Search Results (160)

Cellulose nanofiber (CNF) has attracted increasing attention as a sustainable nanomaterial for high-performance films due to its renewability and outstanding mechanical properties. However, the practical applications of CNF films are largely hindered by their insufficient tensile flexibility and gas barrier performance. In the present work, a reinforced, multifunctional nanocomposite film was prepared via the solution casting method by incorporating CNF with poly(butylene adipate-co-terephthalate) (PBAT). The influence of PBAT loading on the mechanical flexibility and barrier performance of the nanocomposite film was investigated, and the interfacial bonding characteristics were also studied. As a result, the composite film containing 40 wt% PBAT (denoted as CNF-PBAT40) exhibited a tensile strength of 49.6 MPa, which is generally seven times higher than that of the pristine CNF film. Moreover, its flexibility was notably enhanced, reaching an elongation at break of 7.8%. Additionally, the CNF-PBAT40 composite film showed a markedly reduced air permeability of 2.6 μm·Pa⁻¹·s⁻¹, compared with 9.5 μm·Pa⁻¹·s⁻¹ for the pristine CNF film. Therefore, these synergistically enhanced properties render CNF-PBAT composite films promising candidates for advanced applications in next-generation sustainable packaging. Full article

Low-density polyethylene (LDPE) and poly (butylene adipate-co-terephthalate) (PBAT) agricultural films are major components of microplastics (MPs) and their contamination in agriculture due to their difficulty to recycle. However, potential degradation mechanisms of MPs from LDPE and PBAT in agricultural soils are still unclear. Here, we isolated a strain of Bacillus cereus L6 from long-term agricultural MP-contaminated soil and analyzed its potential biochemical pathways involved in LDPE and PBAT turnover through functional prediction from shotgun genome sequencing. After 28 days of incubation with MPs, Bacillus cereus L6 caused a net mass loss of 0.99% LDPE-MPs/28 days and 3.58% PBAT-MPs/28 days. The surfaces of LDPE and PBAT degraded in bioassays added with Bacillus cereus L6 showed wrinkles, cracks, and pits, accompanied by an increase in roughness. The crystallinity and thermal stability of both LDPE- and PBAT-MPs were decreased and the hydrophobicity of PBAT-MPs was reduced. Whole-genome sequencing analysis showed that Bacillus cereus L6 potentially encoded genes for enzymes related to the biodeterioration of additives in LDPE and PBAT. Moreover, genomic CAZymes predictive analysis showed that genes related to oxygenases and lyases were annotated in the strain L6 Auxiliary Activities family. These findings offer a theoretical foundation for deeper exploration into the degradation and metabolic processes of MPs from discarded agricultural plastics in the environment. Full article

With the growing demand for eco-friendly food packaging, poly(butylene adipate-co-terephthalate) (PBAT)/polylactic acid (PLA) composite films have emerged as promising biodegradable alternatives, but their inherent limitations (e.g., poor antioxidant capacity, weak UV stability, and insufficient antimicrobial activity) hinder practical applications. This study aimed to address these drawbacks by incorporating Rosmarinus officinalis L. extract (RM) as a natural multifunctional additive. PBAT/PLA/RM blend films with RM concentrations of 0.1%, 0.3%, 0.5%, and 1% were fabricated via melt extrusion and blown film processing. Key characterizations were conducted to evaluate thermal stability, mechanical properties, morphology, antioxidant activity, UV-shielding performance, antimicrobial efficacy, and biodegradability. The results showed that RM significantly enhanced the antioxidant capacity of the films, with the highest DPPH radical scavenging activity achieved at 0.3% RM. UV-blocking performance improved incrementally with increasing RM concentration, and films containing ≥0.5% RM filtered over 90% of UVA and UVB radiation. All composite films met biodegradability standards, with over 90% degradation observed after 240 days of composting, though RM prolonged the initial degradation stage by inhibiting early microbial activity. However, the antimicrobial effect of RM was limited, and concentrations exceeding 1% caused film stickiness, impeding processing. This work demonstrates that RM is a viable natural additive for functionalizing PBAT/PLA films, offering enhanced antioxidant and UV-shielding properties while maintaining biodegradability, thus providing a promising solution for sustainable food packaging. Full article

