The objective of this study is to evaluate the effect of the relationship of waste polyurethane (PU) and Ethylene-Vinyl Acetate (EVA), as a replacement for conventional construction sand, on the physical properties of water absorption, bulk density and open porosity of fly ash-based and alkali-activated metakaolin mortars. By means of processing involving extrusion and milling, PU/EVA-based aggregates were prepared in three proportions: 30/70, 50/50 and 70/30. The reference alkali-activated mortars were prepared using a 1:2 (fly ash + metakaolin : conventional construction sand) ratio, by weight. The waste-containing mortars were prepared via partial replacement of construction sand with the PU/EVA waste in percentages of 10%, 20%, 30% and 40%, relative to the volume of sand. The activators used in all mortars were NaOH and Na2SiO3. The mortars were cured at 80°C for 21 hours. Based on the procedures of ASTM C 642, the water absorption, open porosity and bulk density of the alkali-activated mortars were determined at the ages of 7, 28 and 91 days. The open porosity and water absorption values ​​increased as the amount of sand replaced with PU/EVA waste increased. The absorption values ​​were found to be in the range from 8.0% to 17.00%. The values ​​obtained for open porosity varied from 20.00% to 29.00%. With regard to bulk density, the behavior was reversed: increasing the amount of sand replaced by waste, decreased the bulk density value. The values ​​ranged between 2.10 and 2.48 kg/dm3. Therefore, based on these results, mortars containing up to 40% PU/EVA have potential for use in the manufacture of non-load-bearing elements for civil construction.

The objective of this study is to evaluate the use of polyurethane (PU) coated textile wastes processed with ethylene-vinyl acetate (EVA) as lightweight aggregates in fly ash-based and alkali-activated metakaolin mortars, targeting the development of non-structural elements for civil construction. The PU/EVA waste was processed in three different proportions: 30/70, 50/50 and 70/30. Reference mortars were prepared using a 1:2 (fly ash + metakaolin: conventional construction sand) ratio, by mass. The PU/EVA-waste-containing mortars were prepared via partial replacement of natural sand with the waste in percentages of 10%, 20%, 30% and 40%, relative to the volume of the sand. The activators used in all mortars were NaOH and Na2SiO3. The mortars were cured at 80 °C for 21 hours and subsequently removed from the molds and maintained at room temperature until testing was conducted for compressive strength (at ages of 7, 28 and 91 days), leaching (7 days) and solubilization (7 days). Based on the results for compressive strength, the optimum PU/EVA content was 50% for a sand-to-waste replacement percentage of 40%. At an age of 28 days these mortars reached strengths greater than 2.5 MPa which, from a mechanical standpoint, allows for the production of non-structural elements for civil construction like sealing blocks, side walls or finish mortars. From an environmental perspective, no hazardous substances were detected in the leaching and solubilized extracts in any of the PU/EVA waste containing mortars.

RESUMONo universo da economia de materiais, do design e da sustentabilidade objetivou-se conhecer realidades brasileiras referentes ao uso de resíduos no desenvolvimento de produtos e suas relações com conceitos, normas e leis que propõem soluções para o panorama de escassez dos recursos naturais. Foram realizados pesquisa bibliográica, pesquisa documental e estudo de caso de duas empresas que utilizam resíduos naturais (madeira, pedras e conchas) e industriais (poliuretano expandido) em seus processos e produtos. Os resultados obtidos evidenciaram o desconhecimento dessas empresas mediante aos conceitos emergentes estudados e a complexidade da legislação vigente quanto à valorização de resíduos como matéria-prima. ABSTRACTIn the universe of the materials economy, design and sustainability, in this article was proposed to know the reality in Brazil about the use of waste in the product development and its relation with concepts, norms and laws that propose solutions to natural resources scarcity. It were carried out bibliographic research, documentary research and case study of two companies that use natural waste (wood, stones and shells) and industrial waste (expanded polyurethane) in the product development. The results evidenced the non-knowledge of the companies about the emerging concepts studied and the complexity of the current legislation that guides the valuation of waste as raw material in new production processes.

The problems related to environmental issues such as pollution and waste generation, and its consequences are, in many cases, linked to production processes. The current consumption of wood on a large scale stablish the trends for the use of another kind of material, into substitution of the wood: resins and special additives known like MDF (Medium Density Fiberboard). However, due to its chemical formulation, the residue of the production process of MDF and sawdust produced by your cut for the furniture industry is classified as waste Class I-Hazardous by ABNT NBR 10004:2004 standard and must have its mandatory allocation controlled. In this sense, the presentation of this work aims to present the technical feasibility for the solution of MDF waste producing a new material, using the waste structured in a PVC matrix (polyvinyl chloride). After a mechanical processing, the fraction obtained the best characteristics was the one used 35% by weight of waste MDF. The main quantitative results obtained are: the bulk density 1084 kg/ m 3 , tensile strength above 40 MPa, the maximum bending stress above of 55MPa, Charpy impact strength above 7.2 kJ/ m 2 , water absorption below 2.4% and the characteristics of nonflammability and non-flame propagation too. From an environmental aspect, the solution has a technical feasibility for the disposal of waste getting great workability products in the furniture , automotive and agribusiness industry.

Um dos grandes problemas ambientais da atualidade é o elevado volume de resíduos sólidos gerados pela indústria para suprir a demanda por bens de consumo da população mundial. Neste sentido, a apresentação deste artigo tem como objetivo apresentar cases práticos onde ocorreu a efetiva participação dos autores na utilização de resíduos industriais como matéria-prima na produção de novos produtos, alinhados ao Eco-design. Explicita ainda a importância dos ensaios preliminares para a caracterização dos resíduos, o detalhamento dos processos produtivos necessários à sua incorporação e a validação dos produtos finais em relação à sua aplicação final.