Stimuli-responsive materials based on helical polymers

Resumo

This thesis deals with the design, synthesis and evaluation as sensors of new stimuli-responsive materials based on helical polymers, more specifically, on chiral poly(pheylacetylene) copolymers. These studies have been developed in three chapters: Chapter 1 handles with tripodal supramolecular chemistry encompassing dynamic coordination chemistry and cation-pi interactions to control the elongation and spinning direction in dynamic helical polymers. This work describes the helical sense control in a poly(phenylacetylene) containing at least three different functional groups in the monomeric repetition unit, to which a metallic cation can be joined in different ways to form coordination complexes. Chapter 2 presents a new tool for creating multi-sensor materials via the control of the Chiral Conflict and Chiral Communication effects in dynamic helical polymers by using series of dynamic chiral copolymers that show both chiral conflict and chiral communication between comonomers. A variety of metal cations acting as external stimuli are selectively identified. Chapter 3 constitutes a further step in the development of multi-sensors from a new series of dynamic helical copolymers showing Chiral Conflict or Chiral Accord effects, to generate sensors capable of detecting different external stimuli from a single copolymer: solvent polarity, temperature and metal cations are those stimuli.