One catalyst-free method of forming a polyurethane comprises forming a first emulsion comprising a first monomer, a surfactant, a water immiscible organic solvent, and water. The first monomer comprises two or more pentafluorophenyl carbonate groups. The first emulsion is combined with an aqueous mixture containing a second monomer comprising two or more nucleophilic amine groups, thereby forming a second emulsion. The first and second monomers of the second emulsion are allowed to react by interfacial polymerization, thereby forming a polyurethane. The polyurethane can have a number average molecular weight (Mn) of about 30000 to about 80000. The method is compatible with introducing pendant functionality into the polyurethane by way of cyclic carbonate precursors to the first monomer.