查找使用阿拉丁产品的科研文献

Valorizing Waste Fly Ash Cenospheres: Towards Multifunctional PLA Composites With Improved Flame Retardancy and Thermal Insulation

Guowei Liu,Rui Pan,Erlei Yu,Xiaolong Hu,Rui Hu

To valorize industrial waste and enhance polylactic acid (PLA), this study hypothesizes that functionalizing hollow fly ash cenospheres (FAC) with a phosphorus-nitrogen system creates a synergistic flame-retardant and thermal insulating additive. Accordingly, a multifunctional filler (FAC-KH550-PA-MEL) was synthesized and characterized via Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). PLA composites were subsequently evaluated using thermogravimetric analysis (TGA), limiting oxygen index (LOI), cone calorimetry, and thermal conductivity measurements. Results demonstrate that 5 wt% additive enabled PLA to achieve a UL-94 V-0 rating and an LOI of 31.8%, with a 28.06% reduction in peak heat release. These improvements stem from a synergistic mechanism: phytic acid (PA) promotes condensed-phase charring, melamine (MEL) provides gas-phase dilution, and the silicate skeleton of FAC acts as a thermal barrier. Furthermore, the unique hollow structure of FAC reduced thermal conductivity by 36.25% to 0.0712 W/(m K). This confirms that low-loading functionalized FAC effectively yields high-performance, multifunctional PLA composites.

Simultaneous Enhancement of Ductility and Impact Toughness in Biodegradable PLA/PCL Blends via a Plasticizer Strategy

Junrui Duan,Yuesheng Zhang,Zhiguo Hu,Hongtao Lu,Jianna Bao

Although blending brittle polylactide (PLA) with flexible poly(ε-caprolactone) (PCL) holds promise for developing biodegradable materials with tunable mechanical properties, their poor compatibility poses a significant challenge to effective toughening. In this study, PLA/PCL blends with varying Dibutyl itaconate (DBI) content were prepared via melt blending, and the effects of DBI loading on the properties of the blends were systematically investigated. The results demonstrated that the incorporation of DBI enhanced the intermolecular interactions between PLA and PCL chains, thereby improving their compatibility. The phase interface between the PLA matrix and the PCL dispersed phase became so progressively blurred with increasing DBI content that it was nearly indistinguishable at a loading of 7 phr, demonstrating a significant improvement in compatibility. With the increase in DBI content, both the elongation at break and impact strength of the blends exhibited a trend of initial increase followed by a decrease. At the optimal loading, the maximum values reached 314.3% and 29.5 kJ/m 2 , representing enhancements of 3.4-fold and 4.9-fold, respectively, compared to those of the neat PLA/PCL blend. Simultaneously, the crystallization rate and enzymatic degradation rate of the blends increased continuously with higher DBI content. This study opens a new avenue for developing high-toughness PLA-based blend materials without compromising their biodegradability. Summary DBI enhanced both elongation at break and impact strength of PLA/PCL blends. The incorporation of DBI improved the compatibility between PLA and PCL. The crystallization capability of the modified blends was enhanced. The modified blends showed an increased degradation rate.

Preparation and properties of polylactic acid (PLA) antibacterial nanofiber membrane with Ag@TP composite antibacterial agent

Jie Wu,Shuqiang Liu,Gaihong Wu,Man Zhang,Yifan Jing,Jingjing Li,Md Moinul Hossain Patowary,Romen Chakma,Cailiu Wang,Fu Li,Lu Jia,Yujing Zhang,Dongdong Lu

This paper presented the composite antibacterial agent of nano-silver (Ag) and tea polyphenol (TP) by bioreduction method. Then polylactic acid (PLA) nanofiber membranes with different antibacterial content were prepared by electrostatic spinning method. The morphologies, structural characteristics and properties of electrostatic spun fiber membranes were investigated by scanning electron microscope (SEM), infrared spectroscopy (FTIR), electronic single fiber strength machine and flat colony counting method. The results showed that Ag@TP was loaded with silver nanoparticles with uniform particle size distribution. When the content of Ag@TP of electrospun fiber was less than 2.0%, the diameter of electrostatic spinning fiber was uniformly distributed and had smooth surface. It could be seen from the FTIR spectrum that Ag@TP and PLA were well compounded through valence bonds. As the content of antibacterial agent increased, the elongation at break of the fiber membrane first decreased and then increased. While the breaking strength was found to first decrease, then increase and decrease again. The water contact angle of the fiber membrane was gradually decreased with the increase of the antibacterial agent content. When the amount of Ag@TP was added 2.0%, the relative antibacterial rate of the electrospun fiber membrane to E.coli and S.aureus was as high as 95%, indicating an excellent antibacterial effect.

