bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved aging and UV resistance of TPEs derived from “diimide‐hydrogenated” emulsion SBRs containing a bound antioxidant
Authors: Parker Dane K. 
Published: May 2005

AbstractIn our continuing efforts to both (1) exploit the versatility of our unique emulsion based diimide hydrogenation technology and (2) expand the performance range of hydrogenated‐SBR TPEs derived from this technology, we have investigated some of the physical and chemical effects of incorporating a polymer‐bound antioxidant into HSBR. A polymerizable amine‐type antioxidant was incorporated into the SBR structure using a conventional type “cold” emulsion polymerization recipe. For comparative purposes, unmodified and AO‐modified SBRs were then “hydrogenated” in their latex forms by the diimide technique to approximately the same extent. Samples of the extracted, isolated polymers were evaluated by DSC techniques to ascertain any effects of the bound antioxidant. Additionally, latex cast films of the HSBRs were evaluated for their initial and aged physical properties. The results of these studies indicate that while hydrogenation of SBR into the 80–90% range does dramatically improve its resistance to oxidation compared with SBR (without antioxidant), a further substantial improvement in oxidation resistance can be obtained at the same hydrogenation level by the incorporation of a bound antioxidant. Furthermore, because the bound antioxidant molecule is too large to be incorporated into the polyethylene‐like crystallites, it resides in the TPE's amorphous phase, where antioxidant protection is needed most, and does not appear to affect crystallite size, distribution, or overall initial TPE physical properties compared with the unmodified HSBRs.
Optimization of antistatic additives in polypropylene
Authors: Williams J. B. , Geick K. S. , Falter J. A. , Hall L. K. 
Published: May 2005

AbstractThe antistatic behavior of glyceryl monoesters in polypropylene (PP) is measured at concentrations down to 0.30 wt%. Water contact angles and XPS analyses are used to explore the mechanism of internal antistats. Orientation of glyceryl monostearate (GMS) at the surface of PP is determined. Several new antistat compositions for PP are introduced.
PVC corrugated drainage pipe
Authors: Pazur A. S. 
Published: May 2005

AbstractIn the continuing struggle to obtain the most economical material for a given application, it is proposed that corrugated PVC can be quite competitive with corrugated PE. An advantage for PVC stems from a flexural modulus that is almost twice that of PE. Corrugated PVC pipe at 135 grams per foot competed with corrugated PE pipe at 140–150 grams per foot. PVC requires a different corrugation design than does PE. Proper attention to balancing flexural modulus and impact strength must be paid in formulation of PVC.
More meaningful measurement of plastisol properties
Authors: Dann Bill 
Published: May 2005

AbstractThe fundamentals of plastisol rheology must be understood in order to properly select and utilize plastisol property measurements. Useful evaluation should also be made of the rheological effects of formulation ingredients and their interrelationships. Other factors such as plastisol preparation, storage conditions, process shear rates, temperatures, dwell times, and finished product specifications will influence the design of effective test procedures. Once meaningful plastisol property measurements have been developed, better quality control assurance results, and in addition quality, productivity, and profitability improvements are effected.
SQC in PVC quality control testing
Authors: Hudak Victor J. , Hoffman David E. , Smith Carol J. 
Published: May 2005

AbstractQuality control testing can be improved by applying statistical methods. For example, control testing of resins at different locations can identify idiosyncrasies in sites as well as in the testing itself. A program using standard and “control” resins in round‐robin testing between sites was designed to find the sources of variability and to develop procedures to reduce it. The test procedures were: inherent viscosity, bulk density, dry contamination, fisheyes, dry‐blend time, particle‐size distribution, and PVC resin color. Statistical quality control (SQC) charting with root‐cause analysis identified mechanical, environmental, and procedural sources of variability. Even further insight into sources comes from the reduction of variability discovered.
The biodeterioration of plasticized PVC and its prevention
Authors: Bessems Eugene 
Published: May 2005

