This page has only limited features, please log in for full access.

Mrs. Daniel Ura
International Centre of Electron Microscopy for Materials Science, Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland

Basic Info


Research Keywords & Expertise

0 Electron Microscopy
0 Electrospinning
0 Mechanical Testing Of Materials
0 Surface Chemistry
0 polymer

Fingerprints

fibers
Electrospinning
polymer
surface properties
Surface Chemistry
Electron Microscopy

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 19 May 2021 in Composites Science and Technology
Reads 0
Downloads 0

An understanding of the reinforcement mechanism in composites is crucial for the development of novel materials where the application is limited by their mechanical properties. One of the methods used to obtain high performance composites is reinforcement with short fibers. Polymeric materials, such as electrospun polymethyl methacrylate (PMMA) fibers, have a very high tendency to fragment into regular short fibers after applying very low stress. This phenomenon was used to reinforce a polycarbonate (PC) core-shell structure (PMMA-PC) by using fragmented short PMMA fibers for reinforcement in the critical length limits. Mechanical testing revealed an increase of maximum stress and Young's modulus of almost 260% and 630%, respectively, for PMMA-PC fiber meshes. The observation of core-shell fibers after mechanical testing was confirmed by using confocal microscopy, showing very regular short fragments of PMMA fibers inside the PC shell. This work demonstrates a hierarchical approach that can be taken for reinforcement of a single fiber on the nanoscale and a composite on the macroscale.

ACS Style

Daniel P. Ura; Krzysztof Berniak; Urszula Stachewicz. Critical length reinforcement in core-shell electrospun fibers using composite strategies. Composites Science and Technology 2021, 211, 108867 .

AMA Style

Daniel P. Ura, Krzysztof Berniak, Urszula Stachewicz. Critical length reinforcement in core-shell electrospun fibers using composite strategies. Composites Science and Technology. 2021; 211 ():108867.

Chicago/Turabian Style

Daniel P. Ura; Krzysztof Berniak; Urszula Stachewicz. 2021. "Critical length reinforcement in core-shell electrospun fibers using composite strategies." Composites Science and Technology 211, no. : 108867.

Research article
Published: 26 April 2021 in ACS Nano
Reads 0
Downloads 0

Access to clean water is a global challenge, and fog collectors are a promising solution. Polycarbonate (PC) fibers have been used in fog collectors but with limited efficiency. In this study, we show that controlling voltage polarity and humidity during the electrospinning of PC fibers improves their surface properties for water collection capability. We experimentally measured the effect of both the surface morphology and the chemistry of PC fiber on their surface potential and mechanical properties in relation to the water collection efficiency from fog. PC fibers produced at high humidity and with negative voltage polarity show a superior water collection rate combined with the highest tensile strength. We proved that electric potential on surface and morphology are crucial, as often designed by nature, for enhancing the water collection capabilities via the single-step production of fibers without any postprocessing needs.

ACS Style

Daniel P. Ura; Joanna Knapczyk-Korczak; Piotr K. Szewczyk; Ewa A. Sroczyk; Tommaso Busolo; Mateusz M. Marzec; Andrzej Bernasik; Sohini Kar-Narayan; Urszula Stachewicz. Surface Potential Driven Water Harvesting from Fog. ACS Nano 2021, 15, 8848 -8859.

AMA Style

Daniel P. Ura, Joanna Knapczyk-Korczak, Piotr K. Szewczyk, Ewa A. Sroczyk, Tommaso Busolo, Mateusz M. Marzec, Andrzej Bernasik, Sohini Kar-Narayan, Urszula Stachewicz. Surface Potential Driven Water Harvesting from Fog. ACS Nano. 2021; 15 (5):8848-8859.

Chicago/Turabian Style

Daniel P. Ura; Joanna Knapczyk-Korczak; Piotr K. Szewczyk; Ewa A. Sroczyk; Tommaso Busolo; Mateusz M. Marzec; Andrzej Bernasik; Sohini Kar-Narayan; Urszula Stachewicz. 2021. "Surface Potential Driven Water Harvesting from Fog." ACS Nano 15, no. 5: 8848-8859.

