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Polímeros 2012
Comportamento termomecanico de compósitos ativos preparados com nanocompósitos epóxi/argila organofílica e fios de liga Ni-Ti com memória de formaDOI: 10.1590/S0104-14282012005000020 Keywords: epoxy nanocomposite, shape memory alloys, active composites. Abstract: in this work, epoxy/organoclay nanocomposites were selected as matrix for presenting high enough glass transition temperature (tg) and thermal stability values in order to be incorporated in shape memory alloys (sma). four volume fractions of sma wires containing ni-ti (1.55, 2.56, 3.57 and 4.54%) were embedded in diglycidyl ether of bisphenol a (dgeba), cured with the aromatic amine 4,4’-diamino diphenyl sulfone (dds) and containing 1 phr of purified organobentonite (apoc). the formation of nanocomposite was confirmed by x ray diffraction analysis, while the phase transformation of ni-ti wires was determined by dynamic mechanical analysis (dma). samples of the active composites prepared from nanocomposite matrix and ni-ti wires were mainly characterized by dma. a recovery of the storage modulus of the active composite was observed during heating in the range of phase transformation of ni-ti wires when the volume fraction was maintained at around 3.5%.
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