Miguel Ribeiro

Ms. Miguel Ribeiro

University of Coimbra, CEMMPRE – Chemical Engineering Department, FCTUC, Polo 2, Pinhal de Marrocos, Coimbra 3030-290, Portugal.
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
28 December 2022 in Cellulose
Verified
Journal Article
Open access
PDF file
Rafael C. RebeloRafael C. Rebelo
Rafael C. Rebelo
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
Patrícia Alexandra Nunes PereiraPatrícia Alexandra Nunes Pereira
Patrícia Alexandra Nunes Pereira
FBFrancesco De Bon
Francesco De Bon
JCJorge Coelho
Jorge Coelho
ASArmenio Serra
Armenio Serra
A process was developed combining two natural-based products to obtain bio-based films. Industrial cellulose pulp was dissolved and mixed with epoxidized soybean oil (ESBO), which acts as an internal plasticizer. A distillable and recyclable ionic liquid-based solvent was used to dissolve the cellulose. Appropriate distribution of the cellulose/ESBO solution on glass surfaces and careful regeneration of the cellulose enabled the development of solvent-free and flexible cellulose films. Fourier transform infrared spectroscopy revealed the presence of the triglyceride structure and the absence of the epoxide ring in the films, confirming the chemical reaction between the hydroxyl and epoxide groups of cellulose. The resulting films were further characterized by scanning electron microscopy, dynamic scanning calorimetry, thermogravimetry, and mechanical tensile tests. The films were also evaluated by contact angle measurement, swelling ability, in vitro degradability and cytotoxicity. The results showed that the presence of ESBO can adjust both the flexibility and hydrophilicity of the cellulose films, resulting in materials suitable for a variety of applications.

28 May 2021 in Polymers
Verified
Journal Article
Open access
PDF file
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
Rafael C. RebeloRafael C. Rebelo
Rafael C. Rebelo
FBFrancesco De Bon
Francesco De Bon
JCJorge Coelho
Jorge Coelho
ASArmenio Serra
Armenio Serra
Due to environmental concerns, more attention has been given to the development of bio-based materials for substitution of fossil-based ones. Moreover, paper use is essential in daily routine and several applications of industrial pulp can be developed. In this study, transparent films were produced by industrial cellulose pulp solubilization in tetramethylguanidine based ionic liquids followed by its regeneration. Films were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV/Vis spectroscopy, proton nuclear magnetic resonance (1H-NMR), dynamic scanning calorimetry (DSC), thermal analysis (TG), and X-ray diffraction (XRD). Mechanical tests showed that films have a good elongation property, up to 50%, depending on ionic liquid incorporation. The influence of the conjugated acid and dissolution temperature on mechanical properties were evaluated. These results revealed the potential of this methodology for the preparation of new biobased films.

22 May 2019 in Obesity Surgery
Verified
Journal Article
Closed access
PDF file
Hans EickhoffHans Eickhoff
Hans Eickhoff
TRTiago Rodrigues
Tiago Rodrigues
INInês Neves
Inês Neves
DMDaniela Marques
Daniela Marques
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
Paulo N. MatafomePaulo N. Matafome
Paulo N. Matafome

22 November 2025 in Lubricants
Verified
Journal Article
Open access
PDF file
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
Amilcar RamalhoAmilcar Ramalho
Amilcar Ramalho
ASArmenio Serra
Armenio Serra
JCJorge Coelho
Jorge Coelho
The growing demand for sustainable and high-performance lubricants has accelerated interest in biolubricants derived from renewable feedstocks. Vegetable oils are attractive candidates due to their biodegradability, low toxicity, and favorable viscosity index. However, their application is limited by poor oxidative and thermal stability. The epoxidation of unsaturated fatty acids offers a versatile route to address these drawbacks by enhancing stability and introducing reactive epoxy groups for further functionalization. This review highlights the advances in the use of epoxidized vegetable oils (EVOs), as platforms for lubricant design. Post-epoxidation modifications, such as ring-opening reactions, crosslinking, hybridization with additives, and click-type chemistries, are critically examined with emphasis on their impact on viscosity, polarity, tribofilm formation, and overall tribological behaviour. Structure–property relationships were discussed to establish design principles linking chemical modifications with lubrication regimes, wear resistance, and film-forming ability. In addition, sustainability aspects, including biodegradability, ecotoxicity, and life cycle assessment, are reviewed to evaluate the trade-offs between performance enhancement and environmental compatibility of these modifications. Current challenges and future perspectives are outlined, including the need for standardized testing protocols, the integration of multifunctional modifications, and predictive modelling tools. By bridging molecular engineering, tribological performance, and sustainability, this review provides a roadmap for the rational design of advanced epoxidized oil-based biolubricants.

17 November 2022 in Polymers
Verified
Journal Article
Open access
PDF file
FBFrancesco De Bon
Francesco De Bon
IAInês M. Azevedo
Inês M. Azevedo
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
Rafael C. RebeloRafael C. Rebelo
Rafael C. Rebelo
JCJorge Coelho
Jorge Coelho
ASArmenio Serra
Armenio Serra
Electrochemically mediated atom transfer radical polymerization (eATRP) is developed in dispersion conditions to assist the preparation of cellulose-based films. Self-degassing conditions are achieved by the addition of sodium pyruvate (SP) as a ROS scavenger, while an aluminum counter electrode provides a simplified and more cost-effective electrochemical setup. Different polyacrylamides were grown on a model cellulose substrate which was previously esterified with 2-bromoisobutyrate (-BriB), serving as initiator groups. Small-scale polymerizations (15 mL) provided optimized conditions to pursue the scale-up up to 1000 mL (scale-up factor ~67). Cellulose-poly(N-isopropylacrylamide) was then chosen to prepare the tunable, thermoresponsive, solvent-free, and flexible films through a dissolution/regeneration method. The produced films were characterized by Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), dynamic scanning calorimetry (DSC), and thermogravimetric analysis (TGA).

26 June 2025 in Fuel
Verified
Journal Article
Open access
Miguel RibeiroMiguel Ribeiro
Miguel Ribeiro
ASArmenio Serra
Armenio Serra
JCJorge Coelho
Jorge Coelho
Amilcar RamalhoAmilcar Ramalho
Amilcar Ramalho