Stimuli-responsive hyperbranched poly(amidoamine)s integrated with thermal and pH sensitivity, reducible degradability and intrinsic photoluminescence

摘要: A series of hyperbranched poly(amidoamine)s (HPAs) were synthesized from the Michael addition copolymerization tris(2-aminoethyl) amine (TAEA) and two bisacrylamide monomers N,N′-cystamine (CBA) N,N′-hexamethylene (HMBA) at room temperature. The further modification with isobutyric anhydride led to isobutyramide terminated HPA (HPA-C4). 1H NMR 15N characterizations proved successful preparation these polymers. Moreover, beside contents TAEA, CBA HMBA units in composition, spectrometry could supply more structural information than spectrometry, such as ratio different groups polymers, transformation efficiency reactive primary secondary amines into C4 groups. GPC measurements not only gave molecular weight polydispersity, but also that all HPA-C4s containing disulfide bonds be degraded after being treated dithiothreitol (DTT). Turbidimetry showed had thermoresponsive property water. cloud point temperature (Tcp) was pH-dependent. DTT affect due induced polymer degradation. Although no traditional fluorophores existed HPA-C4s, emit blue fluorescence centered ca. 455 nm. intensity influenced pronouncedly by concentration, pH, oxidizing time.