Long chain alkyl grafted cellulose and PBST synergistically reinforce PLA: Balanced strength, toughness, and barrier properties

Baotong Chen,Erman Su,Ruxangul Jamal,Abdukeyum Abdurexit,Tursun Abdiryim,Lei Wang,Qingwen Sang,Ruixue Ma

Using waste cotton stalk fibers to prepare highly hydrophobic eMCC for PLA composites. • As a nucleating agent, eMCC enhances PLA crystallinity and crystallization rate. • Hydrogen bonding and van der Waals forces give composite ductility and barrier. • It presents a novel strategy for sustainable applications of PLA-based eco-friendly materials. Poly(lactic acid) (PLA) is a promising biodegradable polymer, yet its inherent brittleness, poor barrier properties, and slow crystallization rate limit its application in food packaging. In this study, hydrophobically modified microcrystalline cellulose (eMCC) and poly(butylene succinate- co -terephthalate) (PBST) were incorporated into PLA via solution casting to prepare a ternary composite with balanced properties. Characterization by polarized optical microscopy, X-ray diffraction, and differential scanning calorimetry demonstrated that eMCC promoted heterogeneous nucleation of PLA under isothermal conditions, while PBST served as a ductile toughening phase. Owing to synergistic interfacial interactions, primarily hydrogen bonding and van der Waals forces, eMCC was uniformly dispersed and exhibited strong interfacial adhesion with both polymer phases. The resulting composite achieved a tensile strength of 39.7 MPa while retaining a high elongation at break of 199.9%, reflecting a favorable balance between stiffness and toughness. Barrier property measurements revealed that the water vapor and oxygen barrier properties were improved by 18.0% and 26.1%, respectively, compared with neat PLA. This work provides an effective strategy for utilizing hydrophobically modified microcrystalline cellulose to develop food packaging materials with high performance and potential biodegradability. Download: Download high-res image (190KB) Download: Download full-size image

Toughening PLA via Diisocyanate-Induced Dynamic Vulcanization of Carboxylated Oleic Acid: Role of Crosslinked Network Topology

Diisocyanate-induced dynamic vulcanization of difunctional fatty acids has emerged as a universal strategy to efficiently improve the impact resistance of polylactic acid (PLA). However, how the crosslinked network topology of the in situ formed polyamide elastomer (COPA) affects its toughening efficacy on PLA remains unknown. Here, we synthesized two carboxylated fatty acids with distinct molecular architectures (TCOA and NCOA) from technical-grade and high-purity oleic acids via UV-initiated thiol-ene click chemistry. These two diacids, along with tetradecanedioic acid (TA) without a dangling chain, were dynamically vulcanized with hexamethylene diisocyanate (HDI) to toughen PLA. By varying NCO/COOH molar ratios between HDI and TCOA, their effects on gel content, crosslinking density, phase morphology, and mechanical properties of resulting blends were systematically investigated. With increasing the ratio, both gel content and interfacial adhesion with PLA in the blends were enhanced, accompanied by the transformation of phase structure from “sea-island” morphology to a partially or fully co-continuous one. At a molar ratio of 1.8:1, the notched impact strength value of the blend reached 86.5 kJ/m2. By substituting TCOA with high-purity NCOA or TA, comparable gel content and interfacial compatibilization level, and co-continuous morphologies were achieved. Notably, NCOA yielded a PLA blend with a remarkably higher impact toughness (131.0 kJ/m2). The linear chain structure of TA led to a higher crosslinking density of the formed TAPA domains, which unfavorably suppressed their cavitation during impact fracture and thus resulted in an inferior impact strength (7.0 kJ/m2). These findings provide valuable insights into the toughening mechanism of PLA via dynamic vulcanization of monomers.

