bluuebunny/crossref_metadata_2025_split huggingface dataset:
Turning tragedy into triumph: How process accidents can benefit companies, employees, and, ultimately, customers
Authors: Lenz Douglas H. , Rovison John M. , Maser Michele A. , Hodgson Gerald M. , Pinsky Michael L. , Scott Paula , Mulholland Robert 
Published: April 2004

AbstractIn the mid‐1990s, FMC was challenged with a corporate goal of manufacturing the safest and highest quality persulfate product for our global customers. Successfully meeting this challenge required a systematic multi‐team approachutilizing both novel methods and standard tools in innovative ways to uncover the root causes of the accident. Novel and/or improved QC methods led to the creation of new product and process internal specifications, for routine QC laboratory monitoring of critical final product safety and quality specifications or parameters, and the quantification of a product parameter called “thermal stability,” an excellent indicator of product and process safety, product and process quality, and reliability. The use of this parameter as a predicator of product stability in storage, shipping, and handling was validated and benchmarked by full‐scale self‐accelerating decomposition temperature tests.The FMC persulfate process and operating conditions were subsequently modified based on lessons learned. As a result, the packaged persulfate product has not undergone a decomposition in almost eight years. Addressing productsafety automatically led to process safety improvements, and these, in turn, led to better product and process quality. Quality improvements meant better process reliability, increased capacity, reduced process downtime and operating costs, and improved customer satisfaction. Ultimately, this case study shows how safety pays!
Shortstopping runaway reactions
Authors: Balasubramanian Santhana G. , Dakshinamoorthy Duraivelan , Louvar Joseph F. 
Published: April 2004

AbstractRunaway reactions continue to be a problem in the chemical industry. A recent study showed that 26.5% of our major chemical plant accidents are due to runaways. This article reviews the (a) historical perspective of runaways, (b) state of our knowledge of how to detect potential runaways, since detection is a key element of a successful inhibition process, and (c) state of our knowledge on how to shortstop, or inhibit, reaction.The objective of the research is to improve our plants safety performance in (a) identifying methods for successfully inhibiting runaway reactions under adverse conditions, and (b) highlighting future problems and limitations, as reactions are faster and reactors more complex. Computational Fluid Dynamics (Fluent) is the tool used in this study.
Informal reasoning regarding socioscientific issues: A critical review of research
Authors: Sadler Troy D. 
Published: April 2004

AbstractSocioscientific issues encompass social dilemmas with conceptual or technological links to science. The process of resolving these issues is best characterized by informal reasoning which describes the generation and evaluation of positions in response to complex situations. This article presents a critical review of research related to informal reasoning regarding socioscientific issues. The findings reviewed address (a) socioscientific argumentation; (b) relationships between nature of science conceptualizations and socioscientific decision making; (c) the evaluation of information pertaining to socioscientific issues, including student ideas about what counts as evidence; and (d) the influence of an individual's conceptual understanding on his or her informal reasoning. This synthesis of the current state of socioscientific issue research provides a comprehensive framework from which future research can be motivated and decisions about the design and implementation of socioscientific curricula can be made. The implications for future research and classroom applications are discussed. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 513–536, 2004
Teachers' conceptions and misconceptions concerning three natural phenomena
Authors: Kikas Eve 
Published: April 2004

AbstractThis study focuses on the conceptions of trainee, primary, and subject teachers about three phenomena: the motion of objects, seasonal changes, and aggregate changes of matter. A total of 198 participants completed a questionnaire concerning two types of tasks. First, teachers evaluated the adequacy of a given explanation as compared to their knowledge of the contemporary scientific explanation. Four types of explanations were provided: a simple description, description with terms, an explanation with misconception, and a scientific explanation. Second, respondents answered multiple‐choice questions and substantiated their choices. The findings showed not only various misconceptions but also differences between the phenomena and the teacher groups. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 432–448, 2004
Using situated cognition theory in researching student experience of the workplace
Authors: Case Jennifer , Jawitz Jeff 
Published: April 2004

