Rh(I) Catalyzed Polymerization of Propargylated Monosaccharides to Electrospinable Helically Chiral Linear Polyacetylenes and Sorption-Active Porous Polyacetylene Networks

Abstract

We report the Rh(I)-catalyzed chain-growth polymerizations of propargylated monosaccharides to form π-conjugated polyacetylene-type products with the monosaccharide substituents attached to the polyacetylene backbone via short methylene spacers. The homopolymerization provides helically chiral linear polyacetylenes of M _w  ~ 20,000 soluble in either water (monosaccharide substituents with free OH groups) or organic solvents (acetylated monosaccharide substituents). The methodology is established for the transformation of prepared chiral polymers into fibers (average diameter ~2.7 μm) taking advantage of the electrospinning technique. Copolymerization of propargylated monosaccharides with 1,3,5-triethynylbenzene cross-linker provides hyper-cross-linked polyacetylene networks with monosaccharide units content up to 46 wt.%, permanent micro/mesoporosity and S _BET area up to 482 m² g⁻¹. The monosaccharide substituents of the networks serve as centers active in reversible isothermal adsorption of water vapor from the air. The achieved H₂O capture capacity of 200 mg g⁻¹ (298 K, RH = 90%) shows monosaccharides as promising (co)building blocks for the construction of porous materials effective in water harvesting from air.