bluuebunny/crossref_metadata_2025_split huggingface dataset:
Refractive index—A key to understanding color differences
Authors: Donald B. , Mathew R. 
Published: May 2005

AbstractA problem encountered in the instrumental evaluation of color is the use of integrating sphere spectrophotometers to compare materials where the standard color plaque is not constructed from the same material as the sample. This problem is encountered in the automobile industry, where polypropylene master plaques are commonly used as the standards constructed from different materials than the sample being evaluated. The paper demonstrates how these problems result from the impact of a polymer's refractive index on the reflectivity of light from its surface, and the effect of this light on the instrumental evaluations of color. The paper also discusses how the Fresnel equation can be utilized to calculate the amount of light reflected from a polymer's surface and describes a mathematical procedure that can help compensate for these differences when matching and approving colors.
Flexible PVC challenges for the formulator
Authors: Wickson E. J. , Brookman R. S. 
Published: May 2005

AbstractThe ability of PVC to tolerate large amounts of plasticizers, fillers, and other additives is unique among thermoplastics and has made it possible to develop a wide range of properties in flexible PVC. This versatility, coupled with attractive economics, has been responsible for the growth of flexible PVC over the years. Unfortunately, growth has been slow for many years and flexible PVC markets have been encroached on by competitive materials with higher performance and/or styling advantages. Reasons for the vulnerability of flexible PVC are discussed. In some cases, only minor changes are needed to improve performance while in other cases new developments are needed, many of which are available but not exploited.
Ultra‐high molecular weight PVC resins
Authors: Attwood P. C. , Brookman R. S. 
Published: May 2005

AbstractUltra‐high molecular weight PVC resins have properties similar to conventional homopolymer resins, except for a few significant differences. Compounds utilizing these polymers display improved toughness qualities and utility in a wider temperature range. These upgraded properties, combined with the usual advantages of PVC such as colorability, processability, and chemical resistance, should permit these PVC compounds to enter markets previously excluded. New potential markets suggested are footwear utilizing the lighter weight advantage of these tougher compounds, automotive under‐the‐hood applications that employ the broader temperature properties, and replacements for elastomers in gasket and compounds used in automotive and appliance applications.
Update on smoke toxicity of vinyl compounds
Authors: Hinderer R. K. , Hirschler M. M. 
Published: May 2005

AbstractAll organic materials burn and give off toxic products. These always include water, carbon dioxide, and the single gas causing the greatest hazard in fires—carbon monoxide (CO). The intrinsic toxicity of the smoke of all combustible materials, including PVC, is very similar in terms of lethality, with very few exceptions. Toxicity of vinyl compounds is due to two major gases: CO and hydrogen chloride (HCI). Since natural combustible materials are not chlorinated, speculation has arisen about the toxicity of HCl and of PVC smoke. Recent studies have shown that it takes similar doses of HCl and CO to kill rats. Furthermore, rats and baboons will tolerate the same levels of HCl. However, mice are much more sensitive than either rats or baboons towards HCl. Baboons are a very good model for humans; therefore, mice will be killed by exposure to much lower HCl levels than those required to kill humans. HCl concentrations in real fires are quite low: HCl decays rapidly by reacting with wall materials such as gypsum, cement, or ceiling tile. It does not, however, react rapidly with plastic or glass walls, which is where toxicity tests are carried out. Therefore PVC smoke is less hazardous in reality than it appears to be from toxicity test results. Since most products have similar intrinsic toxicities, as regards lethality, the real toxicity in a fire is a consequence of the rate of generation of gases. PVC is a difficult polymer to ignite and burns very slowly, so that it will give off less toxic products per unit time than many other common materials and cause lower fire hazard.
Corrosivity of smoke towards metals
Authors: Hirschler M. M. , Smith G. F. 
Published: May 2005

