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This study investigates the potential of using natural cotton stalk (CS) to enhance the properties of poly(lactic acid) (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) composite materials. Simple processed CS, used as a bio‐based filler, is integrated into the PLA/PBAT matrix with the objective of improving mechanical properties, barrier performance, and compatibility, while simultaneously reducing costs and environmental impact. The experiments conducted include tensile testing, scanning electron microscopy analysis, Fourier‐transform infrared spectroscopy (FTIR) analysis, X‐ray diffraction study, thermogravimetric analysis, contact angle measurement, water absorption tests, as well as water vapor and oxygen permeability tests. The results demonstrate that the inclusion of CS significantly enhances the mechanical properties and crystallinity of PLA/PBAT composites, along with increasing their water vapor and oxygen barrier capabilities. Compared to PLA/PBAT without CS, the addition of 2% CS to PLA/PBAT led to substantial improvements in tensile strength and elongation at break, with increases of 21.5%, 41.6%, and 74.4%, respectively. Additionally, scanning electron microscopy and Fourier‐transform infrared spectroscopy analyses indicate that the incorporation of CS promotes the compatibility and chemical interaction between PLA and PBAT, thereby enhancing various properties of the composite material. Image analysis revealed that the distribution area of CS fibers in the polymer matrix increased with content up to a peak at 2% but decreased at higher contents due to severe agglomeration, leading to uneven distribution and performance decline. This work proposes three possible reasons for the improvement in water vapor and oxygen permeability performance. Overall, the analysis suggests that an optimal amount of CS can effectively enhance multiple properties of PLA/PBAT composites, while excessive CS may lead to a decline in performance. Highlights: Cotton stalk (CS) boosts polylactic acid/poly(butylene adipate‐co‐terephthalate) (PLA/PBAT) tensile strength by 21.5% and elongation by 41.6% at 2% inclusion.CS addition enhances water vapor and oxygen barrier properties of PLA/PBAT.Scanning electron microscopy and Fourier‐transform infrared spectroscopy show CS improves PLA/PBAT compatibility and strength.Optimal CS content at 2% identified for best mechanical and barrier performance.Study validates using agricultural waste as fillers in eco‐friendly composites. [ABSTRACT FROM AUTHOR]

To enhance the various properties of polyvinyl alcohol (PVA), varying concentrations of carboxy-functionalized graphene (CFG) were employed in the preparation of CFG/PVA nanocomposite films. FTIR and XRD analyses revealed that CFG, in contrast to graphene, not only possesses carboxylic acid group but also exhibits higher crystallinity. Mechanical testing indicated a notable superiority of CFG addition over graphene, with optimal mechanical properties such as tensile and yield strengths being achieved at a 3% CFG concentration. Relative to pure PVA, the tensile strength and yield strength of the composite increased by 2.07 and 2.01 times, respectively. XRD analysis showed distinct changes in the crystalline structure of PVA with the addition of CFG, highlighting the influence of CFG on the composite structure. FTIR and XPS analyses confirmed the formation of ester bonds between CFG and PVA, enhancing the overall performance of the material. TGA results also demonstrated that the presence of CFG enhanced the thermal stability of CFG/PVA nanocomposite films. However, analyses using scanning electron microscopy and transmission electron microscopy revealed that a 3% concentration of CFG was uniformly dispersed, whereas a 6% concentration of CFG caused aggregation of the nanofiller, leading to a decrease in performance. The incorporation of CFG significantly enhanced the water vapor and oxygen barrier properties of PVA, with the best performance observed at a 3% CFG concentration. Beyond this concentration, barrier properties were diminished owing to CFG aggregation. The study further demonstrated an increase in electrical conductivity and hydrophobicity of the nanocomposites with the addition of CFG. Antibacterial tests against E. coli showed that CFG/PVA nanocomposites exhibited excellent antibacterial properties, especially at higher CFG concentrations. These findings indicate that CFG/PVA nanocomposites, with an optimized CFG concentration, have significant potential for applications requiring enhanced mechanical strength, barrier properties, and antibacterial capabilities. [ABSTRACT FROM AUTHOR]

