A new alkoxysilane was used to reduce the hydrophilic character of the silica used in reinforcing styrene/butadiene elastomers for the tyre industry. The surface properties of silica modified with 17 wt.‐% of this silane were estimated by inverse GC. A clear change from hydrophilic to hydrophobic character was observed. Styrene/butadiene copolymers loaded with modified silicas were characterized were characterized using vulcanization tests, stress/strain measurements and morphological analysis. The best tensile properties were obtained with TESPT‐modified silica. The properties of the compound loaded with sb1‐pre‐grafted silica are scantily lower that the ones of the other compounds. This difference must be ascribed to a higher crosslink density given by the sulfur deriving from the TESPT decomposition during the vulcanization process. magnified image

Hybrid thiol‐ene/epoxy coatings were prepared by combining thiol‐ene photo‐curable formulations with epoxy monomers, through a dual UV–thermal curing process. An increase in glass transition temperature and in storage modulus was observed for the hybrid thiol‐ene/epoxy coatings when compared with the pristine thiol‐ene UV‐cured system. Also, the bisphenol A moieties introduced into the hybrid networks during the dual‐curing process induced an increase in thermal stability of the cured materials. It has been demonstrated that the addition of epoxy monomer to the thiol‐ene photo‐curable system is a good strategy to follow in order to improve the final properties of thiol‐ene‐based coatings leading to a wide range of possible applications for the hybrid materials. Copyright © 2010 Society of Chemical Industry

This article aims to prepare by injection molding recycled polymeric composites based on PA66 reinforced with short carbon fibers after artificial aging for applications in the automotive field. The aging cycles involves the combined action of UV radiation, moisture, and temperature in order to simulate the common outdoor conditions. The 100% recycled composites are obtained by the regranulation of the aged specimens followed by the remelting and re-injection molding. The study is focused on the comparison between the mechanical behavior and the microstructure of the composites before and after mechanical recycling. The results of mechanical, thermal, and morphological investigations reveal that the recycling process had no significant effect on the final properties and microstructure of the recycled composites. Therefore the recycled PA66CF30 composites could be successfully used for structural or semi-structural automotive applications guaranteeing good final performances and advantages from the environmental point of view.

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Polypropylene (PP), acrylonitrile butadiene styrene (ABS), and thermoplastic polyurethane (TPU) nanocomposites filled with 5 wt % of two different kinds of commercially available graphene nanoplatelets (GNPs) were prepared. Composites materials were characterized in terms of thermal properties (thermal conductivity and thermal stability) in order to study the effect of different fillers within different thermoplastic matrices. The exfoliation process and the mechanical properties were also investigated. We chose three different thermoplastic polymers (polyolefin, copolymer and elastomer) to cover a wide range of thermoplastic materials and identify a guideline in the use of GNPs for nanocomposite materials. No drastic differences were observed in terms of mechanical properties when the same matrices were filled with different GNPs. Concerning thermal conductivity, it was observed that the GNPs plane dimensions play a crucial role in the increase of conductive properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44814.

The aim of the work was to investigate the effect of recycling on the mechanical behaviour of polypropylene composites reinforced with glass fibres (GFs), starting from a material already used in automotive for vehicle components, obtained by injection moulding. Formerly specimens of pristine composites were subjected to tensile and flexural tests, then the specimens were grinded, reprocessed and recycled only once. The recycled composites showed a slight decrease in the elastic modulus and tensile and flexural strength values. Morphological investigations, carried out by scanning electron microscopy and optical microscopy, were also performed to study the microstructure and the fibre–polymer interfaces, together with the GFs’ orientation and distribution within the polymeric matrix before and after the mechanical recycling. The results revealed that the mechanical recycling had no significant effect on the final microstructure and performance of the fully recycled composites, which can be still successfully used for structural applications in the automotive field.

Hybrid nanocomposite coatings were prepared by the UV‐curing technique with a methacrylic oligomer and multifunctional methacrylic polyhedral oligomeric silsesquioxane blocks (POSS®). The results obtained from the polyhedral compounds were compared with those of a disordered framework obtained by the condensation of a silica precursor (MEMO). The inorganic domains generated during synthesis created constraints in movement of polymer segments, which reflected in an increase in Tg of the hybrid nanocomposite coatings. The films were transparent. The random structure obtained by the condensation of the MEMO showed a stronger effect on Tg than that observed by introducing POSS®. The effect of inorganic domains reflected on thermal stability, surface hardness and mechanical properties of the hybrid nano‐composite coatings.magnified image

Metal-free conductive tracks were obtained by laser printing on a polypropylene matrix by adding MW-CNTs.