AbstractMany people believe that smoke is corrosive only if it contains acid gases. This leads to associating corrosive potential of smoke from materials directly with the amount of acid gases emitted from them during combustion. In extreme cases, chemical composition (i.e. halogen content) is used as a substitute measure of corrosiveness and, therefore, of material suitability for certain applications. The reality is, however, that everything is usually heavily corroded in a fire, whatever the combustible materials involved. In the present project sets of 5 flat carbon steel coupons and 2 copper mirrors were exposed to smoke from several materials for 1 h, in a chamber at room temperature and at 100°C, and kept for 28 days at 75% relative humidity. Various surface treatments were also studied.The combustibles tested were: a PVC wire compound (PVC WR), a low acid PVC wire compound (PVC LH), a halogen free polyethylene wire compound (PE), wool, wood (Douglas fir, DFIR), polystyrene (PS), neoprene (NPR), nylon (NYL), and a blank (no sample). In order to determine corrosivity the resistance of the copper mirrors and the loss of metal from them was measured. All copper mirrors lost their electrical properties: an almost infinite resistance was measured post‐exposure. The amount of copper lost was very similar for all smokes, but, in the 100°C experiments, the smoke corrosivity ranking was:

All steel coupons were corroded too, at least to some extent. The amount of iron lost depended on treatment as well as on the smoke used. In particular, the highest degree of corrosion was found with coupons exposed at very high temperature, where, again, the most corrosive smoke came from nylon. Common wisdom suggests that acid gases result in corrosion of metal. The present work substantiates this fact. However, the acid gas concentration in the atmosphere does not normally correlate with the level of metal corrosion. The results of this work indicate that metal corrosion depends on factors in addition to acid gases: type of metal, temperature, humidity, length of exposure, surface treatment, and geometry. Furthermore all smokes tested are corrosive.
Vinyl in medicine—a special case
Authors: Blais P. 
Published: May 2005

AbstractPolyvinyl chloride (PVC) has been used in health care products for more than forty years. Presented originally on the basis of convenience for field and trauma medicine in the military context, the new plastic slowly displaced rubber and glass in intravenous fluid administration systems and later enabled low‐cost production of many new medical products. It was a strong factor in the evolution of hospital disposables. Such substances, long accepted as “low toxicity PVC generiecs” or “medical PVCs” are now being challenged by new classes of materials specifically designed for clinical use. The narrow range of properties offered by traditional PVC technology can no longer fulfill all needs. The choice of new plastics is rationalized on the basis of specific physico‐chemical, mechanical, toxicological, aesthetic, or economic consideration. This presentation addresses the limitations of a plastics technology based on empirical multicomponent formulations as opposed to one based on polymer engineering for critical bilogical, laboratory, and medical applications. Material stability in biological environments, the role of additives, the toxicology of leachables, the biocompatibility of generic medical PVCs, as well as the reasons for its success in health care are discussed. Criteria of suitability for plastics in medicine, the commercial prospects for new PVC blends and copolymers for health care, and the role of national regulatory agencies in decisions that affect the choice of materials for health care, food, and beverages are also discussed.
Effect of injection molding conditions on creep rupture and flex fatigue of rigid PVC
Authors: Forsyth T. H. , Butler R. S. , Summers J. W. 
Published: May 2005

AbstractRigid PVC is used in applications requiring long term performance and is sometimes produced under non‐optimal conditions, so that an understanding of the processing variables that affect long‐term performance needs to be obtained. In this study, injection molding parameters were varied according to a statistically designed plan to permit construction of predictive equations for creep rupture, flexural fatigue, and environmental stress cracking. The results show that these properties are strong functions of melt temperature, PVC compound formulation, and of the polymer structure formed during molding.
Evaluation of PVC formulations meeting the various cell classifications in ASTM D‐3034
Authors: Kupfer A. D. 
Published: May 2005

AbstractMost PVC gravity sewer pipe is manufactured according to the specifications in ASTM Standard D‐3034. This pipe must be extruded from a dryblend which meets one of the three cell classifications listed in the standard. Several PVC formulations which meet these cell classifications are evaluated in this paper. Physical properties such as tensile strength, stiffness, and izod and drop dart impact are measured using both laboratory prepared as well as production run samples. Dryblend flowability is studied using the Jenike and Johnson Flow‐Factor‐Tester. The results show dryblend flow properties will significantly vary as the calcium carbonate filler level in each formulation increases. The use of a coated vs. uncoated filler will improve flow properties especially at higher filler loadings. An analysis of dryblend cost vs. resin price shows resin prices will affect what cell classification is the optimum one to use. Also, maximum filler usage may not result in an optimum cost savings if additional additives such as processing aids or impact modifiers are needed.
Coated metals compatible with PVC jackets for bonded sheath cable applications
Authors: Bow K. E. , Pikula D. G. , Grosser B. K. , Leng P. B. 
Published: May 2005

