Sheets of polycaprolactone (PCL) and ultra-high molecular weight polyethylene (UHMWPE) were fabricated and shaped by the Single-Point Incremental Forming process (SPIF). The performance of these biocompatible polymers in SPIF was assessed through the variation of four main parameters: the diameter of the forming tool, the spindle speed, the feed rate, and the step size based on a Box–Behnken design of experiments of four variables and three levels. The design of experiments allowed us to identify the parameters that most affect the forming of PCL and UHMWPE. The study was completed by means of a deep characterization of the thermal and structural properties of both polymers. These properties were correlated to the performance of the polymers observed in SPIF, and it was found that the polymer chains are oriented as a consequence of the SPIF processing. Moreover, by X-ray diffraction it was proved that polymer chains behave differently on each surface of the fabricated parts, since the chains on the surface in contact with the forming tool are oriented horizontally, while on the opposite surface they are oriented in the vertical direction. The unit cell of UHMWPE is distorted, passing from an orthorhombic cell to a monoclinic due to the slippage between crystallites. This slippage between crystallites was observed in both PCL and UHMWPE, and was identified as an alpha star thermal transition located in the rubbery region between the glass transition and the melting point of each polymer.

The aim of this article focuses on identifying how the addition of iron micro- and nanoparticles influences the physical properties of magnetorheological composite materials developed with a polydimethylsiloxane (PDMS) matrix with different contents of silicone oil used as additive. A number of characterization techniques have been performed in order to fully characterize the samples, such as cyclic and uniaxial extension, rheology, swelling, Vibrating sample magnetometer (VSM), X-ray Diffraction (XRD), Scanning electron microscopy (SEM), Fourier-Transform Infrared (FTIR), X-ray photoelectronic spectroscopy (XPS) and Thermogravimetric analysis (TGA). The comparison between two matrices with different shore hardnesses and their mechanical and chemical properties are elucidated by swelling and tensile tests. In fact, swelling tests showed that higher crosslink density leads to increasing elongation at break and tensile strength values for the composite materials. The best mechanical performance in the magnetorheological material was observed for those samples manufactured using a higher silicone oil content in a hard polymeric matrix. Furthermore, it has been found that the magnetic properties are enhanced when nanoparticles are used as fillers instead of microparticles.

The crystalline phase transition from tetragonal TiO₂ anatase and rutile structures to an orthorhombic unit cell of CaTiO₃ was achieved using a microwave-assisted hydrothermal process. FESEM and HRTEM Images show a well faceted CaTiO₃ rectangular-prism morphology. The use of a urea solution during the hydrothermal process allows the direct transformation of TiO₂ to perovskite-like with exposed (111) and (202) facets.

Sustainable architecture requires development of new materials with tailored optical, mechanical, and thermal properties to provide both aesthetic appeal and energy-saving functionalities. Polymers and polymer-based composites emerge as promising lightweight and conformable materials whose optical spectra can be engineered to achieve both goals. Here, we report on the development of new types of organic-inorganic films composed of ultrahigh molecular weight polyethylene with a variety of organic and inorganic nano- and micro-scale inclusions. The films simultaneously provide ultra-light weight, conformability, either visual coloring or transparency on demand, and passive thermal management via both conduction and radiation. The lightweight semi-crystalline polymer matrix yields thermal conductivity exceeding that of many metals, allowing for the lateral heat spreading and hot spots mitigation in the cases of partial illumination of films by sunlight. It also yields excellent broadband transparency, allowing for the opportunities to shape the spectral response of composite materials via targeted addition of inclusions with tailored optical spectra. We demonstrate a variety of dark- and bright-colored composite samples that exhibit reduced temperatures under direct illumination by sunlight, and outline strategies for materials design to further improve material performance.