The present invention relates to a method of preparing a polyrotaxane, said method comprising: performing a radical copolymerization of at least (a) a first polymerizable monomer having a stopper group, and of at least (b) a second polymerizable monomer, wherein said second monomer is complexed by a ring-shaped molecule; wherein during said copolymerization a copolymer threading said ring-shaped molecule is formed, wherein during said copolymerization said first monomer having a stopper group is incorporated into the chain of said copolymer at least partially between the ends thereof, and wherein said stopper groups prevent said ring-shaped molecule from disassembling from the copolymer; and wherein the amount of said first monomer having a stopper group is of from 0.1 mol % to 20 mol % based on 100 mol % of the total amount of polymerizable monomers. The present invention also relates to polyrotaxanes which can be prepared by using such a method. The present invention further relates to cross-linked polyrotaxanes, products which contain polyrotaxanes or cross-linked polyrotaxanes or which can be prepared from polyrotaxanes or cross- linked polyrotaxanes, and the use of polyrotaxanes or cross-linked polyrotaxanes.