bluuebunny/crossref_metadata_2025_split huggingface dataset:
AES investigations of local inhomogeneities in aluminium oxide films on Fe‐based alloys
Authors: Oswald S. , John A. , Quadakkers W. J. 
Published: May 2005

AbstractAluminium oxide layers grown during high‐temperature oxidation on Fe‐based alloys have been investigated by lateral high‐resolution Auger electron spectroscopy. Comparison of the results with depth profiles measured by secondary ion mass spectrometry shows that the distribution of minor elements is connected with the formation of local inhomogeneities in the oxide layers. These properties are different depending on minor element concentration and manufacturing conditions of the materials.
SIMS analysis of Al δ‐doped GaAs test structures using chemical bevelling as a sample preparation technique
Authors: Hsu C. M. , Sharma V. K. M. , Ashwin M. J. , McPhail D. S. 
Published: May 2005

AbstractA chemical bevelling technique has been developed to synthesize high‐magnification bevels in gallium arsenide for SIMS linescanning and imaging. Bevels have been prepared in gallium arsenide substrate material, in gallium arsenide implanted with aluminium and in two delta‐doped (aluminium) GaAs test structures. The accuracy, sensitivity, dynamic range and depth resolution–depth characteristics of the bevel and linescan approach have been compared to conventional SIMS depth profiling. Images of the bevelled structures have been used to obtain a quick view of the features of interest. Linescans have yielded an aluminium profile from the aluminium implant that is very similar to that from a SIMS depth profile. Linescan results from the aluminium deltas in gallium arsenide indicate that depth resolutions of a few nanometers can be retained to depths of several microns. The depth resolution of the deltas has been measured as a function of bevel magnification and a theory has been developed to explain the results. A peak width (resolution) of 2.2 nm for an aluminium delta has been achieved at a bevel magnification of 6000 using a 15 keV 16O2+ ion beam, and a depth resolution limit of 1.3 nm has been deduced by extrapolation to infinite bevel magnification. The combined effects of beam‐induced mixing, microtopography and the escape depth of the secondary ions is a broadening of 2.0 nm for these conditions.
Static SIMS study of hydroxylation of low‐surface‐area silica
Authors: Wood B. J. , Lamb R. N. , Raston C. L. 
Published: May 2005

AbstractRelative surface silanol (SiOH) concentration levels on low‐surface‐area crystalline silica (synthetic quartz crystal) have been determined using the static secondary ion mass spectroscopy (SIMS) technique. Various sample pretreatments, including water plasma (maximum silanol/hydroxylation), heating in a vacuum to ∼550°C, heating in a vacuum to > 1000°C (minimum silano/hydroxylation) and inert gas ion bombardment in ultrahigh vacuum (UHV), are examined. Both positive ion ration (SiOH+/SiO+, SiOH+/Si+) and a negative ion ratio (OH−/O−) were monitored as a function of temperature as the pretreated surface dehydroxylated (increasing temperature) and rehydroxylated (decreasing temperature) in the UHV analysis chamber. Plots of positive ion and negative ion ratios for all data at the various stages of hydroxylation indicated a linear relationship. Deviations from this were attributed to the presence of physisorbed water and/or surface hydrocarbon contamination.
Study of electron backscattering within the approximation of discrete flows
Authors: Borodyansky S. , Tougaard S. 
Published: May 2005

AbstractThe path length distribution function (PLDF) for backscattered electrons was calculated within the four‐flow approximation. The problem was solved by using the invariant‐embedding approach. It was shown that the PLDF is very sensitive to the variation of the parameter describing the elastic scattering cross‐section's anisotropy.Methods of calculation of a probability of elastic electron backscattering and methods of reflection energy‐loss spectroscopy processing for calculating the electron differential inelastic scattering cross‐section are also discussed.
Analytical background correction in numerical Fourier transform procedures. Application to electron spectroscopy
Authors: Aminov K. L. , Pedersen J. Boiden 
Published: May 2005

