Low-temperature-resistant high-strength high-toughness modified fluororubber semi-interpenetrating network film material and preparation method thereof

The invention discloses a modified fluororubber semi-interpenetrating network film material and a preparation method thereof, and the modified fluororubber semi-interpenetrating network film material is prepared by the following steps: preparing a first component solution: adding solid fluororubber into a solvent, stirring at 60 DEG C for 2 hours, and cooling at room temperature; preparing a second component solution: adding a polyisocyanate curing agent into the hydroxyl-terminated liquid fluororubber, uniformly stirring, then adding a catalyst, and stirring for 10 minutes at normal temperature; preparing a third component solution, namely dissolving dihydric alcohol, fluorine-containing isocyanate and a fluorine-containing micromolecule chain extender in a solvent, uniformly stirring, then adding a catalyst, and stirring at normal temperature for 10 minutes; and preparing a film material: adding the first component solution, the second component solution and the third component solution into a container, st