AbstractIt has been proposed that situated cognition theory, in which learning is conceptualized as induction into a community of practice through the activity of legitimate peripheral participation, offers an appropriate theoretical perspective for examining issues of gender in science education. This study critically engages with this proposal by means of an investigation of the vacation work experiences of a group of South African final‐year civil and chemical engineering students. Issues of race and gender appeared prominently and spontaneously in focus group and interview data. An analysis of these data using the situated cognition framework allowed for a deeper understanding of these issues and their impact on learning. It was found that access to legitimate peripheral participation was critical for good learning outcomes (associated with positive identity formation) while denial of this access (as sometimes experienced by black and female students) appeared to be related to less effective learning and poor feelings of self‐worth. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 415–431, 2004
Chemical removal of residual monomer from polyvinyl chloride latices and slurries
Authors: Marshall R. A. , Parker D. K. 
Published: April 2004

AbstractAir quality standards are becoming increasingly stringent. Stripping and gas purging of the latex are no longer adequate to reduce dryer emissions of unreacted monomer below proposed limits. New technology has been developed in which the monomer is chemically removed from the latex before the drying step to reduce monomer emissions from the dryer and to lower monomer content in the product (1). Ozonation of vinyl latex is an effective technique because of its rapid reaction with double bonds. The short half life of ozone will result in no contamination of the product by unreacted ozone. Ozonation byproducts from the reaction with vinyl chloride are nontoxic and nonpolluting. Because the ozonation reaction is specific for double bonds, the polymer structure is left intact without affecting resin physical properties.
Shear effect on the devolatilization of filled polymers
Authors: Cheng Jianya , Bigio David I. , Briber Robert M. 
Published: April 2004

AbstractThis is the second part of a systematic program to investigate the onset and mechanisms of devolatilization of filled polymeric materials. The object of this work is to study the effect of shear flow on the devolatilization of filled polymers. It is found that shear flow enables abrupt foam growth at relatively high absolute pressure in comparison to the cases without shear flow. The shear flow also reduces the threshold pressure which distinguishes two regimes of gradual and abrupt foam. In addition, an oscillatory foam growth phenomena was observed. The foam growth and devolatilization efficiency are found to depend on the imposed shear rate.
State of dispersion: Polypropylene filled with calcium carbonate
Authors: Gendron Richard , Binet Danielle 
Published: April 2004

AbstractThe influence of mixing conditions on the state of dispersion of calcium carbonate filled polypropylene composite was studied. The polymer and the filler were compounded in a twin screw extruder under various controlled processing conditions. The variables studied were the screw speed, the feed rate, the filler concentration, the barrel temperature profile and the surface treatment of the filler. The state of dispersion of calcium carbonate filled polypropylene composites was characterized using a scanning electron microscope, and was correlated to the residence time and the shearing conditions that were prevailing within the extruder. Degradation of the polymer matrix was also observed.
The role of additives in PVC market opportunities
Authors: Johnson Richard W. , Oliveri Frank J. , Szamborski Eugene C. 
Published: April 2004

AbstractAdditives can be used to provide significant performance enhancements to plastics. For PVC, particular performance benefit can be gained from additives that raise HDT, increase impact, improve color fastness, and improve processing. This paper comments on what improvements are desired in these areas, and what benefits and market opportunities would then result.
Prospects and possibilities in the realm of vinyl research
Authors: Starnes William H. 
Published: April 2004

AbstractIn most of the academic laboratories throughout the world, basic research on vinyl polymers has been of little interest for several years. To many observers, this situation has seemed illogical in view of the great commercial importance of vinyl products. Be that as it may, specific areas now exist where technological progress might well result from additional basic understanding or simply from the utilization of basic facts that already are well‐known. This paper identifies some of those areas of opportunity and suggests ways in which they might be approached. The topics considered relate to the general subjects of polymerization, stabilization, smoke suppression, and fire retardance.
A review of commercially used chemical foaming agents for thermoplastic foams
Authors: Heck Rhomie L. 
Published: April 2004

