2023 Photography Contest Winner

Filament of a bundle of 24,000 continuous carbon fibers coated with polycarbonate (PC) to obtain reinforced parts by 3D printing. Author: Enrique Hernández Murillo

Filament of a bundle of 24,000 continuous carbon fibers coated with polycarbonate (PC) to obtain reinforced parts by 3D printing.
Filament of a bundle of 24,000 continuous carbon fibers coated with polycarbonate (PC) to obtain reinforced parts by 3D printing. | Photo: Enrique Hernández

Cross section SEM micrograph of a continuous carbon fiber (CCF) filament is shown in the figure above. This filament consist of multiple continuous carbon fibers embedded in a thermoplastic matrix (polycarbonate). The filament has an average diameter of 1.75mm and has approximately 24,000 carbon fibers with an individual diameter of 7μm. As it can be observed, the carbon fibers are uniformly distributed in the center of the polycarbonate matrix, and a large central fiber-rich region is clearly distinguishable. In areas without matrix where fibers remain unimpregnated, small voids could be seen, resulting in a weaker surface bond between fibers and thermoplastic. These defects can be attributed to the high melt viscosity of the polycarbonate, which complicates the mobility of the polymer chains during fiber fabrication by coextrusion.

The function of this coating is exclusively that of a vehicle to be able to 3D print the reinforcement fibers. Filament extrusion was performed In a Brabender Plasticorder PLE-650 extruder machine with a screw aspect ratio L/D = 25 and with a coaxial extrusion mold, while filament winding was performed by a strand pelletizer adapted for non pelletizing. The procedure of the extrusion starts with the CCF spooled on a winding and fed into the coaxial extrusion mold, while the thermoplastic pellet that will act as the thermoplastic coating is fed into the extruder. The molten thermoplastic is compressed around the fiber in the nozzle. After coating, the CCF filament is cooled in a water bath to solidify. Finally, the strand pelletizer pulls the strand and keeps the processing speed constant.

2022 Photography contest winner

Photo: “Perfect combination of Science”. Compatibility between Styrene-Acrylonitrile (SAN) copolymer and Polybutadiene (PB) polymer phases to obtain high performance latexes. Author: Ms. Ainara Agirre


2D-STEM micrograph of a dry acrylonitrile-butadiene-styrene (ABS) latex is observed in the left image. ABS latex with 36 % of solid content was synthetized by seeded semi-batch emulsion polymerization. For the sample preparation, the ABS latex was first dialyzed to remove adsorbed species on the surface of the particles, mainly to avoid staining of the surfactant used during the grafting reaction. Then, the polymer latex was dried on a Transmission Electron Microscopy (TEM) grid and stained with OsO4 for one hour, which selectively reacted with the vinylic bonds of the PB. In HAADF-STEM, the contrast of the image is opposite to common TEM micrographs, which means that the PB matrix phase stained with OsO4 will correspond to the bright area while the SAN phases (shell and clusters) to the dark. The image presents the 2D-STEM tomographic image at position OZ = 124 of the particle, where the OZ axis coincides with the direction of the electron beam, and the OY axis is the tilting axis. 

2021 Photography contest winner.

Photo: "Nanotubos oníricos: Una danza celeste". Author: Ms. Bertha Teresa Pérez Martínez.


Micrografía SEM a 1.467X de magnitud, con un HV de 10.00kV (WD: 10.6 mm). Fractura de una película polimérica compuesta de metacrilatos (MMA/BA/HEMA) en precencia de nanotubos de carbono multipared (0.5%) mediante polimerización en miniemulsión. Los nanotubos previos a la polimerización fueros sometidos a un tratamiento de ultrasonido en agua y en presencia de polyvinilpirrolidona. Después de la polimerización a 70ºC, el látex obtenido fue de color negro y homógeno sin cuágulos y estable.

2020 Photography contest winner

Honeycomb-like microstructured materials for mechanically strong polymer films. Author: Ms. Nerea Jiménez

TEM micrograph of a cross-section of an acrylic polymer film for coatings applications. In the image, the darkest component forms a honeycomb microstructure around the lightest phase. The dark phase was composed of tannic acid, a naturally occurring polyphenol, and the light phase was consisting of poly(N-vinyl pyrrolidone-co-butyl acrylate-co-methyl methacrylate) (P(NVP/BA/MMA) polymer particles produced by seeded semibatch emulsion polymerization. For the preparation of the sample, 5% based on polymer of tannic acid was added as an aqueous solution to the P(NVP/BA/MMA) polymer dispersion. The blend was stirred for 30 minutes, cast into a silicone mould and dried for 7 days at 55 % relative humidity and 25 ºC. The resulting polymer film was cut employing a microtome and stained with ruthenium tetraoxide (RuO4) in order to increase the contrast of the aromatic rings of tannic acid. The staining process allowed the observation of the honeycomb microstructure formed by tannic acid around the polymer particles. The honeycomb microstructure was formed as a result of the strong hydrogen bonds between the aromatic hydroxyl groups of tannic acid and the amide groups of the pyrrolidones present in the polymer, which promoted the homogeneous distribution of tannic acid around the polymer particles. This conclusion was made by comparing the microstructure of the materials prepared without the pyrrolidone: The tannic acid formed aggregates instead of the continuous honeycomb microstructure. The P(NVP/BA/MMA)/tannic acid hydrogen bonded materials presented greater Young’s modulus and yield stress as a result of the hard honeycomb structure. The high stiffness presented by these materials make them excellent candidates for applications that require hard polymer films and opens the way for the complete replacement of solventborne coatings.

2019 Photography contest winner

Description: AFM phase image of a double crystalline PE494.9-b-PEO515.2 diblock copolymer. The long edge on lamellae in the center of the image correspond to the polyethylene block crystals. To the top and the bottom of the image, flat on lamellae can be observed, which can correspond to both PE and PEO block crystals. The thin vertical short lamellae on the middle of the image (looking like fish bones) are most probably poly(ethylene oxide) lamellae. Author: Ms. Eider Matxinandiarena

2018 Photography contest winner

2018 Awarded picture: "Centipede" by Mr. Jesus Alvaro Iregui. Description: AFM phase image of an electrospun PCL-DGEBA nanofiber. Due to the spinning process, it is observed a high degree of crystalline orientation

4th Scientific Photography Award

Awarded picture: AFM phase image of the top surface of a dried film of latex with particles polymerized in presence of cellulose nanocrystals. Elodie Limousin

3rd Scientific Photography Award

"The eyes": Double crystalline nascent spherulite. AFM micrographs of a PEO-b-PCL diblock copolymer taken at a room temperature by Ms. Jordana Palacios.

1st Scientific Photography Award

Awarded Picture:
Awarded Picture: "SEM micrograph of a dispersion of fluorinated polymer particles" by Ms. Ana Belén López

First Edition Photographs presented Pdf version