The environmental behavior of biodegradable plastics under long-term hydrodynamic aging processes in seawater remains poorly understood, although plastic pollution has attracted global concern. This study obtained poly(butylene adipate-co-terephthalate) (PBAT) and poly(butylene succinate) (PBS) microplastics that endured 36-month hydrodynamic aging in seawater to elucidate their physicochemical transformations and interactions with benzo(a)pyrene (BaP). Hydrodynamic aging markedly altered surface morphology, generated cracks and pores, and enriched -C=O and -OH groups, indicating oxidative degradation. Adsorption experiments showed that BaP adsorption capacity of virgin PBAT/PBS reached 213.3/235.3 μg g⁻¹, while it increased to 233.3/258.2 μg g⁻¹ after hydrodynamic aging in seawater. Elevated salinity and alkaline conditions reduced BaP adsorption on microplastics. Notably, hydrodynamic aging mitigated the risk of BaP desorption from PBAT in ectothermic organisms. Gibbs free energy calculations indicated that the adsorption process was primarily driven by hydrophobic effects, hydrogen bonding, and van der Waals forces. These findings highlight that long-term hydrodynamic aging substantially modifies the interfacial properties of biodegradable plastics to alter their capacity for mediating the environmental fate of hydrophobic organic pollutants in marine ecosystems. Full article

In this study, poly(butylene adipate-co-terephthalate) (PBAT), starch, glycerol, and grape seed extract (GSE) were blended and extruded to fabricate PBAT/thermoplastic starch(TPS)/GSE active films by blow molding. The interaction between GSE and TPS primarily occurred through hydrogen bonding, with little interaction observed with PBAT. The oxygen barrier property of the film was improved by the incorporation of GSE into the films, whereas the mechanical properties slightly decreased. The PBAT/TPS/GSE films had excellent UV blocking properties imparted by PBAT and visible light blocking properties endowed by GSE. The films containing GSE offered antimicrobial activity against Escherichia coli and Staphylococcus aureus by delaying bacterial growth. Also, the GSE-added films exhibited antioxidant activity with strong dose dependence due to the free radical scavenging ability of polyphenolic compounds in GSE. The shelf life of peanut butter packaged with the PBAT/TPS/GSE-5 film was expected to exceed 300 days, which was approximately twice that of LDPE film packaging. The proposed active films had good material properties, functional activities, and excellent ability to prolong the shelf life of peanut butter. Full article

Disposable diapers contribute significantly to municipal solid waste, with non-biodegradable polymers such as low-density polyethylene (LDPE) persisting in landfills for centuries. Biodegradable alternatives, including polylactic acid (PLA), poly(butylene adipate-co-terephthalate) (PBAT), bamboo, and organic cotton, offer reduced environmental persistence, although challenges remain regarding cost, mechanical performance, and scalability. This review synthesizes current literature on these materials, highlighting their properties, biodegradation mechanisms, environmental performance, and commercial feasibility. In addition, we examine emerging biodegradable superabsorbent polymers (SAPs), such as polysaccharide-based hydrogels, chitosan, and nanocellulose, essential for fully compostable diapers. Our review uniquely integrates material performance, tropical high-humidity degradation, cost considerations, and consumer acceptance, providing insights into both technological advances and barriers to adoption. Key challenges include high production costs, supply chain limitations, and maintaining performance parity with conventional diapers. Finally, we discuss sustainable waste management strategies, including industrial composting, and identify future research directions focused on optimizing biopolymer properties, safety, and life-cycle impacts. This synthesis informs researchers, industry stakeholders, and policymakers seeking to advance environmentally responsible diaper products. Full article

The widespread use of single-use plastics, particularly polyethylene (PE) and polypropylene (PP), has resulted in severe environmental pollution due to their durability and resistance to degradation. This report reviews current degradable alternatives to conventional polyolefins and strategies for enhancing their breakdown in natural and managed environments. Mechanisms of abiotic and biotic degradation are examined alongside the influence of environmental factors and standardized testing protocols. Commercially available biodegradable polymers—such as polylactic acid (PLA), polyhydroxyalkanoates (PHAs), poly(butylene succinate) (PBS), poly(butylene adipate-co-terephthalate) (PBAT), starch-based plastics, cellulose derivatives, chitosan, and protein-based materials—are evaluated for their sources, degradation behavior, applications, scalability, and limitations. In addition, modification techniques for PE and PP, including copolymerization, pro-degradant additives, blending with biodegradable fillers, surface functionalization, enzyme-assisted degradation, and photocatalytic additives, are critically assessed for their potential to reduce environmental persistence. Key challenges such as performance trade-offs, incomplete degradation, ecotoxicity, cost, scalability, and end-of-life management are discussed within the context of circular economic integration. This report concludes with future research directions aimed at developing cost-effective, high-performance materials that degrade completely under real-world conditions while minimizing ecological impacts. Full article

