NOVELTY - A flexible high thermal insulating polymer composite material is polymer blend comprising crosslinked ethylene-vinyl acetate (EVA), EVA, peroxide vulcanizing agent, thermoconductive filler and ionic liquid (III) in mass ratio of 100-100.5:100:0-0.5:100-1403.5:0.5-100.25. Crosslinked ethylene-vinyl acetate is irregular copolymer (I) or (II). Ethylene vinyl acetate contains vinyl acetate content of 5-40 %mass. Thermoconductive filler is spherical alumina powder, magnesium oxide powder, silicon nitride powder and/or carbon silicon powder, and has particle diameter of 10 nm to 100 mm.    USE - Flexible high thermal insulating polymer composite material is used for manufacturing solar silicon battery and light emitting diode lamp.    ADVANTAGE - The flexible high thermal insulating polymer composite material has excellent thermal conductivity and insulation property, and can be manufactured efficiently and economically by simple method without affecting the environment.    DETAILED DESCRIPTION - A flexible high thermal insulating polymer composite material is a polymer blend comprising crosslinked ethylene-vinyl acetate (EVA), EVA, peroxide vulcanizing agent, thermoconductive filler and ionic liquid of formula: A+B'- (III) in the mass ratio of 100-100.5:100:0-0.5:100-1403.5:0.5-100.25. The crosslinked ethylene-vinyl acetate is irregular copolymer of formula (I) or (II). The ethylene vinyl acetate contains vinyl acetate content of 5-40 %mass. The thermoconductive filler is spherical alumina powder, magnesium oxide powder, silicon nitride powder and/or carbon silicon powder, and has particle diameter of 10 nm to 100 mm.    m,n,p,q=10-5000;    R=S, silanyl or epoxy group-containing phenol oligomer group;    A=imidazole-type group of formula (i) or pyridine-type group of formula (ii);    R5=1-16C alkyl;    B'=F-, Br-, Cl-, I-, tetrafluoroborate or hexafluorophosphate;    R6,R7=1-16C alkyl;and    R3,R4=not defined.    N.B. R3 and R4 are not defined, and R6 and R7 are defined, but does not appear in any other structure or group. An INDEPENDENT CLAIM is included for preparation of flexible high thermal insulating polymer composite material. Crosslinked EVA, EVA and vulcanizing agent are mixed in the mass ratio of 1000:1000:0.1:5, at 30-200 degrees C and dynamic vulcanization is carried out at 7 degrees C, and dried to obtain base material. The content of vinyl acetate in crosslinked ethylene vinyl acetate is 50-80%. The content of vinyl acetate in ethylene vinyl acetate is 5-40%. The vulcanizing agent is sulfur, peroxide vulcanizing agent, silane containing hydrogen, and/or resin-based vulcanizing agent. When the vulcanizing agent is peroxide vulcanizing agent, it provides free radicals to form mesh structure between ethylene vinyl acetate and crosslinked ethylene vinyl acetate. When the vulcanizing agent is sulfur, silane containing hydrogen, or resin-based vulcanizing agent, a grafting reaction occurs between ethylene vinyl acetate and crosslinked ethylene vinyl acetate. The obtained base material is added with thermoconductive filler, ionic liquid, and melt blending is carried out at 160 degrees C for 7-8 minutes to obtain high thermal insulation flexible polymer composite. The mass ratio of thermally conductive filler and base material is 0.5-7:1.