Plasma polymer films were deposited from hexamethyldisiloxane (HMDSO), dichloro(methyl)phenylsila... more Plasma polymer films were deposited from hexamethyldisiloxane (HMDSO), dichloro(methyl)phenylsilane (DCMPS) and vinyltriethoxysilane (VTEO) on polished silicon wafers using a RF helical coupling deposition system. The composition of elements in the surface region (top 6–8 nm) of the deposited films was studied by X-ray-induced photoelectron spectroscopy (XPS) on an ADES 400 VG Scientific photoelectron spectrometer using MgKα (1253.6 eV) or AlKα
ABSTRACT The mechanical stability of nanoclusters embedded in nanocomposite coatings was investig... more ABSTRACT The mechanical stability of nanoclusters embedded in nanocomposite coatings was investigated by scratch and wear tests supported by atomic force microscopy using surface topography mode. Titanium and plasma polymer nanoclusters were deposited on planar substrates (glass, titanium) using a magnetron-based gas aggregation cluster source. The deposited clusters were overcoated with thin titanium film of different thicknesses to stabilize the position of the clusters in the nanocomposite coating. Nanotribological measurements were carried out to optimize the thickness of the overcoating film for sufficient interfacial adhesion of the cluster/film system.
... Proc. 841 (2005), p. 375. [2] WC Oliver and GM Pharr, J. Mater. Res. 7 (1992), p. 1564. ... S... more ... Proc. 841 (2005), p. 375. [2] WC Oliver and GM Pharr, J. Mater. Res. 7 (1992), p. 1564. ... Sci. Eng. A 423 (2006), p. 14. Article | PDF (371 K) | View Record in Scopus | Cited By in Scopus (10). [11] V. Cech, J. Studynka, B. Cechalova, J. Mistrik and J. Zemek, Surf. Coat. Technol. ...
ABSTRACT The way how to determine trap concentrations and discrete trap energy levels in insulato... more ABSTRACT The way how to determine trap concentrations and discrete trap energy levels in insulators and semiconductors from the experimental j(U) (current density-voltage) characteristic of one-carrier steady-state space-charge-limited currents measured at constant temperature is described. The procedure of the experimental j(U) characteristic evaluation is presented. The analysis of the trap parameter errors is carried out and the requirements for the accuracy of measurements are deduced.[Russian Text Ignored].
International Journal of Adhesion and Adhesives, 2005
Adhesion of plasma polymer films to planar glass substrates was analysed using a microscratch tes... more Adhesion of plasma polymer films to planar glass substrates was analysed using a microscratch tester and an optical polarizing microscope. Plasma-polymerized vinyltriethoxysilane was deposited by an RF helical coupling pulsed plasma system. Scratch data were correlated with stylus radius, loading rate, film thickness and the effective power used. Scratch tests under dry and wet conditions revealed that interfacial adhesion of
The development of high-performance polymer composites is tightly bound with the functional surfa... more The development of high-performance polymer composites is tightly bound with the functional surface modification of reinforcements. A new method, based on the principle of the fiber-bundle pull-out test, is proposed to analyze the interfacial properties between the long fibers in the form of a bundle and the polymer matrix. Specimen geometry and a test fixture were designed using finite element
... interlayers in glass fiber/polyester composites VLADIMIR CECH ∗ Institute of Materials Chemis... more ... interlayers in glass fiber/polyester composites VLADIMIR CECH ∗ Institute of Materials Chemistry, Brno University of Technology, Purkynova 118, CZ-612 00 Brno, Czech Republic Accepted 15 December 2006 ... 19. V. Chirila, G. Marginean and W. Brandl, Surf. Coat. Technol. ...
Linköping Electronic Press Workshop and Conference Collection
The development of high-performance polymer composites is tightly bound with the functional surfa... more The development of high-performance polymer composites is tightly bound with the functional surface modification of reinforcements. A new method, based on the principle of the fiber-bundle pull-out test, was used to analyze the interfacial properties between the long fibers in the form of a bundle and the polymer matrix. The pull-out test can be used for a relative comparison of different surface modifications if the bundle geometry is unknown. Glass fibers coated by plasma polymer films of tetravinylsilane were tested to determine the interfacial shear strength as a function of RF power and film thickness that was varied from 50 nm to 10 µm. SEM micrographs of pulled-out (debonded) fiber bundle were used to characterize adhesion at the interlayer/fiber and polymer/interlayer interfaces.