AbstractLiterally hundreds of materials have been proposed and evaluated for use as foaming agents over the past 100 years. Only a relative handful of those materials are used commercially at the present time. An extensive review of physical and chemical foaming agents was written by Henry R. Lasman for the first edition of the Encyclopedia of Polymer Science and Technology published in 1965, and is one of the best historical and technical reviews available on chemical foaming agents (1). This paper will be limited to a review of chemical foaming agents that are currently used to produce thermoplastic foams.
Injection moldable FR‐HIPS formulations based on blends of chlorinated wax and non diphenyl oxide (DPO)‐brominated flame retardant in conjunction with metal oxide/metal sulfide synergists
Authors: Siddhamalli Sridhar K. , Lee Victor W. 
Published: April 2004

AbstractA Response Surface Methodology (RSM) approach was used in performing a D‐Optimal mixture design of experiments of injection moldable fire retarded High Impact Polystyrene (FR‐HIPS) formulated with blends of Chlorez 700 SSNP (chlorinated paraffin wax) and FR‐1808 (octabromotrimethylphenyl indane, a non diphenyl oxide, brominated flame retardant that is considered more environmentally acceptable than decabromo diphenyl oxide flame retardant) in synergistic combination with antimony trioxide/zinc sulfide (white pigment) blends. An optimum processing region was identified from the viewpoint of product performance (burn time to meet UL‐94 V‐O @ 1.6 mm specification without affecting significantly other attractive physical properties) and economics that is dictated by the price of FR additives. This study has demonstrated that use of DOE offers an important benefit in formulation development and that a large number of factors can be evaluated in a relatively small number of experimental runs.
The effect of nucleating agents on glycerol monostearate antistat performance in three polypropylene resins
Authors: Dieckmann Dale 
Published: April 2004

AbstractThe effect of polypropylene nucleation on glycerol ester antistat performance is studied by measuring the electrostatic decay times of injection molded specimens. Behaviors in homopolymer, random copolymer, and block copolymer are compared. Antistat performance is related to crystallinity using DSC.
Macroscopic analysis of polyvinyl chloride (PVC) fracture modes under impact loads
Authors: Elleithy Rabeh H. 
Published: April 2004

AbstractIn this paper, the PVC impact fracture modes and processes were analyzed via the technique of successively increasing impact energies. Force‐displacement and microscopic analyses were employed at macroscopic level to study PVC fracture modes. The fracture modes were classified as: ductile, brittle, and mixed. The mixed mode was separated into: semi‐ductile and semi‐brittle. In the semi‐ductile mode, radial cracks were initiated and propagated, but were ultimatley arrested. For the semi‐brittle mode, the fracture was characterized by connected radial and circumferential cracks. It was verified that the primary elements which governed the fracture modes and impact resistance of PVC were the crack initiation and propagation processes.
Vitamin E based stabilizer components in HDPE polymer
Authors: Ho Y. C. , Young S. S. , Yam K. L. 
Published: April 2004

AbstractThe effects of individual components in a vitamin E based antioxidant formulation (CF‐120) on off‐odor release, melt flow property and yellow color property of HDPE resin pellets were investigated using a three‐phase study. The formulation consists of vitamin E, glycerol, polyethylene glycol‐400 (PEG‐400), and glyceryl monocaprylate/caprate (GMC). The resin pellets were extruded from HDPE resin powder using a laboratory scale single screw extruder. Off‐odor release from the resin pellets was evaluated using a sensory panel and GC/MS analysis. Melt flow indices and yellowness indices of the resin pellets were also measured. Screening experiment (Phase I) showed that GMC greatly contributed to off‐odor and MFI reduction; vitamin E greatly contributed to yellow color formation. Factorial experiment (Phase II) confirmed that GMC was the major off‐odor contributor. Response surface experiment (Phase III) showed that yellowness index and odor score reasonably correlated to vitamin E and GMC concentrations; MFI and nonanal concentration did not correlate well with vitamin E and GMC concentrations. The identification of octanoic acid by GC/MS from HDPE resin pellets suggested that possible thermal/mechanical degradation of GMC might occur in extrusion. The results are useful for designing a better vitamin E formulation for reducing the off‐odor, without significantly enhancing yellow color formation.
Approximate model for analyzing frozen‐in strains and shrinkage of extruded PVC lineal profiles
Authors: Ray Harrell E. 
Published: April 2004

