Combining modular ligation and supramolecular self-assembly for the construction of star-shaped macromolecules
Résumé
A well-defined random copolymer of styrene (S) and chloromethylstyrene (CMS) featuring lateral chlorine moieties with an alkyne terminal group is prepared (P(S-co-CMS), M̄ n = 5500 Da, PDI = 1.13). The chloromethyl groups are converted into Hamilton wedge (HW) entities (P(S-co-HWS), M̄ n = 6200 Da, PDI = 1.13). The P(S-co-HWS) polymer is subsequently ligated with tetrakis(4-azidophenyl)methane to give HW-functional star-shaped macromolecules (P(S-co-HWS)) 4, M̄ n = 25 100 Da, PDI = 1.08). Supramolecular star-shaped copolymers are then prepared via self-assembly between the HW-functionalized four-arm star-shaped macromolecules (P(S-co-HW)) 4 and cyanuric acid (CA) end-functionalized PS (PS-CA, M̄ n = 3700 Da, PDI = 1.04), CA end-functionalized poly(methyl methacrylate) (PMMA-CA, M̄ n = 8500 Da, PDI = 1.13) and CA end-functionalized polyethylene glycol (PEG-CA, M̄ n = 1700 Da, PDI = 1.05). The self-assembly is monitored by 1H NMR spectroscopy and light scattering analyses. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.