Journal article
Published: 31 December 2020 in Membranes
Reads 0
Downloads 0

Atopic dermatitis (AD) is a chronic, inflammatory skin condition, caused by wide genetic, environmental, or immunologic factors. AD is very common in children but can occur at any age. The lack of long-term treatments forces the development of new strategies for skin regeneration. Polycaprolactone (PCL) is a well-developed, tissue-compatible biomaterial showing also good mechanical properties. In our study, we designed the electrospun PCL patches with controlled architecture and topography for long-term release in time. Hemp oil shows anti-inflammatory and antibacterial properties, increasing also the skin moisture without clogging the pores. It can be used as an alternative cure for patients that do not respond to traditional treatments. In the study, we tested the mechanical properties of PCL fibers, and the hemp oil spreading together with the release in time measured on skin model and human skin. The PCL membranes are suitable material as patches or bandages, characterized by good mechanical properties and high permeability. Importantly, PCL patches showed release of hemp oil up to 55% within 6 h, increasing also the skin moisture up to 25%. Our results confirmed that electrospun PCL patches are great material as oil carriers indicating a high potential to be used as skin patches for AD skin treatment.

ACS Style

Sara Metwally; Daniel P. Ura; Zuzanna J. Krysiak; Łukasz Kaniuk; Piotr K. Szewczyk; Urszula Stachewicz. Electrospun PCL Patches with Controlled Fiber Morphology and Mechanical Performance for Skin Moisturization via Long-Term Release of Hemp Oil for Atopic Dermatitis. Membranes 2020, 11, 26 .

AMA Style

Sara Metwally, Daniel P. Ura, Zuzanna J. Krysiak, Łukasz Kaniuk, Piotr K. Szewczyk, Urszula Stachewicz. Electrospun PCL Patches with Controlled Fiber Morphology and Mechanical Performance for Skin Moisturization via Long-Term Release of Hemp Oil for Atopic Dermatitis. Membranes. 2020; 11 (1):26.

Chicago/Turabian Style

Sara Metwally; Daniel P. Ura; Zuzanna J. Krysiak; Łukasz Kaniuk; Piotr K. Szewczyk; Urszula Stachewicz. 2020. "Electrospun PCL Patches with Controlled Fiber Morphology and Mechanical Performance for Skin Moisturization via Long-Term Release of Hemp Oil for Atopic Dermatitis." Membranes 11, no. 1: 26.

Journal article
Published: 16 October 2020 in Fibers
Reads 0
Downloads 0

Processing parameters in electrospinning allow us to control the properties of fibers on a molecular level and are able to tailor them for specific applications. In this study, we investigate how relative humidity (RH) affects the mechanical properties of electrospun polyvinylidene fluoride (PVDF). The mechanical properties of single fibers were carried out using a specialized tensile stage. The results from tensile tests were additionally correlated with high-resolution imaging showing the behavior of individual fibers under tensile stress. The mechanical characteristic is strongly dependent on the crystallinity, chain orientation, and fiber diameter of electrospun PVDF fibers. Our results show the importance of controlling RH during electrospinning as the mechanical properties are significantly affected. At low RH = 30% PVDF fibers are 400% stiffer than their counterparts prepared at high RH = 60%. Moreover, the vast differences in the strain at failure were observed, namely 310% compared to 75% for 60% and 30% RH, respectively. Our results prove that humidity is a crucial parameter in electrospinning able to control the mechanical properties of polymer fibers.

ACS Style

Piotr Szewczyk; Daniel Ura; Urszula Stachewicz. Humidity Controlled Mechanical Properties of Electrospun Polyvinylidene Fluoride (PVDF) Fibers. Fibers 2020, 8, 65 .

AMA Style

Piotr Szewczyk, Daniel Ura, Urszula Stachewicz. Humidity Controlled Mechanical Properties of Electrospun Polyvinylidene Fluoride (PVDF) Fibers. Fibers. 2020; 8 (10):65.

Chicago/Turabian Style

Piotr Szewczyk; Daniel Ura; Urszula Stachewicz. 2020. "Humidity Controlled Mechanical Properties of Electrospun Polyvinylidene Fluoride (PVDF) Fibers." Fibers 8, no. 10: 65.

Journal article
Published: 19 September 2020 in Materials
Reads 0
Downloads 0

Electric field strength and polarity in electrospinning processes and their effect on process dynamics and the physical properties of as-spun fibers is studied. Using a solution of the neutral polymer such as poly(methyl methacrylate) (PMMA) we explored the electrospun jet motion issued from a Taylor cone. We focused on the straight jet section up to the incipient stage of the bending instability and on the radius of the disk of the fibers deposited on the collecting electrode. A new correlation formula using dimensionless parameters was found, characterizing the effect of the electric field on the length of the straight jet, L˜E~E˜0.55. This correlation was found to be valid when the spinneret was either negatively or positively charged and the electrode grounded. The fiber deposition radius was found to be independent of the electric field strength and polarity. When the spinneret was negatively charged, L˜E was longer, the as-spun fibers were wider. The positively charged setup resulted in fibers with enhanced mechanical properties and higher crystallinity. This work demonstrates that often-overlooked electrical polarity and field strength parameters influence the dynamics of fiber electrospinning, which is crucial for designing polymer fiber properties and optimizing their collection.