In this work, polylactic acid (PLA)/poly(butylene adipate-coterephthalate) (PBAT) composites containing nanomagnetite particles were developed for electromagnetic shielding. The nanomagnetite particles acted not only as a conductive filler but also as a reinforced agent and compatibilizer for PLA/PBAT blends. The effect of surface treatments by the silicon coupling agent (SCA) under different pH conditions and with other substances (silica and dopamine (DA)) were investigated in particular. The composites were prepared by thermal mixing and characterized by Fourier-transform infrared spectroscopy (FTRI), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transparency electron microscopy (TEM) and tensile testing. The results show that the interface between the PBAT spheres and the PLA matrix was improved after the addition of magnetite particles treated with SCA or PDA. It is interesting to find that under acidic conditions, SCA acted more efficiently due to the chemical reaction of SCA with the hydroxyl groups on the surface of the magnetite particles, which resulted in chemical improvement. Tensile strength increased about 20%, while elongation also increased about 15%. The fracture surface under SEM clearly showed plastic deformation, which contributed to an improvement in mechanical properties, especially toughness. Full article

The lignin nanoparticle (LNP) was prepared by the self-assembly method and further blended with poly(butylene adipate-co-terephthalate) (PBAT) to obtain a PBAT/LNP composite using a solvent casting method. It was found that the nano-modification of lignin effectively improved the compatibility between the components, and the mechanical properties, gas barrier properties, UV resistance, degradation, and antibacterial properties of the PBAT/LNP composite. Compared with PBAT, the tensile strength, elongation at break, and elastic modulus of the PBAT/LNP composite with 8 wt% LNP (PBAT/LNP-8) increased by 37.36%, 47.30% and 50.70%, respectively. Moreover, the mechanical properties, UV-blocking performance, and gas barrier properties of PBAT/LNP-8 were better than those of the commercial degradable packing bag, and the composite derived from PBAT and lignin extracted from wheat straw also showed excellent properties. This work explored a way to expand the utilization of lignin from lignocellulosic biomass, which not only helped to solve the environmental pollution caused by the widespread use of non-degradable plastics, but also promoted the replacement of fossil resources. Full article

Poly(butylene adipate-co-terephthalate) (PBAT) wastewater, characterized by high chemical oxygen demand (COD) and acidity, poses significant challenges to anaerobic digestion (AD) due to toxicity and volatile fatty acids (VFAs) accumulation. This study coupled granular activated carbon (GAC) and waste iron scraps (WISs) to synergistically enhance AD performance. Batch experiments demonstrated that, compared with the control, the GAC/WISs group achieved a COD removal efficiency of 53.18% and a methane production of 207.53 ± 5.80 mL/g COD, which were 5.48- and 12.14-fold increases, respectively, while reducing the accumulation of total VFAs by 98.48% (to 15.09 mg/L). Mechanistic analysis revealed that GAC adsorbed inhibitors and enriched methanogens, while WISs buffered pH and promoted direct interspecies electron transfer (DIET) through hydrogenotrophic methanogenesis. Metagenomic sequencing showed shifts in microbial communities, with enrichment of syntrophic bacteria (Syntrophobacter) and functional genes (pta, bcd, and pccA), indicating metabolic reprogramming. This study provided a theoretical foundation and engineering strategy for the anaerobic treatment of PBAT wastewater. Full article

Biodegradable polymers offer a promising solution to the growing issue of global microplastic pollution. To effectively replace conventional plastics, it is essential to develop strategies for tuning the properties of biodegradable polymers without relying on additives. Biaxial stretching promotes anisotropic crystallization in polymer domains, thereby altering the mechanical performance of polymer blends. In this study, we employed a design of experiment (DoE) approach to investigate the effects of biaxial stretching at three drawing temperatures (T_ds) and draw ratios (λs) on a biodegradable blend of poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT), aiming to optimize both the strength and ductility. The DoE analysis revealed that the composition, the λ, the interaction between the λ and composition, and the interaction between the T_d and composition significantly affect the elongation at break (ε_Break). For the stress at break (σ_Break), the most influential factors were the interaction between the λ and PLA concentration; a three-way interaction among the λ, PLA, and T_d; the T_d; the λ; and finally the PLA concentration alone. The optimal ε_Break and σ_Break were achieved at a λ = 5 × 5 and T_d = 110 °C, with a composition of 10% PLA and 90% PBAT. The stretched samples exhibited higher crystallinity compared to the pressed samples across all compositions. This work demonstrates that in addition to the composition, the processing parameters, such as the λ and T_d, critically influence the mechanical properties, enabling performance enhancements without the need for compatibilizers or toxic additives. Full article

