| abstract |
The invention relates to a waterproof air and moisture permeable microporous film, a three-layer composite material and a preparation method and application thereof. In the invention, the blend of polypropylene, linear low-density polyethylene and ethylene-octene copolymer is taken as the polymer matrix, and then the polymer matrix is added with inorganic filler and processing aid to be prepared into the microporous film with waterproof and air and moisture permeable functions through melt extrusion, flow casting and stretching. The microporous film is an intermediate layer and is manufacturedinto a three-layer composite material with an inner layer polypropylene nonwoven fabric and an outer layer polypropylene nonwoven fabric by direct hot pressing and compounding by utilizing the difference of the melting points among the linear low-density polyethylene in the polymer matrix of the microporous film, the ethylene-octene copolymer and the polypropylene. The composite material also canbe used as a waterproof and air and moisture permeable cushion layer for a slope type roofing and also can be taken as a waterproof and moisture-permeable liner layer at the inner side of a dry-hanging type decorative material for an external wall of a building. |