AbstractPlasticized polyvinyl chloride will be attacked by microorganisms. The microorganisms will use the plasticizer as a carbon source, whereas favorable growth conditions, like water and oxygen, promotes their growth.A clear effect of the temperature of the water used in leaching experiments on the rate of fungal growth on the foil surface could be demonstrated. Studies also showed a difference in susceptibility of several types of plasticizers to fungal attack. The plasticizers can be divided into several classes based on their susceptibility to fungal attack.Detailed studies on the microbiological population on foil surfaces showed the predominating position of fungi. This indicated a metabiotic system between fungi and bacteria on foil surface. Addition of biocides, during manufacturing of PVC, primarily must have fungistatic properties. The fungistatic activity of 10,10′‐oxybisphenoxyarsine (OBPA) is very high, and in consequence, very low concentration must be available on foil surfaces which will prevent fungal growth. These low amounts on foil surfaces are directly correlated to the amount of OBPA insite of the foil. The transport process of the insite OBPA to the surface of the foil will principally be determined by the recepe of the foil. Therefore the application concentration recommended to ensure to achieve the minimum inhibitory concentration for fungi on the foil surface will be determined from where the application actually manifests itself.
A new family of ester lubricants for PVC
Authors: Fahey T. E. , Falter J. A. , Rosen M. 
Published: May 2005

AbstractA new class of complex esters offers the capability for tailoring lubrication characteristics to specific PVC applications. The lubricating performance of these esters can be varied from internal to external through changes in carboxylic chain length, polyol moiety, and degree of esterification. Changes in the degree of functionality of the polyol portion of the ester can be used to affect large variations in fusion time and mill stick time. Polyol functionality may also be used to control extrudate gloss without changes in other processing parameters. Dynamic stability is relatively independent of polyol type, with all of the esters providing excellent stability behavior. Carboxylic acid chain length has a pronounced effect on external lubricity, as demonstrated by large changes in mill stick time. Esters based on stearic or longer chain acids provide optimum extrusion processability and yield high gloss extrudates at low extrusion torques. Dynamic thermal stability also increases with acid chain length. The effect of degree of esterifications on lubrication is dependent upon the polyol portion of the ester. In low hydroxyl value esters, the degree of esterification can be used to vary external lubricity.
Strain‐induced crystallization kinetics of vinylidene chloride/vinyl chloride (VDC/VC) copolymers. Part III. Comparison of the effect of biaxial and uniaxial strain
Authors: Lund Monty , Steinbrunner Jim 
Published: May 2005

AbstractSpecimens of amorphous VDC/VC tube taken immediately after the water quench bath on the blown film process were stretched uniaxially and biaxially using a T. M. Long film stretcher. The stress and temperature responses were monitored. The crystalline content as a function of time was calculated based on an energy balance and the observed temperature response. It was found that SIC kinetics shows a similar dependence on extension ratio (ER) for the uniaxial and biaxial cases. The crystallization rate increases rapidly when an extension ratio of 3.5 is first reached in either the machine direction (MD) or transverse direction (TD). However, significantly greater engineering and true stress values are reached for biaxial stretching than for uniaxial stretching. This is due to the greater molecular alignment in the plane of the specimen versus the thickness direction and to the lesser specimen thickness for the biaxial case. The copolymer studied was an 88/12 wt/wt VDC/VC copolymer with a weight average molecular weight of 100,000 containing liquid additives that function as processing aids.
Poly(vinyl chloride)/plasticizer‐mixture interactions. Part I. Phthalate ester mixtures
Authors: Tomaselli F. , Gupta V. P. , Calderon H. S. , Brown G. R. 
Published: May 2005

AbstractFlory‐Huggins interaction parameters, χ, have been determined as a function of plasticizer composition for poly(vinyl chloride) in various binary mixtures of phthalate ester plasticizers using a method involving the micro‐determination of the temperature at which PVC particles in excess plasticizer appear to melt. An optimum composition at which χ goes through a minimum was found to exist for some of the systems. A good correlation between the apparent melting temperature tm and χ for the neat plasticizers with PVC was also established.
Moderating the smoke produced by flexible and semi‐rigid PVC in fire tests
Authors: Coaker A. William 
Published: May 2005

