Regeneration of Spent Bleaching Earth for PLA Nanocomposite Filler

Abstract

This paper concerns on regeneration of spent bleaching earth (SBE) as a filler in biodegradable nanocomposite. The nanocomposite were produced from two different production methods, solvent casting and extrusion. SBE can be used as filler after being regenerated by removing oil and impurities. A regeneration method for SBE was conducted using chemical treatment. Regeneration process was proved to be succesful as shown in FTIR with the absence of peak at 2850 cm—1 – 2930 cm−1 and 1730 cm−1 indicating the disappearance of free fatty acids and ester bonds from regenerated bleaching earth (RBE). The RBE was then applied as filler for PLA-Nanocomposite, biodegradable plastic, a suitable substitute for conventional plastic. The production of nanocomposite used two different surfactants, namely octadecyl amine (ODA) and trimethyl stearyl ammonium chloride (TSC) at two different concentration (20 mmol and 40 mmol). The mechanical property of PLA-Bentonite nanocomposite was then analyzed for tensile strength and permeability. The highest tensile strength and lowest gas permeability was obtained by nanocomposite that used 40 mmol TSC as surfactant, with 12.48 MPa and 0.017 g/day, respectively. Moreover, addition of regenerated bleaching earth to PLA-Nanocomposite during production using extrusion and solvent casting had slight different effect. XRD pattern of all extruded PLA-nanocomposite samples indicated the formation of exfoliated structure, as shown in XRD pattern with very low intensity peak around 2 nm at 2? = 5, while only a few of samples of PLA-nanocomposite created by solvent casting indicating the same structure.

Biocompatible organic coating fabrication via polymer/clay nanocomposites: Evaluation of mechanical improvements

“…In our previous study, the exfoliation of silicate layers was attributed to the similar hydrophilic characteristic of nanocomposite constituents, which is confirmed by FTIR analysis. 16 Scheme 2 represents the hydrogen bond formation between the silicate layers and PVP chains, leading to exfoliation.…”

“…14 In the case of BNT biocomposite films, there are several studies in the literature. [15][16][17][18][19] In the study of Zakaria et al, 15 20 wt% BNT addition in thermoplastic potato starch increased tensile strength by more than 100%. In the study of Sultan et al 19 Sodium alginate/bentonite clay nanocomposites were prepared by solution casting method, revealing both electrical and partly mechanical properties improvement by BNT addition.…”

“…In the case of BNT biocomposite films, there are several studies in the literature 15–19 . In the study of Zakaria et al, 15 20 wt% BNT addition in thermoplastic potato starch increased tensile strength by more than 100%.…”

“…Tensile testing improved elongation at break value, while the tensile strength was reduced by BNT addition. The study of Gultom et al 16 shows that the tensile mechanical properties of polylactic acid (PLA) could be drastically improved by BNT reinforcement. The study also revealed the importance of surfactants as the organic modification improved the tensile strength/elastic modulus of PLA from 1.59 MPa/82.21 MPa to 7.87 MPa/329.72 MPa for unmodified and modified BNT reinforcement, respectively.…”