bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composites of polyvinyl chloride—wood fibers: IV. Effect of the nature of fibers
Authors: Maldas D. , Kokta B. V. , Daneault C. 
Published: May 2005

AbstractThe suitability of different pulps (e.g. chemithermomechanical, kraft, tempure, temalfa, cotton, and sawdust) as well as various wood species (e.g. softwood, spruce; hardwood, aspen and birch) as the reinforcing filler for thermoplastic composites of PVC (two different grades) have been evaluated on the basis of mechanical properties. Mechanical properties of the non‐treated composites were improved by the addition of a coupling agent [poly (methylene (polyphenyl isocyanate))] either in pure state or in solution, and by the pre‐treatment of the fibers by encapsulation. The order of reactivity of the pulps varies widely with the change in the grades of thermoplastics and the quality of treatment. Due to the interference of properties of the pulps in the composites, the relative reactivity changes.
Comparative effect of plasticizer interchange on flexible PVC processing as measured by a torque rheometer
Authors: Bergado Simo T. 
Published: May 2005

AbstractPresent testing methods of comparing dryblend and fusion characteristics of poly (vinyl chloride) address resin interchange, but not plasticizer interchange. The wide range of available plasticizers requires methodology to predict plasticizer performance from a processing viewpoint. Modification of the test parameters reported in this study makes it possible to predict how plasticizer interchange affects processing under dynamic conditions.
Use of regrind in the PVC extrusion process
Authors: Rabinovitch E. B. , Booth Patrick C. 
Published: May 2005

AbstractExtrusion products that to not meet specification are generally reground for extrusion reprocessing. This paper describes the effect of heat history of regrind materials on extrusion quality, including surface appearance (melt fracture), toughness, edge tear, and heat stability. It is hoped that the information presented in this paper will help processors optimize use of regrind for best performance.
Recent developments in plasticized flame retardant polyvinyl chloride (PVC)
Authors: Green Joseph 
Published: May 2005

AbstractTriaryl and alkylaryl phosphates are plasticizers/flame retardants for polyvinyl chloride. The former are more effective flame retardants and the latter are better plasticizers. The latter also gives less smoke. A new phosphate ester blend with good plasticizer properties and low smoke is reported. A brominated triaryl phosphate ester is shown to be a highly effective flame retardant giving plasticized polyvinyl chloride compositions with oxygen index values up to 36. These compositions are suitable for high temperature wire and cable products.
Comparison of QUV accelerated weathering to outdoor exposure for PVC compounds
Authors: Rabinovitch Elvira B. , Butler Robert S. 
Published: May 2005

AbstractWeathering characteristics of the PVC compounds used for exterior applications, such as house siding, window and door frames, must be determined in order to predict their performance in actual use. In this study color weatherability of various PVC compounds, determined in the QUV accelerated weatherometer, was compared to the outdoor exposure in Arizona, Ohio, and Florida. The effect of the compound base formulation and color on correlation of the QUV to the outdoor weathering has been also analyzed.
A review of the relationship of tin content and ligand structure on stability of rigid PVC compositions
Authors: Kugele Thomas G. , Conroy Gary M. 
Published: May 2005

AbstractHistrorically, the measure of thermal performance on given PVC compositions has been approximated by the metal content of the chosen heat stabilizer. However, advances in tin and ligand chemistry necessitate the evaluation of thermal stabilizers on criteria other than metal content. Many factors including the nature of the metallic species and relative activity of the organic ligands must be considered. A discussion will be given on the facets of heat stabilizer compositions and their effects upon PVC formulations and processing. Performance criteria for organotin stabilizers. The take‐home point will be that tin content alone, in most formulations, is not the most important determinant in PVC heat stabilizer effectiveness.
Hazardous waste: The toxicity characteristic
Authors: Ledvina Joseph C. 
Published: May 2005

