Halloysite-Decorated Mechanically Robust Polyurethane Nanocomposite Foams for Acoustic Relevance

Abstract

Noise pollution affects human health and the environment. In this study, halloysite nanoclay (HNC) was employed as a bio-nanofiller with different ratios (1−5 wt %) to improve the thermal, mechanical, and sound absorption capabilities of the flexible polyurethane (FPU) foam. FPU/HNC composites were characterized using X-ray diffraction, Fourier transform infrared, and field emission scanning electron microscopy techniques. In addition, porosity, apparent density, and sol fraction for FPU/HNC composites were investigated. Compared with the unfilled FPU foam, the results of the FPU/HNC 1% sample showed that the density achieved a maximum value of 38.17 Kg/m 3 , while the porosity was reduced to 83.48%. Moreover, the sol fraction reached the highest value of 13.4% for the FPU/HNC 5% sample. Furthermore, thermogravimetric analysis revealed that adding 1 wt % HNC improved thermal stability than the unfilled FPU. Nevertheless, the DSC measurement proved that HNC increased the glass transition temperature (T g ) for the composites' soft segments. Intriguingly, the mechanical measurements exposed that the compressive and tensile strength of the FPU/HNC 1% sample was enhanced to 158.93 and 154.45%; at the same time, the elongation at break dropped to 124.04%. Nevertheless, the sound absorption measurements (20 mm thickness) showed a slight shift to the mid-frequency range (315−1600 Hz) for FPU/HNC composites than the unfilled FPU.

Co-Influence of Nanofiller Content and 3D Printing Parameters on Mechanical Properties of Thermoplastic Polyurethane (TPU)/Halloysite Nanotube (HNT) Nanocomposites

“…Furthermore, the absorption band at 3292 cm −1 corresponds to the NH bond stretching of TPU [ 59 ], while the peak detected at 2910 cm −1 is associated with its –CH 2 stretching [ 60 ]. The band obtained at 1704 cm −1 is assigned to hydrogen bonds between the N–H and C=O groups in the hard segments and the ester groups for urethane linkage in the soft segments [ 61 ].…”

“…The band obtained at 1704 cm −1 is assigned to hydrogen bonds between the N–H and C=O groups in the hard segments and the ester groups for urethane linkage in the soft segments [ 61 ]. The other characteristic bands at 1510, 1216 and 1057 cm −1 can be attributed to N-H bending vibration, C–O stretching vibration and ester C–O–C symmetric stretching vibration respectively [ 59 ]. Even though TN13 and TN17 have different filler levels (i.e., 8 and 10 wt% HNTs), and were printed using different 3D printing settings (i.e., nozzle temperature, print speed, infill density and layer height), the FTIR spectra of both samples are very similar.…”

“…On the other hand, related bands at 998 and 523 cm −1 arise fro the stretching vibration of O-Si-O, as well as the deformation vibration of Al-O-Si [57,5 Finally, it appears that the FTIR peaks assigned to 909 and 457 cm −1 are due to the defo mation vibration of inner hydroxyl groups. Furthermore, the absorption band at 3292 cm −1 corresponds to the NH bond stretc ing of TPU [59], while the peak detected at 2910 cm −1 is associated with its -CH2 stretchi [60]. The band obtained at 1704 cm −1 is assigned to hydrogen bonds between the N-H a C=O groups in the hard segments and the ester groups for urethane linkage in the s segments [61].…”

“…It can be observed that the maximum degradati was detected on the basis of four degradation peaks in the derivative thermogravimet (DTG) spectra, which are represented by four decomposition temperatures, namely, Td1, T Td3 and Td4 respectively in Table 5. Furthermore, the absorption band at 3292 cm −1 corresponds to the NH bond stretching of TPU [59], while the peak detected at 2910 cm −1 is associated with its -CH 2 stretching [60]. The band obtained at 1704 cm −1 is assigned to hydrogen bonds between the N-H and C=O groups in the hard segments and the ester groups for urethane linkage in the soft segments [61].…”

An integrated experimental and theoretical approach to probe Cr(vi) uptake using decorated halloysite nanotubes for efficient water treatment

“…[40][41][42][43][44][45] Many sponges and synthetic materials like polyurethane and HNTs-polyurethane nanocomposites have been reported. 46 Likewise; various organic, inorganic adsorption materials and their hybrids, hollow spheres, hollow microtubes, magnetic CNTs and nanocomposites have been fabricated for wastewater treatment. [47][48][49][50][51] Among them, some have greater adsorption capacity for cationic and anionic dyes, while others have a high adsorption capacity for heavy metal ions.…”