The polymer was synthesized by post-polymerization modification of copoly NAS positive 4%, similarly to what described in . In a two neck round bottom flask, copoly NAS positive 4% (0.5 g, 0.0483 mmol) was solubilized with 5 mL of anhydrous THF and degassed for 5 minutes by insufflating argon. 11-azido-3,6,9-trioxaundecan-1-amine (0.105 g, 0.483 mmol) was then added to the reaction mixture and the reaction proceeded at room temperature for 5 hours.