Microstructural Effect of Extrusion-Blended PLA/BaTiO3 Composite: SEM and XRD Analysis
Bibliographic record
Abstract
Polymer-ceramic composites are trending due to their exceptional strength-to-weight ratio, making them excellent candidates for various applications [1]. The aim of this study is to explore the microstructural properties that BaTiO3 can exhibit within a matrix of polylactic acid (PLA) undergoing an additive manufacturing process. The composite was prepared by extrusion mixing, with the main objective of fabricating the filaments that would be used to print a three-dimensional scaffold using triple periodic surface minimum geometry (TPMS) [2]. The model was generated using computational coding techniques, specifically, employing the Schwarz equation to generate a primitive porous scaffold using Python programming language coding (Fig. 1a). BTO-PLA composite was obtained by mixing 10 wt. % of BaTiO3 powder, 85 wt. % of PLA 4060D and 5 wt. % of glycerin. An extruder (Brabender Plasticorder) was used to produce a filament of 0.175 cm diameter, at a speed of 15 RPM, a die extrusion temperature of 155°C, and an extruder screw temperature of 140 °C. The morphological characteristics of the composite were analyzed by scanning electron microscopy (SEM), the global and punctual elemental analysis was performed by energy dispersive X-ray spectroscopy (EDS) and its structural characterization by X-ray diffraction (XRD). SEM micrographs taken from the cross-section of the filament were collected with a JEOL- JSM-7401F instrument. It was observed a rough texture for PLA accompanied by a distribution of agglomerated BaTiO3 particles (Fig. 1b-c). The global elemental mapping (EDX) confirms a dispersion of the BaTiO3 particles in the very homogeneous polymer matrix, highlighting the presence of Ba and Ti (Fig. 1d-g). The XRD pattern of the BTO-PLA composite was obtained in an X'Pert Pro diffractometer in the Bragg-Brentano geometry employing the Cu Kα radiation (λ = 1.5418 Å). The XRD pattern was refined through the Rietveld method using the FullProf software and the SH method. The lattice parameters obtained in this refinement were a = b = 3.999 Å and c = 4.026 Å (Figure 2a). The XRD pattern was indexed with PDF file No. 75-1606 associated with a perovskite-type structure with tetragonal phase and P4mm symmetry (No. 99). The crystal shape was elucidated using the GFourier program in a three-dimensional and a bidimensional (2D) view (Fig. 2b-c). A distinctive morphology of a quasi-cubic with prominent peaks can be observed. This crystal shape can be attributed to the inherent crystallographic structure of BaTiO3 combined with the constraints imposed by the PLA matrix during the formation of the composite. In addition, the extrusion process during filament preparation could have influenced the crystalline morphology. Extrusion introduces shear forces and mechanical stress, which can alter the orientation and shape of crystallites within the composite, potentially, contributing to the observed distortion. This morphology may have significant implications for the mechanical and piezoelectric properties of the composite, warranting further investigation. A BTO-PLA composite was successfully obtained through extrusion manufacturing. The BTO particles are homogeneously dispersed over the PLA matrix. The XRD analysis confirms a tetragonal phase and the elemental microanalysis confirms the presence of Ba, Ti, and O. This work also paves the way for further research into the potential applications of PLA/BaTiO3 composites in fields such as additive manufacturing, biomedical engineering and electronics [3-5]. Furthermore, the use of TPMS geometry in composite fabrication offers unique opportunities for the design of tailored materials, aiming to improve mechanical properties and allowing the exploration of new functionalities [6]. (a) Design of BTO/PLA composite scaffold, (b) Cross-section SEM micrograph with magnification of 500x and (c) x1000 of BTO/PLA filament, while images (d-h) show the elemental mapping for Ba, Ti, O. (a) XRD Rietveld refinement of the extruded composite, (b) average crystallite shape in 2D obtained with GFourier software using SH method, and (c) apparent crystallite (quasi-cubic) shape for BTO/PLA composite after the extrusion process.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".