Easy, Fast Self-Heating Polyurethane Nanocomposite with the Introduction of Thermally Annealed Carbon Nanotubes Using Near-Infrared Lased Irradiation

Abstract

In this study, high-crystallinity single walled carbon nanotubes (H-SWNTs) were prepared by high-temperature thermal annealing at 1800 °C and a self-heating shape memory polyurethane nanocomposite with excellent self-heating characteristics was developed within a few seconds by irradiation with near-infrared rays. With a simple method (heat treatment), impurities at the surface of H-SWNTs were removed and at the same time the amorphous structure converted into a crystalline structure, improving crystallinity. Therefore, high conductivity (electric, thermal) and interfacial affinity with PU were increased, resulting in improved mechanical, thermal and electric properties. The electrical conductivity of neat polyurethane was enhanced from ~10–11 S/cm to 4.72 × 10−8 S/cm, 1.07 × 10−6 and 4.66 × 10−6 S/cm, while the thermal conductivity was enhanced up to 60% from 0.21 W/mK, 0.265 W/mK and 0.338 W/mK for the composites of 1, 3 and 5 wt%, respectively. Further, to achieve an effective photothermal effect, H-SWNTs were selected as nanofillers to reduce energy loss while increasing light-absorption efficiency. Thereafter, near-infrared rays of 818 nm were directly irradiated onto the nanocomposite film to induce photothermal properties arising from the local surface plasmon resonance effect on the CNT surface. A self-heating shape memory composite material that rapidly heated to 270 °C within 1 min was developed, even when only 3 wt.% of H-SWNTs were added. The results of this study can be used to guide the development of heat-generating coating materials and de-icing materials for the wing and body structures of automobiles or airplanes, depending on the molding method.

Genetic studies in Neolamarckia cadamba (Kadam) tree species

“…Current study was supported by plethora of workers also reported the existence of significant differences and superiority of few seed sources. progenies and provenances in various trees like Azadirachta indica (Syed et al 2013) [14] Populus deltoides (Jha, 2012) [15] Gmelina arborea (Kumar et al, 2005) [16] Eucalyptus tereticornis (Ginwal et al 2004) [17] , Dalbergia sissoo (Tewaric et al, 1996) [18] . Success of the tree improvement program depends on the variability present in material.…”

Failure Analysis of Abnormal Cracking of the Track Circuit Reader Antenna Baffle for High-Speed Trains

“…Due to its high hardness, good strength, high elasticity, wear resistance, tear resistance, and aging resistance [ 1 , 2 ], PUR is widely used [ 3 , 4 , 5 , 6 ]. However, it turns out that like other polymer materials [ 7 ], PUR also has its drawbacks.…”

Development and Optimization of Water-Soluble Double-Walled Carbon Nanotubes by Effective Surface Treatment of Inner Walls

“…Among the diverse carbon-based nanomaterials, carbon nanotubes (CNTs) have attracted significant attention from researchers because of their unique properties, cylindrical structure, and extraordinarily high length-to-diameter ratio compared to all other nanomaterials. , “Nanotubes” are so named for their lengthy hollow structures, made of graphene sheets folded into tubular shapes. CNTs, which can be mainly divided into single-walled carbon nanotubes (SWNTs), double-walled carbon nanotubes (DWNTs), and multiwalled carbon nanotubes (MWNTs), naturally organize themselves into “ropes” bound together by weak van der Waals forces of attraction. , CNTs have exceptional mechanical, thermal, electrical, and optical capabilities; , however, their inability to dissolve in common solvents significantly limits their potential uses. , MWNTs, including DWNTs, have strong intertube van der Waals attraction forces, which, in addition to their inert graphitic character, is the cause of their insolubility in solvents. To solve the insolubility issue of CNTs, covalent sidewall functionalization chemistry and noncovalent techniques that utilize surfactants or polymers to create kinetically stable suspensions have proven to be the most effective ways to date. − The trade-off between covalent and noncovalent techniques, though, is undesirable.…”

“…CNTs, which can be mainly divided into single-walled carbon nanotubes (SWNTs), double-walled carbon nanotubes (DWNTs), and multiwalled carbon nanotubes (MWNTs), naturally organize themselves into "ropes" bound together by weak van der Waals forces of attraction. 3,4 CNTs have exceptional mechanical, thermal, electrical, and optical capabilities; 5,6 however, their inability to dissolve in common solvents significantly limits their potential uses. 7,8 MWNTs, including DWNTs, have strong intertube van der Waals attraction forces, which, in addition to their inert graphitic character, is the cause of their insolubility in solvents.…”

“…2),(9,4),(8,6),(7,5), and(7,6). Conversely, the W-DWNT solution did not produce any PL signal because of the covalent groups acting as energy drains that quench the PL signal or the breaking of the inner-wall structure of the DWNTs owing to the strong chemical functionalization.…”