The Experts below are selected from a list of 1671 Experts worldwide ranked by ideXlab platform

J. F. Watts - One of the best experts on this subject based on the ideXlab platform.

  • The morphology and topography of polymer surfaces and interfaces exposed by ultra-low-angle Microtomy
    Journal of Materials Science, 2005
    Co-Authors: Steven J Hinder, C. Lowe, Jeffrey T Maxted, J. F. Watts
    Abstract:

    The ultra-low-angle Microtomy (ULAM) technique has been developed to impart a cross-sectional, ultra-low-angle taper through polymeric materials such as coatings and paints. ULAM employs a conventional rotary microtome in combination with high-precision, angled sectioning blocks to fabricate the ultra-low-angle tapers. Subsequent investigation of the tapers produced by ULAM may be used in conjunction with X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (ToF-SIMS), for compositional depth profiling or ‘buried’ interface analysis. Variation in the selection of the ULAM taper angle and/or the analysis interval size employed enables depth resolution at the nanometre or micrometre scales to be achieved. In the work described here scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been employed to investigate the morphology and topography of the surfaces resulting from the ULAM tapering process. It is demonstrated that a correctly mounted polymeric sample, sectioned with a sharp microtome knife, displays little perturbation of the resulting polymeric surface after ULAM processing. Additionally, SEM analysis of the interface region between a poly(vinylidene fluoride) (PVdF) topcoat and polyurethane (PU) primer exposed by ULAM processing reveals that the interface region between the two coatings possesses a well-defined boundary. No evidence of polymeric smearing across the interface is observed. XPS compositional depth profiling across a buried’ PVdF/PU interface, exposed by ULAM processing, is employed to demonstrate the utility of the ULAM technique.

  • Interface analysis and compositional depth profiling by XPS of polymer coatings prepared using ultra‐low‐angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of

  • interface analysis and compositional depth profiling by xps of polymer coatings prepared using ultra low angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of <0.05°, investigated by high-resolution XPS employing a 15 μm spot-size enables the interface region to be probed at a depth resolution of <20 nm. Depth profiling characterization by XPS of a polyamide powder coating with an organosilane adhesion promoter reveals a silicon concentration gradient within the cured polymer. This result demonstrates that the organosilane preferentially segregates to the surface regions of the cured polymer coating system.

Steven J Hinder - One of the best experts on this subject based on the ideXlab platform.

  • The morphology and topography of polymer surfaces and interfaces exposed by ultra-low-angle Microtomy
    Journal of Materials Science, 2005
    Co-Authors: Steven J Hinder, C. Lowe, Jeffrey T Maxted, J. F. Watts
    Abstract:

    The ultra-low-angle Microtomy (ULAM) technique has been developed to impart a cross-sectional, ultra-low-angle taper through polymeric materials such as coatings and paints. ULAM employs a conventional rotary microtome in combination with high-precision, angled sectioning blocks to fabricate the ultra-low-angle tapers. Subsequent investigation of the tapers produced by ULAM may be used in conjunction with X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (ToF-SIMS), for compositional depth profiling or ‘buried’ interface analysis. Variation in the selection of the ULAM taper angle and/or the analysis interval size employed enables depth resolution at the nanometre or micrometre scales to be achieved. In the work described here scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been employed to investigate the morphology and topography of the surfaces resulting from the ULAM tapering process. It is demonstrated that a correctly mounted polymeric sample, sectioned with a sharp microtome knife, displays little perturbation of the resulting polymeric surface after ULAM processing. Additionally, SEM analysis of the interface region between a poly(vinylidene fluoride) (PVdF) topcoat and polyurethane (PU) primer exposed by ULAM processing reveals that the interface region between the two coatings possesses a well-defined boundary. No evidence of polymeric smearing across the interface is observed. XPS compositional depth profiling across a buried’ PVdF/PU interface, exposed by ULAM processing, is employed to demonstrate the utility of the ULAM technique.

  • Interface analysis and compositional depth profiling by XPS of polymer coatings prepared using ultra‐low‐angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of

  • interface analysis and compositional depth profiling by xps of polymer coatings prepared using ultra low angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of <0.05°, investigated by high-resolution XPS employing a 15 μm spot-size enables the interface region to be probed at a depth resolution of <20 nm. Depth profiling characterization by XPS of a polyamide powder coating with an organosilane adhesion promoter reveals a silicon concentration gradient within the cured polymer. This result demonstrates that the organosilane preferentially segregates to the surface regions of the cured polymer coating system.

C. Lowe - One of the best experts on this subject based on the ideXlab platform.

  • The morphology and topography of polymer surfaces and interfaces exposed by ultra-low-angle Microtomy
    Journal of Materials Science, 2005
    Co-Authors: Steven J Hinder, C. Lowe, Jeffrey T Maxted, J. F. Watts
    Abstract:

    The ultra-low-angle Microtomy (ULAM) technique has been developed to impart a cross-sectional, ultra-low-angle taper through polymeric materials such as coatings and paints. ULAM employs a conventional rotary microtome in combination with high-precision, angled sectioning blocks to fabricate the ultra-low-angle tapers. Subsequent investigation of the tapers produced by ULAM may be used in conjunction with X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (ToF-SIMS), for compositional depth profiling or ‘buried’ interface analysis. Variation in the selection of the ULAM taper angle and/or the analysis interval size employed enables depth resolution at the nanometre or micrometre scales to be achieved. In the work described here scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been employed to investigate the morphology and topography of the surfaces resulting from the ULAM tapering process. It is demonstrated that a correctly mounted polymeric sample, sectioned with a sharp microtome knife, displays little perturbation of the resulting polymeric surface after ULAM processing. Additionally, SEM analysis of the interface region between a poly(vinylidene fluoride) (PVdF) topcoat and polyurethane (PU) primer exposed by ULAM processing reveals that the interface region between the two coatings possesses a well-defined boundary. No evidence of polymeric smearing across the interface is observed. XPS compositional depth profiling across a buried’ PVdF/PU interface, exposed by ULAM processing, is employed to demonstrate the utility of the ULAM technique.

