COMPORTAMENTO REOLÓGICO DE COMPÓSITOS GEOPOLIMÉRICOS A BASE DE METACAULIM COM A INCORPORAÇÃO DE NANOTUBOS DE CARBONO
Keywords:
geopolímero, metacaulim, nanotubos de carbono, reologia, reometria rotacionalAbstract
Os geopolímeros vem recebendo grande atenção e são considerados potenciais materiais alternativos ao cimento Portland. Entretanto, os estudos que avaliaram as propriedades reológicas de compósitos geopoliméricos com a incorporação de nanotubos de carbono (NTC) ainda são escassos. Diante disso, este estudo teve por objetivo avaliar o comportamento reológico através do ensaio de reometria rotacional de pastas de geopolímero produzidas com dos tipos de metacaulim (MK1 e MK2) e teor de NTC de 0,2% em relação a massa de precursor. Um estudo preliminar mostrou que o modelo de Casson foi o que apresentou o melhor ajuste aos dados reológicos para ambos os tipos de precursores avaliados. Além disso, verificou-se que a incorporação de NTC não afetou significativamente a tensão de escoamento dos compósitos. Em contrapartida, os NTC ocasionaram um aumento de 18,4% na viscosidade da matriz composta pelo MK1.
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