PLA-Derived High-Barrier Slow-Release Antibacterial Film: Industrial-Scale Preparation and Enhanced Preservation of Salmon

Zukang Yang,Jiahua Chang,Wenya Ma,Qingfeng Dong,Min Fan,Kunpeng Qian,Li Li

This study developed an industrially scalable, fully bio-based multilayer film for sustainable packaging of high-fat aquatic products. The film combines high barrier properties with long-acting antimicrobial function through a tailored structure: Outer polylactic acid (PLA)/poly (butylene adipate-co-terephthalate) (PBAT) and intermediate polyvinyl alcohol (PVA) barrier layers, and an inner PLA/PBAT/thermoplastic starch (TPS) blend layer serving as a reservoir. To enable sustained release, a β-cyclodextrin-carvacrol inclusion complex (β-CD@CAR), prepared by saturated aqueous solution, was incorporated into this reservoir layer. The resulting film showed excellent barrier performance (OTR: 298.9 ± 6.1 cm 3 /[m 2 ·24h·0.1 MPa]; WVTR: 146.21 ± 41.45 g/[m 2 ·24 h]) and robust mechanical properties (tensile strength: 27.32 ± 5.12 MPa; elongation at break: 72.15 ± 11.22%). The β-CD@CAR complex provided controlled CAR release, imparting strong antibacterial activity (reductions of 1.88 and 2.01 log CFU/g against Staphylococcus aureus [ S. aureus ] and Escherichia coli [ E. coli ], respectively). When applied to salmon preservation, the film effectively delayed microbial growth, pH increase, color deterioration, quality loss, and protein oxidation, extending shelf life by at least four days. This work demonstrates a scalable strategy for active packaging by integrating a multilayer barrier with a cyclodextrin-mediated release system, showing significant industrial potential for preserving perishable, high-fat foods. Notably, the film was fabricated via industrially viable melt-extrusion and thermal lamination. This scalable approach, combined with the tailored multilayer architecture, represents a significant advance towards practical active packaging.

Arg-PCN/PLA Nanocomposite Membranes with Enhanced Antibacterial Efficacy via Red Light-Triggered PDAT/NO Synergism

Limo Wang,Bingjie Xu,Xinting Dong,Danfeng Jian,Tianming Lu,Yujie Gao,Jindan Wu

The misuse of antibiotics has resulted in multidrug resistance among bacteria, rendering nearly all conventional antibiotics ineffective and creating a pressing global need for highly efficient and broad-spectrum antibacterial alternatives. Photodynamic antibacterial therapy (PDAT) has emerged as a promising strategy to address bacterial resistance; however, its efficacy is limited by inherent challenges such as poor tissue penetration, short diffusion ranges, and brief half-lives of reactive oxygen species (ROS). In this study, we developed an antibacterial composite nanofiber membrane with red light responsiveness by incorporating functional l-arginine-modified PCN-224 nanoparticles (Arg-PCN NPs), which enabled NO-enhanced synergistic PDAT. Specifically, Arg-PCN NPs were synthesized and subsequently embedded into a polylactic acid (PLA) matrix by electrospinning, yielding a porous nanocomposite membrane (APM). Under irradiation, APM showed a strong synergistic antibacterial effect, and the bactericidal rate against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) reached 99.9%. Comprehensive mechanistic studies revealed that APM potently enhanced bacterial membrane permeability and elevated intracellular ROS levels upon irradiation. Furthermore, cytotoxicity assays confirmed that APM exhibited negligible in vitro cytotoxicity. The red light-activated antibacterial membrane developed in this work holds significant potential for wound care applications and provides a design strategy for advanced antibacterial materials capable of combating drug-resistant bacterial infections.

Pickering-Stabilized Breath Figure Assembly of CNWs-TiO2/PLA Porous Films: Synergistic Reinforcement and Functional Grading

