Fabrication of Dendrimer-like PAMAM Based on Silica Nanoparticles^†

A G 4.0 dendrimer-like poly(amido amine) (PAMAM) based on silica nanoparticles was fabricated via a divergent approach. It was built from γ-aminopropyl silica nanoparticles (APSN) core via repetitive addition of acrylate (MA) and hexylenediamine (HDA). FT-IR and EA were used to monitor the progress of dendrimer during each step. The amino group content of the resulting product increased from 0.49 to 3.72 mmol/g after the 4th generation. In addition, the percentage of grafting increased with increasing generation and reached to 65.9% after 4th generation. It was found that the resulting silica nanoparticles could be dispersed in methanol with a mean hydrodynamic particle diameter of 152.7 nm although the silica nanoparticles had agglomerated during the storage period.