AbstractFlexible and semi‐rigid PVC formulations with high oxygen indexes and low smoke densities, as measured by the NBS Smoke Test (ASTM E662‐83) in both flaming and non‐flaming modes have been identified. The feasibility of a significant reduction of HCl emission from PVC compounds has been demonstrated in concept, and appears to be achievable when accompanied by increased oxygen index and/or significant reductions in rate of heat release and in smoke density, when measured in both the non‐flaming and flaming modes. PVC compounds, including those incorporating the kind of improvements outlined here for experimental prototypes, may be expected to compete in the future in both performance and price compared to other plastics materials.
TCLP and its impact on PVC
Authors: Grumbles Thomas G. 
Published: May 2005

AbstractToxicity Characteristic Leaching Procedure (TCLP) is the revised original EPA test method “Extraction Procedure” (EP) designed to eliminate its recognized shortcomings. TCLP, like its predecessor EP, is used to identify those wastes which pose a hazard to human health and the environment if improperly managed. The objective of both procedures is to identify wastes which pose hazards due to their potential to leach significant levels of specific toxic chemicals. The new test is designed to improve the leaching of organic constituents and expands the toxicity characteristic list to include 38 additional chemicals. The expanded criteria list of hazardous constituents includes vinyl chloride monomer. This means if a PVC sample does not pass the TCLP test it becomes a hazardous waste when discarded The regulatory burden and disposal costs then increase significantly, perhaps exponentially, Adoption of TCLP now may require PVC users to obtain Federal or State permits to install facilities to comply with regulatory standards. Indications are that EPA may promulgate the final rule in 1988, but exclude waste water.
Computerized PVC formulating for optimized cost/performance
Authors: Brofman C. M. , Caillault J. J. , Krauskopf L. G. 
Published: May 2005

AbstractThe versatility of poly(vinyl chloride) is largely a result of its capability to be modified by a wide variety of formulating additives, especially plasticizers and fillers. These additives vary widely with respect to their chemical composition, and the concentrations used in PVC, which impart significant effects on costs and performance properties. Computerized formulating programs have begun to replace laboratory testing directed at developing cost effective PVC formulations. A broad data base is required to capitalize on the many cost effective options posed to the PVC formulator. The Marketing Technical Service function of Exxon Chemical Co. utilizes COPPCO, COmputerized Profit/Performance COnsulting, to evaluate the options. The coherent data base contains 34 different plasticizers ranging from 25 to 90 phr, and can accommodate filler effects over a range of zero to 100 phr. COPPCO performs the following functions: cost and performance properties are predicted for specific formulations; lowest cost formula is defined to satisfy a specified set of performance properties; cost and performance properties are predicted for blends of plasticizers in unfilled and filled PVC compositions; performance properties are graphically presented as a function of PHR of plasticizer and plasticizer blends; graphic contours define constant property values as a function of plasticizer and of filler levels; and three dimensional response surfaces reflect the coincidental variation of both plasticizer and filler levels. COPPCO utilizes SAS (Statistical Analysis System) and Telegraph graphics, combined with sophisticated mainframe programs developed specifically to provide the desired output. Unlimited cost and performance options of the PVC formulator can be evaluated in milliseconds, vs. the traditional laboratory exercises which result in limited data after one to two weeks of sample preparation and testing.
PVC packaging recycling
Authors: Pazur A. S. 
Published: May 2005

AbstractThis study examines the recyclability of PVC bottles into other PVC products. Post consumer bottles can potentially be granulated and used, without further treatment, in the production of these products. Washing will allow the granulate to recover most of the properties of the original bottle compound, by removing paper labels and residual product contamination. Plastic contaminants, such as those from caps and other plastic bottles, show little effect on several physical properties at levels up to 3%. This granulate can thus be used as a significant portion of the raw material feed for a number of PVC products including DWV (drain/waste/vent) pipe, pipe fittings, rigid sheet, bottles, etc. Post consumer PVC bottle granulate thus constitutes a valuable resource; the recyclability of PVC packaging thus is a question of collection.
Improved CPVC compounds: Miscible alloying with styrenic copolymers
Authors: Bourland L. G. 
Published: May 2005

