In this article, we report the formation of micelles from a tetrathiafulvalene (TTF) end-functionalized poly(N-isopropylacrylamide) (poly(NIPAM)) derivative (1). We have determined the critical aggregation concentration (CAC) and average diameter of the micelles using fluorescence spectroscopy and dynamic light scattering experiments, respectively. We have exploited the NIPAM backbone of the polymer to thermally transform the swollen hydrophilic poly(NIPAM) derivative to a more globular hydrophobic state at the lower critical solution temperature (LCST). Finally, we have shown that we can exploit the chemical oxidation and complexation properties of the TTF unit to disrupt the micelle architecture to release the hydrophobic dye Nile Red from the interior of the micelle.

A new class of polymeric thermometers with a memory function is reported that is based on the supramolecular host–guest interactions of poly(N‐isopropylacrylamide) (PNIPAM) with side‐chain naphthalene guest moieties and the tetracationic macrocycle cyclobis(paraquat‐p‐phenylene) (CBPQT4+) as the host. This supramolecular thermometer exhibits a memory function for the thermal history of the solution, which arises from the large hysteresis of the thermoresponsive LCST phase transition (LCST=lower critical solution temperature). This hysteresis is based on the formation of a metastable soluble state that consists of the PNIPAM–CBPQT4+ host–guest complex. When heated above the transition temperature, the polymer collapses, and the host–guest interactions are disrupted, making the polymer more hydrophobic and less soluble in water. Aside from providing fundamental insights into the kinetic control of supramolecular assemblies, the developed thermometer with a memory function might find use in applications spanning the physical and biological sciences.

This paper presents the synthesis, the structural determination and the sensing capabilities toward Volatile Organic Compounds (VOCs) of a new class of fluorescent indolizine-cyclodextrin sensors. Two different pathways, both involving bipyridinium ylides and 6-amino-b-cyclodextrin, have been used to carry out the synthesis of these sensors. The macrocycle structures were dominantly established by 1H-NMR spectra and systematically studied by molecular modelling (MM3, AM1, AM1-COSMO methods). The sensing capabilities of the sensors were evaluated by emission of fluorescence, during the inclusion of the guest (adamantanol or aromatic derivatives) into the cyclodextrin (CD) host cavity. The host/guest complex formation was investigated by formation constant determinations, using experimental methods, coupled with theoretical calculations of formation energies using a specific docking procedure. Both experimental and theoretical results suggest that some compounds would make very attractive sensors for VOC detection. Some compounds could also be taken into consideration as biological markers.

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The aqueous solution properties of amphiphilic tetrathiafulvalene (TTF) end-functionalized poly(N-isopropylacrylamide) (PNIPAM) derivative 1 have been studied. Fluorescence spectroscopy, dynamic light scattering (DLS) and differential scanning calorimetry (Nano-DSC) were used to monitor the temperature-induced micellization and showed that 1 underwent two successive phase transitions corresponding to unimer-to-micelle and lower critical solution temperature (LCST) transitions, respectively. We have investigated the complexation properties of the TTF unit toward cyclobis(paraquat-pphenylene) (CBPQT 4+ ) or the randomly methylated β-cyclodextrin (RAMEB) to manipulate the amphiphilicity of 1 and to control the unimer-to-micelle phase transition by forming pseudorotaxane-like architectures. For the RAMEB complex with 1, the addition of a competitive guest such as 1-adamantanol resulted in the restoration of amphiphilicity of polymer 1 and consequently the reformation of micelles.

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The reversible addition−fragmentation chain transfer (RAFT) polymerization technique has been employed to synthesize various linear tetrathiafulvalene end-functionalized polymers. n-Butyl acrylate, N-isopropylacrylamide, and styrene monomers were polymerized in the presence of azobis(isobutyronitrile) and a new tetrathiafulvalene (TTF) trithiocarbonate derivative as reversible chain transfer agent. All RAFT polymerizations exhibited pseudo-first-order kinetics, a linear increase of the number-average molar mass (M n SEC) with conversion and narrow molar mass distributions (polydispersity <1.3). The resulting homopolymers exhibited α-TTF and ω-trithiocarbonyl end groups. Cyclic voltammetry was used to investigate the electrochemical properties of the TTF polymers. Finally, we have shown that the TTF moiety at the α-chain-end could be specifically modified by complex formation with the tetracationic cyclophane cyclobis(paraquat-p-phenylene) (CBPQT4+) in organic media. Electrochemical oxidation of the TTF moiety resulted in disassembly of the polymer inclusion complex (PIC).