Open-pore polyurethane rigid foam prepared from polyurethane rigid foam degradation liquid

The invention relates to an open-pore polyurethane rigid foam prepared from a polyurethane rigid foam degradation liquid. The open-pore polyurethane rigid foam is prepared by reacting the polyurethane rigid foam degradation liquid, a polyhydric alcohol formula composition, a foaming agent and polyisocyanate, wherein the polyurethane rigid foam degradation liquid accounts for 0.1%-15% of the total weight of a material, the polyhydric alcohol formula composition accounts for 20%-52% of the total weight of the material, the foaming agent accounts for 0.3%-15% of the total weight of the material, and an isocyanate index is 70-140. According to the open-pore polyurethane rigid foam, the waste polyurethane rigid foam degradation liquid is firstly used for synthesizing the open-pore polyurethane foam with high aperture ratio and lower density, one the one hand, the problem of environmental pollution brought by a waste polyurethane rigid foam is solved, and on the other hand, the cost of raw materials is reduced, and considerable economic benefit is achieved. The prepared open-pore polyurethane rigid foam achieves the aperture ratio more than 70% and is low in density, thereby being a very good sound absorbing material used in building. The prepared open-pore polyurethane rigid foam is capable of providing an effective technical support for recycling the waste polyurethane rigid foam.