Poly Lactic Acid Research Articles

Properties of polylactic acid/gelatin/acetyl tributyl citrate blend materials

AbstractThe inherent brittleness and high cost of polylactic acid (PLA) hinder its further application. Developing low‐cost, flexible, and biodegradable gelatin (GEL)‐modified PLA is a way to broaden the application prospects of PLA applications. Acetyl tributyl citrate (ATBC) was added to overcome the process difficulty of PLA/GEL melt blending and toughening the blends. Maleic anhydride (MAH) grafted PLA (PLA‐g‐MAH) was prepared to improve the compatibility of the PLA/GEL/ATBC. Because of the interface, physical and chemical interaction induced by PLA‐g‐MAH, the compatibility among PLA, GEL, and ATBC was enhanced, which significantly improved the plasticizing efficiency of ATBC. Results showed that the elongation at break of the blends can be improved by 491%, 68 times higher than that of pristine PLA. Moreover, the modified blends did not break under the conditions of notch impact, which exhibited excellent toughness. The blends possessed a high degradation rate owing to the hydrophilic gelatin and PLA‐g‐MAH, significantly accelerated the degradation process of PLA. The prepared PLA/GEL/ATBC/PLA‐g‐MAH biomass blended plastics exhibited good comprehensive performance, with true sustainability and environmental friendliness.

Enhancing the strength and toughness of polylactic acid through fused deposition modeling‐induced orientation and nucleation effects of attapulgite

AbstractSimultaneously enhancing strength and toughness through simple and low‐cost methods has always been a challenge for polylactic acid (PLA) materials. In this context, natural attapulgite (ATT) nanorods were used as fillers combined with fused deposition modeling (FDM) to improve the strength and toughness of PLA. The printable PLA nanocomposite filaments filled with ATT nanorods were prepared by melting compounding and smoothly printed via a commercial FDM three‐dimensional (3D) printer. The influences of FDM process and ATT filling on the properties of PLA/ATT composite parts were evaluated through microstructure analysis, rheological, and mechanical tests. The results suggest that PLA/ATT composite parts manufactured by FDM exhibit superior mechanical properties, which can be attributed to the FDM induced orientation and nucleation effect of ATT nanorods. The tensile strength can reach 56 MPa with the addition of 2 wt% ATT at a nozzle temperature of 205°C, increasing by 24% compared to pure PLA. In addition, the fracture elongation of PLA/ATT parts printed by FDM has significantly increased to 26%, which is 924% higher than pure PLA. Furthermore, the filling of ATT significantly improves the storage modulus of composite parts. This work provides a new high‐strength, ultra tough, low‐cost, and printing stable PLA/ATT composite material and forming method, offering a promising avenue for the wider application of PLA and ATT in the future.

Construction of high-performance and sustainable polylactic acid composites for 3D printing applications with plasticizer

Polylactic acid (PLA) attains much attention because of its biodegradability, biocompatibility, and high strength, but its further application was remarkably hindered by its brittleness. In order to improve the toughness of PLA, a biodegradable composite was prepared by blending ductile polycaprolactone (PCL), stiff microcrystalline cellulose (MCC), and green plasticizer tributyl citrate (TBC) with PLA by melting extrusion. The physicochemical properties and microstructure of PLA composites were thoroughly investigated using FTIR, TGA, DSC, XRD, melting rheology, optical transmittance, 3d printing, tensile tests, and SEM. The tensile tests results show that introduction of TBC exhibited a remarkable improvement effect in the elongation at break of PLA/PCL/MCC (PPM) composite, increasing from 2.9 % of PPM to up to 30 % of PPM/6TBC and PPM/8TBC. Noticeably, the strength of PPM/TBC composites (at least 33.1 MPa) was enhanced compared with that of PPM (28.2 MPa). The plasticization of TBC, enhancing the compatibility of composites, and reinforcing effect of MCC were identified as pivotal factors in toughening and reinforcing PLA. Furthermore, it is observed that the incorporation of TBC contributed to enhanced thermal stability, crystallinity, and rheology property of composites. This research supplies a novel approach to bolstering the toughness of PLA and broaden its potential applications.

