One-dimensional optical reflectors based on self-organization of polymeric comb-shaped supramolecules

Abstract

One-dimensional optical reflectors based on self-organization of polymeric comb-shaped supramolecules Kosonen, H; Valkama, S; Ruokolainen, J; Torkkeli, M; Serimaa, R; ten Brinke, G; Ikkala, O Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Abstract. We demonstrate that complexation of dodecylbenzenesulphonic acid, DBSA, to a diblock copolymer of polystyrene-block-poly(4-vinylpyridine), PS-block-P4VP, leads to polymeric supramolecules PS-block-P4VP(DBSA)y (y = 1.0, 1.5, and 2.0), which self-organize with a particularly large lamellar periodicity in excess of 1000Å. The structures consist of alternating PS and P4VP(DBSA)y layers, where the latter contains smaller internal structure, probably lamellar. The DBSA side chains are bonded to the pyridines by protonation and hydrogen bonding and they effectively plasticize the material. In this way relatively well-developed structures are obtained even without annealing or macroscopic alignment. Transmission and reflectance measurements show that a relatively narrow and incomplete bandgap exists for supramolecules of high molecular weight block copolymer at ca. 460 nm.

Self-assembled polymeric solid films with temperature-induced large and reversible photonic-bandgap switching

“…Many methods have been demonstrated to form photonic bandgaps, such as lithographic and etching techniques 10 , spontaneous self-assembly of colloids 11 , synthetic opals [12][13][14] , inverted opals 15,16 and block copolymers [17][18][19][20][21] , each having their own characteristic advantages and drawbacks. The aim of this work is to demonstrate responsive photonic bandgaps in the solid state based on self-assembly of block copolymers, where temperature changes cause pronounced and reversible switching, which manifests itself, for example, as distinct colour changes.…”

“…Previously we have shown that comb-shaped polymeric supramolecules can be used to prepare one-dimensional optical refl ectors in a facile way 20 . Such systems did not show optically responsive or switching behaviour, but it can be expected that phase transitions of self-assembled block copolymers could lead to a useful platform for switchable bandgaps in the solid state.…”

“…Previously, it was observed that the comb-shaped architecture, formed by bonding dodecylbenzenesulphonic acid (DBSA) to the P4VP-block of PS-block-P4VP (where PS is polystyrene) caused large stretching of the chains thus leading to a visible bandgap 20 . In the present work, the additional temperature responsivity is based on the hypothesis that the alkyl combs should not be bonded by strong ionic interaction, but rather by weaker hydrogen bonding, still keeping the protonation of P4VP.…”

Transport and Electro‐Optical Properties in Polymeric Self‐Assembled Systems

“…3.10). More generally, related hierarchically self-assembled systems allow tuning of the properties by controlling the structures at different length scales [44,87,207,[217][218][219][220][221][222]. Polyelectrolyte-surfactant complexes self-assemble into various nanoscale structures and they can exhibit electrical conductivity [223,224].…”

“…For certain large area applications, simpler techniques could be more suitable. Spontaneous self-assembly of colloids [375], synthetic opals [379][380][381][382][383][384], inverted opals [379,[385][386][387] and block copolymers [218,219,221,378,[388][389][390][391][392][393][394][395][396][397][398][399][400][401][402], on the other hand, allows the preparation of small enough structures. Although self-assembly leads to a well-defined local order and offers a potentially low-cost method for the production of photonic crystals, it is nontrivial to achieve perfectly ordered structures over the macroscopic length scale combining carefully engineered defects.…”