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Poly(butyl acrylate-co-methyl methacrylate)/clay nanocomposites were synthesized via emulsion polymerization with an emulsifier (sodium dodecyl benzene sulfonate, SDBS), an initiator (ammonium persulate, APS), acrylic acid ester monomer and Na-montmorillonite. It was found that the addition of SDBS and water widened the gap between clay layers and facilitated monomers to penetrate into clay. Through initiator, comonomers were polymerized in the montmorillonite galleries. The structure of extracted nanocomposites was confirmed by XRD, transmission electron microscopy (TEM). Their thermal property and molecule weight were investigated by differential scanning calorimetry (DSC) and gel-penetrate chromatogram (GPC).

Bulk SiO₂-based inorganic–inorganic sonogel (SG) hybrid glasses were fabricated with Ag/SiO₂ supported metal nanoparticles (MNPs). The catalyst-free SG route was implemented to produce these optically active nanostructured composites by doping the liquid sol-phase with Ag/SiO₂ synthesized according to the deposition–precipitation method. As prepared Ag/SiO₂-MNPs exhibited particle diameters below 10 nm and homogeneous size distribution. The easy and homogeneous Ag/SiO₂ loading within the micro/mesoporous SiO₂-SG network has evidenced the guest–host chemical affinity of these systems. This fact allowed us to fabricate outstanding chemically, photo-physically and mechanically stable bulk hybrid monoliths with controllable geometry and doping rates, suitable for linear and nonlinear optical (NLO)–spectroscopic characterizations. Indeed, the hosting SG matrix provided an elevated thermal and mechanical stability protecting the reactive Ag nanoparticles from environment conditions, diminishing their tendency to from aggregates and, above all, preserving their pristine photophysical properties. Comprehensive morphological, structural, spectroscopic and NLO characterizations were performed on the obtained SiO₂:(Ag/SiO₂) hybrid composites. Results have shown that the nanocrystalline (NC) properties, multipolar nature and small sizes of the implemented Ag/SiO₂-nanoparticles, together with the bulk guest–host mechanical interactions, play a crucial role for the observation of outstanding spectroscopic and quadratic NLO properties of the developed hybrid systems.

New hybrid (organic–inorganic) material based on nanocrystalline CdSe capped with EDTA and poly(O-toluidine) doped with camphor sulfonic acid (POT-CSA) is processed from solution and characterized in order to relate the device function (optical absorption, charge separation and transport properties) to active-layer properties and device parameters. POT/CdSe hybrid material has been synthesized using physical mixing method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to investigate the structural and morphological properties. The organic–inorganic composite system was applied as an active device component to demonstrate the electrical memory effects. The device exhibited a nonvolatile, resistive switching performance with a constant ON–OFF current ratio. The nonvolatile behavior was confirmed by applying a 2.5-V read pulse.

In the present review, we show how the chemical variability of phthalocyanines allowed to synthesize a broad range of hybrid materials. The combination of phthalocyanines or related derivatives with polymers or carbonaceous materials led to efficient chemical sensors. It is shown how the incorporation of macrocyclic molecules in hybrid materials highly modifies the structural and morphological characteristics of the materials. Rugosity, specific surface and porosity being key parameters in the analyte-sensing material interactions, these modifications highly improve the performance of chemical sensors. This is the reason why they are particularly promising materials for the development of new chemical sensors, associated with electrochemical, conductometric or optical transducers.

The aggregation properties of two peptide–porphyrin conjugates were investigated by optical spectroscopy and microscopy imaging with nanometer resolution. Specifically, a tetraphenylporphyrin platform was functionalized by (L)-magainin, a 23-residue long antimicrobial peptide, and by a (L)-magainin analogue differing from the parent peptide by a single residue substitution, $i.e.$ an Ala vs. Phe replacement in the position 5 of the peptide chain. Spectroscopic and microscopy results show that this single-site substitution has a small effect on the secondary structure attained by the two peptide analogues, but deeply affects the morphology of the mesoscopic structures deposited on hydrophilic mica from methanol/water solutions. In particular, only the Ala-substituted peptide-porphyrin conjugate was shown to be able to form micrometric fibrils, coating homogeneously a hydrophilic mica surface. These results pave the way for potential applications of porphyrin-peptide compounds in localized photodynamic therapy and for designing solid-state stereoselective sensors.

The electrical and dielectric properties of the compound C₇H₁₂N₂[H₂PO₄]₂ ⋅ 1/2H₂O were investigated by the complex impedance spectroscopy, over a wide range of frequencies and temperatures, 600 Hz–5 MHz and 303–408 K, respectively. Besides, a detailed analysis of the impedance spectrum suggested that the electrical properties of the material at several temperatures and the electrical equivalent circuit have been proposed to explain the impedance results. Concerning the Nyquist plots, they clearly showed the presence of bulk and grain boundary. As for the imaginary part of modulus at several temperatures, it shows double relaxation peaks, thus suggesting the presence of grains and grain boundary conductions in the sample.

Thermal residual stresses (TRS) in hybrid materials and structures occur by the mismatch of thermal expansion of different materials. Especially when combining metals with carbon fiber reinforced plastics (CFRP), a significant level of internal stresses can be reached. High processing temperatures and high stiffness of the constituents are also responsible for high stress levels. Laminates of thermoplastic CFRP (unidirectional carbon fiber reinforced polyamide 6) and stainless steel foils are a suitable material system to examine the TRS in detail. Since TRSs in the steel fraction are of tensile nature, these superpose to externally applied loads, resulting in higher efforts for the material and thus reduced lifetimes under cyclic fatigue loading. Therefore, a reduction of TRS is desired. Two methods for TRS reduction were applied, and its influence on fatigue lifetime was investigated. Firstly, specimens were stretched by a preloading to reduce TRS by yielding of the metal. Secondly, non-symmetric laminates were gradually cooled down after consolidation to compensate TRS formation by non-symmetric shrinkage. While preloading of materials and structures is known for TRS modification, the gradually cooling is not established, yet. Both modification principles were numerically investigated before experimental validation. A significant increase of lifetime was reached by TRS reduction.

In this paper, a molecular level hybrid material consists of glycidyl-polyhedral oligomeric silsesquioxanes (G-POSS) and bisphenol-A epoxy resin (EP) with chemical bonds connection was prepared. The curing reaction and surface characteristics of the hybrid materials were investigated by differential scanning calorimetry (DSC) and scanning electron microscope (SEM), respectively. With the increase in the loading of G-POSS, the Activation Energy (Ea) shows significant decrease and the mechanical properties of the EP were greatly improved. The EDS results revealed a uniform dispersion of the G-POSS in the hybrid materials. The G-POSS/EP composites exhibited excellent dielectric properties and thermal properties due to the voids volume in the composites. The results manifested that the introduction of G-POSS to EP exhibited excellent toughening and reinforcing effects on the composites.