ACS Style

Daniel P. Ura; Joan Rosell-Llompart; Angelika Zaszczyńska; Gleb Vasilyev; Arkadiusz Gradys; Piotr K. Szewczyk; Joanna Knapczyk-Korczak; Ron Avrahami; Alena O. Šišková; Arkadii Arinstein; Paweł Sajkiewicz; Eyal Zussman; Urszula Stachewicz. The Role of Electrical Polarity in Electrospinning and on the Mechanical and Structural Properties of As-Spun Fibers. Materials 2020, 13, 4169 .

AMA Style

Daniel P. Ura, Joan Rosell-Llompart, Angelika Zaszczyńska, Gleb Vasilyev, Arkadiusz Gradys, Piotr K. Szewczyk, Joanna Knapczyk-Korczak, Ron Avrahami, Alena O. Šišková, Arkadii Arinstein, Paweł Sajkiewicz, Eyal Zussman, Urszula Stachewicz. The Role of Electrical Polarity in Electrospinning and on the Mechanical and Structural Properties of As-Spun Fibers. Materials. 2020; 13 (18):4169.

Chicago/Turabian Style

Daniel P. Ura; Joan Rosell-Llompart; Angelika Zaszczyńska; Gleb Vasilyev; Arkadiusz Gradys; Piotr K. Szewczyk; Joanna Knapczyk-Korczak; Ron Avrahami; Alena O. Šišková; Arkadii Arinstein; Paweł Sajkiewicz; Eyal Zussman; Urszula Stachewicz. 2020. "The Role of Electrical Polarity in Electrospinning and on the Mechanical and Structural Properties of As-Spun Fibers." Materials 13, no. 18: 4169.

Research article
Published: 10 December 2019 in ACS Applied Materials & Interfaces
Reads 0
Downloads 0

Water is the basis of life in the world. Unfortunately, resources are shrinking at an alarming rate. The lack of access to water is still the biggest problem in the modern world. The key to solving it is to find new unconventional ways to obtain water from alternative sources. Fog collectors are becoming an increasingly important way of water harvesting as there are places in the world where fog is the only source of water. Our aim is to apply electrospun fiber technology, due to its high surface area, to increase fog collection efficiency. Therefore, composites consisting of hydrophobic and hydrophilic fibers were successfully fabricated using a two-nozzle electrospinning set up. This design enables the realization of optimal meshes for harvesting water from fog. In our studies we focused on combining hydrophobic, polystyrene (PS) and hydrophilic, polyamide 6 (PA6) surface properties in the produced meshes, without any chemical modifications, based on new hierarchical composites for collecting water. This combination of hydrophobic and hydrophilic material cause water to condense on the hydrophobic microfibers and to run down on the hydrophilic nanofibers. By adjusting the fraction of PA6 nanofibers we were able to tune the mechanical properties of PS meshes and importantly increase the efficiency in collecting water. We combined a few characterization methods together with novel image processing protocols for the analysis of fiber fractions in the constructed meshes. The obtained results show a new single-step method to produce meshes with enhanced mechanical properties and water collecting abilities that can be applied in existing Fog Water Collectors. This is a new promising design for fog collectors with nano- and macro- fibers which are able to efficiently harvest water, showing a great application in comparison to commercially available standard meshes.

ACS Style

Joanna Knapczyk-Korczak; Daniel Ura; Marcin Gajek; Mateusz Marek Marzec; Katarzyna Berent; Andrzej Bernasik; John Chiverton; Urszula Stachewicz. Fiber-Based Composite Meshes with Controlled Mechanical and Wetting Properties for Water Harvesting. ACS Applied Materials & Interfaces 2019, 12, 1665 -1676.

AMA Style

Joanna Knapczyk-Korczak, Daniel Ura, Marcin Gajek, Mateusz Marek Marzec, Katarzyna Berent, Andrzej Bernasik, John Chiverton, Urszula Stachewicz. Fiber-Based Composite Meshes with Controlled Mechanical and Wetting Properties for Water Harvesting. ACS Applied Materials & Interfaces. 2019; 12 (1):1665-1676.

