1 research outputs found
Confinement effects in the step-growth polymerization within AAO templates and modeling
Nanostructured polyurethanes have attracted substantial interest for the generation of ¿smart¿ surfaces,
but step-growth polymerization at the nanoscale has scarcely been reported. In this work, the synthesis
of polyurethanes by step-growth polymerization in the nanocavities of anodized aluminum oxide (AAO)
templates is studied, finding that the kinetics of the reaction was faster than in bulk, while the molecular
weight and the dispersity were reduced. A mathematical model was developed to explain these differences,
taking into account the chemical and physical interactions encountered in the reaction between
the monomers (diisocyanate and dialcohol) for nanoconfined in AAO and bulk. In nanoconfinement, the
polyaddition is catalyzed by hydroxyl groups on the pore wall, resulting in an increase in the rate of
polymerization during the early stages of the reaction. At high conversions, the limited diffusion of the
polymer chains results in a slower polymerization and a dispersity lower than that expected from bulk.Ministerio de Economía y Competitividad (MAT2014-53437-C2-
1P, MAT2017-83014-C2-2-P and CTQ2016-80886R) and IKERBASQUE
foundation, University of Basque Country (UFI/11/56), Basque
Government (GVIT 999-16, postdoctoral fellowship and Etortek
Nanoiker IE11-304) are gratefully acknowledged for their financial
supportPeer Reviewe