AbstractOn March 29, 1990, EPA promulgated the Toxicity Characteristic (TC) greatly expanding the amount of waste considered hazardous. The rule became effective six months later on September 25, 1990. Under the TC, wastes are evaluated using the Toxicity Characteristic Leaching Procedure (TCLP) to determine if the waste is hazardous. Regulatory levels were established for an additional 25 organic compounds expanding the TC constituents list to 39 substances. The regulatory level for vinyl chloride was set at 0.2 mg/1, a sufficiently high level to assure that most PVC wastes will not be hazardous because of VCM.
Effect of co‐additives on the flame/smoke suppression properties of zinc borates
Authors: Moore Fred W. , Kennelly William J. 
Published: May 2005

AbstractTwo zinc borates are useful partial replacements for the antimony oxide flame retardant normally used to flame retard flexible PVC products. The effect of using various co‐additives with zinc borates on the flame retardancy and smoke formation of a model flexible PVC cable jacket was evaluated in an attempt to further improve the properties of the formulation. The use of ammonium octamolybdate with the borates yields products with improved properties. Highly flame retarded formulations that yield low levels of smoke can be prepared by using alumina trihydrate or magnesium compounds as replacements for the usual calcium carbonate filler. Replacement of part of the phthalate ester plasticizer with brominated ester, a phosphate ester, or a brominated phosphate ester also results in formulations with oxygen values as high as 39.5 which produce lower levels of smoke.
Medical grade tubing: Criteria for catheter applications
Authors: Lambert James M. , Lee Min‐Shiu , Taller Robert A. , Solomon Donald D. 
Published: May 2005

AbstractIn 1990 there were approximately 710 million catheter units produced world‐wide from a variety of materials. This number is expected to increase 5–7% in 1991. Intravenous catheters are currently being produced from a myriad of materials including polyurethanes, polyvinylchloride, silicone rubber, and Teflon®, to name a few. Along with the ultimate end usage of a catheter, many other performance characteristics must be evaluated. Some of these characteristics are mechanical and physical properties, surface properties, hemocompatibility, biostability, and processability. The Vialon® biomaterial has a tensile strength of 520 kg/cm2 which is over 50% higher than the other materials studied. This bioengineered material, which is a member of the broad class of polyurethanes, also gave better hemocompatibility properties, as measured by in vivo platelet deposition. In addition Vialon® is engineered such that the material softens in the body's moisture and heat rendering it biocompatible. The thermoplastic nature of this polymer also allows its ease of processing by such conventional means as thermal extrusion. A comparison of the aforementioned materials against these and other performance criteria was undertaken and will be presented.
Carrier resin for a multi‐polymer solid color concentrate
Authors: Popli R. , Mauer D. H. , Witenhafer D. E. 
Published: May 2005

AbstractA multi‐polymer color concentrate has the advantage of reducing the inventory cost for the user and the manufacturer. In this paper, we present results on a carrier polymer which has been used to color a wide‐variety of non‐olefin polymers, such as PC, ABS, SAN, PMMA, PET, PS, POM, and nylons. The carrier polymer is miscible with the plastic to be colored, has excellent pigment wetting character and possesses thermal stability for processing. Data demonstrating miscibility, mechanical properties, and multi‐polymer coloring ability for many of the polymer is presented.
Polymer lifetime studies in hostile environments
Authors: Hamid S. H. , Amin M. B. , Maadhah A. G. , Al‐Jarallah A. M. 
Published: May 2005

AbstractPhoto‐oxidative degradation reactions are mainly responsible for reduced lifetime in polymers. These reactions are responsible for the decay in useful physical and chemical properties of polymers. In addition to high ultraviolet radiation doses, hostile environments have increased temperature, high humidity, and air‐borne sand. In this work white pigmented polyvinyl chloride (PVC) pipe sections were exposed to natural weather at seven different locations. Characterization studies were made on exposed samples using Fourier transform infrared (FTIR) spectroscopic, gel permeation chromatographic (GPC), and scanning electron microscopic (SEM) studies. Performance characteristics were determined by testing changes in the mechanical properties. Functional groups introduced during the processing of PVC and irregularities in the polymer chain can be held responsible for the initiation and propagation of photo‐oxidative degradation reactions catalyzed by high surface temperature and increased humidity.
Microcellular PVC
Authors: Kumar Vipin , Weller John E. , Montecillo Romano 
Published: May 2005

