Development of a Quartz-Based Photo-Mobile Polymer Film for Controlled Motion Triggered by Light or Heat.

We have developed a photo-mobile polymer film, that combines organic and inorganic materials, to allow for controlled motion that can be triggered by light or heat. Our film is made using recycled quartz and consists of two layers: a multi-acrylate polymer layer and a layer containing oxidized 4-amino-phenol and N-Vinyl-1-Pyrrolidinone. The use of quartz in our film also gives it a high temperature resistance of at least 350 °C. When exposed to heat, the film moves in a direction that is independent of the heat source, due to its asymmetrical design. Once the heat source is removed, the film returns to its original position. ATR-FTIR measurements confirm this asymmetrical configuration. This technology may have potential applications in energy harvesting, due to the piezoelectric properties of quartz.

Depolymerization of waste poly(methyl methacrylate) scraps and purification of depolymerized products.

A big challenge for the civilization in energy saving/waste management can be "the regeneration of monomers from the waste plastics followed by their re-polymerization" using an ideal recycling method. Herein, we investigate the thermal depolymerization of poly(methyl methacrylate) (PMMA) using thermogravimetric analysis coupled with mass spectrometry (TGA-MS). In this process, the polymer chains were decomposed to methyl methacrylate (MMA) in high yield and the degradation species were thoroughly characterized. The obtained MMA contained traces of byproducts. Firstly, the byproducts were found to be nonpolymerizable, secondly, their presence interrupt the polymerization reaction, and thirdly, they reduce the quality of re-polymerized PMMA (r-PMMA). This study reclaims that besides the main byproduct (methyl isobutyrate), traces of methyl pyruvate and 2,3-butanedione were also formed during the thermal depolymerization of PMMA. The formed 2,3-butanedione was found to be responsible for the unpleasant smell in the recovered MMA that also found itself in the r-PMMA. Further, the generated byproducts were eliminated from the r-PMMA by a dissolution/re-precipitation method. The structural characterizations of the recycled and purified PMMA were carried out by Fourier-transform-infrared spectroscopy (FT-IR), Hydrogen-1 (1H)- and Carbon-13 (13C)-nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). The chemical properties of the r-PMMA and purified PMMA proved to be similar to that of the virgin commercial PMMA. This study can provide an effective and practical prototype for the recycling of waste PMMA scraps and thus reduction in pollution caused by the landfilling of waste PMMA scraps.

Ultra lightweight PMMA-based composite plates with robust super-hydrophobic surfaces.

Extremely lightweight plates made of an engineered PMMA-based composite material loaded with hollow glass micro-sized spheres, nano-sized silica particles and aluminum hydroxide prismatic micro-flakes were realized by cast molding. Their interesting bulk mechanical properties were combined to properly tailored surface topography compatible with the achievement of a superhydrophobic behavior after the deposition of a specifically designed hydrophobic coating. With this aim, we synthesized two different species of fluoromethacrylic polymers functionalized with methoxysilane anchoring groups to be covalently grafted onto the surface protruding inorganic fillers. By modulating the feed composition of the reacting monomers, it was possible to combine the hydrophobic character of the polymer with an high adhesion strength to the substrate and hence to maximize both the water contact angle (up to 157°) and the durability of the easy-to-clean effect (up to 2000 h long outdoor exposure).