  • Interface analysis and compositional depth profiling by XPS of polymer coatings prepared using ultra‐low‐angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of

  • interface analysis and compositional depth profiling by xps of polymer coatings prepared using ultra low angle Microtomy
    Surface and Interface Analysis, 2004
    Co-Authors: Steven J Hinder, J. F. Watts, C. Lowe
    Abstract:

    Conventional rotary Microtomy in combination with high-precision, ultra-low-angle sectioning blocks have been used to produce cross-sectional, ultra-low-angle tapers in polymeric coating systems. Tapered samples produced by ultra-low-angle Microtomy (ULAM) have been employed in the investigation of intercoat bonding interfaces in multilayer polymeric coatings and for the compositional depth profiling of polymer/polymer + additives systems. X-ray photoelectron spectroscopy (XPS) cross-sectional analysis of a poly(vinylidene difluoride) (PVdF) based topcoat and a poly(urethane) based primer interface exposed by ULAM processing indicates diffusion of fluorine-containing components of the PVdF topcoat formulation into the uppermost nanometres of the underlying poly(urethane) primer. It is demonstrated that a ULAM exposed, cross-sectional multilayer interface, with a taper of <0.05°, investigated by high-resolution XPS employing a 15 μm spot-size enables the interface region to be probed at a depth resolution of <20 nm. Depth profiling characterization by XPS of a polyamide powder coating with an organosilane adhesion promoter reveals a silicon concentration gradient within the cured polymer. This result demonstrates that the organosilane preferentially segregates to the surface regions of the cured polymer coating system.

David Stifter - One of the best experts on this subject based on the ideXlab platform.

  • Cryo ultra-low-angle Microtomy for XPS-depth profiling of organic coatings
    Analytical and bioanalytical chemistry, 2013
    Co-Authors: T. Greunz, B. Strauß, Stefan E. Schausberger, Bettina Heise, B. Jachs, David Stifter
    Abstract:

    In X-ray photoelectron spectroscopy (XPS) Ar+ ion sputtering is usually used for depth profiling. However, for such samples as organic coatings, this is not feasible because of degradation. Also, measurement of a depth profile on a conventionally prepared cross-section is not possible if, for example, sample thickness is below the smallest available measurement spot size of the XPS system. In our approach we used a rotary microtome to cut samples under a shallow tilting angle of 0.5° to obtain an extended cross-section suitable for XPS investigations. We also used liquid nitrogen cooling to ensure an exposed area of higher quality: topography measurements with a novel optical 3D microscope and by atomic force microscopy revealed the linearity of the inclined sections. With our cryo ultra-low-angle Microtomy (cryo-ULAM) preparation technique we were able to determine, by XPS, elemental and chemical gradients within a 25 μm thick polyester-based organic coating deposited on steel. The gradients were related to, for example, depletion of the crosslinking agent in the sub-surface region. Complementary reflection electron energy-loss spectroscopy measurements performed on the cryo-ULAM sections also support the findings obtained from the XPS depth profiles.

Junji Sugiyama - One of the best experts on this subject based on the ideXlab platform.

  • On the detachment of the gelatinous layer in tension wood fiber
    Journal of Wood Science, 2005
    Co-Authors: Bruno Clair, Bernard Thibaut, Junji Sugiyama
    Abstract:

    The detachment of the gelatinous layer (G-layer), often observed on microtome cross sections, has led some authors to believe that the G-layer cannot act as the driving force of longitudinal shrinkage in tension wood. The aim of this study was to observe the detachment of the G-layer along fibers. Green wood blocks were cut transversely into two samples. One sample was kept in water and the other was oven-dried. With one face being common to both samples, the detachment of the G-layer was studied on the same fibers. Observations were performed after blocking deformation by embedding. This revealed that the detachment of the G-layer is an effect produced by the act of cutting the transverse face of the wood block to be embedded. At distances greater than 100 µm from this primary surface of the sample, no detachment was observed. Drying shrinkage shows little or no effect on this detachment. The result seems to explain well why the detachment of the G-layer occurs during sectioning using conventional sliding Microtomy. These observations prove the adhesion of the G-layer in massive wood and confirm the active role of the G-layer in tension wood properties.

  • On the detachment of gelatinous layer in tension wood fiber
    Journal of Wood Science, 2005
    Co-Authors: Bruno Clair, Bernard Thibaut, Junji Sugiyama
    Abstract:

    The detachment of gelatinous layer (G-layer), often observed on microtome cross sections, leads some authors believe that G-layer cannot act as the driving force of longitudinal shrinkage in tension wood. The aim of this study was to observe the detachment of G-layer along fibres. Green wood block was cut transversely into two samples. One sample was kept in water and the other oven-dried. One face being common to both samples, detachment of G-layer has been studied on the same fibres. Observations have been performed after blocking deformation by embedding. It reveals that the detachment of G-layer is a cutting effect produced during the first making of the transverse face of the wood block to be embedded. After 100 µm far from this primary surface of the sample no detachment can be observed. Drying shrinkage does not affect or little this detachment. The result seems to explain well why the detachment of G-layer occurs during sectioning using a conventional sliding Microtomy. These observations prove the adhesion of G-layer in massive wood and confirm the active role of G-layer in tension wood properties.