Composition for polyurethane foaming, polyurethane foam and use thereof

A composition for polyurethane foaming, a polyurethane foam and a use thereof. The composition contains two different polyols with a polyethylene oxide ether structure and a polypropylene oxide ether structure, and a specific type of catalyst, flame retardant and water are added thereto; at the same time, the composition contains a small amount of a surfactant and other small molecular alcohols. The traits of the product are that it is pale yellow and transparent, and the product is not layered during long-term storage. The above-mentioned composition and polyphenylpolymethylene polyisocyanate (PAPI) produce a low-density polyurethane foam by means of a foaming machine. The foam has a good thermal insulation effect and a high rate of yield, and the foam has a flame retardant property, that is to say, same can be used for construction insulation, and can also be used for packaging a buffer material, has a good thermal insulation, adhesion and dimensional stability, and has a low odor during the process of construction, the foaming agents all use water, and do not contain chlorofluorocarbon substances that destroy the ozone layer and climate.