AbstractAn analytical correction method is proposed to eliminate the problems resulting from numerical Fourier transformation of functions with a broad background. The method incorporates the analytically known or observed asymptotic behaviour into the numerical procedure. The applicability and high accuracy of the background correction method is illustrated by application to the analysis of reflected electron energy‐loss spectra.
Efficient calculation of photoelectron angular distribution
Authors: Werner Wolfgang S. M. , Tilinin Igor S. , Jablonski Aleksander 
Published: May 2005

AbstractDifferent methods of calculating efficiently the angular distribution of photoelectrons escaping from uniform amorphous and polycrystalline targets are analysed in detail. Comparison has been made between the analytical results and Monte Carlo simulation data. The analytical approach is based on the solution of the kinetic equation in the transport approximation. The Monte Carlo codes comprise the conventional forward simulation algorithm and the reverse trajectory method. The reverse trajectory method employs the reciprocity theorem and allows same statistically significant results to be obtained with less computational effort. The angular distributions of photoelectrons leaving Al, Si, Cu, Ag, Ta and Au samples have been calculated as a function of polar and azimuthal angles for electron energies relevant in quantitative XPS analysis. It has been found that both Monte Carlo methods provide equivalent results. The discrepancies between the transport approximation and the Monte Carlo data do not exceed, as a rule, 5%. The largest deviations of the analytical results from those found by Monte Carlo codes are observed in the vicinity of the emission directions, where the photoelectric differential cross‐section has its minima, and are about 15%. The agreement between the results obtained by different approaches, corresponding to the magic angle geometry, is within 2% for all cases studied.
Effect of PVC resins on multi‐screw pipe extrusion
Authors: Weiler Robert G. 
Published: May 2005

AbstractThe increased use of multi‐screw (twin) extruders by pipe producers brought on this study of available PVC homopolymer “pipe grade” resins. Basic tests on resin were examined via a “Correlation Matrix” computer program. Highly significant test data were determined to be internal pore volume and centrifuge plasticizer adsorption. Additional compound evaluation proceeded via torque rheometer followed by twin‐screw extrusion. Significant resin test values affecting extrusion properties are inherent viscosity, apparent bulk density, porosity uniformity and melt viscosity. The work shows that the compounder should know resin properties in order to benefit from processing equipment developments.
Developing low temperature, impact‐resistant PVC—a new testing approach
Authors: Goldman Theodore D. , Lutz John T. 
Published: May 2005

AbstractConcern over making end‐use predictions from milled/notched Izod test data for applications where product manufacturing techniques differ greatly from Izod test sample preparation brought on this study of the use of Gardner‐type impact tests on commercial and laboratory extruded PVC sheet. By notching the test sample, the standard Gardner and Izod impact tests at low temperatures could be predicted at room temperature in the Gardner test equipment.
Energy and material cost savings with polyester/monomeric plasticized PVC compounds
Authors: Bender M. H. , Lutz J. T. 
Published: May 2005

AbstractMany plasticized PVC articles are exposed to harsh environments that cause loss of plasticizer through extraction, volatility, or migration. In order to survive in these applications, the PVC must contain plasticizers that have a reasonable degree of permanence. Two approaches are the use of low molecular weight polyester plasticizers, or higher molecular weight polyester/monomeric plasticizer blends. The blend approach can give better cost‐performance and, due to faster fusion, reduced energy/manufacturing costs. The blends maintain their advantages even upon further dilution with monomeric plasticizers and in permanence tests of long duration. Although better than monomeric plasticizers, neither the low molecular weight polyester nor the blend system is recommended for applications requiring the ultimate in migration resistance.
Electrical behavior of poly(vinyl chloride): Wien‐Onsager effect deviations from Ohm's law
Authors: Wingrave James A. 
Published: May 2005

AbstractAn examination of electrolyte conduction in solid PVC plaques shows an enhancement in equivalent conductance in excess of that predicted by Onsager's theory of electrolyte conduction even when ion activity effects are considered. Although Onsager's theory includes Wien effect behavior, the experimental equivalent conductances were significantly in excess of the predicted values. From an examination of electrolyte conduction theory, several unique features of electrolyte flow in PVC are found which are not observed for liquid dielectrics. Based on these concepts, a qualitative explanation based on Onsager's original theory is proposed. The observed behavior is referred to as a Wien‐Onsager effect.
Ways of poly (vinyl chloride) stabilization
Authors: Minsker K. S. , Kolesov S. V. , Zaikov G. E. 
Published: May 2005

