Glycomonomers of sialic acid in which the acetamide group at C-5 was converted into two kinds of CC doublebond substituents were prepared and the fully protected glycomonomers were directly polymerized before deprotection steps. Radical polymerization with acrylamide in DMF in the presence of ammonium persulfate and N,N,N’,N’-tetramethylethylenediamine proceeded smoothly and gave corresponding sialopolymers