Amphiphilic helical polyacetylenes

Synthesis and Tunable Chiroptical Properties of Amphiphilic Helical Polyacetylenes... 

Tang and co-workers used leucine-functionalized phenyl acetylene derivatives for the construction of amphiphilic helical polymers, which were envisioned to be both semi-conducting and biocompatible, leading to diverse applications such as biosensors [36]. The polymerization was performed with a rhodium catalyst and resulted in high molecular weight polymers, particularly for polyacetylene la (1.5 10 g/mol). Interestingly, only the polymers in which the stereo-center was closely located to the helical backbone (la and lb) showed a CD signal and were optically active (Fig. 6). 

Thermosensitive, and amphiphilic polymer bmshes optically active polymers consist of helical poly(iV-propargylamide) main chains and thermosensitive poly(iV-iso-propylacrylamide) (PNlPAm) side chains, were prepared via a novel methodology combining catalytic polymerization, atom transfer radical polymerization (ATRP), and click chemistry. The characterization of GPC, FT-IR, and H-NMR measurements indicated the successful synthesis of the novel amphiphilic polymer brashes. For the confirmation of helical structure of the polymers backbones and the optical activity of the final brashes used UV-Vis and CD spectra. The polymer with optically active cores (helical polyacetylenes) and thermosensitive shells (PNlPAm) brashes self-assembled in aqueous solution forming core/shell structured nanoparticles [137]. 

L. Ding, C. Chen, J. Deng, W. Yang, Optically active thermosensitive amphiphilic polymer bmshes based on helical polyacetylene preparation through click onto grafting method and self-assembly. Polym. Bull. 69, 1023-1040 (2012)... 

A group of new amphiphilic macromolecules comprised of hydrophobic polyacetylene backbone and hydrophilic pendant groups of naturally occurring species such as amino acids, saccharides, and nucleosides are synthesized. The polymers exhibit solvatochromism. The macromolecular chains show helical confommtions that depend on the molecular structures of the pendants, solvent, temperature, pH, and additives. 

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