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Recently, latex (NRL) and natural rubber (NR) from Hevea brasiliensis have emerged as promising biomaterials from renewable sources for biomedical applications. Although some attempts at commercial applications have been made, there is a need to comprehensively document the state-of-the-art of these biopolymers for biomedical applications and regenerative medicine. Here we present the recent advances in the development of NRL and NR as biomedical materials with potential properties including biocompatibility and biodegradability. Due to the angiogenic properties of NRL and NR, well-defined functional materials can be used for drug delivery systems (oral/transdermal), scaffolds for skin and bone regeneration, and dressings for wound healing. The incorporation of drugs, nanoparticles, cells, and others into NRL and NR polymer chains offers a wide range of applications such as dressings with antimicrobial activity and sustained release systems. Concluding remarks on the growth of these biomaterials for biomedical applications and regenerative medicine were discussed.

This study evaluated the thermal, morphological, chemical, and mechanical properties of virgin and recycled polystyrene. The recycling process was carried out by dissolution of polystyrene (extruded and crystal) in ethyl acetate, followed by two processes for solvent removal: vaporization by direct contact with water at 85 °C in a tubular evaporator and vaporization during the extrusion process. For the samples produced by solvent evaporation in the tubular evaporator, there was practically no degradation on polymer chain, neither reduction in glass transition temperature. For the samples produced by solvent evaporation during the extrusion, a polymer chain degradation was noted by reduction in molar weight and in glass transition temperature. The FTIR evaluation suggests that polymer oxidative degradation, in both samples, was more pronounced in the extruded sample. The removal of plasticizing additives could be evidenced by the glass transition temperature increase in the recycled samples produced in the tubular evaporator. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46208.

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Como bem apresenta e evidencia a professora Zoraide Souza Pessoa no prefácio deste livro, a problemática socioambiental contemporânea é uma questão global e urgente devido aos seus impactos em todo o mundo e que exige a atuação urgente dos mais variados setores da sociedade, tais como Estado, empresas e sociedade civil. É nesse contexto, no qual a problemática socioambiental assume um caráter de ordem global e de urgência, que as mudanças climáticas, por sua vez, assumem a centralidade nas discussões e nos debates sobre esse problema. Nesse sentido, evidenciamos que as mudanças climáticas são uma, se não a maior, das questões da problemática socioambiental contemporânea, impondo uma série de desafios às sociedades e aos ecossistemas através, por exemplo, da intensificação da ocorrência de eventos climáticos extremos. Embora as mudanças climáticas não sejam a temática central deste livro, é importante mencionar os aspectos que foram pontuados, indicando, assim, que as mudanças climáticas são um fenômeno multidimensional e que tem evidenciado ainda mais a crise socioambiental, instalada mundialmente há mais de cinco décadas, que questionou e continua questionando a construção de um planeta sustentável.

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