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1
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Behavior of Fluoropolymers in Presence of Tritiated Water

100%
Bubueanu G., Postolache C., Fugaru V., Tuta C.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
1363-1366
EN
The behaviour of Polytetrafluoroethylene (PTFE), NAFION ionomer membranes and VITON fluoroelastomer in presence of high activity tritiated water (HTO) was analysed. Radiolytic stability of the fluoropolymers-HTO system was analysed by: (a) Simulation of radiolytic processes by quantum mechanical methods, (b) Simulation of radiolytic effects by exposure of fluoropolymers immersed in H₂O to ^{60}Co gamma radiation field, (c) Immersing of fluoropolymers samples in HTO with high activity, for different time periods. In both cases the samples were characterized by FT IR ATR, and study of emission of fluoride ions from polymer matrix.
2
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Modification of Optical and Electrical Properties of PET Foils by He⁺, Ne⁺ and Ar⁺ Implantation

51%
Droździel A., Turek M., Pyszniak K., Prucnal S., Luchowski R., Grudziński W., Klimek-Turek A., Partyka J.
Acta Physica Polonica A
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2017
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vol. 132
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issue 2
264-269
EN
Thin (3 μm) polyethylene terephthalate (PET) foils were irradiated with 135 keV He⁺, Ne⁺ and Ar⁺ ions with the fluences up to 5×10¹⁵ cm¯². Changes of chemical structure of the polymer were studied with the Fourier transform infrared and Raman spectroscopy - breaking of numerous chemical bonds, polymer chain cross-linking as well as formation of sp² hybridised carbon clusters and cluster networks were demonstrated. The increase of the implanted sample absorbance with the implantation fluence in the UV-VIS spectra as well as the decrease of optical band-gap energy (2.75 and 2.0 eV for He and Ne, respectively, at 5×10¹⁵ cm¯²) are observed. Decrease of bulk resistance of heavily treated samples by ≈5 orders of magnitude is determined. Measurements of the sheet resistance confirm that the sample becomes conducting also on the reverse (unimplanted) side of the foil. Both of these effects depend on the impinging ion mass - they are the strongest for Ar. The increase of both ac conductance and dielectric constant is observed in the frequency range up to 2 MHz and these changes rise with the impinging ion mass.
3
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Polymeric Track Etched Membranes - Application for Advanced Porous Structures Formation

51%
Sartowska B., Starosta W., Apel P., Orelovitch O., Blonskaya I.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
819-821
EN
Track etched membranes are porous systems consisting of a thin polymer foil with channels from surface to surface. Latent ion tracks are the result of the passage of swift ions through solid matter and they can be etched selectively. As a result, conical, cylindrical or other shape channels can be obtained. The increasing interest in the polymer track etched membranes with nanochannels is connected with development and creation of nanoporous materials of unique properties. The template synthesis method based on deposition of materials inside well-defined uniform pores of membranes offers unique possibilities of formation of one-dimensional, high aspect ratio (length to diameter) cylindrical species having form of rods, wires, tubules, multiwall tubules and multilayer rods, practically from any solid material. Metal-organic frameworks are a class of hybrid materials comprising metal ion-based vertices and organic ligands (linkers) which serve to connect the vertices into one-, two- or three-dimensional periodic structures. A specific property of porous structures is their intrinsic porosity, which renders them potentially useful for gas storage, separation and catalysis. The possibility of obtaining a new composite material: polymeric track etched membrane with pores filled with hybrid porous material has been demonstrated.
4
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Dielectric Relaxation in Hydrogen Bonded Urea-Based Supramolecular Polymer N,N'-di(2,2-dipentylheptyl)urea

51%
Jadżyn J., Bouteiller L., Déjardin J., Czechowski G.
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EN
Results of the dielectric relaxation studies, performed for supramolecular polymer formed by N,N'-di(2,2-dipentylheptyl)urea dissolved in carbon tetrachloride, are presented. The measurements were done for N,N'-di(2,2-dipentylheptyl)urea concentration up to about 7% (in mole fraction) in the frequency region from 100 kHz to 100 MHz and at the temperatures from 5ºC to 50ºC. The analysis of the experimental data were performed with the Havriliak-Negami equation. In the studied range of N,N'-di(2,2-dipentylheptyl)urea concentration and temperature, the obtained values of exponentsα andβ of the Havriliak-Negami equation are equal to 0.9±0.1 and 0.7±0.1, respectively, showing an anomaly in the dielectric relaxation behavior close to the Davidson-Cole type. Two examples of the modeling of dielectric properties of the supramolecular polymer solutions were presented.
5
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The Effect of Electron Irradiation on Polybutene-1 and Its Ethylene Copolymers

