Thin Film Structure of Block Copolymer–Surfactant Complexes: Strongly Ionic Bonding Polymer Systems

Abstract

We present a structural investigation of thin films of diblock copolymers PS−P4VP in which 4VP forms an ionic bond with a sterically demanding surfactant, bis (2-ethylhexyl) sulfosuccinate acid (AOT). The results depend strongly on the interplay between microphase separation and surfactant ordering. Protonation of the P4VP homopolymer or diblock PS-b-P4VP with AOT leads to a multilayer structure in which the surfactant determines the layer thickness. In thin films of the protonated block copolymer, the segregation between the blocks generates nanostructures with an inplane periodicity defined by the molecular masse of the copolymer and the stoichiometry of the complex. Variation of the composition of the blocks and the molar ratio AOT/pyridine leads to structural transitions: cylinders of (AOT/P4VP) → lamellae → cylinders of PS. Remarkably, regardless of the morphology, the bcp microdomain structure remains orthogonal to the air substrate interface. Finally, we show that hydrolysis of AOT results in the formation of pores with a variable geometry useful for templating two-dimensional inorganic structures.

Gelation Study on a Hydrophobically Associating Polymer/Polyethylenimine Gel System for Water Shut-off Treatment

“…11 Moreover, the metallic cross-linking reaction may result in the gel syneresis in the presence of multivalent cations because of the excessive cross-linking reaction. 12 Despite some disadvantages, the metallic cross-linker, such as chromium(III) acetate, is still commonly used with polymer for water shut-off because of its low cost and relatively well performance. 13 In contrast, the covalent bond generated by the organic cross-linker and polymer is relatively stable at high temperature and then contributes to stable gels.…”

A new route to prepare multiresponsive organogels from a block ionomer via charge-driven assembly

“…2(b)), which becomes less pronounced upon the addition of SO 3 H groups. Meanwhile, a peak at 1038 cm À1 , which can be assigned to symmetric stretching vibration of SO 3 H, 16 has been replaced by a peak at 1033 cm À1 . Therefore the existence of ionic bonding between pyridine groups on PS-b-P2VP and SO 3 H groups of SPS blocks is evident.…”

Enhanced Charge Carrier Mobility and Tailored Luminescence of n‐Type Organic Semiconductor through Block Copolymer Supramolecular Assembly

“…In order to investigate the supramolecular organization of the PBI molecules inside the block copolymer domain, wide angle X‐ray scattering (WAXS) of the bulk sample in the region θ = 1°–10° have been performed. Different types of mesomorphic structures like rods, cylinders, spheres, and lamellas are reported for surfactant‐induced assembly of block copolymer systems . Polymer supramolecular system of P4VP with small molecules like 4‐pentadecylphenol and pyrenebutyric acid through hydrogen bonding shows lamellar organization by the aggregation of the small molecule .…”