The effects of supercritical carbon dioxide on the degradation and antimicrobial properties of PLA biocomposite

Biopolymer products that is biodegradable presently attracting an attention from researchers and industry. The biodegradable packaging based on polylactic acid (PLA), durian skin fibre (DSF), epoxidized palm oil (EPO) and incorporated with cinnamon essential oil (CEO) as antimicrobial agent have been developed and showed to be a promising field of research. This paper reported the effects of supercritical carbon dioxide on the degradation and antimicrobial properties of PLA biocomposite films produced via solvent casting. The biocomposites underwent supercritical carbon dioxide (SCCO2) treatment at two different conditions under 40 °C temperature and at 100 bar and 200 bar pressure. Water absorption test showed that the untreated PLA biocomposite absorbed most water as compared to treated PLA biocomposite with SCCO2 at 5.1%. This is due to the hydrophilic nature of the fibre that absorbed water molecules. Soil burial test showed that the treated PLA biocomposite possessed the highest value of weight losses after 80 days with 97.8%. Biocomposite with the presence of CEO demonstrated antimicrobial activity against both gram-positive and gram-negative bacteria. This showed that SCCO2 significantly improved the properties of PLA biocomposite films. The supercritical fluid treatment of PLA biocomposite could be an alternative for active packaging industries to ensure that the packaging product meets the requirement by consumers as well as being an eco-friendly product

Effect of supercritical carbon dioxide on tensile Properties of Durian skin fibre biocomposite

The exploration of new biocomposites that are environmental friendly is gain attention due to depletion of petroleum resources and increasing global environmental concern. Therefore, the investigation of environmental friendly and sustainable materials requires to substitute the synthetic based materials. This project is conducted to investigate the effect of supercritical carbon dioxide on tensile properties of PLA/DSF biocomposite films. The PLA/DSF biocomposites are produced via solvent casting method. Then, the samples are treated under supercritical carbon dioxide (SCCO2) at 40oC and at 200 bar pressure. From tensile properties, it was found that the tensile strength and modulus for untreated and treated PLA/DSF biocomposite are higher compared to net PLA which are 24.9 MPa and 23.5 MPa. Thus, the addition of durian skin fiber improved the mechanical strength PLA polymer. But, the presence of foams and pore in treated PLA/DSF biocomposites decreased its tensile properties by 1.4 MPa less compared to untreated samples as confirmed by morphological observations under scanning electron microscope

Optimization of component in solution casted polylactic acid biocomposite by response surface methodology

The significant value of renewable resources used for food packaging has motivated consumer demand, thereby driving consumers to pay closer attention to biodegradable packaging applications. Polylactic acid (PLA) together with durian skin fibre (DSF), epoxidized palm oil (EPO) and cinnamon essential oil (CEO) have been used to produce thin film via the solution casting method. This research study was conducted to optimise the potential effect of DSF content, EPO content and CEO content by determining the tensile properties of PLA biocomposites. The design of experiments (DOE) via response surface methodology was used to analyse the results. The optimum values for the tensile properties of PLA biocomposite were found at 3 wt% DSF, 5 wt% EPO and 1 wt% of CEO. The optimum tensile strength and tensile modulus of PLA composite were 24.9 MPa and 375.9 MPa, respectively. The DSF content influences the tensile properties of PLA biocomposite, followed by the EPO content and CEO content based on the analysis of variance. The P-value of both responses in the design of experiments is less than 0.05 which verifies that the tensile properties model is significant. The coefficient, R2, for tensile strength is 0.8908, while the coefficient result of the tensile modulus is 0.8916

Tensile properties of durian skin fibre reinforced plasticized polylactic acid biocomposites

This research investigates the effects of plasticizer and durian skin fibre (DSF) loading on tensile and morphological properties of polylactic acid (PLA) biocomposites. Epoxidized palm oil (EPO) was added as a plasticizer in this project. The effect of EPO content 0–10 wt% was investigated over the tensile properties of PLA. EPO at 5 wt% was found to provide the highest tensile properties on PLA biocomposite. The plasticized PLA was then investigated for the effect of DSF content by varying the DSF at 1, 3 and 5 wt%. The tensile properties improved by about 7% with 3 wt% DSF. Scanning electron micrograph revealed that a ductile failure was induced in PLA composite with 5 wt% EPO and 3 wt% DSF

Impregnation of cinnamon essential oil into plasticised polylactic acid biocomposite film for active food packaging

The investigation of environmentally friendly and sustainable food packaging for daily high consumption is necessary to replace existing synthetic packaging. This study reported the efects of antimicrobial agents on the properties of durian skin fbre (DSF)-reinforced plasticised polylactic acid (PLA) biocomposite flms produced via solvent casting. Cinnamon essential oil (CEO) was incorporated into the PLA biocomposite at amounts from 0 to 5 wt%. Thermogravimetric analysis showed the lowest weight loss due to biocomposite degradation after 500 °C in 1 wt% CEO flm. Diferential scanning calorimetry analysis showed that the biocomposites with CEO were less crystalline suggesting that the structure of the biocomposite was less rigid and fexible. CEO improved the barrier properties of the biocomposite by decreasing the water vapour permeability. Biocomposites with CEO also demonstrated antimicrobial activity against both gram-positive and gram-negative bacteria. The plasticised PLA/DSF biocomposite with CEO is transparent, indicating potential as an active food packaging material