Fabrication of Oxidative and pH Dual-Responsive Photonic Crystals Based on Sulfide-Containing Block Copolymers

Abstract

Photonic crystals (PCs) derived from responsive polymers exhibit adjustable photonic band gaps under external stimuli, and they have abundant applications in different fields. Herein, oxidative and pH dual-responsive copolymers were synthesized using reversible addition–fragmentation chain transfer (RAFT) polymerization with a functional monomer of combined phenyl vinyl sulfide (PVS) and N,N′-(dimethylamino) ethyl acrylate (DMAEA). The oxidatively responsive PVS segment generated copolymers with a refractive index (RI) change, and the pH-responsive DMAEA segment generated copolymers with a distance change in the aggregation state. Fabricating PCs with these copolymers resulted in unique dual-responsive behavior, e.g., the reflective peaks of PCs exhibited blue shifts to varying degrees under different oxidative and pH conditions. This report presents a high refractive index polymer derived from S-vinyl sulfide derivatives, in which the refractive index changed through selective oxidation and dual responsiveness was observed when the derivatives were combined with DMAEA units. Owing to changes in the RI and the period distance in PCs, a predictable change in the band gap of PCs for the aim of realizing a dual-responsive PC sensor was successfully obtained.

Fabrication of multi-responsive photonic crystals based on selenium-containing copolymers

“…SEM, water contact angle, reflectance spectroscopy and GPC (DMF) measurements were carried out using the instruments and test methods described in ref. 38. The molecular weight and molecular weight distribution of the polymer after oxidation were measured using a GPC (Waters 6250) (RI detector) equipped with a PL aquagel-OHMIXED-M column at 25 °C calibrated with PEG standards with a flow rate of 1.0 mL min −1 .…”

“…Such a PC showed multiresponsive behavior derived from oxidative changes in the ‘ n ’ value of PVS and from pH changes in the ‘ d ’ value of DMAEA. 38 The results indicated that the obtained PC showed multiresponsive behavior with both redox and pH stimulation. However, due to the contradiction between the DMAEA unit content and the overall refractive index of the polymer, only the block copolymer exhibited the dual response.…”

“…Fabrication of P(PVSe-co-4VP) SiO 2 IOPC P(PVSe-co-4VP) SiO 2 IOPC was prepared using the same procedure as in ref. 38.…”

One-pot thiol-free synthetic approach to sulfides, and sulfoxides selectively

“…Organosulfur compounds constitute a significant part of organic synthesis 1 because they are useful in medicinal chemistry, 2 materials science, 3 and natural product syntheses. 4 Thioethers (sulfides) have found attractive applications in the pharma industry.…”

Highly Ordered Porous Inorganic Structures via Block Copolymer Lithography: An Application of the Versatile and Selective Infiltration of the “Inverse” P2VP-b-PS System

“…By decreasing the BCP film thickness to scale consistently with the natural period of the polymer ( L 0 ), it is possible to generate a range of structures. These morphologies can be utilized in several industrial applications, such as lithographic masks, membranes, and photonics . Moreover, the BCP can act as an engineered template for inclusion of inorganic species. , The confinement of a polymer in a thin film (typically <100 nm) changes its behavior compared to the bulk counterpart: thin films are subjected to interactions with the interfaces, for example, substrate and air.…”