Enzymatic degradation of coconut shell powder–reinforced polylactic acid biocomposites

Abstract

This work examined the effects of filler content and chemical treatment on the biodegradation of poly(lactic acid) (PLA)/coconut shell (CS) biocomposites in a diastase enzyme-containing buffer medium. CS was treated with two distinct chemical treatments: maleic acid and silanation with 3-aminopropyltriethoxysilane (3-APE). The CS was incorporated into PLA composites and their biodegradation patterns were studied. Both of the treated PLA/CS biocomposites exhibited lower biodegradation rates than the untreated biocomposites due to their enhanced interfacial adhesion, which reduced the area exposed to enzyme hydrolysis. Scanning electron micrographs taken after 30 days of biodegradation displayed surface roughening on both of the treated biocomposites, with fewer voids compared to the untreated biocomposites. The differential scanning calorimetry indicated that the glass transition temperature and melting temperature values of the treated biocomposites increased but that crystallinity declined. The crystallization temperature peak apparently disappeared due to the polymer chain alignment and rearrangement of the shorter PLA chains caused by the degradation. Fourier transform infrared analysis revealed the structural changes in the biocomposites after biodegradation, indicating the presence of soluble lactic acid as was confirmed by ultraviolet–visible spectroscopy analysis.

Advances in Bioresorbable Triboelectric Nanogenerators

“…Although biodegradable polymers can experience various forms of degradation, such as photodegradation, thermal degradation, and mechanical degradation, from a molecular perspective, the chemical biodegradation mechanisms of bioresorbable materials can be categorized into hydrolytic, 175,228,295 oxidative, 176,289 and enzymatic degradation 57,172 (Figure 8). The majority of bioresorbable polymers have functional groups and bonds that readily react with water molecules in physiological conditions, leading to hydrolysis.…”

“…This is achieved by choosing or modifying the constituent materials, ultimately paving the way for their practical applications in the biomedical field. 172,174,175,177,228,230 Despite the noticeable accomplishments, bioresorbable implants with passive operation have inherent limitations regarding stable performance, noninvasive lifetime adjustment, and biosafe device removal due to gradually degrading characteristics. Recent advancements in the understanding of biodegradation processes, together with an increasing demand for novel material platforms, have inspired additional research on active operation to overcome the limitations of conventional bioresorbable implants.…”

“…The enzymatic degradation in bioresorbable implants is triggered by enzymes present in the extracellular matrix and body fluids . Several kinds of enzymes, including lipases, dehydrogenases, proteinases, diastases, and α/β-amylases, can participate in this enzymatic degradation under physiological conditions. − This degradation is influenced by several factors, including enzyme diffusion, reaction kinetics, and the diffusion of decomposition byproducts.…”

A comprehensive review of coconut shell powder composites: Preparation, processing, and characterization

“…PLA-natural fiber biocomposites have been produced to reduce the cost of PLA processing materials through the inclusion of low-cost fibers and also to improve structural strength and moduli due to the reinforcing effect of natural fiber. 49 Since, the composite industry is growing continuously, introducing the benefit of natural fibers in developing materials helps in controlling environmental pollution, while also producing high performance products. In line with this, the possibility to recycle thermoplastics is quite interesting to investigate.…”

Mechanical Properties and Biodegradability of Polylactic Acid/Acrylonitrile Butadiene Styrene with Cellulose Particle Isolated from Nypa Fruticans Husk

“…It contributes to the higher polarity character in the filler filled PLA/ABS biocomposites. Therefore, PLA/ABS/IC biocomposites possessed the highest weight loss percentage since IC contained a higher number of hydroxyl group compared to NFH [28]. Besides that, alkaline fibre treatment employed in the isolation of cellulose had removed waxy substances in NFH and increased IC filler surface accessibility.…”