We present the synthesis of optically active polymers derived from S-phenylethyl acrylate and R-phenylethyl acrylate for the first time. Cu(0) wire-catalyzed single electron transfer-living radical polymerization (SET-LRP) methodology which provides a feasible platform makes its new application in designing and developing these two polymers. At various degrees of polymerizations (DPs) ranging from 100 to 400, first-order kinetics is observed. In all cases, SET-LRP demonstrates a rapid polymerization rate while maintaining excellent control over polymer's molecular weight, polydispersity and chain-end functionality. These advantages facilitate the development of both homopolymers and block copolymers through in situ chain extensions. The circular dichroism measurement confirms that the SET-LRP method yields optically active polymers derived from two enantiomeric monomers, which exhibit mirrored spectra. Graphical
Optically active polyurethanes (LPU and DPU) and racemic polyurethane (RPU) were synthesized by the self-polyaddition of the isocyanate-phenols which derived from the chiral and racemic tyrosine. All of the polymers were characterized by FT-IR, 1 H NMR, GPC , UV–Vis spectroscopy, circular dichroism (CD) spectroscopy, TGA and X-ray diffraction (XRD), and the infrared emissivity values were investigated in addition. LPU and DPU were two enantimorphs, they possessed helical configurations and higher degree of hydrogen bondings compared to the RPU which presented random coiled molecular chain . The crystallinity and thermal decomposition temperature of LPU and DPU were higher than that of the RPU due to the more regular secondary structure which facilitate the formation of a large number of inter-chain hydrogen bonds . Consequently, the LPU and DPU exhibited lower infrared emissivity values (8–14 μm), which came down to 0.611 and 0.625.
危险品化学品经营许可证（带存储）