Characterization of Extruded Poly(lactic acid)/Pecan Nutshell Biocomposites

Abstract

Pecan nutshells are a solid form of waste obtained from the pecan nut production and they have been explored as an inexpensive filler for incorporation by melt blending into the poly(lactic acid) (PLA) matrix. The pecan nutshells contain polyphenols, proteins, tannins, sugars, and lipids; some of these components must be released in order to improve adhesion with a polymeric matrix. The physicochemical characterization of the extruded biocomposites of pecan nutshell powder (PNSP) at 0, 5, and 7.5% wt. with two treatments (untreated and defatted) into PLA is presented in this work. The incorporation of PNSP into the PLA matrix caused a variation in color and density and increased the water absorption. However, some mechanical and thermal parameters of the biocomposites showed a significant decrease. The morphological analysis showed good dispersion and adhesion of the PNSP to the PLA matrix. Based on the results of the characterization, biocomposites formulated with defatted PNSP have a potential to be used as sustainable fillers in PLA biocomposites. These biocomposites have a potential application as food containers, packaging trays, or disposable items.

Analysis, Development, and Scaling-Up of Poly(lactic acid) (PLA) Biocomposites with Hazelnuts Shell Powder (HSP)

“…The HSPs’ addition increases the crystallinity of the PLA, causing a shift of the cold crystallization temperature towards lower temperatures. HSP seems to act as a nucleating agent, providing heterogeneous nucleation sites similar to other systems filled with natural fibers [ 27 , 47 , 48 ]. In particular, as the HM200 are finer and more homogeneous with a tighter diameter distribution curve, they are more effective in crystallizing the PLA, when compared to their H0210 counterparts.…”

Reuse of Different Agroindustrial Wastes: Pinhão and Pecan Nutshells Incorporated into Biocomposites Using Thermocompression

“…Other researchers stated that pecan nutshells could be a reinforcing filler in polymer-based biocomposites once it presents good dispersion and adhesion to a PLA matrix [31]. Moreover, biocomposites added with pecan nutshells could be applied as food containers, packaging trays, or disposable items [32].…”

Potential applications of pecan residual biomasses: a review

“…Numerous studies have indicate the application of this technique in pecan waste materials, mainly aiming at characterizing the physicochemical composition and obtaining properties that present activity against pathogens of these residues. Studies have shown that the application of this method and methane as a solvent allowed a detailed analysis of the pecan shell composition, characterizing the phenolic compounds, tannins and lipids present in these materials, as well as a morphological evaluation of their structure [53]. In addition, the obtaining of antioxidant materials from pecan shells by the Soxhlet and methane method as a solvent was effective in inhibiting the activity of a range of bacterial microorganisms [54].…”