Concerns for the environment are recurrent in our society, and research on low impact materials such as those produced from waste is an alternative. This work is based on the reuse of scrap paper and rice hulls aiming to increase the life cycle of these waste products and to find better destination. Composites with a volumetric filler content (dispersed phase) of 80% were produced via compression molding using polyurethane (PU) based on castor oil or polyester resin as matrix, in four distinct families: polyester/rice hulls, PU/rice hulls, polyester/paper and PU/paper. The following tests were performed: water sorption, contact angle, hardness, impact and tensile testing. Scanning electron microscopy (SEM) was used for fracture morphology study. Basic visual analysis showed greater void content for the rice hull composites, making them less aesthetically appealing compared to paper. It was observed in the case of PU matrix the filler greatly influenced the rigidity since this pure material was more flexible compared to pure polyester. Filler incorporation decreased tensile strength of the polyester matrix but significantly increased that of the PU matrix.

This study aimed to analyze the waterproofing MDF with different coatings. For this, a comparative study was conducted with the following coatings on MDF: Vegetable polyurethane resin on castor oil-based, acrylic lacquer and marine varnish. To carry out the research, sewed up the samples in sequence, they received the coatings, and then we performed the test water absorption. As a result, the polyurethane resin to castor oil-based coating was presented the best results, that is, lower levels of water absorption lower thickness swelling and volume. Finally, it is believed that the study of waterproofing MDF plant originated from polyurethane castor oil is beneficial because it is a renewable source of material.

This paper focuses on the investigation of degradation effects from the environment on waste paper/polyester composites. The materials were analyzed according to visual aspects, mass gain and mechanical properties. The composites subjected to aging were influenced by moisture absorption from the particles, with a deleterious effect also on particle/matrix interface, decreasing tensile and flexural strength of the composite. This same phenomenon lead to a positive effect on impact strength and reduction in hardness of the composites, since moisture absorption was limited and the material became slightly tougher. Moisture absorption also caused an increase in elastic modulus of the matrix. Based on all results, the developed material was found not suitable for external use.

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Ela é servidora pública lotada na Gráfica UFRGS. Durante sua trajetória na universidade, como diretora da Gráfica da UFRGS, adquiriu experiência na produção gráfica, gestão de pessoas, ecodesign, coordenação de projetos de extensão, visando melhorias dos processos produtivos da Gráfica, sustentabilidade e inovação. E esse conhecimento adquirido foi fundamental para que ela desenvolvesse o seu doutorado na própria Universidade Federal do Rio Grande do Sul (UFRGS) no programa de Pós-Graduação em Design, na qual pesquisou possíveis soluções para o reaproveitamento do resíduo de papel descartado pela Gráfica UFRGS. <00006708@ufrgs.br>Abstract This research presents an alternative material that follows innovative and sustainable standards constituted by the union of the gelatinized starch matrix with paper waste as load. Since starch and paper are hydrophilic nature, limitations in the applications of this biocomposite may occur if no barrier is created to restrict moisture absorption. For this, waterproofing tests were performed to analyze the behavior of the material in relation to water absorption (2 and 24 hours) with four different waterproofing agents applying one, two and three layer. Satisfactory results were obtained from the second coat in 2 h and third coat in 24 h with the polyurethane based waterproofing agents. Therefore, comparing to the other waterproofing agents tested, and searching for more sustainable results, it can be concluded that the polyurethane-based waterproofing agent of vegetable origin proved to be the one that best meets the objectives of this research. Estudio sobre la impermeabilización del compuesto de almidón / papel de desechoResumen Esta investigación presenta un material alternativo que sigue estándares innovadores y sostenibles constituidos por la unión de la matriz de almidón gelatinizado con una carga de residuos de papel. Teniendo en cuenta que el almidón y el papel tienen una naturaleza hidrófila, puede haber limitaciones en las aplicaciones de este biocompuesto si no se crea una barrera para restringir la absorción de humedad. Para este fin, se realizaron pruebas de impermeabilización para analizar el comportamiento del material en relación con la absorción de agua (2 y 24 horas) con cuatro agentes impermeabilizantes diferentes con una, dos y tres capas. Se obtuvieron resultados satisfactorios de la segunda capa en 2 horas y la tercera capa en 24 horas, con productos impermeabilizantes a base de poliuretano. Por lo tanto, en comparación con la otra impermeabilización probada y buscando resultados más sostenibles, se puede concluir que la impermeabilización a base de poliuretano a base de plantas demostró ser la que mejor cumple con los objetivos de esta investigación.Palabras clave Biocompuesto, Almidón, Residuos de papel, Impermeabilización, Absorción de agua.