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Water pollution is one of the biggest environmental issues of our times. To address such a huge challenge, the full involvement of everyone is required. In this context, we report the results of outreach hands-on activities aimed at presenting to the general public two classes of materials with high potential in the removal of common water pollutants, such as heavy metals and dyes: zeolites and chitosan-based aerogels. Under the guidance of young students of materials science and engineering, participants have performed safe, fast, and easy to understand experiments for the removal of copper ions and dye molecules from water. The discussion of the results, which was adapted time by time to the knowledge and age of the audience, provided all participants with a general understanding of the two phenomena underlying water purification, namely, ion exchange for zeolites and molecular adsorption for chitosan aerogels. Besides raising awareness of young people about water pollution and, more in general, about environmental issues, the proposed activity highlights the key role of materials scientists in providing smart and feasible solutions to tackle everyday problems.

Viscoelastic relaxation measurements on styrene-butadiene rubbers (SBRs) doped with carbon nanotube (CNT) at different concentrations around the sol-gel transition show the time–temperature superposition (TTS). This process is described in terms of the mode coupling theory (MCT) approach to viscoelasticity by considering the frequency behavior of the loss modulus E ″ (ω) and showing that the corresponding TTS is linked to ω 1 / 2 decay. From the analysis of the obtained data, we observe that the interaction between SBRs and CNT determines different levels of decay according to their concentration. Systems with the lowest CNT concentration are only characterized in the studied T-range by their fragile glass-forming behavior. However, at a specific temperature T L , those with the highest CNT concentration show a crossover towards pure Arrhenius that, according to the MCT, indicates the presence of kinetic glass transition (KGT), where system response functions are characterized by scaling behaviors. [ABSTRACT FROM AUTHOR]

Phase behavior modulation of liquid crystalline molecules can be addressed by structural modification at molecular level. Starting from a rigid rod‐like core reduction of the symmetry or increase of the steric hindrance by different substituents generally reduces the clearing temperature. Similar approaches can be explored to modulate the properties of liquid crystalline networks (LCNs)—shape‐changing materials employed as actuators in many fields. Depending on the application, the polymer properties have to be adjusted in terms of force developed under stimuli, kinetics of actuation, elasticity, and resistance to specific loads. In this work, the crosslinker modification at molecular level is explored towards the optimization of LCN properties as light‐responsive artificial muscles. The synthesis and characterization of photopolymerizable crosslinkers, bearing different lateral groups on the aromatic core is reported. Such molecules are able to strongly modulate the material mechanical properties, such as kinetics and maximum tension under light actuation, opening up to interesting materials for biomedical applications. [ABSTRACT FROM AUTHOR]

The study of the reinforcement network in elastomer compounds is one of the most relevant issues for the application of these materials because their properties are strongly dependent on the obtained morphology. To this regard, the viscoelastic and dielectric behavior of vulcanized styrene butadiene rubber (SBR) reinforced with different amounts of carbon nanotubes (CNT) have been investigated and compared with the vulcanized unfilled SBR and the vulcanized SBR samples reinforced with a conventional amount of carbon black (40 phr). Differential scanning calorimetry (DSC) measurements have been carried out to highlight possible differences of the glass transition temperatures for all the reinforced compounds. The percolation threshold value of the nanocomposite samples has been estimated by dielectric analysis. Finally, dynamic mechanical analysis (DMA) measurements have been performed in tensile mode in the temperature range of −60 to 80 °C to obtain both E′ and E′′. From these experimental data, the master curve for each sample has been estimated by using the time–temperature superposition principle in combination with the vertical shift approach. From the analysis of this latter, the activation energy, associated to the thermal movement of the reinforcement network, has been calculated to better elucidate the reinforcement mechanism in the nanocomposites. [ABSTRACT FROM AUTHOR]

The design of thermosetting materials needs to account for their environmental impact, both in the production and the end‐of‐life phases. In this study, the furan/maleimide Diels‐Alder (DA) chemistry is exploited to develop reprocessable and self‐healing networks. In particular, an epoxy monomer is first functionalized with furanic molecules obtaining DA precursors in which the diene moiety is either a pendant or a terminal group. These precursors are mixed at different relative ratios and then crosslinked with 4,4′‐bismaleimido‐diphenylmethane. The reversible nature of the formed network is investigated by thermal and dynamic‐mechanical analysis. Then the effect of the formulation, in terms of DA network architecture, on the mechanical properties and reprocessability of the resulting crosslinked materials is studied. In detail, the flexural behavior of the as‐prepared samples and reprocessed ones is evaluated, highlighting the influence of composition on the recycling efficiency. [ABSTRACT FROM AUTHOR]