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The approach for ripple nanopattern construction on surface of two polymer substrates [polyethylene naphthalate (PEN) and polystyrene (PS)] exposed by a KrF pulse excimer UV laser through a contact lithographic mask with circular slit was proposed in this paper. Thin layer of gold was deposited on samples after the laser treatment. Changes in the morphology of the surface of both the shielded and exposed areas of the substrates, as well as the dimensions of the laser-induced periodic surface structures, were determined (by atomic force microscopy, laser confocal microscopy and scanning electron microscopy), compared with observations and measurements made on samples treated directly (without a contact mask) under the same conditions. The morphology of the interface between the treated and untreated regions was also closely studied. Surface chemistry of treated samples was studied in detail by X-ray Photoelectron Spectroscopy. The detailed study of surface chemistry of modified PEN and PS revealed a significant increase of oxygen concentration for laser treated PS and increase of carboxyl groups in case of PEN. The potential application of this research can be found in biotechnology, micro technology and several other fields. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work, we describe ripple and dot nanopatterning of three different aromatic polymer substrates by KrF excimer laser treatment. The conditions for regular structures were established by laser fluence and number of pulses. Subsequently, the influence of the angle of incidence of a laser beam was investigated. We have chosen polyethersulfone (PES), polyetherimide (PEI) and polyetheretherketone (PEEK) as substrates for modification since they are thermally, chemically and mechanically resistant aromatic polymers with high absorption coefficients at excimer laser wavelength. As a tool of wettability investigation, we used contact angle measurement and for determination of the absorption edge, UV–vis spectroscopy was used. Material surface chemistry was analyzed using FTIR and the changes caused by modification were gained as differential spectra by subtraction of the spectra of non-modified material. Surface morphology was investigated by atomic force microscopy, also the roughness and surface area of modified samples were studied. The scans showed the formation of regular periodic structures, ripples and dots, after treatment by 8 and 16 mJ cm −2 and 6000 pulses. Further, initial in vitro cytocompatibility tests were performed using U-2 OS cell line growing on PES samples subjected to scanning electron microscopy analysis. The structure formation mapping contributes strongly to development of new applications using nanostructured polymers, e.g. in tissue engineering or in combination with metallization in selected electronics and metamaterials construction. [ABSTRACT FROM AUTHOR]

The goal of this work was the investigation of the impact of two different excimer lasers on two biocompatible and biodegradable polymers (poly- l -lactide and poly hydroxybutyrate). Both polymers find usage in medical and pharmaceutical fields. The polymers were modified by KrF and ArF excimer lasers. Subsequently the impact on surface morphology, surface chemistry changes, and thermal properties was studied by means of confocal and AFM microscopy, FTIR and XPS spectroscopy and DSC calorimetry. Under the same conditions of laser treatment it was observed that ArF laser causes more significant changes on surface chemistry, surface morphology and pattern formation on the polymers under investigation. The data obtained in this work can be used for a wide range of possible applications, in tissue engineering or in combination with metallization in electronics, e.g. for biosensors. [ABSTRACT FROM AUTHOR]

In this paper, we describe laser modification of polyethersulphone films treated with polarized KrF laser under ablation threshold of PES. By this procedure the polymer can be modified under mild conditions and with low laser fluencies. Creation of surface ordered structure was observed already after application of 8 mJ cm −2 . Optimal conditions for nanodots and ripples formation were determined. Mechanism of surface ordered structure formation is attributed to enhancement of laser intensity due to propagation of surface waves which interfere with incoming beam. The wettability measurement confirmed increasing trend of surface contact angle with laser fluence. The threshold of laser fluence for morphology collapse was identified to be 20 mJ cm −2 . The metal nanolayer of 100 nm consequently deposited of the surface pattern proved to copy and enhance the morphological properties (ripple and dot formation). [ABSTRACT FROM AUTHOR]

Abstract: This paper is focused on characterization of surface properties of PMP (poly-4-methyl-1-pentene) after the modification of its upper layer. PMP is a thermoplastic polyolefine, which is used e.g. in medicine for its mechanical and thermal stability, for medical and laboratory equipment. Modification was carried out by Ar plasma, KrF excimer laser beam, thermal annealing and their combinations. The changes in physico-chemical properties of surface layer, such as wettability, ablation, morphology, roughness and chemical composition, were determined. Finally, the tests of adhesion and proliferation of cells were carried out on the selected samples. PMP seems a very resistant material, but plasma exposure can affect its surface properties, e.g. wettability or atomic concentrations of elements, which cause improvement of VSMC cells ability to adhere and proliferate. All used methods have just minor effect on morphology. Except under extreme conditions, a KrF excimer laser beam has only insignificant influence on PMP changes. Because of that, PMP could be suitable as a resistant carrier for materials for the further laser modification. [Copyright &y& Elsevier]