AbstractNovel microcellular PVC foams with a very homogenous cell distribution and cell densities ranging from 107 to 109 cells/cm3 have been created using carbon dioxide as the nucleating gas. Microcellular foams with relative densities (density of foam divided by the density of unfoamed polymer) ranging from 0.15 to 0.94 have been produced. It was found that the bubble nucleation density has and Arrhenius‐type dependence on temperature, while the average bubble diameter is relatively independent of the foaming temperature. A majority of the cell growth was found to occur in the early stages of foaming.
Selecting the proper process aid for the application
Authors: Kitai Kiyokazu , Holsopple Peggy , Okano Kenji 
Published: May 2005

AbstractWith the advent of new and demanding applications such as foam core pipe and coextruded siding and profile, coupled with the demand for more highly efficient cost/performance products in older PVC applications resulting from the desire to increase output, and with the push towards recycling, there is a strong need for efficient and effective processing aids. Process aids have been used for many years to improve the appearance and properties of PVC. In the past they were limited to low and high molecular weight products (0.3 to 0.5 reduced viscosity value), lubricating type acrylics, and some lower‐efficiency styrenics. This paper will describe a much broader range of process aids that are designed to fit the requirements of specific formulation and processing techniques. Rather than force fitting the few older processing aids into all applications, the PVC processor now has the luxury of optimizing his formulation by choosing from a wide molecular weight range of products (0.1 to 0.9 reduced viscosity value). The different structures and molecular weights of currently commercial process aids are discussed, as well as their “fit” in today's formulations.
Investigation of multiphase polymeric systems of poly(vinyl chloride)/ethylene‐propylene‐diene‐gp‐(styrene‐CO‐acrylonitrile) blends
Authors: Sudhakar K. , Singh R. P. 
Published: May 2005

AbstractThe graft copolymer, ethylene‐propylene‐diene rubber (EPDM)‐gp‐(styrene‐co‐acrylonitrile) has been synthesized by solution precipitation polymerization using benzoyl perixide as initiator. The graft copolymer has been characterized after separation through soxhlet extraction by IR, NMR, and elemental analysis techniques. The graft copolymer of EPDM is melt blended with PVC. The nature of compatibility of the graft copolymers with PVC has been studied by means of morphological analysis and by thermal analysis. The mechanical properties, Izod impact strength, tensile strength, and flexural modulus of the blends are extensively studied over the wide range of concentrations. The results of both compatibility and mechanical properties are compared with those of PVC/EPDM blends. The nature of compatibility obtained shows that PVC/EPDM blends are incompatible and the PVC/EPDM‐gp‐SAN system is semicompatible. Also, these results indicate that the PVC/EPDM‐gp‐SAN system has its highest impact strength at 14 wt% of EPDM/gp‐SAN graft copolymer. The fractured surface analysis of the impact fractured samples is also undertaken by an SEM technique. The results of the mechanical properties are discussed in view of existing theories of impact modification, along with the morphological feature of fractographs.
Processing aids for poly(vinyl chloride)
Authors: Parker Hsing‐Yeh , Dunkelberger David L. 
Published: May 2005

AbstractProcessing aids are an important class of additives for poly(vinyl chloride) (PVC). At relatively low concentration, processing aids enable the melt processing of rigid PVC and enlarge its processing windows. Discussed in this presentation are some major functions of processing aids, such as promoting PVC fusion, modifying PVC's melt rheology, and lubricating to prevent adherence of PVC melt to the processing equipment. Some examples are given to show the effects of processing aids on PVC die swell, melt fracture, melt viscosity, and PVC fusion. Commercial sources of various processing aids and typical PVC formulations for various applications are also discussed.
The coloring of PVC
Authors: Sarvis Harrey E. 
Published: May 2005

