High-porosity and high-modulus polishing layer, preparation method thereof, polishing pad and application of polishing pad

The invention discloses a high-porosity and high-modulus polishing layer, a preparation method of the high-porosity and high-modulus polishing layer, a polishing pad and application of the polishing pad. The high-porosity and high-modulus polishing layer is a thermosetting polyurethane polishing layer and has a rich pore structure, the pore structure comprises large pores and small pores and shows the characteristics of high energy storage modulus and low density, the energy storage modulus at the temperature of 25 DEG C is 50-250 MPa, the hardness and modulus of the high-porosity polishing pad can be improved, and the service life of the polishing pad is prolonged. The problems that the high-porosity polishing pad is poor in wear resistance, low in removal rate and poor in flatness are effectively solved. According to the preparation method, the preparation process of wet phase separation and then cross-linking curing is adopted, the thermosetting polyurethane polishing layer is formed, and unification of hi