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Resumo: A substituição da tecnologia CRT (cathode ray tube) utilizada em televisores e monitores, há mais de 60 anos, pelas novas tecnologias de Plasma, LCD (liquid crystal display) e LED (light-emitting diode) tem gerado grande quantidade de resíduos. Não existem estatísticas oficiais da quantidade de resíduos gerados no Brasil, contudo, para alguns países, como os EUA, a China e Taiwan, estimam-se descartes anuais de 3,2 milhões, 5 milhões e 1 milhão de televisores e monitores, respectivamente. Os monitores são compostos por polímeros, metais e cerâmicas, incluindo alguns materiais tóxicos. Este trabalho está focado na caracterização e reciclagem da carcaça polimérica dos monitores CRT. Foram coletados monitores danificados ou obsoletos e as carcaças foram separadas por marca, caracterizadas, cominuídas e injetadas para obter corpos de provas para os ensaios mecânicos. A caracterização mostrou que as carcaças, independentemente da marca, utilizam o mesmo material polimérico, o ABS (Acrilonitrila Butadieno Estireno). Os resultados dos ensaios mecânicos apresentaram variações nas diferentes marcas, provavelmente por possuírem composições diferenciadas. Esta variação também foi verificada analisando a superfície de fratura dos corpos de prova após o ensaio de tração. Com base nos resultados pode-se concluir que o material reciclado apresentou desempenho mecânico satisfatório, viabilizando tecnicamente a sua reciclagem. Palavras-chave: Monitor CRT, carcaça polimérica, reciclagem mecânica. Recycling of Frames of Monitors: Mechanical and Morphological PropertiesAbstract: The cathode ray tube (CRT) technology-used in televisions and monitors for more than 60 years-has generated a lot of waste, now that is has been replaced by newer technologies such as plasma, liquid crystal display (LCD), and light-emitting diodes (LED). There are no official statistics on the amount of waste generated in Brazil; however, for some countries, such as the United States, China, and Taiwan, the estimated annual disposal of televisions and monitors is 3.2 million, 5 million, and 1 million, respectively. Monitors mainly contain polymers, metals, and ceramics, some of which may be hazardous. This work is focused on characterization and recycling of polymeric frames of CRT monitors. Monitors, damaged and obsolete, were collected and separated by brand, comminuted, and then injected to obtain the samples to be used in mechanical tests. The results pointed to the same polymeric material being used, viz. acrylonitrile butadiene styrene (ABS), regardless of the brand. The mechanical properties varied across different brands, probably because of different compositions. This variation was also observed in the analysis of the fracture surface of the samples after the tensile test. On the basis of the results, it can be concluded that the recycled material showed satisfactory mechanical performance, enabling recycling technically.

The focus of this study is to evaluate the efficiency of oxidation processes in the treatment of a solution containing Rhodamine-B (RhB) used in various industrial applications. The advanced oxidation processes of electrooxidation (EO) and photoelectrooxidation (PEO) were used. At the same time, direct photolysis (DP) was also applied. Total organic carbon (TOC) reduction and color removal were evaluated. There was an efficient color removal when DP was performed, and the color removal efficiency was the highest when NaCl was used as supporting electrolyte for PEO and EO. However, the TOC reduction was low, indicating that the degradation of the color does not correspond to the pollutant mineralization.

The recycling of polymeric waste has attracted considerable interest and many efforts have been made to facilitate large scale recycling. The rapid evolution of technology has generated large volumes of obsolete and unusable polymeric products. One example is the CRT (cathode ray tubes) monitor that are rapidly being replaced by monitor types such as LCD, LED and Plasma. The present materials and routes for recycling this waste is not well known, which encourages studies in this area. The main objective of this work is to identify the type of polymer present in the CRT monitor frames and evaluate if the quality of the recycled polymer is changed according to the monitor age (year of manufacture). Monitors of different years of manufacture but the same brand were collected and disassembled. Frames were separated into two groups (older and younger). After, the frames were comminuted and samples were injected, according to ASTM D638-08. The samples were characterized by infrared, density, mechanical, MEV and TGA tests. The results obtained by infrared (FTIR) showed that regardless of the year of manufacture the monitor frames are produced with the same polymeric material, which was identified as copolymer ABS (acrylonitrile butadiene styrene). The results of mechanical and thermal tests showed that, in general, the recycled ABS polymers regardless of the year of manufacture showed no significant losses in their properties. However, it was found, by the TGA test, that there was a small variation in polymer composition.

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Initially the development of a third distinct variety of telephone drop wire was undertaken to combine the complexities of the reinforced neoprene array with the simplicities of a PVC drop wire construction. In addition, at no time could the excellent properties be sacrificed for manufacturing convenience. In the final analysis, however, the resultant EPDM insulated drop wire, yielded characteristics which placed it above the other constructions in the market. Since its introduction, about 100 million feet have been installed under a myriad of installation and service conditions within the United States.