![]() On the basis of a theoretical prediction that increasing interaction potential between CNTs lowers their critical concentration to form an infinite percolation network, poly(3-(trimethoxysilyl) propyl methacrylate) (PTMSPMA) is used to disperse and functionalize MWCNTs where the subsequent hydrolysis and condensation of PTMSPMA introduces strong and permanent chemical bonding between MWCNTs. The excellent compression recoverable property, hierarchically porous structure with large surface area, and high conductivity grant the MWCNT aerogels exceptional pressure and chemical vapor sensing capabilities.Ībstract = "Ultralight multiwalled carbon nanotube (MWCNT) aerogel is fabricated from a wet gel of well-dispersed pristine MWCNTs. cm -1 by a high-current pulse method without degrading their structures.cm -1 that can be further increased to 0.67 S.The aerogels have an electrical conductivity of 3.2 × 10 -2 S Despite the ultralow density, the MWCNT aerogels have an excellent compression recoverable property as demonstrated by the compression test. The entangled MWCNTs generate mesoporous structures on the honeycomb walls, creating aerogels with a surface area of 580 m 2/g which is much higher than that of pristine MWCNTs (241 m 2/g). The MWCNT aerogel has an ordered macroporous honeycomb structure with straight and parallel voids in 50-150 μm separated by less than 100 nm thick walls. After removing the liquid component from the MWCNT wet gel, the lightest ever free-standing MWCNT aerogel monolith with a density of 4 mg/cm 3 is obtained. The interaction is both experimentally and theoretically proven to facilitate the formation of a MWCNT percolation network, which leads to the gelation of MWCNT dispersion at ultralow MWCNT concentration. Also, the optimum percent of nanotube and silica aerogel in the mix design of concrete are 5% and 4% respectively.Ultralight multiwalled carbon nanotube (MWCNT) aerogel is fabricated from a wet gel of well-dispersed pristine MWCNTs. The results showed that combination use of silica aerogel and nanotube not only improves the compressive strength and durability of concrete but also enhances the performance of thermal conductivity of concrete. Silica aerogel was used in the amounts of 0, 4, 6, 8 percent of concrete and carbon nanotube was used in quantities of 0, 0.03, 0.05. To this end, 16 mix designs of concrete were considered and totally 192 samples were made. This study examined compressive strength, electrical resistivity, and penetration of chloride and thermal conductivity of concrete. The growing interest in this field comes from the desire to modify the cement matrix at the scale of their main compounds, taking advantage of the outstanding properties of CNTs. Carbon nanotubes (CNTs) have been extensively studied as a reinforcement material for cement-based composites. In this study, carbon nanotube was used in order to overcome the undesirable properties of silica aerogel in concrete. Furthermore, despite having a relatively high compressive strength, it is very fragile due to its low tensile strength. However, the implementation of silica aerogel as building insulation is restricted due to high manufacture in cost. Silica aerogels as a nano material have significant properties including high porosity, high specific surface area, excellent heat insulation and low dielectric constant properties, low density and the potential to become an effective building insulation material.
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