Ting Zhang,Junhao Liang,Bin Wang,Bohua Wen,Zhengyang Xi,Xuyang Zhao,Xinhai He

(1) Background: The development of biodegradable polymers with enhanced functionality is critical for advancing sustainable packaging technologies. This study addresses the challenge of simultaneously improving the structural rigidity and functional performance of poly(lactic acid) (PLA) materials. (2) Methods: Cellulose nanowhisker (CNW) and TiO 2 nanoparticle (Nano-TiO 2 ) reinforced PLA porous composite films were fabricated via a nanoparticle-assisted breath figure method. The effects of these hybrid nanoparticles on the morphology, thermal stability, and structure of the resulting composites were systematically investigated. (3) Results: The incorporation of CNWs and Nano-TiO 2 played a dual role: they acted as Pickering-like stabilizers at the water/polymer interface, preventing droplet coalescence and facilitating the formation of a well-defined honeycomb-like porous structure. They also significantly enhanced the relative crystallinity of the PLA matrix from 20.26% to 36.31%, owing to the heterogeneous nucleation effect. Consequently, the mechanical properties were significantly enhanced, with the maximum tensile strength and Young’s modulus increasing by 123.3% and 21.9%, respectively. Furthermore, the composite films exhibited excellent UV-shielding performance, achieving an SR UV-B of 97.6%. (4) Conclusions: The synergistic reinforcement of CNWs and Nano-TiO 2 effectively endows PLA composites with superior mechanical properties and functional protection. These findings establish the CNWs-Nano-TiO 2 /PLA composite film as a promising candidate for high-performance smart packaging applications.

Eugenol-confined ZIF-8 modulates PLA nanofiber architecture for synergistic low-resistance and antibacterial PM filtration

Kaixin Qian,Xiao Ma,Mei Hong,Fuping Qian

Conventional air filtration media struggle to simultaneously address secondary biological pollution, the efficiency-permeability trade-off, and the environmental burden associated with disposable polymer filters. Direct blending of agglomerated or dense fillers can destabilize the electrospinning jet, disrupting the fiber network and increasing airflow resistance. In this study, biodegradable PLA nanofibers were combined with eugenol-loaded ZIF-8 nanoparticles to construct an antibacterial air filtration membrane. Prepared through an aqueous route, ZIF-8 served a dual function by regulating the architecture of the fibrous network and acting as a microporous reservoir for the natural antibacterial molecule eugenol. Comparison of pristine PLA, PLA/ZIF-8, and PLA/EUG@ZIF-8 membranes clarified each component's contribution. Pristine PLA provided a biodegradable fibrous matrix but showed inadequate filtration and negligible antibacterial activity. The incorporation of ZIF-8 optimized membrane morphology, enhanced particle capture, and imparted moderate bacterial inhibition. Notably, confinement of eugenol within ZIF-8 pores further enhanced antibacterial activity without disrupting the optimized membrane structure or air permeability. The PLA/EUG@ZIF-8 membrane delivered PM0.3, PM1.0, and PM2.5 filtration efficiencies of 99.62%, 99.99%, and 99.99%, respectively, with a low pressure drop of 69 Pa and a maximum quality factor of 0.1335 Pa⁻¹ . The composite also achieved near-complete inhibition of Escherichia coli (99.74%) and Staphylococcus aureus (99.48%). Numerical simulations showed a filtration trend consistent with the experimental results, indicating that the improved performance was mainly associatedwith the optimized fiber-pore structure rather than simple membrane densification. Thus, MOF-mediated natural antibacterials effectively fabricate biodegradable filters with excellent PM capture, low resistance, and strong antibacterial activity, promoting eco-friendly membranes.

Multifunctional modifier coupled with premixing for PLA/CNT composites with ultra‑high toughness and superior functionality

Junjie Ma,Xing Li,Haiyan Zhu,Jing Huang,Ting Li,Yang Wang,Shibo Wang,Xuhui Zhang,Weifu Dong

Polymer/carbon nanotube (CNT) nanocomposites are promising structural-functional integrated materials, but achieving ultra-high toughness and excellent functionality for rigid polymer/CNT composites remains challenging. Herein, a strategy combining a multifunctional modifier and premixing technique was developed to synchronously achieve the ultra‑high toughness and enhanced functionality of poly(lactic acid) (PLA)/CNT composites, a representative of rigid polymer/CNT nanocomposites. The modified tannic acid (mTA), featuring low T g , abundant benzene rings and grafted isopropanol oligomers, serves as a multifunctional modifier to toughen PLA/CNT composites, establish π-π interactions with CNTs and form hydrogen bonding with PLA. Premixing CNTs with sufficient mTA favors the coating of CNTs by mTA, enabling mTA to effectively inhibit CNT re-agglomeration. Consequently, this strategy synchronously optimizes CNT dispersion, enhances interfacial adhesion, and toughens PLA/CNT composites. The optimal PLA/mTA15/CNT2 achieves an unprecedented integration of ultra-high toughness (165.1 ± 9.3 MJ/m 3 ) and obviously improved functionality (electrical conductivity and EMI shielding effectiveness). The composite also exhibits superior melt processability and 3D printability, enabling the fabrication of complex components. This work offers a promising route for developing high-performance structural–functional integrated materials, and will promote the practical applications of PLA/CNT composites in antistatic packaging, flexible electronics, and electromagnetic interference shielding materials.