AbstractPolyvinyl chloride—PVC—has been commercial since the mid‐1930s. It is one of the most versatile of all thermoplastic resins. By the end of this year, United States consumption of PVC resin could reach 4.2 million metric tons. Some of the key markets for PVC are pipe, siding, windows, floor coverings, wire and cable insulation, and protective coatings, to name just a few. As you would expect, color plays an integral part in many of these applications. The purpose of this paper is to review the major colorant types and families that are used to color PVC, with special emphasis placed on end‐use applications. Within the context of coloring PVC, the continued use or replacement of lead and cadmium bearing colorants is discussed.
Antistatic agents
Authors: Grossman Richard F. 
Published: May 2005

AbstractThe different types of antistatic agents used in vinyl compounds are reviewed. Although each type functions generally in the same way, by formation of a two‐dimensional, hydrogen‐bonded, hygroscopic network on the surface of the finished article, there are noticeable differences in performance and suitability for various applications. Test methods are compared and working formulations for a range of applications discussed.
Improved method for detection of organotins in food simulants
Authors: Dominic Mary Rita , Koch Charles P. , Mills Jerry K. 
Published: May 2005

AbstractAn improved method for detection of organotin compounds in fatty food‐simulants has been developed. It offers improved sensitivity and specificity over complexation‐colorimetric and other methods. This method has been used to test for leaching of tin from PVC bottles stabilized with methyltin stabilizers. The results of this testing at various temperatures demonstrated safe levels for consumers.
Rigid cellular PVC—the next house siding material?
Authors: Szamborski E. C. , Buterbaugh T. E. 
Published: May 2005

AbstractThe technology for extruding rigid cellular PVC has grown substantially over the past decade. Formulation additives, tooling, and processing expertise have made possible a variety of applications—relatively complex profiles, foam‐core pipe, thermoformable foam sheet, and house siding. In the U.S. market, vinyl house siding is typically a relatively thin extrusion that is folded into a final shape that resembles wood cladding in appearance. An alternative to conventional form vinyl siding could be a foam structure that is thicker and stiffer than the solid form, and with a density similar to that of wood. This paper presents several performance advantages of rigid cellular PVC cladding in comparison to the current solid product, in addition to mentioning certain limitations that exist in the foam product that is produced with the technology available today.
Factors influencing PVC resin apparent bulk density
Authors: Kauffman Mark A. , Guise Richard S. 
Published: May 2005

AbstractBulk density is one of the easiest measured and most practical physical properties of PVC resins and compounds, especially those used in rigid applications. The paper addresses the importance of bulk density of rigid PVC resins, both regular and antistat, and their compounds. The negative influence of static electricity on bulk density measurement of PVC resins is studied and discussed. Effective static removal and accurate, consistent bulk density measurement is explored through various methods such as compacted bulk density and conditioned bulk density (either by addition of silica, methanol or carbon black, or by treatment with an ionizer).
Concentration and temperature dependence of plasticizer diffusion into plasticized PVC
Authors: Audouin L. , Andre A. , Verdu J. 
Published: May 2005

AbstractThe diffusion of a plasticizer S1 from a source made of PVC containing 25 wt% of S1 into a medium made of PVC film containing another plasticizer S2 in 15, 20, 25 and 30 wt%, was studied at temperatures ranging from 70 to 108°C. S1 was generally diphenyl‐iso‐octyl phosphate (DPIP) and S2 was dioctyl phthalate (DOP) but the reciprocal system was also studied in some cases. Starting from a reference point corresponding to a temperature of 70°C and a DOP concentration of 25 wt%, it was found experimentally that an increase Δv of the DOP volume fraction (v) or an increase ΔT of the temperature, led to the same variation of the diffusion coefficient of DPIP if ΔT/Δv ∼ 139K. A reasonably close value can be obtained from a simple free‐volume approach, using the literature data on the plasticizer action of DOP on PVC.
Mathematical modeling of rigid poly(vinyl chloride) formulations: Fusion characteristics
Authors: Bambrick C. R. , Hoegy L. R. , Ferrari L. P. 
Published: May 2005

