Synthesis and Solution Self-Assembly of Poly(1,3-dioxolane)

Poly(1,3-dioxolane) (PDO) is widely used as a pH- and temperature-sensitive water-soluble polymer applied in functional hydrogels and nanoparticles. In this contribution, we report a series of highly efficient rare-earth triflate catalysts for a Brønsted-acid-free ring-opening polymerization of DO. The repeat unit of PDO comprises perfectly alternating hydrophilic ethylene glycol and hydrophobic methyl aldehyde units leading to hydrogen-bonding-controlled self-assembly in aqueous solution. Spherical aggregates are observed in transmission electron microscopy images whose sizes can be tuned by concentration and temperature, further confirming that the hydrate is derived from "blocked" water molecules through hydrogen bonding. The size and morphology of the aggregates can be modulated not only by the annealing process owing to the realignment of semicrystalline regions but also by metal salts generating rodlike, wormlike, or spherical structures. In this case, PDO is able to act as both a surfactant and as a reductant on account of the acidolysis of acetal moieties, which form a core–shell Cu-decorated hybrid material in situ in one step, thus providing a promising future template for the generation of metal nanoparticles.