Unveiling the potential of cellulose, chitosan and polylactic acid as precursors for the production of green carbon nanofibers with controlled morphology and diameter

Carbon nanofibers (CNFs) are very promising materials with application in many fields, such as sensors, filtration systems, and energy storage devices. This study aims to explore the use of eco-friendly biopolymers for CNF production, finding novel, suitable and sustainable precursors and thus prioritising environmentally conscious processes and ecological compatibility.Polymeric nanofibers (PNFs) using cellulose acetate, polylactic acid, and chitosan as precursors were successfully prepared via electrospinning. Rheological testing was performed to determine suitable solution concentrations for the production of PNFs with controlled diameter and appropriate morphology. Their dimensions and structure were found to be significantly influenced by the solution concentration and electrospinning flow rate. Subsequently, the electrospun green nanofibers were subject to stabilisation and carbonisation to convert them into CNFs. Thermal behaviour and chemical/structural changes of the nanofibers during stabilisation were investigated by means of thermogravimetric analysis and Fourier-transform infrared spectroscopy, while the final morphology of the fibers after stabilisation and carbonisation was examined through scanning electron microscopy to determine the optimal stabilisation parameters. The optimal fabrication parameters for cellulose and chitosan-based CNFs with excellent morphology and thermal stability were successfully established, providing valuable insight and methods for the sustainable and environmentally friendly synthesis of these promising materials.

Supercritical CO2 extrusion foaming of highly open-cell poly(lactic acid) foam with superior oil adsorption performance

Addressing marine oil spills and industrial water pollution necessitates the development of eco-efficient oil-absorbing materials. With increasing concern for the environment, there is a consensus to decrease the use of petroleum-based polymers. Herein, lightweight poly(lactic acid) (PLA) blend foams with varying thermoplastic polyurethane (TPU) content were fabricated via a solvent-free, eco-friendly supercritical carbon dioxide (scCO2) extrusion foaming technology. The incorporation of TPU significantly enhanced the crystallization rate of PLA, with the semi-crystallization time of PT30 and PT50 blends at 105 °C exhibiting a reduction of 77.2 % and 47.9 %, respectively, compared to neat PLA. The resulting foams exhibited an open-cell structure with excellent selective oil adsorption capabilities. Notably, the PT30 foam achieved a remarkable maximum expansion ratio of 36.0, while the PT50 foam attained the highest open-cell content of 96.2 %. The PT50 foam demonstrated an outstanding adsorption capacity, spanning from 4.7 to 18.8 g/g for diverse oils and solvents, with rapid adsorption kinetics, reaching 94.9 % of the equilibrium adsorption capacity for CCl4 within just 1 min. Furthermore, the PT50 foam retained 95.2 % of its adsorption capacity for CCl4 over 10 adsorption-desorption cycles. This study presents a scalable and sustainable approach for large-scale production of high-performance, bio-based foams, facilitating efficient oil-water separation.

Sonochemical synthesis of bioinspired graphene oxide–zinc oxide hydrogel for antibacterial painting on biodegradable polylactide film

Graphene oxide nanosheet (GO) is a multifunctional platform for binding with nanoparticles and stacking with two dimensional substrates. In this study, GO nanosheets were sonochemically decorated with zinc oxide nanoparticles (ZnO) and self-assembled into a hydrogel of GO–ZnO nanocomposite. The GO–ZnO hydrogel structure is a bioinspired approach for preserving graphene-based nanosheets from van der Waals stacking. X-ray diffraction analysis (XRD) showed that the sonochemical synthesis led to the formation of ZnO crystals on GO platforms. High water content (97.2%) of GO–ZnO hydrogel provided good property of ultrasonic dispersibility in water. Ultraviolet-visible spectroscopic analysis (UV–vis) revealed that optical band gap energy of ZnO nanoparticles (∼3.2 eV) GO–ZnO nanosheets (∼2.83 eV). Agar well diffusion tests presented effective antibacterial activities of GO–ZnO hydrogel against gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus). Especially, GO–ZnO hydrogel was directly used for brush painting on biodegradable polylactide (PLA) thin films. Graphene-based nanosheets with large surface area are key to van der Waals stacking and adhesion of GO–ZnO coating to the PLA substrate. The GO–ZnO/PLA films were characterized using photography, light transmittance spectroscopy, coating stability, scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopic mapping (EDS), antibacterial test and mechanical tensile measurement. Specifically, GO–ZnO coating on PLA substrate exhibited stability in aqueous food simulants for packaging application. GO–ZnO coating inhibited the infectious growth of E. coli biofilm. GO–ZnO/PLA films had strong tensile strength and elastic modulus. As a result, the investigation of antibacterial GO–ZnO hydrogel and GO–ZnO coating on PLA film is fundamental for sustainable development of packaging and biomedical applications.

