Lauric acid coated fly ash as a reinforcement in recycled polymer matrix composites

Abstract

Sustainable composites were developed from fly ash (FA) and recycled polypropylene (R) with lauric acid (LA) as the coupling agent. The FA particles were surface-coated with 1, 2, 3, and 5 wt % LA, and the coating on the FA particles was verified by transmission electron microscopy and Fourier transform infrared spectroscopy. R and LA-coated FA particles were melt-mixed in a 1:1 weight ratio to achieve a high-filler-loaded composite. The flexural, impact, nanoindentation, and fracture surface analyses were carried out to examine the properties of the composites. The flexural strength and modulus values increased in the 2 wt % LA-coated FA/R composites by 6 and 50%, respectively, compared to the values of the uncoated FA/R composites, whereas the impact strength increased considerably by 119% in the 1 wt % LA-coated composites. Nanoindentation tests also showed an increase in the mechanical properties in the case of the 1 and 2 wt % LA-coated composites in comparison to the uncoated ones. Fracture surface studies done by scanning electron microscopy revealed improved interfacial interactions between the filler and matrix in the presence of the LA coupling agent. X-ray diffraction (XRD) studies indicated reorientations of the polymer chains in the presence of different concentrations of the LA coupling agent; this resulted into different crystallinities and crystallite sizes. Differential scanning calorimetry showed a significant difference in the crystalline peaks of the composites, and this corroborated well with the XRD observations. LA, thus, significantly influenced the structural properties of the composites, and this, in turn, influenced their mechanical and thermal properties.

Integral approach of sorption coupled with biodegradation for treatment of azo dye using Pseudomonas sp.: batch, toxicity, and artificial neural network

“…The peak at 1416 cm −1 indicated the presence of -OH groups. The peak at 3643 cm −1 was attributed to -OH absorption bands, suggesting the presence of Ca(OH) 2 in treated fly ash (Sengupta et al 2015). In case of immobilized bacterial cells, similar band stretching as the previous two was found which may be indicated that the bacterial cells immobilized on fly ash by physical entrapment.…”

Antibacterial chitosan/silk sericin 3D porous scaffolds as a wound dressing material

“…Furthermore, a composite from fly ash (FA) and recycled polypropylene (R) were developed using LA as a coupling agent. Nanoindentation tests results also demonstrated an increase in the mechanical properties in the case of the 1 and 2 wt % LA-coated composites in comparison to the uncoated counterpart (Sengupta et al 2015).…”

Polyolefins and Polyethylene Terephthalate Package Wastes: Recycling and Use in Composites

“…As with other fillers, FA is surface modified with coupling agents due to weak interfacial bonding between the FA particles and polymer matrix. Green couplings agents, stearic acid [217], lauric acid [218], and palmitic acid [219], were shown to be effective coupling agents in rPP/FA composites. The use of green coupling agents instead of conventional chemicals can improve the sustainability and reduce the cost of rPO/FA composites.…”