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We prepared composites of recycled polypropylene and construction debris aiming to obtain a sustainable hybrid material, with prospective application in the construction industry. We varied the amount of debris in 0, 1, 2, 3 and 7 m/m/% and the compounded materials were analysed by scanning electron microscopy, thermogravimetry/derivative thermogravimetry, differential scanning calorimetry, Fourier-transform infrared spectroscopy, melt flow rate, wide angle X-ray diffractometry, nuclear magnetic resonance relaxation time and dynamic mechanical analysis. The melt flow rate varied non-linearly according to the debris content. The thermal stability of recycled polypropylene was slightly improved due to the presence of debris particles. The degree of crystallinity of the recycled polypropylene also showed a non-linear change, and we noticed some transcrystallization phenomenon in the polymeric matrix. The glass transition temperature decreased for all composites, denoting an increase in the segmental mobility of the polymeric chains. Considering the domains curves of the nuclear magnetic resonance, there was some interaction between polymer and debris particles, mainly ascribed to the nanometric portion of the hybrid debris particles. We concluded that this hybrid composite may become of great interest to the construction industry, used as replacement for closing boards.

The great diversity of plant species in pastures of the Brazilian Cerrado with distinct ecophysiological characteristics indicates the possibility of finding, in the cellular content of this flora, chemical compounds with potential for use in agriculture and human and animal health. Three steps are necessary to prove this hypothesis: phytochemical prospecting, characterization of secondary metabolites, and studies on the biological activities of these metabolites present in these plants.The chemical profile of secondary metabolites present in five species of the Brazilian Cerrado (Davilla elliptica, Remijia ferruginea, Luehea paniculata, Anacardium occidentale, and Acosmium dasycarpum) was traced in this research. These plant species were collected in pasture areas of Felício dos Santos, Minas Gerais. The samples were dried and submitted to two types of extract (ethanolic and hexanic). By using specific chemical reactions, the presence of coumarins, triterpenes/steroids, and anthracenosides was observed in the hexanic extracts, while the presence of alkaloids, triterpenes/steroids, flavonoids, tannins, reducing compounds, and anthocyanins was observed in the ethanolic extracts. The species presented diverse classes of compounds. However, triterpenes/steroids, tannins, reducing compounds and anthocyanins were found in all species, being the use of the solvent ethanol the most efficient in extracting the compounds. The species D. elliptica presented the highest number of classes of compounds. The widespread application in folk medicine justifies further studies on the biological activity of different metabolites in agriculture and health areas.

The knowledge of the processes that affect soil herbicide behavior allows to developing practices that improve efficiency in chemical weed control and reduce the negative impacts of cropping-systems. In this research, we used HPLC to determine sorption and desorption of clomazone in Brazilian soil samples (Red-Yellow Latosol with liming and without liming, Red latosol with and without liming, and Organosol). To study clomazone sorption, we used the batch equilibrium method. Clomazone concentrations in soil samples were determined by HPLC. Desorption was quantitated using the samples contained in tubes after sorption testing, repeating the steps followed to quantify sorption. The Freundlich isotherm adequately describe clomazone sorption in all soils. Variation in pH in Red-Yellow Latosol and Red Latosol did not change clomazone sorption. The values of the Freundlich constant (Kf) indicate that clomazone sorption is higher in Organosol, followed by Red latosol (with liming) = Red latosol (without liming) > Red-Yellow Latosol (with liming) = Red-Yellow Latosol (without liming). We conclude that among the attributes evaluated, soil organic matter has the highest impact on clomazone sorption. There was a direct relationship between Kf values and organic matter content of the substrates. Desorption of clomazone was very low in the evaluated soils, with the exception of Organosol, where quantification of the herbicide was possible.

The influence of polycaprolactone (PCL) and nano titanium phosphate, pristine (TiP) and Jeffamine™ modified (JETiP), was investigated in composites derived from recycled polypropylene/polycaprolactone/titanium phosphate (PPr/PCL/TiP and PPr/PCL/JETiP). The TiP was synthesized and chemically modified with amine and the composite processed in a Haake rheometer. Improvement of PPr thermal stability was revealed. Reduction of PPr cooling crystallization temperature (9°C) and crystallinity degree (∼5–10%) were registered. Hydrogen nuclear magnetic resonance time domain revealed enhance of molecular mobility which was associated to the diminution of PPr crystallinity. The X-ray diffraction pattern of the composite PPr/PCL/JETiP did not show phosphate diffraction angle. It was understood as polymer intercalation into modified titanium phosphate galleries. At low temperature, the storage modulus increased by the presence of PCL and phosphates evidencing reinforcement. Both PPr/PCL/TiP and PPr/PCL/JETiP composites yielded phase separation systems revealed by two peaks in the loss modulus curves. Also, the high PPr participation effectiveness degree on the PCL-rich phase was understood as owing to the interaction between PCL and phosphates.

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