AbstractMechanical strength in the cable sheath is particularly valuable for both fiber optical and copper pair cable. By bonding a PVC jacket to a coated metal tape, a mechanically strong sheath construction is obtained. Changes in PVC jacket technologies have created the need for PVC compatible coated metals with greater tolerance for variations in PVC jacketing materials. This need has been met by the development of a variety of coated metals having thermoplastic coatings which adhere to PVC. As a consequence of this development, new cable sheath designs for use in a variety of applications, such as riser cable and direct buried cable destined for local area networks, are possible. These cables may utilize both copper conductors and/or optical fibers for signal transmission. Data will be provided in the paper to show the effects of extrusion process conditions on adhesion for a variety of PVC resins. The properties of a variety of coated metals—aluminum, copper, and steel—will be discussed. Data on environmental tests of adhesion will be presented. Relationships between adhesion, metal characteristics, jacket properties, and mechanical performance of the sheath will be discussed. Cable applications for the PVC compatible metals will be discussed. Data on the performance of the bonded sheath in riser cable and buried local area network cable will be presented. New cable applications where coated metals in the sheath can provide lightweight armoring will also be discussed.
Sintering of PVC
Authors: Crolla G. , Menges G. 
Published: May 2005

AbstractAlthough PVC is counted as one of the amorphous plastics it possesses a distinct powder grain structure. This structure is responsible for various effects; for example it is impossible to sinter thick pieces of rigid PVC dryblend possessing satisfactory mechanical properties. For this application, it is necessary to break down this powder structure into smaller parts, called primary particles, by mechanical shearing and covering these particles with processing auxiliaries enabling it to be sintered. PVC can then be melted by the influence of temperature and pressure in the same way as other thermoplastic materials. For this reason, tests were carried out to determine the best material configuration and the necessary data for the compounding and shearing process, and the sinter conditions. A continuously working roll mill was used to break down the structure. The rolls of this equipment are provided with grooves inclined at a certain angle. With this construction it is possible to achieve a high shearing rate at a low mass‐temperature. Furthermore, all additives can be added during the rolling process, so that no additional mixing process is necessary. These gelable pellets, made by the roll mill, can thus be formed in a die into plates of different thicknesses. Samples were pressed by varying compounding and sintering conditions and these were tested for mechanical properties.
Scanning electron micrograph study of the impact‐improved MBS/PVC blends
Authors: Fann D.‐M. , Shih H.‐Y. , Hsiao C.‐M. , Huang S. K. 
Published: May 2005

AbstractThe improvement of the impact strength of the telecommunication equipment using injection moldable PVC/MBS and other modifiers were studied. The addition of MBS to the PVC was found with rapid increases in the impact stregths in Kg‐cm/cm: 5.5 of pure PVC; 80 of 12 phr and the maximum of 131 of 20 phr of MBS. This increasing impact strength phenomena were subjected to close examinations of SEM, DMTA, and strain‐stress diagrams. The DMTA analysis of the retaining of the individual Tg's of MBS and PVC in the MBS/PVC blends, indicates that no miscibility of MBS and PVC has occurred. The DMTA diagrams of 5, 12, 20, and 30 phrs of MBS in PVC were analyzed and the same samples were also subjected to the impact strength measurements and the SEM examinations. SEM photos showed a gradual transition of the linear to the three‐dimensional arrangements had occurred in the PVC/MBS blends. The formation of three‐dimensional arrangement occurred between 10–20 phr of added MBS. The spacial change from linear to the three‐dimensional arrangements observed in SEM photos correlates the rapid increases of the impact strengths of the specimens tested. Injection specimens of the telephone sets made of PVC/MBS blends with 20 phr of MBS in PVC indicate that the impact strength is averaged at 115 Kg‐cm/cm with tensile strength of 330 Kg/sq cm and elongation of 150%. The similar change of the spacial arrangement is also observed in their SEM photos.
Contribution to the development of thermal stabilization system for vinylidene chloride co‐polymers
Authors: Bednarik Ladislav 
Published: May 2005

