Valoriza??o de res?duos lignocelul?sicos da biomassa regional com potencial para obten??o de comp?sitos polim?ricos

• Main Author: Mattos, Adriano Lincoln Albuquerque
• Other Authors: 40405036191
• Language: Portuguese
• Published: PROGRAMA DE P?S-GRADUA??O EM CI?NCIA E ENGENHARIA DE MATERIAIS 2017
• Subjects: CNPQ::ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA; Polipropileno; Comp?sitos; Fibras naturais; Cajueiro; Carna?ba
• Online Access: https://repositorio.ufrn.br/jspui/handle/123456789/23942

Submitted by Automa??o e Estat?stica ([e-mail]) on 2017-09-19T19:40:39Z No. of bitstreams: 1 AdrianoLincolnAlbuquerqueMattos_TESE.pdf: 27478075 bytes, checksum: 07d8b83bd142d721fba0a56eaf59e772 (MD5) === Approved for entry into archive by Arlan Eloi Leite Silva ([e-mail]) on 2017-09-19T22:36:46Z (GMT) No. of bitstreams: 1 AdrianoLincolnAlbuquerqueMattos_TESE.pdf: 27478075 bytes, checksum: 07d8b83bd142d721fba0a56eaf59e772 (MD5) === Made available in DSpace on 2017-09-19T22:36:46Z (GMT). No. of bitstreams: 1 AdrianoLincolnAlbuquerqueMattos_TESE.pdf: 27478075 bytes, checksum: 07d8b83bd142d721fba0a56eaf59e772 (MD5) Previous issue date: 2017-06-28 === As fibras lignocelul?sicas t?m se tornado alternativas econ?micas e ecol?gicas para uso como refor?os ou cargas em comp?sitos com pol?meros virgens ou reciclados. O presente trabalho foi subdividido em tr?s artigos que abordaram diferentes aspectos do desenvolvimento de comp?sitos. O primeiro envolveu a modifica??o de part?culas lignocelul?sicas, utilizando o l?quido da casca da castanha de caju (LCC) como fonte de cardanol, tendo por objetivo o incremento da degradabilidade de comp?sitos de polipropileno (PP) com diferentes tipos de part?culas lignocelul?sicas. Ensaios de termooxida??o e an?lises do comportamento mec?nico, da composi??o qu?mica e das propriedades f?sicas das amostras, permitiram a verifica??o de que os comp?sitos produzidos com part?culas modificadas com o LCC se degradaram na metade do tempo dos comp?sitos convencionais. O segundo artigo objetivou a otimiza??o da metodologia de modifica??o qu?mica da superf?cie de part?culas lignocelul?sicas com LCC, que tamb?m pode ser utilizada como etapa intermedi?ria na funcionaliza??o das part?culas lignocelul?sicas, pois introduz em sua superf?cie s?tios de maior reatividade. A efici?ncia das metodologias de modifica??o qu?mica foi avaliada com o uso de t?cnicas de microscopia eletr?nica de varredura (MEV), espectroscopia de infravermelho por transformada de Fourier (FTIR), termogravimetria (TG) e ?ngulo de contato. Tamb?m foi avaliado o comportamento das part?culas modificadas em comp?sitos com polipropileno. As propriedades dos comp?sitos obtidos foram avaliadas por ensaio de tra??o e an?lise t?rmica din?mico mec?nica (DMTA). O terceiro artigo abordou a produ??o de comp?sitos de PP com farinha de madeira de cajueiro e farinha de folha de carna?ba. As propriedades f?sicas, mec?nicas e morfol?gicas foram avaliadas por TG, calorimetria explorat?ria diferencial (DSC), DMTA, e MEV. Comp?sitos obtidos com fibras in natura, mercerizadas e compatibilizadas com anidrido maleico foram comparados, tendo sido observados os melhores desempenhos nos comp?sitos com o uso do anidrido maleico e farinha da folha de carna?ba. === Lignocellulosic fibers have become an economical and ecological alternative for use as reinforcements and fillers in composites made of virgin or recycled polymers. The present work was subdivided in three papers that focus different aspects of the development of composites. The first one had involved the modification of lignocellulosic particles, using the cashew nut shell liquid (CNSL) as the source of cardanol. The objective was increasing in the degradability of polypropylene (PP) composites made of different types of lignocellulosic particles. Thermo-oxidation tests and analyzes of the mechanical behavior, chemical composition and physical properties of the samples allowed the verification that composites produced with CNSL-modified particles degraded in half the time of the conventional ones. The second article aimed at optimizing the methodology of chemical modification of lignocellulosic particles surface with CNSL that can also be used as an intermediary step in further functionalization of lignocellulosic particles, as it introduces upon its surface higher reactivity sites. The efficiency of the chemical modification methodologies was evaluated with the use of scanning electron microscopy (SEM), infrared spectroscopy (FTIR), thermogravimetry (TGA) and contact angle. The behavior of composites made of the modified particles in polypropylene matrix was also evaluated by mechanical tests and dynamic mechanical thermal analysis (DMTA). The third paper dealt with the production of PP composites made of cashew wood flour and carnauba leaf flour. The physical, mechanical and morphological properties were evaluated by TGA, differential scanning calorimetry, mechanical tensile and flexural tests, and SEM. Composites made of bulk fibers, mercerized and coupled with maleic anhydride were compared and the best performances were observed in the composites using maleic anhydride as coupling agent and carnauba fibers.