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Resumo Compósitos de polietileno verde e argila vermiculita foram desenvolvidos por meio da técnica de intercalação por fusão com o objetivo de investigar seu potencial uso como material de construção. Os compósitos foram processados em uma extrusora monorosca e moldados em uma termoprensa hidráulica. Para este trabalho, foram analisadas a resistência à propagação de chamas e os efeitos do envelhecimento natural do polietileno verde e seus compósitos. Amostras foram expostas a um ensaio de degradação abiótica durante 90 dias como forma de avaliar os efeitos das condições climáticas na morfologia e nas propriedades mecânicas do material. O teste de inflamabilidade evidenciou o efeito catalítico da argila, uma vez que para todos os compósitos avaliados, a resistência à propagação de chamas foi inferior em relação ao polímero verde puro. Os efeitos do envelhecimento natural na morfologia dos materiais foram caracterizados pela transição da matriz polimérica de um aspecto dúctil para uma aparência mais frágil e o aparecimento de vazios e de fraturas internas. Em virtude disso, o desempenho mecânico dos sistemas foi diretamente afetado, como resultado de diversos tipos de degradação abiótica sofrida pelas amostras. Abstract Green polyethylene and vermiculite clay composites were developed through the fusion intercalation technique with the aim of investigating their potential use as a building material. The composites were processed in a single screw extruder and molded in a hydraulic thermopress. For the purpose of this study, flame propagation resistance and the natural aging effects of green polyethylene and its composites were analyzed. The samples were exposed to the abiotic degradation test for 90 days with the aim of assessing the effects of climate conditions on the material’s morphology and mechanical properties. The flammability test demonstrated the catalytic effect of the clay, since for all composites evaluated, the flame propagation resistance was inferior to that of the pure green polymer. The effects of natural aging on the morphology of the materials were characterized by the transition of the polymeric matrix from a ductile aspect to a more fragile appearance and the emergence of voids and internal fractures Hence, the mechanical performance of the systems was directly affected, as a result of several types of abiotic degradation suffered by the samples.

[EN] This work reports the enhancement of the processing window and the mechanical and thermal properties of biopolymer blends of polyamide 1010 (PA1010) and bio-based high-density polyethylene (bio-HDPE) at 70/30 (wt/wt) achieved by means of natural additives. The overall performance of the binary blend melt-mixed without additives was poor due to both the relatively low thermal stability of bio-HDPE at the processing temperatures of PA1010, that is, 210¿240 ºC, and the lack or poor miscibility between the two biopolymers. Gallic acid (GA), a natural phenolic compound, was added at 0.8 parts per hundred resin (phr) of biopolymer blend to enhance the thermal stability of the green polyolefin and therefore enlarge the processing window of the binary blend. Maleinized linseed oil (MLO), a multi-functionalized vegetable oil, was then incorporated at 5 phr to compatibilize the biopolymers and its performance was also compared with that of a conventional petroleum-derived copolymer, namely, poly(ethylene-co-acrylic acid) (PE-co-AA). The resultant biopolymer blends showed a remarkable enhancement in the thermal stability and also improved toughness when both natural additives were combined. This work can potentially serve as a sound base study for the mechanical recycling of similar blends based on bio-based but non-biodegradable polymers., This research was funded by the Spanish Ministry of Science, Innovation, and Universities (MICIU) project numbers MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R. LQ-C and ST-G are recipients of an FPU grant (FPU15/03812) from the Spanish Ministry of Education, Culture, and Sports (MECD) and a Juan de la Cierva-Incorporacion contract (IJCI-2016-29675) from MICIU, respectively. The microscopy services at Universitat Politecnica de Valencia (UPV) are acknowledged for their help in collecting and analysing FESEM images.

Polymeric syntactic foams are composites made from the mixture of Hollow Glass Microspheres (HGM) and polymer matrices. One of their main characteristics is their low density and the production of these composites using a matrix derived from renewable sources potentiates their development without neglecting sustainability. In this paper , the properties of High Density Polyethylene (HDPE)/HGM syntactic foams containing 1% and 5% w/w HGM and 5% w/w of a compatibilizer are assessed. The composites were prepared by two processing routes: single screw extruder and twin screw extruder. The morphology and mechanical properties (tensile and impact) of the syntactic foams thus manufactured were ascertained. Morphological analysis indicated that matrix/filler adhesion was poor for all samples and that the best HGM dispersions were obtained in twin screw extruded samples. Mechanical properties were affected by the processing route adopted and by the content of hollow glass microspheres added. Elastic modulus, tensile strength and strain were reduced by 20, 10 and 23%, respectively, in systems processed in a twin screw extruder. Impact strength was the exception, with an increase of more than 300%. Higher contents of hollow glass microspheres led to reductions in mechanical strength of the syntactic foams, varying from 5% for the elastic modulus to 50% for strain.