AbstractA central composite design of experiment as used to study the effect of five additives on the fusion characteristics of a rigid PVC compound. The fusion characteristics evaluated were fusion time, fusion torque, and fusion temperature as measured by a torque rheometer. Mathematical models were constructed for the following five independent formulation variables: impact modifier, paraffin wax, calcium stearate, ester wax, and processing aid. Because of differences in the lubricating properties of these additives, mathematical modeling can help the manufacturers of rigid PVC products to understand and better formulate necessary changes to optimizes the performance requirements of their end use products. The ability to predict the fusion characteristics of a proposed formulation change will help minimize the number of required production evaluations.
A viscoelastic interpretation of miscibility for three PVC‐styrenic copolymer blends
Authors: D'Souza Nandika Anne , Letton Alan , Asay R. Elliott 
Published: May 2005

AbstractThe use of multiphase polymers is of growing importance given their inherent economical and technological benefits. Unplasticized PVC is brittle and heat sensitive. Improved impact resistance is often attained by using rubber additives. However, the rubber contributes to increasing viscosity, and, consequently, limited processability. Research efforts are concentrated on the development of a PVC matrix blend that has good heat stability and processability. While traditional PVC modification has concentrated on using plasticizers to aid processing, in this project, the use of three styrenic copolymers has been investigated. Miscibility of the systems has been established using the Rheometrics Mechanical Spectrometer by determining the number of transitions in the resultant blends. Long range time‐temperature effects have been established via generation of master curves for the two component systems. The shift factor data has been analyzed to determine the corresponding activation energies associated with different transitions. These indicate a methodology to design optimum blend systems.
Global markets for chlorine and PVC: Potential impacts of greenpeace attacks
Authors: Goodman Donald 
Published: May 2005

AbstractActivists in Europe have led the world in criticizing the potential formation of chlorinated organics, including dioxins in the manufacturing of PVC and its feedstocks. The Greenpeace publication “Dioxin Factories” claims that PVC manufacturing is the largest source of dioxins in the world and concludes that all PVC plants should be shut down. The environmentalist argument is that because some unfriendly compounds contain chlorine, all chlorine and chlorine derivative production should be banned. This review analyzes the debate, and using the Charles River Associates and CanTox Reports, comments on what is toxic and what would happen if all chlorine products were taken away.
Experience and advances in automated separation of plastics for recycling
Authors: Kenny Garry R. , Bruner Russell S. 
Published: May 2005

AbstractA new process system began operation at the Eaglebrook Plastics, Inc. facility in January 1992 that provides automated identification and separation of postconsumer plastic bottles and containers derived from baled and whole bottle sources. Since that time a number of these automated separation systems have been installed, and are in operation. This paper describes automated plastic separation systems that are currently in operation, provides operating data from the plants, and discusses advances in plastic separation methods currently under development.
Plasticizer migration from plasticized into unplasticized poly(vinyl chloride)
Authors: Papakonstantinou V. , Papaspyrides C. D. 
Published: May 2005

AbstractThere exist important industrial applications, such as hoses or plastic windows, dealing with closely combining plasticized and rigid poly(vinyl chloride). Nevertheless, migration of plasticizer causes severe variation of the mechanical performance of the end‐products. This work comprises an effort to investigate and understand these phenomena, also as an extension of previous work of ours in migration to liquid environments. The common system plasticized PVC/dioctylphthalate/unplasticized PVC was studied under two‐sided diffusion conditions, i.e., from a thin sheet of plasticized sheet. The whole assembly was placed between two glass plates and then was held in an oven at 64°C to simulate accelerated test conditions. Some pressure was also applied to ensure perfect contact between the plastic sheets. Three different levels of initial plasticizer concentration (48, 66, and 100 phr) have been considered for a period of about five months, until equilibrium was reached. During this period the migration process was monitored by weight changes. Plots of Mt/M∞ vs. t½, where M∞ the amount migrated at equilibrium and Mt the amount lost at time t, resulted in evident linear relationship. Therefore, it was proved that the Fick's law approximation for short times can be used to describe the migration kinetics for this solid/solid system. On the other hand, macroscopic observations revealed that no plasticizer was accumulated at the interface, i.e. all plasticizer leaving the plasticized sheet entered the rigid ones. Finally, it seems that the controlling stage is the diffusion inside plasticized PVC while possible annealing of the plasticized polymer structure cannot be excluded.