Synthesis and Characterization of Novel Amphiphilic Azo-Polymers Bearing Well-Defined Oligo(Ethylene Glycol) Spacers

Four novel azo-polymers bearing oligo(ethylene glycol) spacers were synthesized and characterized. Monomers were prepared by esterification of the RED-PEG dyes previously synthesized by us: N-methyl-N-{4-[(E)-(4-nitrophenyl)diazenyl]phenyl}-N-(5-hydroxy-3-oxapentas-1-yl)amine (RED-PEG-2), N-methyl-N-{4-[(E)-(4-nitrophenyl) diazenyl] phenyl}-N-(8-hydroxy-3,6-dioxaoctas-1-yl)amine (RED-PEG-3), N-methyl-N-{4-[(E)-(4-nitrophenyl) diazenyl] phenyl}-N-(11-hydroxy-3,6,9-trioxaundecas-1-yl)amine (RED-PEG-4) and N-methyl-N-{4-[(E)-(4-nitrophenyl) diazenyl] phenyl}-N-(17-hydroxy-3,6,9,12,15-pentaoxaheptadecas-1-yl)amine (RED-PEG-6) with methacryloyl chloride. The obtained monomers (nPEGMAN series) were polymerized in the presence of AIBN in THF to give the corresponding azo-polymers (pnPEGMAN series). Also, Langmuir films were prepared with these polymers; the obtained monolayers exhibited good reversible behavior upon successive compression/expansion cycles. (C) Koninklijke Brill NV, Leiden, 2012