Chicago/Turabian Style

Joanna Knapczyk-Korczak; Daniel Ura; Marcin Gajek; Mateusz Marek Marzec; Katarzyna Berent; Andrzej Bernasik; John Chiverton; Urszula Stachewicz. 2019. "Fiber-Based Composite Meshes with Controlled Mechanical and Wetting Properties for Water Harvesting." ACS Applied Materials & Interfaces 12, no. 1: 1665-1676.

Journal article
Published: 09 May 2019 in Bioengineering
Reads 0
Downloads 0

Tissue engineering requires properly selected geometry and surface properties of the scaffold, to promote in vitro tissue growth. In this study, we obtained three types of electrospun poly(methyl methacrylate) (PMMA) scaffolds-nanofibers, microfibers, and ribbons, as well as spin-coated films. Their morphology was imaged by scanning electron microscopy (SEM) and characterized by average surface roughness and water contact angle. PMMA films had a smooth surface with roughness, Ra below 0.3 µm and hydrophilic properties, whereas for the fibers and the ribbons, we observed increased hydrophobicity, with higher surface roughness and fiber diameter. For microfibers, we obtained the highest roughness of 7 µm, therefore, the contact angle was 140°. All PMMA samples were used for the in vitro cell culture study, to verify the cells integration with various designs of scaffolds. The detailed microscopy study revealed that higher surface roughness enhanced cells' attachment and their filopodia length. The 3D structure of PMMA microfibers with an average fiber diameter above 3.5 µm, exhibited the most favorable geometry for cells' ingrowth, whereas, for other structures we observed cells growth only on the surface. The study showed that electrospinning of various scaffolds geometry is able to control cells development that can be adjusted according to the tissue needs in the regeneration processes.

ACS Style

Daniel P. Ura; Joanna E. Karbowniczek; Piotr K. Szewczyk; Sara Metwally; Mateusz Kopyściański; Urszula Stachewicz. Cell Integration with Electrospun PMMA Nanofibers, Microfibers, Ribbons, and Films: A Microscopy Study. Bioengineering 2019, 6, 41 .

AMA Style

Daniel P. Ura, Joanna E. Karbowniczek, Piotr K. Szewczyk, Sara Metwally, Mateusz Kopyściański, Urszula Stachewicz. Cell Integration with Electrospun PMMA Nanofibers, Microfibers, Ribbons, and Films: A Microscopy Study. Bioengineering. 2019; 6 (2):41.

Chicago/Turabian Style

Daniel P. Ura; Joanna E. Karbowniczek; Piotr K. Szewczyk; Sara Metwally; Mateusz Kopyściański; Urszula Stachewicz. 2019. "Cell Integration with Electrospun PMMA Nanofibers, Microfibers, Ribbons, and Films: A Microscopy Study." Bioengineering 6, no. 2: 41.

Journal article
Published: 27 December 2018 in Polymers
Reads 0
Downloads 0

Wettability of electrospun fibers is one of the key parameters in the biomedical and filtration industry. Within this comprehensive study of contact angles on three-dimensional (3D) meshes made of electrospun fibers and films, from seven types of polymers, we clearly indicated the importance of roughness analysis. Surface chemistry was analyzed with X-ray photoelectron microscopy (XPS) and it showed no significant difference between fibers and films, confirming that the hydrophobic properties of the surfaces can be enhanced by just roughness without any chemical treatment. The surface geometry was determining factor in wetting contact angle analysis on electrospun meshes. We noted that it was very important how the geometry of electrospun surfaces was validated. The commonly used fiber diameter was not necessarily a convincing parameter unless it was correlated with the surface roughness or fraction of fibers or pores. Importantly, this study provides the guidelines to verify the surface free energy decrease with the fiber fraction for the meshes, to validate the changes in wetting contact angles. Eventually, the analysis suggested that meshes could maintain the entrapped air between fibers, decreasing surface free energies for polymers, which increased the contact angle for liquids with surface tension above the critical Wenzel level to maintain the Cassie-Baxter regime for hydrophobic surfaces.

ACS Style

Piotr K. Szewczyk; Daniel P. Ura; Sara Metwally; Joanna Knapczyk-Korczak; Marcin Gajek; Mateusz M. Marzec; Andrzej Bernasik; Urszula Stachewicz. Roughness and Fiber Fraction Dominated Wetting of Electrospun Fiber-Based Porous Meshes. Polymers 2018, 11, 34 .

AMA Style

Piotr K. Szewczyk, Daniel P. Ura, Sara Metwally, Joanna Knapczyk-Korczak, Marcin Gajek, Mateusz M. Marzec, Andrzej Bernasik, Urszula Stachewicz. Roughness and Fiber Fraction Dominated Wetting of Electrospun Fiber-Based Porous Meshes. Polymers. 2018; 11 (1):34.

