Patent ID: 8048967

Claim:
A method for preparing nylon microspheres, wherein the method includes steps (1), (2) and (3) or steps (1′), (2) and (3) as follows: (1) dispersing a radically polymerizable monomer in a molten lactam monomer, and adding a free radical initiator, so that radical polymerization of the radically polymerizable monomer is carried out, to give a mixture of a free radical polymer and the lactam monomer; or (1′) providing a mixture of a free radical polymer and a molten lactam monomer; and (2) adding an initiator and an activator, used for anionic ring-opening polymerization of the lactam monomer, to the mixture obtained in step (1) wherein the remaining radically polymerizable monomer and water are removed, or to the mixture obtained in step (1′), so that the anionic ring-opening polymerization of the lactam is carried out to give a polymer alloy of the free radical polymer/polyamide; and (3) removing the free radical polymer in the polymer alloy obtained in step (2) by dissolution, giving nylon microspheres.