Dimensional accuracy of acrylonitrile butadiene styrene and polylactic acid samples printed in vacuum-assisted material extrusion system

This paper discusses the impact of integrating a vacuum system into a material extrusion 3D printing process for acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) materials. The study aimed to investigate the effect of a vacuum system on the dimensional accuracy of the printed samples. Upon completion of the printing process, the samples’ dimensions were carefully assessed using a Coordinate Measuring Machine (CMM). The geometrical dimensions measured are the diameter, corner radius, fillet, thickness, width, length and angle. Based on the result obtained, the material has yet to reach 100% of the desired geometry, which was identified due to the shrinkage of the material after the printing process. The results show that the vacuum system improved material flow and reduced dimensional deviations by reducing air molecules and minimizing convection. The results indicated a significant enhancement in dimensional accuracy for both ABS and PLA samples when using the vacuum system. ABS samples showed a 4% increase in accuracy, while PLA samples exhibited a 2% improvement compared to samples printed without vacuum assistance. These improvements were achieved by optimizing process parameters such as layer height (0.15 mm), infill percentage (10%), printing speed (45 mm s−1), and bed temperature (60 °C). These parameters were selected to ensure finer details, improved precision, structural support, stability, better adhesion, and reduced warping.

Optimisation of printing parameters of fused filament fabrication and uniaxial compression failure analysis for four-point star-shaped structures

PurposeThe purpose of this paper is to present an optimisation of four-point star-shaped structures produced through additive manufacturing (AM) polylactic acid (PLA). The study also aims to investigate the compression failure mechanism of the structure.Design/methodology/approachA Taguchi L9 orthogonal array design of the experiment is adopted in which the input parameters are resolution (0.06, 0.15 and 0.30 mm), print speed (60, 70 and 80 mm/s) and bed temperature (55°C, 60°C, 65°C). The response parameters considered were printing time, material usage, compression yield strength, compression modulus and dimensional stability. Empirical observations during compression tests were used to evaluate the load–response mechanism of the structures.FindingsThe printing resolution is the most significant input parameter. Material length is not influenced by the printing speed and bed temperature. The compression stress–strain curve exhibits elastic, plateau and densification regions. All the samples exhibit negative Poisson’s ratio values within the elastic and plateau regions. At the beginning of densification, the Poisson’s ratios change to positive values. The metamaterial printed at a resolution of 0.3 mm, 80 mm/s and 60°C exhibits the best mechanical properties (yield strength and modulus of 2.02 and 58.87 MPa, respectively). The failure of the structure occurs through bending and torsion of the unit cells.Practical implicationsThe optimisation study is significant for decision-making during the 3D printing and the empirical failure model shall complement the existing techniques for the mechanical analysis of the metamaterials.Originality/valueTo the best of the authors’ knowledge, for the first time, a new empirical model, based on the uniaxial load response and “static truss concept”, for failure mechanisms of the unit cell is presented.

3D printed plant-based biodegradable materials as alternative for PVC panels in monitoring coastal marine communities

Coastal marine environments are some of the most productive and overexploited ecosystems on earth. Coastal ecosystems, like oyster and coral reefs, need physical structures to establish and habitat destruction has led to the destabilization of reef structures resulting in massive biodiversity losses. For decades, researchers have utilized PolyVinyl Chloride (PVC) panels as artificial larval settlement panels to study recruitment and community dynamics in these incredibly important ecosystems. Unfortunately, PVC itself is relatively toxic, the panels are smooth which makes it difficult for larval settlement, and it can take months to see establishment because larvae need settlement cues on PVC from biofilm development. This study assessed the use of 3D printed panels constructed out of plant-based biodegradable materials as an alternative to PVC panels. Panels constructed of three different corn-based polylactic acid (PLA) materials (white impact modified, gray impact modified, wood pulp) were tested at a well monitored site along the Long Island Sound in Connecticut, US. Overall, the 3D printed panels had equal or higher recruitment compared to the PVC panels. Beyond the normal application of panels for ecological assessment of local settlement, this work highlights that using innovative, biodegradable panels has strong potential in reestablishing these overburdened yet critical ecosystems. Additionally, the 3D printed panels were economically beneficial to use, which increases equity in this conservation crisis field as material expense can be cost prohibitive.