51%
Hribova M., Rybnikar F., Manas D.
Acta Physica Polonica A
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2012
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vol. 122
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issue 3
569-571
EN
The beta irradiation, as one of several possibilities how to modify the polymer properties resulted in isotactic polybutene-1 (PB-1) and its random copolymers with ethylene (E) mainly in chain scission without chain cross-linking. The original phase I did not change by irradiation, only the transformation rate of phase II to I increased with the irradiation dose and ethylene groups in PB-1/E copolymers. Beta irradiation decreased the sample crystallinity, crystal size, and perfection.
6
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Controlling of Optical Band Gap of Allyl Diglycol Carbonate Polymer with Ultraviolet Laser Radiation

51%
Farooq W., Baig M., Fatehmulla A., Al-Salhi M., Al-Ghamdi S., Yakuphanoglu F.
Acta Physica Polonica A
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2013
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vol. 123
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issue 1
106-110
EN
The effects of ultraviolet laser radiation on the structure and optical properties of allyl diglycol carbonate have been investigated. The allyl diglycol carbonate samples were irradiated with 266 nm with different power densities from Nd:YAG laser. The bulk etch rate enhancement and enlargement of track diameter clearly indicate that allyl diglycol carbonate is significantly affected by UV laser. The laser-irradiated allyl diglycol carbonate samples showed a decrease in the optical band gap with increasing laser power density. The obtained results indicate that the optical band gap of the alpha irradiated polymer is varied from 4.10 eV to 2.65 eV by UV laser irradiation.
7
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Sputtering of Benzene Sample by Large Ne, Ar and Kr Clusters - Molecular Dynamics Computer Simulations

45%
Rzeznik L., Paruch R., Garrison B., Postawa Z.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
825-827
EN
Molecular dynamics simulations are employed to probe the role of an impact angle on emission efficiency of organic molecules sputtered from benzene crystal bombarded by 15 keV Ne_{2953}, Ar_{2953}, and Kr_{2953} clusters. It is found that both the cluster type and the angle of incidence have significant effect on the emission efficiency. The shape of the impact angle dependence does not resemble the dependence characteristic for medium size clusters (C_{60}, Ar_{366}), where sputtering yield only moderately increases with the impact angle, has a shallow maximum around 40° and then decreases. On the contrary, for the large projectiles (Ne_{2953}, Ar_{2953}, and Kr_{2953}) the emission efficiency steeply increases with the impact angle, has a pronounced maximum around 55° followed by rapid signal decay. It has been found that the sputtering yield is the most sensitive to the impact angle change for Kr cluster projectiles, while change of the impact angle of Ne projectile has the smallest effect on the efficiency of material ejection.
8
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Content available

Studies of Fast Electron Irradiated Ferroelectric Poly(Vinylidene Fluoride)

45%
Goslar J., Hilczer B., Smogór H.
Acta Physica Polonica A
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2005
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vol. 108
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issue 1
89-94
EN
Radiation-induced functionalization of ferroelectric poly(vinylidene fluoride) was studied by ESR spectroscopy. The samples were irradiated in the high vacuum of a Van de Graaff accelerator with 1.0 MeV and 1.5 MeV electrons at room temperature and the decay of free radicals was studied after transferring the samples into the air. The samples exhibit a multicomponent ESR spectrum that can be decomposed into: a large asymmetric signal in the centre related to peroxy radicals, a quintet with hyperfine splitting A_F = 4.3 mT centred at g = 2.004, assigned to the in-chain radical (-CF_2-CH-CF_2-), and a triplet due to an end-chain (-CH_2) radical with A_H = 1.6 mT and g = 2.009.
9
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Fourier Transform Near Infrared Raman Spectroscopy in Studies on Connective Tissue

32%
Połomska M., Kubisz L., Kalawski R., Oszkinis G., Filipiak R., Mazurek A.
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issue 1
136-140
EN
Studies of tissue such as bones and veins often are carried out by means of microscopic and ultrasonographic methods. Therefore studies of changes caused by pathological or physical factors often are limited to morphological level. Application of Raman spectroscopy permits to associate morphological changes and molecular changes. The paper presents preliminary studies of temperature and ionizing radiation effects on Raman spectra of bone and collagen. Furthermore, effects of pathological factors on Raman spectra of human veins had been studied. It was noticed that heating of bone collagen up to 110°C gives the reversible changes in spectra. In the case of γ-irradiation, any effects were observed up to the dose of 1 MGy on mineral component of bone, whereas the influence on collagen was observed for doses higher than 100 kGy. The Raman spectra of varicose vs. normal veins permit to conclude some important changes observed for veins from chronic venous insufficiency patients.
10
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EPR Study of Gamma Irradiated Cholestanone Single Crystal

26%
Caliskan B.
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vol. 125
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issue 1
135-138
EN
Cholestanone (C_{27}H_{46}O) single crystals were irradiated with ^{60}Co-γ rays at room temperature. The spectra were recorded for different orientations of the crystal in the magnetic field at 120 K using the EPR technique. Radiation damage center was attributed to ĊHCH_2 CH_2 radical. The principal values of the hyperfine coupling tensor of the unpaired electron with the protons and the principal values of the g tensor were determined. The results were found to be in good agreement with the existing literature.
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