AbstractPrevious studies of PVC with styrene/maleic anhydride (SMAnh) copolymers showed miscibility or single phase morphology, but only at very low blended proportions of 10:1. At higher blend proportions this alloy system separated into two altered phases, neither being a pure component. Unlike PVC/SMAnh alloys, chlorinated poly(vinyl chloride) (CPVC) SMAnh systems show total miscibility for all blended proportions. The effects of alloying CPVC resins with SMAnh copolymers is the subject of this report. Using DSC and DMA miscibility of these systems are examined. Effects of SMAnh levels in these alloys on heat resistance, melt viscosity, processability, and flame retardance are assessed.
Failure analysis of rigid vinyl
Authors: Woo L. , Ling T. K. , Cheung Y. W. 
Published: May 2005

AbstractIn an attempt to better understand factors that govern the fracture resistance of rigid vinyl components, a multifaceted study was undertaken. Fracture toughness was determined by a high rate servohydraulic tester. Failure morphologies were analyzed by Scanning Electron Microscopy (SEM). In many cases, very abrupt ductile to brittle transitions were observed at moderate strain rates. In addition, since the glass transition temperature for these materials are relatively low, being of the order of 70°C to 80°C, considerable free volume relaxation or physical aging are observed at conditions near or slightly above ambient. Differential Scanning Calorimetry (DSC) was used to quantify the degree of aging. Results correlated with observed failure properties.
PVC Stabilizers of the past, present, and future
Authors: Doworkin R. D. 
Published: May 2005

AbstractWhen chemical additives were found that could minimize the loss of chemical and physical properties of a thermally‐processable but heat‐sensitive polymer called poly(vinyl chloride) (PVC), an industry was born. And with it grew the world of plastics additives. Stabilizers for PVC became and industry itself, feeding into and off of this versatile polymer industry, in an almost symbiotic relationship. There have been so many types of stabilizers in use throughout the past fifty years: inorganics, leads, organics, barium/cadmiums, calcium/zincs, organotins, and antimony. And so very many more have been conceived but not commercialized: organoleads, organoantimonys, bismuths, indiums, and a myriad of organic chemicals. What are the merits and deficiencies of these stabilizers? What of yesterday's products are still with us? What are the newer types? What might be tomorrow's products? This paper will attempt to review and discuss the past, present, and future of PVC stabilizers; the factors that are responsible for their variety, for influencing their research, development, and commercialization, and how these factors change with time.
Influence of physical aging on medical plastics properties
Authors: Woo L. , Cheung Y. W. 
Published: May 2005

AbstractProper design of medical devices requires a thorough understanding of material properties throughout the manufacturing, distribution, and end‐use conditions. Widely used amorphous polymers deserve special attention. In this article, we will focus on the physical aging phenomenon. This process affects many important properties of materials. An improved Differential Scanning Calorimetry (DSC) technique was developed to quantify the extent and the kinetics of aging. Consequences of aging were also studied with physical testing and Scanning Electron Microscopy (SEM).
A comparison of oven sag temperature and heat deflection temperature for measuring heat resistance
Authors: Balasko Michael M. , Summers James W. , Dickerson James L. , Rodriguez Ernesto L. 
Published: May 2005

AbstractThe plastics industry places great emphasis on heat deflection temperature (HDT) as a measure of heat resistance when designing a plastic product. However, many manufacturers will evaluate a material's heat resistance by exposing a finished part to meximum use temperature under gravity load rather than the high loadings associated with the heat deflection test. The oven sag test is an alternate method which looks at the sag of a molded bar under gravity load. One end of the bar is clamped while the other end is free to sag. By employing a range of temperatures, the temperature at which gross sag takes place can be found. This study investigated how well the heat deflection temperature test and the oven sag test correlate to the performance of an injection molded box subjected to high temperatures using one and two phase PVC blends. The oven sag test was found to provide a more practical and more accurate measure of a material's performance under high temperatures and no external load. It is particularly well suited for evaluating two phase polymer blends.
Molecular weight viscosity relationships for PVC
Authors: Perkins George , Haehn James 
Published: May 2005

