesive comprises a two-component polyurethane adhesive, a pore forming agent and an inorganic filler,

• wherein the pore forming agent is one or more selected from polyethylene oxide, polystyrene microspheres and polymethylmethacrylate;
• the mass fraction of the pore forming agent in the adhesive is 2% to 5%;
• and
• the inorganic filler is one or more selected from calcium carbonate, barium carbonate and magnesium carbonate;
• and the mass fraction of the inorganic filler in the adhesive is 3% to 8%,
• wherein the two-component polyurethane adhesive is prepared by reacting raw materials including polyester polyol and isocyanate polyester polyol;
• the mass ratio of the polyester polyol to the isocyanate polyester polyol is (0.8 to 1.4):1;
• the polyester polyol is prepared from raw materials including 20 to 30 parts by weight of adipic acid, 25 to 35 parts by weight of sebacic acid, 5 to 20 parts by weight of 1,2-propanediol, 15 to 30 parts by weight of butanediol and 25 to 40 parts by weight of diethylene glycol by esterification reaction at 140 to 160° C. for 2 to 4 h and polycondensation reaction at 200 to 220° C. for 1 to 3 h, and, the isocyanate polyester polyol is prepared by reacting raw materials including 10 to 15 parts by weight of polybutylene adipate, 20 to 35 parts by weight of polypropylene glycol and 15 to 25 parts by weight of phenylenedimethylene diisocyanate at 70 to 90° C. for 3 to 5 h.