Chicago/Turabian Style

Piotr K. Szewczyk; Daniel P. Ura; Sara Metwally; Joanna Knapczyk-Korczak; Marcin Gajek; Mateusz M. Marzec; Andrzej Bernasik; Urszula Stachewicz. 2018. "Roughness and Fiber Fraction Dominated Wetting of Electrospun Fiber-Based Porous Meshes." Polymers 11, no. 1: 34.

Journal article
Published: 11 December 2018 in Nano Energy
Reads 0
Downloads 0

Triboelectric generators rely on contact-generated surface charge transfer between materials with different electron affinities to convert mechanical energy into useful electricity. The ability to modify the surface chemistry of polymeric materials can therefore lead to significant enhancement of the triboelectric performance. Poly(methyl methacrylate) (PMMA) is a biocompatible polymer commonly used in medical applications, but its central position on the triboelectric series, which empirically ranks materials according to their electron-donating or electron accepting tendencies, renders it unsuitable for application in triboelectric generators. Here, we show that the surface potential of PMMA fibers produced by electrospinning can be tailored through the polarity of the voltage used during the fabrication process, thereby improving its triboelectric performance, as compared to typically spin-coated PMMA films. The change in surface chemistry of the electrospun PMMA fibers is verified using X-ray photoelectron spectroscopy, and this is directly correlated to the changes in surface potential observed by Kelvin probe force microscopy. We demonstrate the enhancement of triboelectric energy harvesting capability of the electrospun PMMA fibers, suggesting that this surface potential modification approach can be more widely applied to other materials as well, for improved triboelectric performance.

ACS Style

Tommaso Busolo; Daniel Ura; Sung Kyun Kim; Mateusz M. Marzec; Andrzej Bernasik; Urszula Stachewicz; Sohini Kar-Narayan. Surface potential tailoring of PMMA fibers by electrospinning for enhanced triboelectric performance. Nano Energy 2018, 57, 500 -506.

AMA Style

Tommaso Busolo, Daniel Ura, Sung Kyun Kim, Mateusz M. Marzec, Andrzej Bernasik, Urszula Stachewicz, Sohini Kar-Narayan. Surface potential tailoring of PMMA fibers by electrospinning for enhanced triboelectric performance. Nano Energy. 2018; 57 ():500-506.

Chicago/Turabian Style

Tommaso Busolo; Daniel Ura; Sung Kyun Kim; Mateusz M. Marzec; Andrzej Bernasik; Urszula Stachewicz; Sohini Kar-Narayan. 2018. "Surface potential tailoring of PMMA fibers by electrospinning for enhanced triboelectric performance." Nano Energy 57, no. : 500-506.

Short communication
Published: 04 September 2018 in Materials Letters
Reads 0
Downloads 0

In this study, we showed a simple approach to biomimic the wetting properties of spider webs, which can be mainly attributed to the geometry of fibers. We created biomimetic fibers using electrospun polyvinylidene fluoride (PVDF) with a wrinkled surface similar to the morphology of spider silk bundles produced by Linothele megatheloides. Without any chemical modification and copying the silk bundles geometry, we successfully translated the similar hydrophobic properties to an electrospun network of fibers. The novelty of this approach lays in obtaining similar macroscale roughness parameters, responsible here for wetting contact angles, due to the substitution of spider silk bundles with individual wrinkled electrospun fibers. The presented methods open new creative solutions for manufacturing anti-wetting surfaces.

ACS Style

Piotr K. Szewczyk; Joanna Knapczyk-Korczak; Daniel Ura; Sara Metwally; Adam Gruszczyński; Urszula Stachewicz. Biomimicking wetting properties of spider web from Linothele megatheloides with electrospun fibers. Materials Letters 2018, 233, 211 -214.

AMA Style

Piotr K. Szewczyk, Joanna Knapczyk-Korczak, Daniel Ura, Sara Metwally, Adam Gruszczyński, Urszula Stachewicz. Biomimicking wetting properties of spider web from Linothele megatheloides with electrospun fibers. Materials Letters. 2018; 233 ():211-214.

Chicago/Turabian Style

Piotr K. Szewczyk; Joanna Knapczyk-Korczak; Daniel Ura; Sara Metwally; Adam Gruszczyński; Urszula Stachewicz. 2018. "Biomimicking wetting properties of spider web from Linothele megatheloides with electrospun fibers." Materials Letters 233, no. : 211-214.