This research delves into the impact of incorporating thermally treated oyster shell powder (TOS), a biowaste filler, into low-density polyethylene (LDPE) to develop a LDPE/TOS blend, aiming at enhancing food packaging materials. The LDPE/TOS blend portrays advantageous characteristics such as augmented mechanical strength, thermostability, crystallinity, water absorption, and improved hydrophobicity with TOS content up to 50%. Microstructure analysis reveals a transition from a sparse to a more interconnected structure, contributing to the amplified tensile strength. The blend demonstrates increased barrier properties against water vapor transmission, which is attributed to elongated diffusion paths induced by the TOS particles. Application of the blend material in vegetable preservation trials manifested a substantial reduction in water loss compared to pure LDPE or no packaging. This biowaste-based blend film extends the shelf-life of chicken significantly when compared to that of pure LDPE. Importantly, the LDPE/TOS blend exhibits excellent antibacterial properties against both Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Nano zinc oxide-decorated graphene (G-ZnO) was blended with polyphenylene sulfide (PPS) to improve its tensile, thermal, crystalline, and barrier properties. The properties of neat PPS and PPS/G-ZnO nanocomposites were characterized and compared using various tests, including tensile tests, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, evaluation of Escherichia coli inhibition, and barrier performance. The results demonstrated that G-ZnO played a crucial role in heterogeneous nucleation and reinforcement. When the concentration of G-ZnO was 0.3%, the tensile strength, elongation at break, thermostability, crystallinity, and water vapor permeability coefficients (WVPC) approached their maximum values, and the microscopic morphology changed from the original brittle fracture to a relatively tough fracture. In addition, when G-ZnO was added to PPS at a ratio of 0.3%, the tensile strength, elongation at break, and WVPC of PPS were increased by 129%, 150%, and 283%, respectively, compared to pure PPS. G-ZnO endowed the nanocomposites with antibacterial properties. The improvement in barrier performance can be attributed to three reasons: (1) the presence of G-ZnO extended the penetration path of molecules; (2) the coordination and hydrogen bonds between PPS polymer matrix and G-ZnO nanofiller narrowed the H2O transmission path; and (3) due to its more hydrophobic surface, water molecules were less likely to enter the interior of PPS/G-ZnO nanocomposites. This study provides valuable insights for developing high-performance PPS-based nanocomposites for various applications. [ABSTRACT FROM AUTHOR]

In this investigation, purified attapulgite (ATT) and polyvinyl alcohol (PVA) were utilized to fabricate nanocomposite hydrogels and a xerogel, with a focus on studying the impact of minor additions of ATT on the properties of the PVA nanocomposite hydrogels and xerogel. The findings demonstrated that at a concentration of 0.75% ATT, the water content and gel fraction of the PVA nanocomposite hydrogel reached their peak. Conversely, the nanocomposite xerogel with 0.75% ATT reduced its swelling and porosity to the minimum. SEM and EDS analyses revealed that when the ATT concentration was at or below 0.5%, nano-sized ATT could be evenly distributed in the PVA nanocomposite xerogel. However, when the concentration of ATT rose to 0.75% or higher, the ATT began to aggregate, resulting in a decrease in porous structure and the disruption of certain 3D porous continuous structures. The XRD analysis further affirmed that at an ATT concentration of 0.75% or higher, a distinct ATT peak emerged in the PVA nanocomposite xerogel. It was observed that as the content of ATT increased, the concavity and convexity of the xerogel surface, as well as the surface roughness, decreased. The results also confirmed that the ATT was evenly distributed in the PVA, and a combination of hydrogen bonds and ether bonds resulted in a more stable gel structure. The tensile properties exhibited that when compared with pure PVA hydrogel, the maximum tensile strength and elongation at break were achieved at an ATT concentration of 0.5%, indicating increases of 23.0% and 11.8%, respectively. The FTIR analysis results showed that the ATT and PVA could generate an ether bond, further confirming that ATT could enhance the PVA properties. The TGA analysis showed that the thermal degradation temperature peaked when the ATT concentration was at 0.5%, providing further evidence that the compactness of the nanocomposite hydrogel and the dispersion of the nanofiller was superior, contributing to a substantial increase in the mechanical properties of the nanocomposite hydrogel. Finally, the dye adsorption results displayed a significant rise in dye removal efficiency for methylene blue with the increase in the ATT concentration. At an ATT concentration of 1%, the removal efficiency rose by 103% compared with that of the pure PVA xerogel. [ABSTRACT FROM AUTHOR]