Continuous preparation and antibacterial mechanisms of biodegradable polylactic acid/nano-zinc oxide/additives antibacterial non-wovens

Biodegradable polylactic acid (PLA)/nano‑zinc oxide (ZnO)/additives non-woven slices were prepared by melt blending method. The effects of antibacterial agent nano-ZnO, antioxidant pentaerythrityl tetrakis-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate (1010), and chain extender multi-functional epoxy (ADR), on the melt flow rate, mechanical properties, thermal stabilities and micromorphology of the slices were investigated. The melt flow rate decreased from 26.94 g/10 min to 17.76 g/10 min, and the tensile strength increased from 10.518 MPa to 30.427 MPa with the increase of nano-ZnO and additives content. The slices were further spunbonded. The wettability and antibacterial properties of PLA/nano-ZnO/additives antibacterial non-wovens were studied, and the antibacterial action mechanism was clarified. The results showed that the biodegradable PLA/nano-ZnO/additives antibacterial non-wovens were prepared continuously successfully. The prepared non-woven fabrics exhibited good hydrophobicity and antibacterial properties. The mechanism study shows that zinc ion produced by nano-ZnO and photocatalytic reaction make the fabrics have good antibacterial activity at low nano-ZnO content. When nano-ZnO concentration reaches 1.5 wt%, the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches 98.52 % and 98.13 %, respectively.

Synergistic effects of nucleating agent, chain extender and nanocrystalline cellulose on PLA and PHB blend films: Evaluation of morphological, mechanical and functional attributes

The current study focuses on reactive extrusion of poly (lactic acid) (PLA) and polyhydroxybutyrate (PHB) based blend films using epoxide styrene–acrylic (ESA) chain extender, pentaerythritol (PEOL) as a nucleating agent and cellulose nanocrystal (CNC). The blown films were subjected to various mechanical, thermal, barrier, and microstructural analyses to determine their suitability for packaging. Test results indicated that the incorporation of 0.5 wt% of chain extender significantly improved the elastic modulus and yield strength of PLA/PHB blend films. Further addition of 1 wt% of PEOL improved the crystallinity as well as mechanical strength in the films. FTIR analysis suggested chain conformations in different crystalline regions of PLA/PHB blend films whereas nucleation density and arrangement in crystal growth have been analysed by POM and SEM micro graphical studies. Additionally, the presence of CNCs within the PLA/PHB blend films showed an improved water vapour transmission rate (WVTR) of 90.53 g/m2.day revealing the creation of a tortuous path. Evaluation of optimum glossiness and haze of the films were done and the co-efficient of friction analysis depicted more anti-slip properties of the films.

SC crystals of porous PLA via thermally–induced phase separation: Effects of process conditions, solvent composition and nucleating agent

The formation of stereo-complex crystals (SC) in porous poly (lactic acid) (PLA) material is intricately linked with improving its comprehensive properties. In this work, the effects of process conditions, solvent composition and additional nucleating agent on SC crystals during the fabrication of porous PLA through thermally-induced phase separation method were studied. Crystallization behavior of SC crystals during the pore-forming process is systematically investigated, revealing that higher quenching temperature and longer quenching period facilitate the formation of SC crystals. Additionally, the addition of deionized water to the solvent effectively enhances SC crystals formation by reducing solution viscosity and prolonging the phase separation time. The highest crystallinity of SC crystals (XSC) can be achieved, reaching 30.6%, when the water content is controlled at 1.6%. Furthermore, the introduction of carbon nanotubes (CNTs) as a nucleating agent exhibits a pronounced effect on the formation of SC crystals. When incorporating a 3 wt% content of CNTs, XSC reaches its peak value at 37.7%. This work is helpful to provide reference for improving mechanical properties and heat resistance of porous PLA, thereby expanding its potential outdoor applications.