AbstractMain results of research on poly (vinyl chloride) (PVC) stabilization are discussed. Stabilization is viewed from the standpoint of the modern notions of the reasons for PVC low thermal stability, the complicated nature of its dehydrochlorination, and the kinetics of its degradation. The internal unsaturated oxygen‐containing groups of ∼C(O)CHCHCHCl∼ type are regarded as the main source of the polymer instability. Typical processes resulting in PVC stabilization, such as the substitution of labile chlorine atoms and the destruction of initial active sites during reactions with various chemical agents, as well as the kinetic aspects of stabilizers' effect on HCl elimination and PVC macromolecules crosslinkage are considered. The influence of additives on the polymer coloration is estimated.
Flow behavior of PVC in hot‐die‐face pelletizing: Die hole pattern optimization
Authors: Campbell Gary A. 
Published: May 2005

AbstractDie hole pattern optimization can minimize the pressure loss across the die plate for a given set of products, while maintaining sufficient steel strength. Data will be presented from a high‐pressure capillary rheometer to establish flow behavior and investigate the effects of die geometry on flow resistance. The influence of formulation parameters, degree of gelation and shear gradient will be considered. Finally a model will be developed for the optimization of the die hole pattern. Using this procedure, it will be possible to establish the data needed for optimal die hole pattern design by calculation and graphic presentation.
Behavior of plasticizers in poly (vinyl chloride) resins. I. A method for measuring dynamic plasticizer absorption in suspension resin grains
Authors: Wingrave James A. 
Published: May 2005

AbstractAn instrument which measures the absorption of plasticizer in resin grains as a function of time is described. From a single experiment, one is able to determine directly the capacity of the resin for a desired plasticizer and the time and temperature required for complete absorption or “drying‐up” of the plasticizer by the resin. Based on data for a series of resins with different polymerization histories, observations regarding the effects of grain morphology on plasticizer absorption are discussed.
Air release in PVC plastisols
Authors: Defife J. R. 
Published: May 2005

AbstractThe ability of a PVC plastisol to liberate entrapped air during mixing and processing is an important factor to the processors. This property, known as air release, is affected by several variables such as resin, plastisol viscosity, surface tension, surfactant system and plasticizer type. A study was conducted to obtain a more fundamental understanding of the effects of these variables on air release. Complicating the accurate study of a plastisol's air release properties is the fact that current test procedures such as the vacuum rise, syringe test and Huff or ring test each have limitations imposed by either plastisol properties or by testing technique. Any one of these procedures alone may not adequately measure air release. This paper, in addition to studying the factors affecting air release, discusses these testing limitations and makes recommendations as to the best methods for evaluating air release properties in the laboratory.
Low smoke, non‐contaminating speciality compounds
Authors: Varenelli Andrew D. , Weintraub Lester , Pearson Stanley 
Published: May 2005

AbstractA proprietary polymer has been used to create a variety of compounds. Of particular interest are a series of compounds which are flame resistant, generate low smoke, are non‐contaminating, and which exhibit excellent oven aging characteristics without impairment of low temperature flexibility. The paper will discuss the properties of the polymer and the properties of the various compositions which make them suitable for many applications such as wire and cable, film and sheet, medical, automotive, shoe soles and appliances.
Injection molding of PVC—today and tomorrow
Authors: McNally William J. 
Published: May 2005

AbstractInjection molding of PVC has been considered quite difficult because of the apparent low thermal stability with a high viscosity. While other materials were benefited by improved molding technology, technology applied to the molding of PVC received little attention. Whereas injection molding of PVC has been limited to general purpose pipe fittings, new resin technology and formulations provide compounds with excellent flow, easy molding characteristics and a good balance of physical properties.
Factors affecting the carbon dioxide barrier of vinylidene chloride‐vinyl chloride copolymer films
Authors: Delassus Phillip T. 
Published: May 2005