ABSTRACT Functional coatings constructed as bilayer or multilayer (10-layer) structures were depo... more ABSTRACT Functional coatings constructed as bilayer or multilayer (10-layer) structures were deposited from pure tetravinylsilane monomer or a mixture of monomer and oxygen gas using plasma-enhanced chemical vapor deposition. Selected deposition conditions were used to deposit a plasma polymer layer of A and B type, which differ markedly in chemical and physical properties. The thickness of individual layers in the layered structure was 0.1–0.9 µm with a total coating thickness of 1 µm. Spectroscopic ellipsometry enabled us to differentiate and analyze the individual layers in structured coatings.
... A Berkovich tip with a radius of curvature of about 50 nm was used. The Young's modu... more ... A Berkovich tip with a radius of curvature of about 50 nm was used. The Young's modulus and hardness of film were determined from unloaddisplacement curves measured at 10% of the film thickness [11] using the OliverPharr method [12]. ...
Plasma-polymerized films of vinyltriethoxysilane were deposited by plasma-enhanced chemical vapor... more Plasma-polymerized films of vinyltriethoxysilane were deposited by plasma-enhanced chemical vapor deposition using an RF (13.56 MHz) helical coupling plasma system operated in pulsed regime. An effective power was reduced using pulsed plasma in order to decrease the degree of cross-linking of plasma polymer, which resulted in a material of lower Young’s modulus. The Young's modulus and hardness of films increased
Properties of a three-dimensional interlayer formed between the reinforcement (fiber) and the mat... more Properties of a three-dimensional interlayer formed between the reinforcement (fiber) and the matrix are final properties of composite materials. It means that surface properties, chemistry of the coated fiber and the matrix play a very important role for achieving good adhesion (a primary factor for stress transfer from the matrix to the fiber) and strong bonding between the fiber and
Plasma polymer films were deposited from hexamethyldisiloxane (HMDSO), dichloro(methyl)phenylsila... more Plasma polymer films were deposited from hexamethyldisiloxane (HMDSO), dichloro(methyl)phenylsilane (DCMPS) and vinyltriethoxysilane (VTEO) on polished silicon wafers using a RF helical coupling deposition system. The composition of elements in the surface region (top 6–8 nm) of the deposited films was studied by X-ray-induced photoelectron spectroscopy (XPS) on an ADES 400 VG Scientific photoelectron spectrometer using MgKα (1253.6 eV) or AlKα
ABSTRACT The mechanical stability of nanoclusters embedded in nanocomposite coatings was investig... more ABSTRACT The mechanical stability of nanoclusters embedded in nanocomposite coatings was investigated by scratch and wear tests supported by atomic force microscopy using surface topography mode. Titanium and plasma polymer nanoclusters were deposited on planar substrates (glass, titanium) using a magnetron-based gas aggregation cluster source. The deposited clusters were overcoated with thin titanium film of different thicknesses to stabilize the position of the clusters in the nanocomposite coating. Nanotribological measurements were carried out to optimize the thickness of the overcoating film for sufficient interfacial adhesion of the cluster/film system.
... Proc. 841 (2005), p. 375. [2] WC Oliver and GM Pharr, J. Mater. Res. 7 (1992), p. 1564. ... S... more ... Proc. 841 (2005), p. 375. [2] WC Oliver and GM Pharr, J. Mater. Res. 7 (1992), p. 1564. ... Sci. Eng. A 423 (2006), p. 14. Article | PDF (371 K) | View Record in Scopus | Cited By in Scopus (10). [11] V. Cech, J. Studynka, B. Cechalova, J. Mistrik and J. Zemek, Surf. Coat. Technol. ...