AbstractA mathematical model, based upon utilization of an “approximate” time‐temperature superposition for estimating stress‐strain properties of PVC, was derived for analyzing shrinkage of extruded PVC profiles. The model is composed of a single deformation, followed by a strain recovery (shrinkage) at the same or a different temperature. Profile shrinkage at any given time and temperature can be reduced by decreasing the magnitude of the imposed frozen‐in strain, increasing the temperature at which the strain is imposed, and/or increasing the time that is required to impose the strain. The model provides good estimates of the shrinkage of extruded profiles.
Effects of morphology on the fracture toughness of PVC‐U pipe
Authors: Kuriyama Takashi , Narisawa Ikuo , Shina Richi , Kotaki Masaya 
Published: April 2004

AbstractThe effects of processing conditions on the deformation and fracture behavior of PVC‐U pipe have been studied in terms of fracture toughness, following the BS 3505 standard. The processing conditions did not strongly affect the yield strength or elastic modulus, whereas FT (fracture toughness) values linearly increased with an increase of gelation levels. Microscopic observations of the damage zone ahead of the notch in C‐ring specimens, when loading was interrupted at half of creep life, showed that many voids and delaminations initiated from primary PVC particles in the higher gelated pipes, whereas multiple cracks between sub‐grains occurred in the lower gelated pipes.
Processing window in impact‐modified rigid PVC
Authors: Berard Mark T. , Ventresca Don A. 
Published: April 2004

AbstractA method is described for quickly evaluating the processing window of impact‐modified rigid PVC formulations. This involves mixing the compound in a bowl mixer at various temperatures and to various levels of total work input. The impact properties are measured and plotted as a contour map versus melt temperature and work input. The melt temperature is the dominant factor in controlling the impact processing window. The total work input is a secondary effect, which mainly influences the system through shear heating effects on the melt temperature. This method was used to evaluate formulations with different impact modifiers and lubricant and filler levels. Impact modifier type, polyethylene wax, and filler concentrations are the dominant factors. The mechanisms involved are discussed.
The structure of lead stabilizers. 3: Reaction products with HCl
Authors: Grossman Richard F. 
Published: April 2004

AbstractThe reaction of HCl with stabilizers such as dibasic lead phthalate, tribasic lead sulfate, and dibasic lead phosphite leads to a series of previously uncharacterized chlorinated derivatives. These compounds exhibit an interesting and hitherto unknown chemistry. Some are heat stabilizers in their own regard.
Ultraviolet light resistance of vinyl miniblinds. Part 2: Reaction products formed by lead in air
Authors: Grossman Richard F. 
Published: April 2004

AbstractAccelerated ultraviolet light aging was carried out using lead stabilized commercial vinyl miniblinds as well as a vinyl composition designed for outdoor use. The levels of surface lead found after such exposure were compared to results obtained in the field by the North Carolina Department of Environment, Health, and Natural Resources (DEHNR).
The influence of rotational molding cycle on the morphology and physical properties of FR‐LLDPE
Authors: Siddhamalli Sridhar K. , Lee Victor W. 
Published: April 2004