AbstractSelected compounds of phosphorus and tin improve the thermal stability of vinylidene chloride co‐polymers. Although offering superior intermediate color stability, incorporation of polyols will result in erratic processing of the PVdC. Combinations rather than individual compounds appear to stabilize PVdC more effectively and an explanation of the stabilization mechanism is attempted for some compounds.
Use of DSC as a quality control tool
Authors: Williams J. B. 
Published: May 2005

AbstractA differential scanning calorimeter (DSC) has been found to be a very useful quality control tool for a manufacturer of rigid PVC products. It is particularly good at measuring the consistency of lubricants such as paraffin waxes, and ethylene bis‐stearamide. Test results are presented which clearly show the difference between two paraffin waxes, both of which were considered identical from normal wax specifications, but which performed differently in production equipment. Also presented are the statistics used to draft raw material specifications which include DSC measurements.
Studies on the preparation and properties of particle boards made from bagasse and PVC. I: Effects of operating conditions
Authors: Maldas D. , Kokta B. V. 
Published: May 2005

AbstractUnder study were the mechanical properties of particle boards comprised of ground sugarcane bagasse, PVC, and poly{methylene (polyphenyl isocyanate)} [PMPPIC]. The effects of different parameters, e.g. mixing temperature, molding conditions ‐ platen temperature, time and pressure, particle size of bagasse, concentration of PVC and PMPPIC, as well as dilution of PMPPIC, on the mechanical properties of the resulting particle boards were also investigated. In general, the properties of particle boards change with the variation of mixing and molding conditions. A mixing temperature of 175°C and molding conditions [platen temperature, 190°C; time, 10 min; and pressure, 3.8 MPa] were believed to be optimal conditions of compounding particle boards. Both the mechanical properties and the density of particle boards of bagasse with a mesh size of 60, improved up to 20 weight % of PVC and 10 weight % of PMPPIC.
Mixed metal vinyl stabilizer synergism—reactions with model compounds
Authors: Grossman Richard F. 
Published: May 2005

AbstractAn allylic model compound for degrading PVC, cinnamyl chloride, was found to react with metal carboxylates in n‐butyl acetate at 50°C with rates first order in each component. The corresponding metal chlorides and a mixture of rearranged and unrearranged allyl esters were isolated. With cadmium carboxylates, the rate constant is of the order of 300 × 10−5 sec−1; with barium carboxylates, two orders of magnitude slower. In the presence of excess barium carboxylate, the rate of reaction is first order in cadmium and independent of barium concentration; the product is, however, barium chloride. Under such conditions, only unrearranged allyl ester is recovered. These observations are interpreted in terms of a rapid step leading to formation of a carboxylate‐bridged barium/cadmium intermediate. It is proposed that such intermediates displace chloride from allylic carbon by a concerted mechanism, generating chloride‐bridged reaction products that collapse exclusively to barium chloride.
Vinyl—a new blow molding polymer
Authors: Kochanski James W. 
Published: May 2005

AbstractVinyl is used in a wide range of applications, not only in packaging but also in construction, automotive, and other areas. Vinyl (polyvinyl chloride, or PVC) has maintained a significant presence in some markets for more than 30 years. Yet vinyl is not necessarily on the downward leg of its product life cycle. New, more effective PVC blow molding compounds are being developed and introduced. These versatile new polymers are extending the life cycle of vinyl packaging into the 21st century. The long‐standing success of vinyl in bottle applications is due to a number of key properties, including its chemical resistance, UV stability, low mold costs, design flexibility, low permeability, and aesthetics. In recent years, improved PVC compounds have created new growth markets for vinyl. Three important ones are hot‐fill applications, personal care products, and bottled water. The potential of vinyl bottles to become a major factor in the fast‐growing bottled water market is a particularly good example of the adaptability and versatility that make vinyl one of the most exciting “new” blow molding polymers.
Plasticizers: A consideration of their impact on health and the environment
Authors: Cadogan D. F. 
Published: May 2005

