In the last decade stimuli-responsive block copolymers (BCPs) have proven their utility for a range of important applications. These polymers are capable of changing their conformation, solubility, or even of breaking or forming covalent bonds upon, for instance, a change of temperature or pH value, light irradiation, electrochemical stimuli or the presence of an electrical or magnetic field. The presentation will focus on materials, which contain at least one selectively addressable segment, either chemically or physically. Porous nano structures based on functional BCPs as well as recent advances in inverse opal films prepared by using the so-called melt-shear organization technique will be highlighted and discussed in more detail. As another highlight, ultra-high molecular weight (UHMW) BCPs were prepared via an innovative synthetic concept using anionic copolymerization and it will also be demonstrated that despite the one-step approach, strongly segregated materials with highly ordered lamellae on the order of 100-200 nm were obtained. Optical properties, i.e., intense structural colors resulting from Bragg scattering at these thick lamella (or spherical domains) will be demonstrated for these self-assembled BCPs. In the case of soft colloidal crystal and inverted structures, which are also referred to as polymeric opals, applied external triggers lead to a remarkably fast and reversible change of their intriguing optical properties. A great benefit of opal structures by the melt-shear organization is their inexpensive and convenient preparation giving a good optical performance with iridescent reflection colours caused by Bragg diffraction. The talk will give some recent examples for the rational design of functional pure organic as well as hybrid porous materials with hierarchical architectures. Some of the presented polymer or polymer-templated structures can be advantageously used for direct conversion into ordered ceramic or carbonaceous materials. Herein presented functional materials are interesting candidates for a manifold of applications in the field of optical sensing and robust membrane technologies.

Self-assembly of stimuli-responsive polymers for optical sensing materials and smart porous membranes

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.