Synthesis and Characterization of Stearoyl Modified Poly (Glycerol Adipate) Containing ATRP Initiator on its Backbone

Poly (glycerol adipate) is enzymatically prepared by reacting glycerol with divinyl adipate in the presence of a lipase as catalyst fromCandida Antarcticatype B (CAL-B). The reaction yields linear polyesters with free pendent hydroxyl groups. Poly (glycerol adipate) is hydrophobically modified by incomplete acylation of some of the pendent hydroxyl groups using stearoyl chloride. The resulting polymer is further functionalized with α-bromoisobutyryl groups. The final polymer is purified and well characterized to calculate the ratio of substitution in both cases. Furthermore, nanoparticles in water are prepared from the functionalized polymer using the interfacial precipitation method. Dynamic light scattering measurements depict nanoparticles with relatively narrow size distributions and with an average hydrodynamic radius of 70 nm. Additionally, transmission electron microscopy images reveal well dispersed spherical nanoparticles with nanophase separation. Finally, the interactions between the graft copolymers and lipid monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) are investigated on a Langmuir trough equipped with a fluorescence microscope.