AbstractThe major objective of the study was to develop formulations having maximum impact strength while maintaining a UL‐94 V‐0 flammability rating. Excellent impact strength and flammability performance were achieved in the modified FR‐LLDPE system at 20% impact modifier (ethylene copolymer), 22% flame retardant, 5.5% antimony trioxide, 0.25% PTFE, and 0.5% functionalized silicone additive. This paper further explores the performance of the aforesaid optimized FR‐LLDPE composition when rotomolded at various cycle times. Attempts were made to probe the influence of morphological characteristics on the physical properties of the rotomolded parts.
New soluble teflon for coating onto plastics
Authors: Stewart Charles W. , Wheland Robert C. , Anolick Colin , Tattersall Thomas L. 
Published: April 2004

AbstractTeflon PTFE, FEP, and low melting HFP/TFE copolymers can be made to have excellent adhesion to substrates if residual stresses from large changes in temperature can be eliminated. PTFE and FEP can be adhered using a high boiling saturated perfluorinated oligomer to plasticize the fluoropolymer at the interface. Low melting HFP/TFE copolymers can be deposited as very thin films from solution in common perfluorinated solvents. Highly durable coatings can be prepared owing to the intimate degree of contact obtained between the substrate and the fluoropolymer chains. The use of low boiling solvents allow coatings on temperature sensitive substrates, such as plastics, rubber, and paper. Possible commercial applications range from mold release coatings, clear protective coatings on photographs, paintings, and documents and optical coatings on plastic and glass.
Stain resistance in resilient sheet flooring applications: The role of the plasticizer
Authors: Colletti T. A. , Renshaw J. T. , Schaefer R. E. 
Published: April 2004

AbstractStain resistance, or more properly, appearance retention, is a complex phenomenon in resilient sheet flooring applications. The process can be complex, involving the plasticizer, the overall toughness (or abrasion resistance) of the wear layer, and the thermoplastic nature of plasticized PVC. This paper explores the plasticizer related portions of the stain resistance phenomenon. Data are presented to illustrate relationships between stain resistance and plasticizer structure, concentration, extraction resistance, volatility, and solubility parameter.
New silicate‐based powders for fire protection of thermoplastics
Authors: Liu T. M. , Baker W. E. , Langille K. B. , Nguyen D. T. , Bernt J. O. 
Published: April 2004

AbstractA new, intumescent powdered silicate additive for plastics (polyethylene and polyvinyl chloride) has been investigated that gives improved flame retardancy. Cone calorimeter evaluations of the compounds of polymer/powder show reduction in peak rate of heat release, total heat release, and rate of mass loss. The effects of various polymer/powder ratios and powder particle sizes on the fire protection performance are shown. The morphology of this powder and the polymer/powder compounds before and after combustion is observed. A fire‐protection mechanism is discussed that suggests the importance of an interpenetrating char structure.
Emerging technical and society trends—opportunities for vinyl: A look at the future and how the vinyl industry can respond for growth and profit
Authors: Summers James , Parsons Mark , Hawrylko Roman , Shakir Saleem , Jarus David , Kaminski Ronald , Bowler Peter , Rodriguez Ernesto 
Published: April 2004

AbstractThe vinyl industry has a rich history of providing solutions to society's needs. These include flame‐resistant wire insulation, piping systems for safe drinking water, and weatherable, flame‐resistant systems for siding, windows, auto interiors, floors, and pool liners. Also included are shatter‐resistant clear containers with handles, safe blood supplies and intravenous solutions, and flame‐resistant computer housings and electrical boxes. These are but a few of the things of which the vinyl industry can be proud.The vinyl industry is mature, and as in many other mature industries, much of the technical and business effort goes into running the day‐to‐day businesses, putting out fires, reducing costs, and driving efficiencies. If poorly managed, this will be an all‐consuming effort, leaving no thought and no effort at all on longer‐term business opportunities. The future will look much different than today. Identifying future trends will allow well‐managed companies, looking for these future business opportunities, to seek out and set aside some efforts for developing future technologies and businesses. In this paper we discuss some future trends and needs, such as inexpensive and safe drinking water, personalized public transportation, prevention of resource depletion, high‐powered energy packages, nonpolluting energy sources, human genetic engineering, e‐bombs, and computers. The opportunities for the vinyl industry to participate in these changes also are discussed.