Biocomposite Based on Polylactic Acid and Rice Straw for Food Packaging Products

Plastic containers, commonly produced from non-biodegradable petroleum-based plastics such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), raise significant environmental concerns due to their persistence. The disposal of agricultural waste, specifically rice straw (RS), through burning, further compounds these environmental issues. In response, this study explores the integration of polylactic acid (PLA), a biodegradable material, with RS using a twin-screw extruder and injection process, resulting in the creation of a biodegradable packaging material. The inclusion of RS led to a decrease in the melt flow rate, thermal stability, and tensile strength, while concurrently enhancing the hydrophilic properties of the composite polymers. Additionally, the incorporation of maleic anhydride (MA) contributed to a reduction in the water absorption rate. The optimized formulation underwent migration testing and met the standards for food packaging products. Furthermore, no MA migration was detected from the composite. This approach not only provides a practical solution for the disposal of RS, but also serves as an environmentally-friendly alternative to conventional synthetic plastic waste.

Development of electrospun keratin/coenzyme Q10/poly vinyl alcohol nanofibrous scaffold containing mupirocin as potential dressing for infected wounds

Background

Nanostructured wound dressings produced by electrospinning biocompatible polymers possess great potential because they resemble the natural extracellular matrix and support cell adhesion, proliferation, and differentiation. This study seeks to fabricate mupirocin, keratin, and coenzyme Q10 (Co Q10)-loaded PVA electrospun scaffolds intended for wound healing application and to characterize their morphology, physical properties, antibacterial activity, and biocompatibility. Polyvinyl alcohol (PVA) (10% w/v), various concentrations of keratin/Co Q10 fibrous scaffolds (electrospun at a voltage of 50 kV, flow rate of 4 mL/h), and 2% mupirocin was designed and fabricated to activate keratinocytes in the wound bed, stimulate cell proliferation, and increase antimicrobial penetration.

Results

The diameters of the scaffolds were observed to be in the nanoparticulate range 2.11 ± 0.20 to 3.27 ± 0.10 nm. By 30 min, all the scaffolds had more than 50% of the cumulative concentration of mupirocin released with 51.06 ± 2.104% to 74.66 ± 1.72% of mupirocin released. At 1 h, 80% of the mupirocin in the scaffold was seen to have diffused out of the scaffold. Release of mupirocin was modulated; an initial burst release was followed by sustained release over 2 h. Electrospun keratin/Co Q10/PVA scaffold containing mupirocin showed excellent antimicrobial activity against all the clinical isolates of 2586, Staphylococcus aureus 2590, 2583, 2587, 2555. All the electrospun scaffolds showed higher cell viability values than the control at 48 and 72 h, with the optimized CoQ10 scaffold concentration being 0.05% w/w.

Conclusion

Electrospun nanofibers combining the biocompatibility potential of PVA with the bioactive nature of keratin (0.01% w/w) and CoQ10 (0.5% w/w) and the antibacterial property of mupirocin as a new potential for proper wound care was successfully developed. The cell line studies on this electrospun scaffold (PKCM 3) showed their ability to support the growth of keratinocytes hence the potential of developed scaffolds as a wound dressing. In vivo studies to further investigate the applications of the electrospun keratin/Co Q10/PVA nanofibrous scaffold as a wound dressing is however required.

EPDM-G-GMA Toughening of Straw/Polypropylene Composites: Mechanical Properties, Thermal Stability and Rheological Properties

Natural fiber reinforced polymer composites have the advantages of low density, low cost and renewability. However, the inferior mechanical property restricts the application. In this work, EPDM-g-GMA has been added to straw/PP composites to improve the properties. The mechanical properties, thermal stability, crystallinity and melt viscosity have been invested. The results reveal that the mechanical properties of straw/PP/EPDM composites are improved remarkably and the impact strength more than doubles compared to straw/PP composites. Surface microstructure analysis reveals that the composite has good interfacial compatibility and dispersing performance. The maximum decomposition temperature, the melting enthalpy and crystallinity increased. The glass transition temperature and process ability are also improved by the addition of EPDM.