AbstractThe inherent viscosity of PVC resin in compounds containing fillers and additives can be calculated accurately and conveniently from the weight average molecular weight or the peak molecular weight as measured by High Performance‐Size Exclusion Chromatography (HP‐SEC). Molecular weight/inherent viscosity relationships are shown for typical production PVC resins. The utility of HP‐SEC instrumentation for the determination of IV for samples of commercial interest is demonstrated. Mark‐Houwink coefficients from the literature were used to calculate a convenient conversion factor of 0.612, which can be used to convert the molecular weight measured relative to polystyrene by HP‐SEC to the actual molecular weight for PVC.
Component interactions and properties of crosslinked vinyl systems
Authors: Schreiber H. P. , Degrendele C. , Bataille Crasp P. 
Published: May 2005

AbstractCompositions based on PVC, containing DIDP or TOTM plasticizers, and in several cases also containing chlorinated polyethylene (CPE) as property modifier, have been crosslinked by irradiation, using di‐ and tri‐functional acrylic crosslinking agents. Crosslinking effectiveness has been analyzed by solvent swelling data, and the effects of irradiation up to dosages of about 10 Mrad on the mechanical properties of the systems have been recorded. The interaction potential of components used in these systems has been determined by recently‐developed methods of inverse gas chromatography (IGC). These classify PVC and CPE as electron acceptors, and the plasticizers as donors. Expectedly, increased moduli and decreased elongational properties follow exposure to gamma‐rays. The plasticizers reduce the effectiveness of crosslinking, the magnitude of the reduction being related to the degree of acid/base interaction between PVC and plasticizing fluids. When present, CPE competes with PVC for plasticizer so that for given quantities of DIDP or TOTM, the fraction available to solubilize the host polymer is reduced. In compounds with CPE, therefore, the crosslinking effectiveness of irradiation is raised, consistent with the acid/base balance of interactions, as given by the IGC results. Twin yield points have been observed in the stress‐strain curves of compounds containing CPE. It is postulated that distinct, interpenetrating crosslink networks are formed when these polymers are subjected to gamma irradiation.
Cadmium‐free stabilizer systems for flexible vinyl
Authors: Baker Paulette 
Published: May 2005

AbstractRecently, cadmium‐containing additives for plastics have been designated as undesirable environmentally. Prior to this adverse characterization of cadmium derivatives most flexible vinyl in the United States involving severe stabilizer demand during processing or service utilized metal blends based on cadmium salts. As a result many vinyl formulators have been forced to find suitable alternatives. Replacement of a stabilizer composed of specific levels of barium/cadmium salts in flexible vinyl with another containing the same levels of barium/zinc has been found to give dramatically reduced performance in heat stability tests. Results of this study has shown that satisfactory replacement of barium/cadmium/zinc or barium/cadmium systems in flexible vinyl is possible with barium/zinc stabilizers. This replacement appears to depend on higher barium‐to‐zinc ratios than those utilized in barium/cadmium analogs, use of special ligands that compensate for the smaller sized zinc cation; and prevention of their destruction by inadvertent addition of competitors.
Properties of poly(vinyl chloride) fibers crosslinked by 2‐dibutylamino‐4,6‐dimercapto‐1,3,5‐triazine
Authors: Jandó Tamás , Mori Kunio 
Published: May 2005

AbstractPVC fibers, fastened to a needle frame, were crosslinked by 2‐dibutylamino‐4, 6‐dimercapto‐1,3,5‐trizine in the presence of tetra‐n‐butylammonium bromide and alkali in water at 96°C. Solvent resistance, characterized by the gel fraction of THF, improves markedly. Mechanical properties of the fibers investigated by tensile tests at 20°C show that both the modulus and tensile strength at break increase, while elongation at break decreases over 40% gel content. Creep tests indicate that the resistance to heat deformation improves by crosslinking. The heat distortion temperature increases by 12°C at 75% gel content. Results of dynamic tests show that the Tg of PVC fibers determined by a peak in the loss modulus (E'') increases from 40% gel content. Dynamic modulus (E') increases by 74% at 23°C and the Tg by 37°C in the case of crosslinked PVC fibers having a 92% gel content. The shrinkage of PVC fibers in hot water at 94°C for 30 min decreases more than 50% over 75–80% gel content indicating the improved resistance to heat deformation.