Novel “core-first” star-based quasi-model amphiphilic polymer networks

Abstract

Novel quasi-model networks based on “core-first” star (co)polymers have been synthesised. The polymeric networks (gels) were based on the hydrophilic, thermo- and pH-responsive 2-(dimethylamino)ethyl methacrylate (DMAEMA) and the non-ionic, hydrophobic methyl methacrylate (MMA). Specifically two homopolymer networks and three amphiphilic polymer networks were synthesised based on two block and one statistical “core-first” star copolymers. The precursors to and the extractables of the networks were characterised using Gel Permeation Chromatography and proton Nuclear Magnetic Resonance to determine the molecular weight, polydispersity and composition. The degrees of swelling (DSs) of the networks were then determined in both aqueous and organic solvents. The DSs in organic solvents and non-acidic water were dependant only on the composition of the conetworks while the DSs in acidic water were also affected by the architecture of the conetworks. Finally the networks were evaluated in terms of their ability to absorb and deliver hydrophilic and hydrophobic compounds that were used as “model drugs” and interestingly it was observed that the architecture of the networks, and not just the composition of the networks, affected the release of the compounds.