摘要：

Novel poly(amidoamine)s (PAAs) containing disulfide linkages regularly arranged along the polymer chain, namely BPCY and BACCY, were synthesized by stepwise polyaddition of l-cystine to 1,4-bis(acryloyl)piperazine (BP) and 2,2-bis(acrylamido)acetic acid (BAC), respectively. Even if l-cystine contains four acid hydrogens, no evidence of cross-linking was found. All products were characterized by 1H and 13C NMR spectroscopy, and their average molecular weight determined by size exclusion chromatography. The polymerization rates were investigated by means of 1H NMR spectroscopy. In both cases, the experimental data were consistent with pseudo-second-order kinetics. The calculated kinetic constants were kc,BP = 8.10 × 10-3 min-1 L mol-1 and kc,BAC = 1.41 × 10-3 min-1 L mol-1 for the polyaddition of l-cystine to BP and BAC, respectively. A potentiometric study was carried out of BPCY and BACCY speciation as a function of pH, and the electrochemical activity of their disulfide bonds as a function of pH was ...

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