In this study, a new plastic film with antiviral and antibacterial properties was developed using modified cassava starch with glycidyltrimethylammonium chloride (GTMAC) and reinforced by crystalline nanocellulose (CNC), called Q-CS/CNC. For comparison, a control film (Q-CS) was produced without the addition of CNC. Elemental analysis revealed a degree of substitution (DS) of 0.552, indicating the replacement of the OH groups of starch by the NR₄⁺ groups of GTMAC during the quaternization reaction. The addition of CNC resulted in significant increases (p < 0.05) of 38.9, 38.2, and 43.1% in thickness, opacity, and water vapor permeability measurements, respectively, compared to Q-CS. Incorporating CNC also contributed to an increase of 43.6% in tensile strength and 109% in stiffness but slightly decreased thermal stability. The Q-CS/CNC film demonstrated efficacy by inactivating 99% of the coronavirus in 1 min and inhibiting the growth of Staphylococcus aureus and Escherichia coli. This action is attributed to the electrostatic interaction of quaternary amino groups, grafted onto starch, with the phospholipid membrane of microorganisms, resulting in the inactivation of these microorganisms. Therefore, these results highlight the potential use of Q-CS/CNC film as antimicrobial packaging, especially against coronavirus.

Biocomposites have recently received more attention because of raising environmental awareness and the drive toward sustainable technologies. The most common biodegradable polymer is poly(lactic acid) (PLA), which has an excellent balance of physical and rheological properties, but there is some limit to its usage. PLA properties can be improved by adding different types of fibers or fillers that come from agricultural waste. In this study, corn cob and lavender stem were used to reinforce PLA without any coupling agent, and the properties of the composites were investigated. The melt flow rate (MFR) values decreased with the corn cob content and increased with the addition of lavender stem. Mechanical tests showed that the tensile and flexural modulus of the composites increased and the strengths decreased with the reinforcement material content. The rigidness of PLA slightly decreased with the addition of fillers. There was no significant effect on the thermal properties. The unremarkable improvement of the reinforcement was due to the lack of appropriate adhesion of the two phases. The structure of the compounds was found to be homogenous on the scanning electron microscopy (SEM) micrographs. The incorporation of corn cob and lavender stem can reduce the production cost of materials.

The study investigates a ternary biopolymer blend composed of biopolymers polylactic acid (PLA), polyhydroxybutyrate- co-valerate (PHBV), and lignin extracted from patchouli fiber waste for sustainable packaging applications. A PLA: PHBV blend (70:30) was enhanced by incorporating hydrophobic lignin as a filler in varying loadings of 0, 3, 6, 9, and 12 wt%. The ternary blend was prepared using twin-screw extrusion process, pelletized, and compression-molded into specimens. Comprehensive characterization of the ternary blend included evaluations of water barrier, mechanical, functional, thermal, and morphological properties. Results demonstrated that lignin addition notably improved the compatibility between PLA and PHBV, leading to enhanced barrier performance, mechanical strength, and thermal stability. SEM morphology confirmed improved interfacial adhesion due to hydrophobic nature of lignin, which facilitated better dispersion at lower filler loadings. However, at 12 wt% lignin, property reductions were observed, attributed to lignin agglomeration and poor dispersion. Optimal performance was achieved at 9 wt% lignin loading, offering a balance of improved properties without compromising processability or structural integrity. This study highlights the potential of the PLA/PHBV/lignin ternary blend as a viable, eco-friendly material for sustainable packaging, showcasing improved functionality and environmental compatibility compared to conventional polymers.

This study demonstrated, for the first time, the successful formation of porous paramylon esters, which were made from euglenoid polysaccharide known as paramylon and short-chain fatty acids, through supercritical CO₂ processing. By maintaining a constant ester functional group attached to the paramylon and varying its proportion, distinct porous structures were selectively produced. Solubility parameter estimations indicated that changes in esterification had no significant effect on the solubility of the paramylon esters used in the experiment. Thus, these structural differences are likely attributed to variations in the viscoelastic properties of paramylon esters under supercritical CO₂ conditions. Furthermore, thermal conductivity measurements revealed reductions of up to 20%. Intriguingly, substantial decreases in thermal conductivity were observed even at low foaming ratios, achieved through precise control of the porous structure.

Three-dimensional (3D) bioprinting is a technique currently used for creating tissue engineering scaffolds, using bioinks as the building blocks. These bioinks are composed of biomaterials that provide structural integrity and are synthesized from organic polymers to enhance biocompatibility with the printed constructs. In this study, a series of eleven chitosan-based bioinks were synthesized using the sol-gel technique, employing chitosan of low and medium molecular weight. Three bioink formulations were selected based on their viscosity characteristics and further enriched with gelatin and hydroxyapatite (HA) to enhance their mechanical properties. Characterization tests included Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and rheological assessments. Viscoelastic materials were obtained, and an experimental model was developed to optimize printing parameters, focusing on pressure and printing speed. Our findings indicate that a bioink formulation comprising a blend of medium and high molecular weight chitosan, supplemented with gelatin and hydroxyapatite, was found to be a promising approach for fabricating scaffolds for bone tissue repair.