AbstractPlasticizers have been used for centuries to improve the processability and flexibility of a variety of materials. At the dawn of civilization water was used to plasticize clay for the production of pottery and clay tablets and the Ark was reputedly waterproofed with pitch plasticized with oil. Today the most common plasticizers are phthalates, adipates, and similar esters the majority of which are used to produce flexible PVC products. The widespread use of plasticizers in these applications over the last forty years has resulted in their toxicology being extensively researched and understood. As a consequence of these investigations many official bodies and legislative authorities have concluded that plasticizers pose no significant hazard to man or the environment. Plasticizers will, therefore, continue to be used to enhance all our lives through the production of a wide variety of PVC items ranging from medical components to waterproof clothing and floor coverings.
Evaluation of secondary lubricants for rigid PVC extrusion
Authors: Hughes Paul C. , Mieure K. G. 
Published: May 2005

AbstractA common system of primary lubricants in rigid PVC extrusion compounds is calcium stearate plus paraffin wax. Secondary lubricants are frequently added to this system at low concentrations with the intention of improving such properties as metal release, thermal stability, plateout, extrudate surface appearance, etc. This paper discusses the results of laboratory studies designed to evaluate the contribution to these properties of two commonly used secondary lubricants: AC629A, an oxidized low molecular weight polyethylene, and K175, an acrylic “lubricating processing aid.” Surprisingly, the testing showed little improvement in performance when these auxiliary lubricants were added.
Testing variability in viscosity measurements of PVC plastisols
Authors: Breslin Bridget K. , Moran Michael T. 
Published: May 2005

AbstractAn experiment was conducted to compare the variability of the Brookfield Viscometer, the Severs Extrusion Rheometer, and the Haake Rotational Viscometer in measuring flow characteristics of PVC plastisol. The author discusses variability of the different test methods involved with the Severs and the Haake viscometers. Also discussed are operator, environmental, and day‐to‐day variation.
The use of statistical process control in batch processed PVC compounding
Authors: Brown David J. 
Published: May 2005

AbstractThis paper describes the main Statistical Process Control (SPC) method that is being used by Canada Wire and Cable in the manufacture of their flexible PVC compounds. It outlines the benefits that are being realized by following a systematic approach towards using control charts. By employing SPC as a quality improvement tool, the operation has reduced its costs by an estimated $180,000 per year.
Processing morphology of PVC/MBS blend
Authors: Kadokura M. , Momii T. , Hirata H. , Okuda Y. , Kobayashi H. 
Published: May 2005

AbstractMBS resin, an impact modifier for PVC, plays an important role in PVC processing, the details of which, however, are not well understood. The use of a temperature programmable Brabender Plasticorder and new microscopic techniques have revealed that MBS inhibits the comminution of PVC grain in the initial stage of processing, and PVC breakdown occurs after the MBS melts. Dynamic melting of MBS is observed as a Brabender torque peak. These characteristics of PVC/MBS blends are quite different from those of PVC/processing aid blends. Processing features of PVC/MBS blends are reported and compared with those of PVC/processing aid blends.
UV protecting layers on PVC made by plasma polymerization
Authors: Leiber J. , Michaeli W. , Telgenbüscher K. , Stollenwerk M. 
Published: May 2005

AbstractUV protection is necessary for many plastics if they are to be used for outdoor applications. Plasma polymerization, a new surface coating technology, permits the depositing of thin polymer layers on plastics as UV and weather protection. With these layers, even the UV resistance of polyvinylchloride (PVC) containing a conventional UV stabilizer can be improved; After a QUV panel test of 5000 h the plasma polymerized films show a decrease in the degree of yellowing by a factor of 3 compared to the uncoated samples. Different types of monomers and other process parameters of the plasma polymerization apparatus show a significant influence on deposition rates, surface chemistry, and UV protecting properties.