AbstractCopolymers of vinylidene chloride can be fabricated into films that have excellent barriers to carbon‐dioxide transparent. To retain the maximum barrier, liquid additives should not be used. Since the carbon dioxide barrier properties of different polymers have different temperature sensitivities, you must compare properties at the temperature of intended use.
Gel phenomena in flexible PVC resin
Authors: Zabrecky Judy E. 
Published: May 2005

AbstractThe existence of fisheyes or gels in PVC final products has been a problem which the PVC industry has coped with for many years. The classical gel is a non‐porous PVC particle which cannot absorb plasticizer. Other finished product defects which may be classified as gels by a customer are unfused particles of higher molecular weight resin or resin gels and agglomerates caused by improper mixing procedures called compound gels. Although this paper will define and cite examples of resin gels and compound gels, it will deal primarily with classical gel. Over the years, many different gel tests have been used by PVC suppliers and consumers in order to define the gel level of a particular sample of resin. The most common of these tests is the test using a two roll mill to produce a colored mill sheet which is examined and the number of gels reported. This paper will use statistical methods to the factors which can introduce variability into the test results, including mill roll gap, mill speed, milling time, and temperature. In addition, the nature of the distribution of gels in a sample of PVC resin will be discussed. Finally, the paper will delve into new laboratory techniques which may lead to eventual automation of counting and reporting of gel levels in a resin sample.
PVC compounds for photochemical crosslinking
Authors: Drexler Jiří , Maláč Jiří , Rektoříková Libuše , Šimoník Josef 
Published: May 2005

AbstractThe best of all photoinitiator systems for crosslinking PVC compounds, according to tests made with a Tesla RVIM discharge tube, is the combination of chlorthioxanthone and triethanolamine. Pentaerithroltriacrylate is the most effective crosslinking agent. Lead stabilizers give the best heat stability and a higher rate of photochemical crosslinking than tin and antimony stabilizers.
Effects of plasticizer desorption, temperature, and pressure on the permeability of saran
Authors: Chen J. S. , McCarthy S. P. 
Published: May 2005

AbstractWork has shown that (1) the permeability of saran film increases exponentially with increasing temperature due to activation energy, (2) permeability of saran film decreases slightly with increasing pressure–but to only a very slight extent, (3) microwave radiation does not affect permeability as long as the film is not heated during treatment, and (4) low amounts of liquid additives correlate with lower permeability. It is suggested that the barrier property of saran film can be improved without sacrificing the processing ability.
Rigid PVC: New developments for improving weatherability
Authors: Conroy Gary M. , Wursthorn K. R. 
Published: May 2005

AbstractPolyvinyl chloride is rapidly becoming recognized as a versatile polymer. It has a unique ability to accept additives, and the properties of the finished article often depend more on formulation than the resin itself.A wide variety of chemical may function similary in PVC, yet processors often have to compromise in selecting one additive over another. For example, both tin mercaptides and metal carboxylates function as thermal stabilizers. The mercaptide is superior as a thermal stabilizer while the carboxylate offers better weathering stability. Today's market tends to compromise at the expense of weathering. To compensate, high levels of reflective pigments (TiO2) are used.Recently, we initiated a research program and discovered a class of compounds which provide excellent weatherability with processability comparable to the highly‐efficient tin mercaptide. This cost‐effective development allows reduction of TiO2 levels by 25–50%. In addition, dark pigmented profiles remain relatively undeveloped because of serious weathering problems. Accelerated weathering and outdoor exposure tests demonstrate this technology is quite effective for UV stabilization of dark brown systems.
Strain‐induced crystallization kinetics of vinylidene chloride/vinyl chloride (VDC/VC) copolymers
Authors: Lund Monty , Remenar Richard , Burt Ed 
Published: May 2005

