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The prioritization of agroindustry fiber wastes as raw materials in development of composites has become a challenge to obtain higher value-added products with targeted applications. In this study, natural fiber-reinforced polymer matrix composites were elaborated using two fiber sizes (605 μm and 633 μm) of oil palm empty fruit bunch (OPEFB) and acrylic thermoplastic resin. In doing so, resin and fibers were mixed at room temperature by maintaining filler content of 42 wt. % for all formulations. In addition, thermomechanical compression moulding was used as composite manufacturing process at four processing temperatures (80, 100, 120, and 140°C). All formulations were subsequently exposed to salt fog spray aging for 330 hours. The effects of accelerated aging process on mechanical, spectrophotometric, and thermogravimetric characteristics were studied. On the whole, results have shown feasibility to use a facile method to elaborate composites based on waterborne acrylic matrix and OPEFB fibers. After salt spray testing, it was observed detectable levels of Aspergillus spp. of fungi in all samples, as a result of phylogenetic organization of microbial activity. Tensile behavior of composites was significantly influenced by processing temperature and fiber size. In broad terms, their overall mechanical properties were improved by the increase of temperature. Additionally, infrared spectroscopy results showed important bands mainly associated to biodegradation of cellulose, hemicellulose, and lignin. On the other hand, two degradation stages were mainly identified in thermogravimetric evaluation. Noteworthy, aging had no significant effect on the thermal properties of composites.

Although several reports can be found in the literature about the recycling of plastic materials, only a few focus on recovering and molding them in a new process. Plastic material blends can be fabricated using several techniques, which allows the molding of a compound adaptable to each needed performance. This fact favors the recycling by allowing the use of mixed wastes without major processes, avoiding expensive treatments. This research work analyzes the mechanical properties of a material conformed by 100% recycled plastics: polyethylene terephthalate and low-/high-density polyethylene without previous separation or washing and drying pretreatments. Its macro and microscopic structure was studied and described, and formulations of different compound rates were analyzed. Mechanical resistance was around 60% of a material composed of virgin materials in compressive, flexural, and tensile strength tests. Its potential application to building components manufacture is analyzed.

[reaction: see text] Tricyclic 4-ethyl-5-thioxo-3H,5H-bis[1,2]dithiolo[3,4-d][4,3-b]pyrrol-3-one and monocyclic 3H-1,2-dithiole-3-thione derivatives reacted with Fischer carbene complexes, giving 1,3-dithiin dithioortho esters through insertion of the carbenic carbon into the S-S bond next to the thiocarbonyl function of the substrate.

The general objective of this research work was to contribute to the environmental decontamination. Its specific objective was to develop sustainable roofing tiles from the ecological, technical and economical points of view.These roofing tiles are made from recycled materials such as plastics from industry, and rubber from tires into disuse. In this way this technology contributes in the decontamination of the environment, since it uses waste materials that are buried in municipal land without any use, or accumulated and burned in landfills, causing pollution. The procedure used was the thermo-molding compaction. The available amounts of plastic waste are abundant. According to data provided in 2012 by the Ministry of Health and Environment of Argentina, Argentina produces 1,639 tons / year. The available amounts of rubber tires are also abundant. According to data provided in 2012 by the National Institute of Industrial Technology -INTI, Argentina generates more than 100,000 tons / year. Plastics and rubber are non bio-degradables materials, so nature can not absorb them as other waste. One purpose of this research work was to provide an alternative to other traditional building technologies that consume non-renewable resources, or produce negative environmental impact. The main technical advantages of these roofing tiles respect to other traditional such as ceramic or concrete tiles are their excellent resistance to hail and freezing, high flexural resistance, low specific weight, and low water absorption.

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