bioresorbable thermoset elastomers and methods of making the same are disclosed . in certain embodiments , the thermoset elastomers include soft segments comprising branched polyesters , and hard segments including urethane and / or urea . the thermoset elastomers are made in certain embodiments by curing a branched prepolymer with a cross - linking agent . in certain embodiments , the mechanical properties of the thermoset elastomers are tailored by selecting the average molecular weight of the prepolymer , or by tuning the ratio of prepolymer to the cross - linking agent during curing , or by selecting a cross - linking agent with specific chemical characteristics .