AbstractThe strain‐induced crystallization (SIC) behavior of VDC/VC copolymers has a significant effect on processibility on the blown film process. However, data on SIC of VCD/VC copolymers has been very limited due to the difficulty of measuring the rapid crystallization rates induced by strain; whereas, crystallization under quiescent conditions has been studied extensively. In this work, SIC of VDC/VC copolymers has been calculated from measurements of the adiabatic temperature rise upon stretching of amorphous specimens. The effect of stretching conditions such as strain rate, total strain, and initial temperature and the effect of polymer variables such as copolymer composition, molecular weight, and plasticizer content are determined. It is found that the performance of different VDC/VC copolymers on the film‐blowing process correlates much better with measurements of SIC than with quiescent crystallization behavior.
Application of the UNIFAC‐FV group contribution method to the prediction of relative compatibility of plasticizers with PVC
Authors: Boo Hwee‐Khim , Shaw Montgomery T. 
Published: May 2005

AbstractThe applicability of a modified version of UNIFAC group contribution method, UNIFAC‐FV, is explored for use in predicting liquid‐liquid equilibrium behavior of plasticizer/PVC systems. A Fortran program for the UNIFAC‐FV model has been written to calculate the activities and changes in the Gibbs free energy for multicomponent systems. By this means, the interaction parameter X for a polymer‐solvent system is defined using the well known Flory‐Huggins equation. The concentration dependent Gibbs free energy of mixing is used as a criterion for the relative compatibility of the PVC‐plasticizer system. The method indicates that, for the plasticizers examined, DOS is the least compatible and DBP is the most compatible with PVC. This confirms the results of the glass transition width measured by dynamic mechanical analysis previously reported.
Multiphase PVC/styrenic copolymer alloys: Internally reinforced by partial miscibility
Authors: Bourland L. G. 
Published: May 2005

AbstractAlthough polymer/polymer miscibility is considered the exception to the general rule, in polymer thermodynamics specific interactions between active sites on two polymers can be a driving force for polymer/polymer miscibility. Both the intermolecular interactions of the alpha hydrogen of PVC with carbonyl groups in various polyesters and the polarity of the chlorine bond have been claimed to promote miscibility. Both of these interactions are potential in PVC/styrene maleic anhydride (SMAnh) polymer blends. These specific interactions promoting miscibility and the resulting mechanical properties of these systems is the subject of this report. SMAnh (12.5% MA) copolymer was melt compounded with a stabilized PVC compound using a Haake Rheocord twin screw extruder. Test data generated for these blends were analyzed for miscibility and effects of SMAnh copolymers on heat resistance, fire retardance, impact strength, and processability of PVC.
Shrinkage in rigid PVC profile extrusions
Authors: Rabinovitch E. B. , Quisenberry J. G. 
Published: May 2005

AbstractShrinkage in PVC profile extrusions may have an effect on the end use performance (dimensional stability, mechanical properties) of the building products such as house siding and windows when they are heated by the sun. This paper examines the heat shrinkage tests being used in the industry, and most importantly, describes effects of the extrusion conditions such as melt temperature, shear rate, percent drawdown, and other variables on shrinkage in PVC profiles.
Effect of degree of ethoxilation on the viscosity depressancy properties of fatty acid ethoxilates used in PVC paste formulations
Authors: Düzgören M. , Bilgic T. , Savaşçi Ö. Tunç; 
Published: May 2005

AbstractPlastisols of poly (vinylchloride) (PVC) are important commercial products. The rheological properties especially the viscosity of the paste plays an important role in PVC paste applications. Viscosity depressants are usually added to paste formulations in order to obtain desired paste viscosities. In this work, viscosity depressant effects of various fatty acid/ethylene oxide condensates containing 2 to 12 moles ethylene oxide per mole are investigated by Brookfield rotational viscometric method. The effectivenesses of the viscosity depressants are determined at 1.3 sec−1 shear rates and a relationship between ethylene oxide content and viscosity reduction is found. This relationship between effectiveness and degree of ethoxilation gives way to prediction of viscosity reduction of paste by simply determining the ethylene oxide content. The effect on 24 h aging is also studied. The results showed improvements in short term aging properties of the PVC paste.