Evaluation of particle and volatile organic compound emissions during the use of 3D pens

This study investigated particle and volatile organic compound (VOC) emission rates (ER) from 3D pens, which are increasingly popular in children's toys. Nine filaments and two 3D pens were evaluated using a flow tunnel, a scanning mobility particle sizer, a proton-transfer-reaction time-of-flight mass spectrometer for particles, and a thermal desorption-gas chromatography-mass spectrometer for VOCs. Results showed that the ERs varied with the pen type, filament, and brand. The particle ER was highest for acrylonitrile butadiene styrene (ABS), followed by polylactic acid (PLA) and polycaprolactone (PCL). Notably, ERs of 83 % and 33 % of ABS and PLA filaments exceeded the maximum allowable particle ER (MAER; 5 × 109 particles/min) for 3D printers but were lower than the VOC MAER (173 μg/min in the office). Different filaments emitted diverse VOCs; ABS emitted styrene and benzene, PLA emitted lactide, and PCL emitted phenol. While particle ERs from 3D pens were comparable to those from printers, the total VOC ERs from 3D pens were slightly lower. Caution is warranted when using 3D pens because of potential health risks, especially their prolonged use, proximity to the breathing zone, and usage by children. This study highlights the need for considering particles and VOCs when assessing the safety of 3D pens, emphasizing awareness of potential hazards, particularly in child-oriented settings.

Tailoring electrospun nanocomposite fibers of polylactic acid for seamless methylene blue dye adsorption applications.

The introduction of biopolymers, which are sustainable and green materials, desegregated nature's water purification proficiency with science and technology, opens a new sustainable methodology in water reclamation. In order to introduce an efficacious adsorbent system for MB dye-toxic pollutant, adsorption, providing robust mechanical properties and facile processability, a facile system was introduced via electrospinning utilizing polylactic acid (PLA) and Ti3C2Tx, viz., PMX. The addition of 3 wt.% Ti3C2Tx led to a 3-fold substantial augmentation in the uptake capacity of the membrane from 197.28 to 307 mg/g when the adsorbate concentration was 100 ppm. The adsorption followed a PSO behavior, proposing that the rate-limiting stage is chemisorption and data best fitted to Freundlich isotherm, indicating heterogeneous adsorption sites and multi-layer adsorption. Further, biodegradability was studied by simulating natural environmental conditions where the nanofibers exhibited 42-64% degradation after 270 days. Based on the result with PLA, it is anticipated that the prepared fibrous system will introduce a new perspective as a potential candidate for MB removal from wastewater, opening new directions toward the research and development in wastewater treatment with electrospun biopolymer fibers using waste PLA.

Effects of polyethylene and biodegradable microplastics on the physiology and metabolic profiles of dandelion

Biodegradable plastics, such as poly(butylene adipate terephthalate) (PBAT) and polylactic acid (PLA), are potential alternatives to conventional polyethylene (PE), both of which are associated with the production of microplastics (MPs). However, the toxicity of these compounds on medicinal plants and their differential effects on plant morphophysiology remain unclear. This study supplemented soils with MPs sized at 200 μm at a rate of 1% w/w and incubated them for 50 days to investigate the impact of MPs on the growth and metabolites of dandelion (Taraxacum mongolicum Hand.-Mazz.). The results demonstrated that the investigated MPs decreased the growth of dandelion seedlings, induced oxidative stress, and altered the activity of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase). Based on the comprehensive toxicity assessment results, the ecological toxicity was in the following order: PE MPs > PBAT MPs > PLA MPs. Metabolomics analyses revealed metabolic reprogramming in dandelion plants, leading to the enrichment of numerous differentially accumulated metabolites (DAMs) in the leaves. These pathways include carbohydrate metabolism, energy metabolism, and biosynthesis of secondary metabolites, suggesting that dandelions respond to MP stress by enhancing the activity of sugar, organic acid, and amino acid metabolic pathways. In addition, phenolic acids and flavonoids are critical for maintaining the balance in the antioxidant defense system. Our results provide substantial insights into the toxicity of biodegradable MPs to plants and shed light on plant defense and adaptation strategies. Further assessment of the safety of biodegradable MPs in terrestrial ecosystems is essential to provide guidance for environmentally friendly management.

