Jean Andre Medina

Dr. Jean Andre Medina

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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1 October 2021 in European Polymer Journal
Verified
Journal Article
Closed access
PSPatricio A. Sobarzo
Patricio A. Sobarzo
AMAndrea Paz Marimán
Andrea Paz Marimán
CSChristian O. Sánchez
Christian O. Sánchez
RHRené A. Hauyon
René A. Hauyon
FRFidel E. Rodríguez-González
Fidel E. Rodríguez-González
CTClaudio A. Terraza
Claudio A. Terraza

24 December 2022 in Polymers
Verified
Journal Article
Open access
PDF file
RHRene Hauyon
Rene Hauyon
DFDenis Fuentealba
Denis Fuentealba
NPNancy Pizarro
Nancy Pizarro
MOM. Carmen Ortega-Alfaro
M. Carmen Ortega-Alfaro
VUVíctor M. Ugalde-Saldívar
Víctor M. Ugalde-Saldívar
CTClaudio Terraza
Claudio Terraza
In the search for solution-processable TADF materials as a light emitting layer for OLED devices, polymers have attracted considerable attention due to their better thermal and morphological properties in the film state with respect to small molecules. In this work, a new polymer (p-TPS-DMAC-TRZ) with thermally activated delayed fluorescence (TADF) light-emitting characteristics was prepared from a conjugation-break unit (TPS) and a well-known TADF core (DAMC-TRZ). This material was designed to preserve the photophysical properties of DAMC-TRZ, while improving other properties, such as thermal stability, promoted by its polymerization with a TPS core. Along with excellent solubility in common organic solvents such as toluene, chloroform and THF, the polymer (Mn = 9500; Mw = 15200) showed high thermal stability (TDT5% = 481 °C), and a Tg value of 265 °C, parameters higher than the reference small molecule DMAC-TRZ (TDT5% = 305 °C; Tg = 91 °C). The photoluminescence maximum of the polymer was centered at 508 nm in the solid state, showing a low redshift compared to DMAC-TRZ (500 nm), while also showing a redshift in solution with solvents of increasing polarity. Time-resolved photoluminescence of p-TPS-DMAC-TRZ at 298 K, showed considerable delayed emission in solid state, with two relatively long lifetimes, 0.290 s (0.14) and 2.06 s (0.50), and a short lifetime of 23.6 ns, while at 77 K, the delayed emission was considerably quenched, and two lifetimes in total were observed, 24.6 ns (0.80) and 180 ns (0.20), which was expected from the slower RISC process at lower temperatures, decreasing the efficiency of the delayed emission and demonstrating that p-TPS-DMAC-TRZ has a TADF emission. This is in agreement with room temperature TRPL measurements in solution, where a decrease in both lifetime and delayed contribution to total photoluminescence was observed when oxygen was present. The PLQY of the mCP blend films with 1% p-TPS-DMAC-DMAC-TRZ as a dopant was determined to be equal to 0.62, while in the pure film, it was equal to 0.29, which is lower than that observed for DMAC-TRZ (0.81). Cyclic voltammetry experiments showed similarities between p-TPS-DMAC-TRZ and DAMC-TRZ with HOMO and LUMO energies of −5.14 eV and −2.76 eV, respectively, establishing an electrochemical bandgap value of 2.38 eV. The thin film morphology of p-TPS-DMAC-TRZ and DMAC-TRZ was compared by AFM and FE-SEM, and the results showed that p-TPS-DMAC-TRZ has a smoother surface with fewer defects, such as aggregations. These results show that the design strategy succeeded in improving the thermal and morphological properties in the polymeric material compared to the reference small molecule, while the photophysical properties were mostly maintained, except for the PLQY determined in the pure films. Still, these results show that p-TPS-DMAC-TRZ is a good candidate for use as a light-emitting layer in OLED devices, especially when used as a host-guest mixture in suitable materials such as mCP.

1 April 2021 in European Polymer Journal
Verified
Journal Article
Closed access
IJIgnacio A. Jessop
Ignacio A. Jessop
AMAndrea Paz Marimán
Andrea Paz Marimán
PSPatricio A. Sobarzo
Patricio A. Sobarzo
RHRené A. Hauyon
René A. Hauyon
CSCésar Saldías
César Saldías
CTClaudio A. Terraza
Claudio A. Terraza

13 February 2025 in European Polymer Journal
Verified
Journal Article
Closed access
JMJean Andre Medina
Jean Andre Medina
PSPatricio A. Sobarzo
Patricio A. Sobarzo
RHRené A. Hauyon
René A. Hauyon
LGLuis E. Garcia
Luis E. Garcia
EGEnzo B. González
Enzo B. González
CTClaudio Terraza
Claudio Terraza

15 August 2025 in Materials Advances
Verified
Journal Article
Open access
PDF file
JMJean Andre Medina
Jean Andre Medina
AMAngela Matarín
Angela Matarín
PSPatricio Sobarzo
Patricio Sobarzo
CTClaudio Terraza
Claudio Terraza
EMEva M Maya
Eva M Maya
A polymeric support based on a poly(azomethine) (PAM) structure was synthesized using mechanochemical polymerization (PAM@M) and compared with its counterpart prepared via conventional high-temperature solution-phase polycondensation (PAM@T). The mechanochemical approach not only significantly reduced the synthesis time (1 hour versus 24 hours), but also resulted in a polymer with amorphous character while the one synthesized via conventional heating exhibits some crystalline peaks. FePAM@M demonstrated superior catalytic performance with complete conversion of glycerol to solketal with 100% selectivity in only 1 hour at room temperature, exhibiting an impressive environmental factor (E-factor = 3.49). The conversion of glycerol into value-added products is essential due to its large-scale generation as a by-product of biodiesel, so the results of this work highlight FePAM@M as a highly efficient and sustainable catalyst for this valorisation.

2 September 2025 in Polymer
Verified
Journal Article
Closed access
PSPatricio A. Sobarzo
Patricio A. Sobarzo
DPDanitza Pavez-Lizana
Danitza Pavez-Lizana
JMJean Andre Medina
Jean Andre Medina
RHRené A. Hauyon
René A. Hauyon
LGLuis E. Garcia
Luis E. Garcia
CTClaudio Terraza
Claudio Terraza