Self-assembly of poly(2-alkyl-2-oxazoline-)-g-poly(d,l-lactide) copolymers
Résumé
In this article, is reported for the first time the preparation of nanoparticles from graft copolymer composed of a hydrophilic backbone made of poly(2-methyl-2-oxazoline-co-2-pentyl-2-oxazoline) and hydrophobic poly(d,l-lactide) grafts. The copolymers were synthesized by the grafting-onto approach through the Huisgen 1,3-dipolar cycloaddition reaction. The success of the reaction was confirmed by H-1 NMR, FTIR and thermogravimetric analysis (TGA). Different copolymers were prepared from two molecular weight backbones (5.7 x 10(3) and 14.2 x 10(3) g mo1(-1)) giving graft copolymers with molecular weight in the range of 3.7 x 10(4) to 113 x 10(4) g mo1(-1). These copolymers self-assembled to form nanoparticles in water. Nanoparticles of spherical shape and various morphologies, going from polymersomes to core-shell and homogenous spherical nano-objects, were imaged by cryo-transmission electron microscopy (cryo-TEM) and analyzed by dynamic light scattering (DLS) and small -angle neutron scattering (SANS)