The study of excimer laser treatment of polystyrene surface was performed. The influence of laser fluence and number of laser pulses on surface chemistry and morphology was determined. The surface morphology and roughness were studied with atomic force microscopy. Surface wettability and aging studies were characterized by the water contact angle measurements. Surface oxygen concentration and chemistry were evaluated from X-ray photoelectron spectroscopy and zeta potential measurements. The optimal polystyrene treatment parameters for the most regular pattern were determined. The foils with optimal ripple pattern were subsequently sputtered with gold nano-layers of 100 nm thickness. It was found that the surface roughness of PS strongly depends on number of pulses. The aging study revealed that the higher contact angle achieve the samples treated with higher laser fluence. The deposition of gold nano-layer increases the surface roughness of nano-patterned surface. It was proved that the oxygen concentration is significantly influenced by the KrF laser exposure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Polyethylene naphthalate ripple pattern was successfully prepared. [•] Dimensions of nanostructures can be precisely controlled. [•] KrF excimer treatment significantly changes the PEN surface chemistry. [•] Electrically continuous gold nanopattern was constructed. [ABSTRACT FROM AUTHOR]

A new method for biopolymer poly-L-lactic-acid (PLLA) surface nanostructuring with surface plasmon resonance appearance is proposed. The motivation of this work is to determine optimal conditions for rough or flat biopolymer surface which may find broad application in tissue engineering as biocompatible carrier for various types of cell lines. A combination of plasma pre-treatment with consequent excimer laser exposure is proposed as a method for increasing the roughness of PLLA surface and changing its morphology. The focus of this paper is to determine morphology changes in combination with mass loss changes. The ablation loss and morphology of PLLA was induced by excimer laser exposure of plasma pre-treated PLLA with different laser fluencies and number of pulses. The combination of a certain input parameters of plasma pre-treatment together with laser exposure induces extensive physico-chemical changes (morphology, contact angle, optical properties) on polymer surface with dramatic roughness increase. Gravimetric studies have revealed an extensive polymer ablation after excimer laser application. The effect of surface plasmon resonance was observed in laser modified PLLA. Conditions for PLLA surface flattening are also proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Biopolymer ablation induced by excimer laser treatment has been determined. [•] Surface nanostructures of “star” shape were observed on PLLA. [•] Surface chemistry changes by excimer treatment were proposed. [•] Roughness changes due to laser treatment were described in detail. [Copyright &y& Elsevier]

Abstract: Interference effects can lead to the formation of ripple structures at laser-irradiated poly(ethylene terephthalate) surfaces. Poly(ethylene terephthalate) surface was irradiated with linearly polarized light of a pulsed 157nm laser. In a certain range of irradiation parameters, the irradiation resulted in the formation of coherent ripples patterns. The dimension of the pattern depends on the angle of the laser beam incidence. The surface morphology of the nano-patterned poly(ethylene terephthalate) was analyzed by atomic force microscopy and focused ion beam-scanning electron microscopy. Oxygen concentration in the modified polymer surface was studied by angular resolved X-ray induced photo-electron spectroscopy. Gold nano-layers were consecutively sputtered onto the laser irradiated poly(ethylene terephthalate) surfaces. The morphology of the sputtered gold nano-layers was investigated with atomic force microscopy too. We found that the morphology of the gold nano-layers changes and depends on the surface pattern of the laser irradiated poly(ethylene terephthalate). Formation of gold “nano-hills” is observed at the ridges of the ripple structures. The amount of oxygen together with the morphology of prepared polymer pattern may be the dominant factors controlling the gold layer growth. The present results are compared with those obtained earlier on PET irradiated with krypton fluoride laser. [Copyright &y& Elsevier]

[Display omitted] In this article, we present an application of single shot technique realized with high energy excimer laser on gold-carbon nanolayer preheated on polydimethylsiloxane substrate. The surface chemistry of pattern was examined with X-ray Photoelectron Spectroscopy (XPS) and Energy dispersive spectroscopy (EDS), while the surface morphology was studied with atomic force microscopy and scanning electron microscopy. Wettability changes were determined by contact angle measurement. We have been able to prepare area of 3 cm2 of homogeneously dispersed gold nanocluster with incorporated carbon particles by a single excimer laser shot by control of underlayer carbon thickness. The fabricated carbon-gold nanocomposites could be potentially applied for sensor development or as surface enhanced Raman Spectroscopy (SERS) substrates. [ABSTRACT FROM AUTHOR]