Effect of hydrophobic modification of chitin nanocrystals on role as anti-nucleator in the crystallization of poly(ε-caprolactone)/polylactide blend

Biodegradable polymer blends filled with rod-like polysaccharide nanocrystals have attracted much attention because each component in this type of ternary composites is biodegradable, and the final properties are more easily tailored comparing to those of binary composites. In this work, chitin nanocrystals (ChNCs) were used as nanofiller for the biodegradable poly(ε-caprolactone) (PCL)/polylactide (PLA) immiscible blend to prepare ternary composites for a crystallization study. The results revealed that the crystallization behavior of PCL/PLA blend matrices strongly depended on the surface properties of ChNCs. Non-modified ChNCs and modified ChNCs played completely different roles during crystallization of the ternary systems: the former was inert filler, while the latter acted as anti-nucleator to the PCL phase. This alteration was resulted from the improved ChNC-PCL affinity after modification of ChNCs, which was due to the ‘interfacial dilution effect’ and the preferential dispersion of ChNCs. This work presents a unique perspective on the nucleation role of ChNCs in the crystallization of immiscible PCL/PLA blends, and opens up a new application scenario for ChNCs as anti-nucleator.

Recent development of poly (lactic acid) blends with a thermoplastic elastomer compatibilised for fused deposition modelling (FDM) 3D printing

Recent development of poly (lactic acid) blends with a thermoplastic elastomer compatibilised for fused deposition modelling (FDM) 3D printing

Polylactic Acid Composite Nonwoven Fabric Incorporating Nano-Silver Coated Titanium Dioxide for Photocatalytic Degradation of Carbaryl in Water

Polylactic Acid Composite Nonwoven Fabric Incorporating Nano-Silver Coated Titanium Dioxide for Photocatalytic Degradation of Carbaryl in Water

Accelerated hydrolysis and degradation of polylactide nanocomposites using loaded silica nanocarriers

Polylactide (PLA) stands as a prominent commodity biodegradable polymer, yet its inherent slow biodegradation under certain conditions has been a persistent challenge. This study introduces a general approach for enhancing the biodegradation of PLA by employing silica nanoparticles (SiNPs) loaded with diverse cargoes. The SiNPs with diameters of ca. 100 nm are synthesized through a sol–gel process in an inverse microemulsion, enabling in situ loading with functional cargoes such as poly(acrylic acid), lignosulfonate, and chitosan. Surface grafting with PLA (PLA-grafted SiNPs) serves to prevent aggregation, thereby enhancing the dispersion of nanoparticles within the PLA matrix and improving composite properties preventing depletion. Lignin-loaded SiNPs demonstrate the capability to block UV light and enhance antioxidant activity in the composite compared to neat PLA. Notably, SiNPs loaded with poly(acrylic acid) and chitosan exhibit the capacity to accelerate PLA hydrolysis in aqueous environments, while lignin as cargo results in faster composting with an increased weight loss of ca. 20 wt% compared to neat PLA at only 1 wt% loading of SiNPs. This research outlines a versatile strategy utilizing SiNPs to address the slow biodegradation profile of PLA, offering valuable insights and a promising avenue for advancing the environmental sustainability of degradable polyester-based materials in diverse applications.

Dimensional and Structural Instability of Electrospun Polylactic Acid Membranes in Liquid Environments: Role of Water, Ethanol, and Temperature

AbstractElectrospun nanofibres of polylactic acid (PLA) are suggested for a variety of uses, including scaffolds for tissue engineering, components of drug delivery devices, sustainable packaging materials and membranes for liquid filtration/purification. For all these applications, it is critical to consider the stability of the PLA electrospun materials once in operation. Exposure to certain liquids and temperatures can modify their dimensions, shape, surface topography and mechanical response and compromise their performance. In this study, electrospun PLA mats were exposed to water and ethanol solutions, at different temperatures and for defined time periods, and changes in their properties were analysed. It was found that the impact of water on area shrinkage and fibre arrangement strongly depended on temperature, particularly if the treatment was performed at the glass transition temperature of PLA. Ethanol, instead, induced significant alterations in the size, morphology, and elastic modulus of the electrospun mats, even at room temperature and determined the formation of crimped structures. This work provides insights into the conditions that can critically affect the properties of PLA electrospun fibres and, hence, impact on their usage.