The incomplete degradation of degradable plastics may pose potential ecological risks, as it can generate degradable microplastics (DMPs), especially when these DMPs coexist with heavy metals in soil. Taking petrochemical-based poly(butylene adipate-co-terephthalate) (PBAT) and bio-based polylactic acid (PLA) as representative DMPs, this study investigated how DMPs affect the adsorption–desorption behavior of Cu²⁺ in soil and the underlying mechanisms via batch equilibrium experiments and characterization analyses. The experiments revealed that ion exchange (accounting for 33.6–34.3%), oxygen-containing functional group complexation, and electrostatic interactions were the primary adsorption driving forces, with chemical adsorption playing the main role. Compared to the soil, the PBAT and PLA had smaller specific surface areas and pore volumes, fewer oxygen-containing functional groups, and especially lacked O-metal functional groups. They can dilute soil, clog its pores, and cover its active sites. 1% DMPs significantly reduced the soil’s equilibrium adsorption capacity (Q_e) (3.7–4.7%) and increased equilibrium desorption capacity (Q_De) (1.7–2.6%), thereby increasing the mobility and ecological risk of Cu²⁺. PBAT and PLA had no significant difference in effects on the adsorption, but their specific mechanisms were somewhat distinct. Faced with the prevalent, worsening coexistence of DMPs and heavy metals in soil, these findings contribute to the ecological risk assessment of DMPs. Full article

Poly(butylene adipate-co-terephthalate) (PBAT) possesses mechanical properties and processing advantages comparable to low-density polyethylene (LDPE). However, its poor water vapor barrier properties (~2 orders of magnitude lower than LDPE) limit its applications in agricultural films and packaging. In this study, dodecenyl succinic anhydride (DDSA) was employed as a functional comonomer to synthesize DDSA-modified PBAT-based copolyesters (PBADT) with varying compositions via co-esterification and melt polycondensation, and the effects of the hydrophobic alkylene side chain on surface hydrophobicity, water vapor barrier property, and other physical and mechanical properties of PBADT were systematically investigated. Results indicate that the introduction of DDSA significantly enhanced the surface hydrophobicity and water vapor barrier properties of PBAT. As the DDSA content increased from 0 to 55 mol%, the water contact angle increased from 79° to 101°, and the water vapor barrier performance improved by nearly three times. Crucially, due to the chemical bonding of hydrophobic side chains to the main chains, the PBADT films exhibited excellent stability in its water vapor barrier performance under external mechanical friction. Furthermore, DDSA introduction markedly reduced haze and increased light transmittance, demonstrating improved optical clarity. On the other hand, the existence of the long alkylene side chain of DDSA also significantly inhibited the crystallization and mechanical properties of the copolyesters. Full article

The lower melt strength of biodegradable materials in comparison to low density polyethylenes raises serious issues regarding their processability via blown film molding. Thus, reliable rheological characterization is a viable option for assessing their efficient flow performance. The blends of poly (lactic acid) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) modified with four chain-extending cross-linkers (CECLs) undergo shearing during extrusion and are subjected to extensional deformation during the subsequent film blowing. The shear viscosity data obtained with a capillary rheometer corresponded well to the molecular weights obtained by gel permeation chromatography, while an evaluation of elongational viscosity using a Sentmanat Extensional Rheometer failed due to sample sagging during the process of temperature setting and an unacceptable deviation from the theoretically supposed exponential decrease of sample cross-sections. Therefore, the response of the PBAT/PLA blends to elongation was determined via changes in the duration of time intervals corresponding to the rupture of elongated samples. An increased consistency of the PBAT/PLA blends with CECL, as previously indicated by dynamic mechanical analysis, differential scanning calorimetry, and scanning electron microscopy, was evaluated in this way. Full article

To address the inherent challenge of poor interfacial compatibility in lignin/poly(butylene adipate-co-terephthalate) (PBAT) composites, lignin was extracted from Camellia oleifera shells and subjected to sequential solvent fractionation using ethanol, acetone, and tetrahydrofuran (THF). Two representative fractions—acetone-soluble (ACL) and THF-soluble (THFL)—were selected for composite preparation with PBAT via solvent casting. The influence of lignin fractionation on the structural and performance characteristics of the resulting composites was systematically evaluated through Fourier-transform infrared (FTIR) spectroscopy, the water contact angle (WCA), differential scanning calorimetry (DSC), tensile testing, and scanning electron microscopy (SEM). The results revealed that the abundant hydroxyl groups and benzene rings present in both ACL and THFL facilitated hydrogen bonding and conjugation interactions with the PBAT matrix, significantly improving interfacial adhesion. Notably, the ACL fraction effectively suppressed phase separation and increased the glass transition temperature (T_g) by 1.9 °C, leading to a 13.9% enhancement in tensile strength compared to neat PBAT. More strikingly, the incorporation of only 7 wt% THFL resulted in a remarkable 31% improvement in tensile strength. This substantial enhancement was primarily attributed to the favorable polarity match between THFL and PBAT, as well as the nucleating effect of THFL, which increased the crystallinity of PBAT by 25.3%. This study highlights the effectiveness of sequential lignin fractionation in tailoring the interfacial properties of biodegradable polymer composites. It also provides a promising strategy for the high-value utilization of lignin toward the development of high-performance, environmentally friendly materials. Full article