Polyethylene (PE) is a polymer that has a low adhesion property, which is related to its low surface energy. However, the plasma treatment aims the modification of the surface properties without affecting the polymer structure. In this sense, the objective of this work was to prepare biocomposite films via flat extrusion with Green PE matrix and Expanded Vermiculite Clay (VMT), contents of 1, 3 and 6%. The films were treated by plasma in two different ways: Oxygen (O2) atmosphere (Condition 1); and Argon/Hydrogen (Ar/H2) atmosphere followed by a plasma treatment under O2 atmosphere (Condition 2). The results of the contact angle measurements indicated that the incorporation of VMT and the conditions used for plasma treatment increased the films wettability due to the hydrophilic character of VMT and also as a consequence of the plasma. In contrast, the XRD diffractograms indicated that there were no significant changes in the films structure.

Thermoforming is a forming technique in which petrochemical-based thermoplastics, biodegradable plastics and also plastic composites can be formed. Due to recent developments in the packaging industry, it was understood that biodegradable plastics could replace petrochemical-based engineering plastics. In this study, a biodegradable Green Polyethylene (HDPE SGF 4950, BRASKEM) was thermoformed using two different moulds. Heating temperature and time for Green PE, vacuum value, vacuum and cooling time were determined during the experimental procedure. Spherical and conical semi-finished thermoformed samples were obtained and these samples were cut in to four symmetrical pieces. Thickness measurements were achieved on some predetermined paths in quarter samples. Additionally, thickness distribution on the same paths was predicted by GEA (Geometric Element Analysis). Predicted and obtained thickness distribution results compared to each other. Finally, we have found out that GEA is not the most efficient method to obtain the thickness distribution precisely. © 2018 International Journal of Modern Manufacturing Technologies.

[EN] Green polyethylene is a new and attracting polymer from biobased resources (sugarcane) and identical properties to petroleum-based polyethylene. Its potential in the packaging industry is really promising. In this work, we report the use of different compatibilizer systems for green polyethylene (from sugarcane) and thermoplastic starch (30 wt% TPS) in order to increase ductile mechanical properties and biodegradable content. Typical petroleum-based graft copolymer of polyethylene with maleic anhydride (PE-g-MA) is used as reference compatibilizer, and new compatibilizer systems are developed using sepiolite. The obtained results show that sepiolite-based compatibilizers provide good compatibilization properties as observed by a remarkable increase in elongation at break and a noticeable size reduction of the TPS domains dispersed in the green polyethylene matrix as observed by scanning electron microscopy (SEM)., This study has been funded by the ‘‘Conselleria d’Educacio´, Cultura i Esport’’—Generalitat Valenciana (Reference number: GV/2014/008). Authors thank Tolsa S.A for kindly supply sepiolite for this study and Microscopy Services at UPV for helping in using SEM and TEM techniques.