ABSTRACT The way how to determine trap concentrations and discrete trap energy levels in insulato... more ABSTRACT The way how to determine trap concentrations and discrete trap energy levels in insulators and semiconductors from the experimental j(U) (current density-voltage) characteristic of one-carrier steady-state space-charge-limited currents measured at constant temperature is described. The procedure of the experimental j(U) characteristic evaluation is presented. The analysis of the trap parameter errors is carried out and the requirements for the accuracy of measurements are deduced.[Russian Text Ignored].
International Journal of Adhesion and Adhesives, 2005
Adhesion of plasma polymer films to planar glass substrates was analysed using a microscratch tes... more Adhesion of plasma polymer films to planar glass substrates was analysed using a microscratch tester and an optical polarizing microscope. Plasma-polymerized vinyltriethoxysilane was deposited by an RF helical coupling pulsed plasma system. Scratch data were correlated with stylus radius, loading rate, film thickness and the effective power used. Scratch tests under dry and wet conditions revealed that interfacial adhesion of
The development of high-performance polymer composites is tightly bound with the functional surfa... more The development of high-performance polymer composites is tightly bound with the functional surface modification of reinforcements. A new method, based on the principle of the fiber-bundle pull-out test, is proposed to analyze the interfacial properties between the long fibers in the form of a bundle and the polymer matrix. Specimen geometry and a test fixture were designed using finite element
... interlayers in glass fiber/polyester composites VLADIMIR CECH ∗ Institute of Materials Chemis... more ... interlayers in glass fiber/polyester composites VLADIMIR CECH ∗ Institute of Materials Chemistry, Brno University of Technology, Purkynova 118, CZ-612 00 Brno, Czech Republic Accepted 15 December 2006 ... 19. V. Chirila, G. Marginean and W. Brandl, Surf. Coat. Technol. ...
Linköping Electronic Press Workshop and Conference Collection
The development of high-performance polymer composites is tightly bound with the functional surfa... more The development of high-performance polymer composites is tightly bound with the functional surface modification of reinforcements. A new method, based on the principle of the fiber-bundle pull-out test, was used to analyze the interfacial properties between the long fibers in the form of a bundle and the polymer matrix. The pull-out test can be used for a relative comparison of different surface modifications if the bundle geometry is unknown. Glass fibers coated by plasma polymer films of tetravinylsilane were tested to determine the interfacial shear strength as a function of RF power and film thickness that was varied from 50 nm to 10 µm. SEM micrographs of pulled-out (debonded) fiber bundle were used to characterize adhesion at the interlayer/fiber and polymer/interlayer interfaces.
ABSTRACT Functional coatings constructed as bilayer or multilayer (10-layer) structures were depo... more ABSTRACT Functional coatings constructed as bilayer or multilayer (10-layer) structures were deposited from pure tetravinylsilane monomer or a mixture of monomer and oxygen gas using plasma-enhanced chemical vapor deposition. Selected deposition conditions were used to deposit a plasma polymer layer of A and B type, which differ markedly in chemical and physical properties. The thickness of individual layers in the layered structure was 0.1–0.9 µm with a total coating thickness of 1 µm. Spectroscopic ellipsometry enabled us to differentiate and analyze the individual layers in structured coatings.
... A Berkovich tip with a radius of curvature of about 50 nm was used. The Young's modu... more ... A Berkovich tip with a radius of curvature of about 50 nm was used. The Young's modulus and hardness of film were determined from unloaddisplacement curves measured at 10% of the film thickness [11] using the OliverPharr method [12]. ...
Plasma-polymerized films of vinyltriethoxysilane were deposited by plasma-enhanced chemical vapor... more Plasma-polymerized films of vinyltriethoxysilane were deposited by plasma-enhanced chemical vapor deposition using an RF (13.56 MHz) helical coupling plasma system operated in pulsed regime. An effective power was reduced using pulsed plasma in order to decrease the degree of cross-linking of plasma polymer, which resulted in a material of lower Young’s modulus. The Young's modulus and hardness of films increased
Properties of a three-dimensional interlayer formed between the reinforcement (fiber) and the mat... more Properties of a three-dimensional interlayer formed between the reinforcement (fiber) and the matrix are final properties of composite materials. It means that surface properties, chemistry of the coated fiber and the matrix play a very important role for achieving good adhesion (a primary factor for stress transfer from the matrix to the fiber) and strong bonding between the fiber and
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