Eco-Friendly PLA/PBAT Janus Nanofibers Featuring Tensile-Induced Flux Enhancement for Selective Oil–Water Separation

Xinlong Liu,Xujie Wang,Zifan Xu,Xin Zhang,Guohua Sun,Lianlong Hou,Tiantian Li,Pengpeng Li

Membrane-based oil–water separation has attracted extensive attention as an efficient and energy-saving strategy for oily wastewater treatment; however, most conventional separation membranes are fabricated from petroleum-based polymers, which are difficult to degrade after disposal and may cause secondary environmental pollution. Therefore, developing high-performance oil–water separation membranes with environmental sustainability remains a critical challenge. In this work, a biodegradable PLA/PBAT Janus nanofibrous membrane is fabricated via dual-channel side-by-side electrospinning using polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) as the polymer matrix. Hydrophilic and underwater oleophobic modification of the membrane is achieved through a mild interfacial microswelling process, which introduces hydrophilic functional groups and enhances surface roughness. As a result, the modified membrane exhibits significantly improved wettability, with the water contact angle reduced to approximately 20° and the underwater–oil contact angle exceeding 130°. Benefiting from the aligned nanofiber arrangement, interconnected porous structure, and the stretchability of PBAT, the hydrophilic PLA/PBAT Janus membrane demonstrates excellent separation performance toward oil-in-water emulsions under gravity-driven conditions, achieving a high permeation flux of up to 2985 L·m–2·h–1 under tensile deformation and maintaining a stable flux of approximately 1000 L·m–2·h–1 after 120 separation cycles, while oil rejection efficiencies remain around 98% for different oil phases. This study demonstrates that biodegradable Janus nanofibrous membranes based on PLA and PBAT can simultaneously achieve high separation efficiency, mechanical robustness, and environmental sustainability, providing a promising green membrane material for efficient oil–water separation applications.

Preparation, characterization and antibacterial evaluation of PLA/ZnO nanofiber membranes loaded with thymol by coaxial electrospinning

Dan Huang,SuQiu Si,Zhuoming Chen,Binjie Xin

In this study, a novel nanofiber material possessing antibacterial and antioxidant properties was fabricated through coaxial electrospinning, utilizing polylactic acid (PLA), thymol (THY), and nano zinc oxide (ZnO) as the raw materials. THY and ZnO was used to endows the membranes with good antibacterial and antioxidant properties. The surface morphology of the PLA/Z@T nanofiber membrane was characterized using scanning electron microscopy (SEM). Additionally, the successful formation of the core-shell structure was verified through transmission electron microscopy (TEM), fluorescence microscopy, and Fourier transform infrared spectroscopy (FTIR). Additionally, both ZnO and THY exhibit strong antibacterial properties, and their synergistic effect significantly enhances the antibacterial activity of the composite nanofiber membranes against Staphylococcus aureus . The drug sustained release percentages within 24 h for PLA@T and PLA/Z@T were 15.91 % and 14.82 %, respectively. The addition of zinc oxide does not significantly affect the release efficiency of thymol. After continuous release for 288 h, these percentages increased to 73.35 % and 72.94 %, respectively. By assessing antioxidant activity through DPPH and ABTS assays, it was found that PLA/Z@T exhibited higher activity compared to the control group. Subsequently, the in vitro antibacterial performance was investigated, revealing an antibacterial rate higher than that of the control group, the antibacterial rates against Staphylococcus and Escherichia coli reached 99.75 % and 98.49 % respectively. In conclusion, the results demonstrate that PLA/Z@T nanofiber membranes possess excellent antibacterial efficiency, sustained antibacterial performance, and antioxidant properties, offering a novel strategy for antibacterial materials.