RT journal article
T1 Fused Granulate Fabrication of Virgin and Reprocessed PLA/Silicon Dioxide Nanocomposites: Processing, Mechanical Integrity, and Soil Microbial Respiration Response
A1 Bergaliyeva, Saltanat
A1 Romero Ocaña, Ismael
A1 Innocenti, Alessandro
A1 Burgos Pintos, Pedro
A1 Silva García, Blanca Gema
A1 Baladés Ruiz, Nuria
A1 Molina Rubio, Sergio Ignacio
A1 Sales Lérida, David
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
A2 Ingeniería Industrial e Ingeniería Civil
A2 Ingeniería Mecánica y Diseño Industrial
K1 hybrid materials
K1 mechanical properties
K1 thermal properties
K1 soil respiration
K1 fused granular fabrication
K1 silicon dioxide
AB This study evaluates processing via fused granulate fabrication (FGF) of nanocomposites based on virgin polylactic acid (PLA) and thermomechanically reprocessed polylactic acid (rPLA), incorporated with 0 wt%, 5 wt%, and 10 wt% of silicon dioxide (SiO2) nanoparticles. Rheological analysis revealed that rPLA exhibited a 42.4 % increase in melt flow rate compared to PLA, which can be attributed to thermomechanical chain scission occurring during reprocessing. At 10 wt% filler loading, the tensile strength along the XZ build direction tended to decrease. Scanning electron microscopy analysis suggests that this trend is related to nanoparticle agglomeration. Thermogravimetric analysis showed that adding 5–10 wt% SiO2 restored the lower initial thermal degradation onset of rPLA (𝑇�5%loss=313°C) to values equal to or exceeding PLA (323–324°C), while overall crystallinity remained near 0% owing to rapid convective cooling during FGF printing. Short-term soil respirometry trials using extruded granule samples revealed that rPLA exerted a temporary respirometric inhibition, reducing soil basal respiration by 22.5%. The incorporation of 10 wt% SiO2 recovered 96.3% of the native soil metabolic activity by increasing extruded granules surface wettability and water availability at the particle interface. These findings demonstrate that the control of SiO2 loading enables the tuning of mechanical performance, establishing a framework for sustainable, large-format PLA components with tailored end-of-life properties.
PB MDPI, Basel, Switzerland
SN 2504-4494
YR 2026
FD 2026-10-15
LK http://hdl.handle.net/10498/40530
UL http://hdl.handle.net/10498/40530
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 08-nov-2026