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1.
Materials (Basel) ; 16(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37109884

RESUMO

The use of modern materials in sports, in terms of chemical composition and surface texture, entails both progress in results and an increasing discrepancy in the technical parameters of the equipment used. This paper aims to demonstrate the differences between balls admitted to a league and world championships in composition, surface texture, and the influence of these parameters on the water polo game. This research compared two new balls produced by top companies producing sports accessories (Kap 7 and Mikasa). To obtain the goal, the measurement of the contact angle, analysis of the material using Fourier-transform infrared spectroscopy, and optical microscopic evaluation were used. The analysis of the surface free energy shows significant differences (Kap 7 32.16 mJ/m2, Mikasa 36.48 mJ/m2). In the case of both balls, anisotropies of the structure of the furrows were observed, however, the Mikasa ball is slightly more homogeneous than the Kap 7 ball. The obtained results from the analysis of the contact angle, as well as the composition and real feedback from the players, indicated the need to standardize the material aspect of the regulations so that the sports results are repeatable every time.

2.
Materials (Basel) ; 15(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35744221

RESUMO

The aim of the study was the qualitative assessment of new materials based on a polycarbonate matrix in terms of its use in 3D printing and its processing and geometric modification (cutting). Filaments made of the new material doped with talc in five different proportions were visually inspected with a microscope. The calibration and test models were made using the FFF (fused filament fabrication) technique. In addition, its susceptibility to the drill and the behavior of the shavings were assessed and the temperature changing during drilling was measured. The implant was inserted to measure its resonance stability in each of the holes made and translated into the value of the implant stability quotient (ISQ) ranging from 1 to 100. The results were compared to those obtained for the training model of the skull bone. The amount of filler has been shown to affect the composite. Moreover, due to the properties of talc, a compatibilizer (polyol) was used. Differences were observed between the model made of the commercial material, the model made of the dried, tested material, and the model made of the undried material. It was confirmed that the presence of water in the material during its processing is important.

3.
Materials (Basel) ; 15(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35591653

RESUMO

The main aim of the study was to synthesize and analyze spectral data to determine the structure and stereometry of the carbon-based porous material internal structure. Samples of a porous biomaterial were synthesized through anionic polymerization following our own patent and then carbonized. The samples were investigated using MALDI ToF MS, FTIR ATR spectroscopy, optic microscopy, SEM, confocal laser scanning microscopy and CMT imaging. The analysis revealed the chemical and stereological structure of the obtained porous biomaterial. Then, the parameters characterizing the pore geometry and the porosity of the samples were calculated. The developed material can be used to collect adsorption of breathing phase samples to determine the parity composition of exhaled air.

4.
Polymers (Basel) ; 13(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34685330

RESUMO

This research aimed to examine the mechanical properties of polycarbonate-based composites filled with both organic and inorganic reinforcements before and after simulated environmental degradation. Series of polycarbonate-based samples were prepared in the form of thin tapes. Their rheological properties were examined. Then, the samples were exposed to artificial environmental conditions. Finally, their rheological properties were examined once more, and the results were compared with those obtained for untreated samples. This paper presents basic research on the application of inorganic fillers to polycarbonate in order to determine the influence of the filler on the behavior of the obtained material. The aim of the work was to determine the usefulness and purpose of using this type of filler in polycarbonates for applications in contact with ultraviolet radiation, especially medical applications.

5.
Materials (Basel) ; 14(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34443247

RESUMO

In the era of modern medicine, the number of invasive treatments increases. Artificial devices used in medicine are associated with an increased risk of secondary infections. Bacterial biofilm development observed on the implanted surface is challenging to treat, primarily due to low antibiotics penetration. In our study, the preparation of a new polycarbonate composite, filled with nanosilver, nanosilica and rhodamine B derivative, suitable for three-dimensional printing, is described. Polymer materials with antimicrobial properties are known. However, in most cases, protection is limited to the outer layers only. The newly developed materials are protected in their entire volume. Moreover, the antibacterial properties are retained after multiple high-temperature processing were performed, allowing them to be used in 3D printing. Bacterial population reduction was observed, which gives an assumption for those materials to be clinically tested in the production of various medical devices and for the reduction of morbidity and mortality caused by multidrug-resistant bacteria.

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