A literatura destacada nesta pesquisa considerou que, no contexto organizacional, a inovação teve seu papel reforçado na função de contribuir para o desenvolvimento sustentável. Nesse sentido, o quadro das mudanças climáticas suscita o desenvolvimento de tecnologias sustentáveis e a obtenção de matérias-primas limpas. Dessa forma, esta pesquisa teve como foco de investigação a análise de como ocorre o processo de inovação na cadeia produtiva do plástico verde, ao se substituir um recurso não renovável (a nafta) por um renovável (etanol da cana-de-açúcar), a partir da organização focal sob a ótica da sustentabilidade. Para tanto, a pesquisa foi classificada como exploratória e descritiva e a natureza dos dados versou sobre a abordagem qualitativa. Este trabalho teve como método central o estudo de caso, que compreendeu a realização de treze entrevistas ao longo da cadeia produtiva do plástico verde (considerando a Braskem como a organização focal). A partir da perspectiva da organização focal, o diamante da inovação total foi aplicado ao objeto de estudo desta pesquisa. As características do plástico verde extrapolam a inovação de natureza tecnológica, a sustentabilidade do produto está também atrelada ao uso da matéria-prima renovável (etanol da cana-de-açúcar), evidenciando o fato de o dióxido de carbono ser capturado da atmosfera ao longo do cultivo da cana, permanecendo fixado durante o ciclo de vida do produto. O desenvolvimento dos biopolímeros justifica-se pela finitude do petróleo e de o mesmo agravar as emissões dos gases do efeito estufa. Esse desenvolvimento se deve também às vantagens climáticas tidas para produção de cana-de-açúcar e à extensão de terras disponíveis para o cultivo no território brasileiro. Com base na discussão teórica de que a organização focal é capaz de induzir a inovação em suas cadeias produtivas, buscou-se verificar quais efeitos à montante e à jusante foram desencadeados pela Braskem ao considerar a inovação do plástico verde. Dos spillovers à montante, visualizou-se que, para a produção do plástico verde, a substituição da matéria-prima provocou mudanças expressivas na cadeia suprimentos. A cana-de-açúcar conferiu à cadeia, por meio da captação do dióxido de carbono, a redução das emissões dos gases do efeito estufa. Infere-se que o Código de Conduta para os Fornecedores de Etanol da Braskem foi o principal efeito à montante desencadeado. Os principais efeitos à jusante fomentados pela organização focal conferem a importância ambiental sugerida pelo produto. Clientes potenciais foram identificados pela organização focal e, para os mesmos, foi criado o selo I’m green™, podendo ser considerado um dos principais spillovers à jusante. Na maioria dos casos, a utilização do plástico verde agrega valor aos produtos, o que pode se tornar um diferencial competitivo para as organizações que o utilizam. No caso estudado, evidenciou-se que, a partir de exemplos de ações e práticas, a política de sustentabilidade da organização focal é alicerçada nas três principais dimensões da sustentabilidade. Ademais, a partir da análise do diamante da inovação total, das características do plástico verde e das ações discutidas nos elos em termos de inovação e de sustentabilidade, pode-se avançar na discussão teórica inferindo que o plástico verde pode ser considerado uma inovação sustentável. The literature highlighted in this research considered that, in an organizational context, innovation has strengthened its role in the function of contributing to sustainable development. Thereby, the climate change scenario adds to the development of sustainable technologies and achievement of clean raw materials. This research has focused on the analysis of how the innovation process occurs in the green plastic supply chain, by replacing a non-renewable resource (naphtha from oil) for a renewable one (ethanol from sugarcane), from the focal organizational, considering the sustainability perspective. Therefore, this research was classified as exploratory and descriptive, due to its qualitative nature. The central method used was a case study; it included thirteen interviews related to the green plastic supply chain (considering Braskem as the focal organization). From the perspective of the focal organization, the diamond of the total innovation was applied to the research. The characteristics of green plastic extrapolate the nature of technological innovation. The sustainability of the product is also linked to the use of renewable input (ethanol from sugar cane), highlighting the fact that the carbon dioxide is captured from the atmosphere over the cultivation of sugarcane, remaining fixed during the life cycle of the product. The biopolymers development is justified by the oil finiteness and its aggravating the greenhouse gas emissions. This development is also due to climate advantages obtained by the production of sugarcane and the amount of available land for cultivation in Brazil. Based on the theoretical discussion of the focal organization, it is able to induce innovation in their supply chains, determining which upstream and downstream effects were initiated by Braskem to consider the green plastic innovation. Based on upstream spillovers, it was visualized that, for the green plastic production, the replacement of the raw material caused significant changes in the supply chain. The sugarcane gave to the chain, by the capture of carbon dioxide, the reduction of greenhouse gas emissions. It is inferred that the Conduct Code for Braskem Ethanol Suppliers was the main upstream factor that triggered these outcomes. The main downstream effects developed by the focal organization are related to the environmental importance suggested by this product. Potential clients have been identified by the focal organization and, for them, the I’m green™ mark was created, which can be considered a major downstream spillover. In most cases, the use of green plastic adds value to the products, which can become a competitive advantage for organizations that use it. In the case studied, it became clear that, from examples of actions and practices, the sustainability policy of the focal organization is sustained on the three main dimensions of sustainability. Moreover, from the analysis of the diamond of the total innovation, the characteristics of the green plastic and the actions discussed in innovation and sustainability perspectives, it can advance the theoretical discussion inferring that the green plastic can be considered a sustainable innovation.

We studied the biodegradation of green polyethylene (GP) by Pleurotus ostreatus. The GP was developed from renewable raw materials to help to reduce the emissions of greenhouse gases. However, little information regarding the biodegradation of GP discarded in the environment is available. P. ostreatus is a lignocellulolytic fungus that has been used in bioremediation processes for agroindustrial residues, pollutants, and recalcitrant compounds. Recently, we showed the potential of this fungus to degrade oxo-biodegradable polyethylene. GP plastic bags were exposed to sunlight for up to 120 days to induce the initial photodegradation of the polymers. After this period, no cracks, pits, or new functional groups in the structure of GP were observed. Fragments of these bags were used as the substrate for the growth of P. ostreatus. After 30 d of incubation, physical and chemical alterations in the structure of GP were observed. We conclude that the exposure of GP to sunlight and its subsequent incubation in the presence of P. ostreatus can decrease the half-life of GP and facilitate the mineralization of these polymers.