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 is an editorial article. It has no abstract.

Cross-linking frequently enhanced the mechanical properties of linear polymeric materials; however, it also resulted in the transition from thermoplastic to thermosetting materials, which posed issues from an environmental perspective. Thermoplastic polyurethane (TPU) elastomers were extensively applied across various industries. To improve the mechanical properties of TPU while preserving its environmental benefits, this study integrated radical copolymerization technology to develop a reversible crosslinked TPU. Specifically, the linear polyurethane molecular chains were crosslinked using diallyl disulfide (DADS) as a functional cross-linking monomer. Through radical copolymerization reactions, reversible crosslinks formed from disulfide bonds were created between the linear polyurethane molecular chains, yielding a self-healing reversible crosslinked thermoplastic polyurethane (DSTPU). The study showed that DSTPU could self-heal and dissolve under UV light and alkaline N,N-dimethylformamide (DMF) conditions, achieving 82.2% self-healing efficiency at 3 phr DADS. It dissolved into fine particles in alkaline DMF. Disulfide bonds in DSTPU enhanced cross-linking, boosting 19% oxygen permeability, thermal conductivity (0.218 W/(m·K)), and mechanical properties like tensile stress (11.18 MPa), force (134.13 N), and elongation (548%). These bonds also enhanced aging resistance, cutting ΔYI to 6.0%.

The degradation of different flexible polyurethane foams for molded application after thermal aging were compared. A reference sample using traditional higher emission additives and four samples of different composition using low-emission additives were compared. For the modified samples volatile organic compound (VOC) and semi-volatile organic compound (FOG/SVOC) contents fell well below the benchmarking limits, which indicates that the selected low-emission additives are incorporated into the polymer chain. To examine different material properties and for evaluating changes due to increased temperature exposure for a prolonged period of time mechanical and acoustic tests were carried out before and after dry heat aging. It was found that two low emission samples exhibited superior sound absorption compared to the reference sample along with less significant change after aging in the acoustic properties. The compressive strength was lower than the reference as a result of lower product densities. However, the change in compressive strength after aging was less than 15% (with one exception), which is acceptable according to the standard requirements. Thermogravimetric analysis was also performed and revealed that no significant difference can be observed between the examined samples due to heat degradation, indicating that the modifications made to reduce VOC content did not adversely affect the foam’s resistance to thermal degradation.

The paper deals with the influence of the brittleness of glass fibers on the selected performance properties of the fibrous polymer composite. Understanding the fatigue behavior of fiber-reinforced plastics is desirable for exploiting their features in safe, durable, and reliable industrial components. Based on the proposed methodology, it is possible to assess the impact of material reuse on selected mechanical and rheological properties. To verify the methodology by experimental analysis, homopolymer PP reinforced with chemically grafted glass fiber (30 wt%) was selected. The proposed methodology was subsequently verified by experimental analysis and evaluated statistically. The morphology of the fracture surfaces was evaluated, and the fiber-polymer matrix adhesion was monitored at the interface of the fracture surfaces. Based on the measured and evaluated values and fracture surfaces, we can say that the brittleness of the fibers significantly affects the performance properties of the tested polymer composite.