SPE Library

The SPE Library contains thousands of papers, presentations, journal briefs and recorded webinars from the best minds in the Plastics Industry. Spanning almost two decades, this collection of published research and development work in polymer science and plastics technology is a wealth of knowledge and information for anyone involved in plastics.

The SPE Library is just one of the great benefits of being an SPE member! Are you taking advantage of all of your SPE Benefits?

Not an SPE member? Join today!

Use % to separate multiple keywords. 

Search SPE Library

Sort By:  Date Added   Publication Date   Title   Author

Conference Proceedings

Three-Dimensional Simulations of the Inkjet Printing Process for PLED Display
Kun-Lin Hsu, Shiu-Wu Chau, Shia-Chung Chen, Tong-Miin Liou, Kuan-Chen Shih, May 2004

Because the inkjet deposition process reduces manufacturing costs and process steps when compared with the traditional etching and/or lithography, it seems to be an attractive alternative in the PLED display manufacturing processes. However, some microflow issues in the deposition process should be carefully treated to ensure the manufacturing quality of the PLED display. The droplets dispensing from the inkjet head, which generally contains an array of nozzles, have a volume in several picoliters, while each nozzle responds very quickly and jets the droplets into cavities on substrates with micrometer size. The nature of droplet impingement depends on the material properties, the initial state of droplet, the impact parameters and the surface characteristics. The commonly chosen non-dimensional numbers to describe this process are the Weber number, the Reynolds number, the Ohnesorge number, and the Bond number. This paper discusses the influence of droplet initial velocity on microflow characteristics in the deposition process via a numerical approach. The numerical investigations show that for the studied droplet and cavity size, an acceptable velocity range has been found to ensure the deposition quality, while this result agrees well with existing industrial experiences. The numerical simulation seems to be an efficient and reliable way to evaluate the inkjet deposition process.

The Effect of ? -Rays on PES/PA6 Blends
C. Albano, R. Perera, P. Silva, Y. Sánchez, C. Rosales, M. Becerra, May 2004

In this work, the effect of ? -rays irradiation and post-irradiation storage time onto different PEs, PA6 and their blends was studied by means of ESR spectroscopy, FTIR and DSC. These techniques can provide relevant information concerning the reaction mechanism of the polymers structural modifications that take place during their irradiation. The experimental results suggest that allyl, alkyl and polyenyl radicals are generated in the materials after the irradiation process. The dynamics dominating the process kinetics are crosslinking, chain scission and a coexistence of both, depending on the sample composition. The storage time produces a change in the kinetics dynamic.

Determination of the Pressure Coefficient of Polymer Melts from Shear Flow
Tomas Sedlacek, Martin Zatloukal, Anezka Lengalova, Petr Filip, Petr Saha, May 2004

A modified capillary rheometer was used to measure strain rate-temperature-pressure dependencies of shear viscosity for injection molding grades of polymers. The modification consisted in the addition of a second chamber and a restricting needle valve below the main die, and its purpose was to determine the effect of pressure on the shear viscosity of different polymer melts. The modified White-Metzner model was employed to simultaneously fit the measured viscosity data and determine the pressure and temperature coefficients, ? and ?. It has been found that not only the temperature but also the pressure factor significantly influences viscosity, and both of them are useful for the description of a polymer behaviour.

Testing the Effects of Hold Pressure on Hold Time in Various Materials and through Various Gates
J.J. Gropp, May 2004

The holding phase of the injection molding process can be critical to producing quality parts. This paper studies the relationship between hold pressure and hold time with a variety of gate types and materials. The materials will be broken into groups such as semicrystalline, amorphous, and filled materials. In addition, parts will be created with a variety of different sized and shaped gates. From this, it is believed that a pattern will be recognized with regards to the setting of hold pressure on the necessary hold time. This pattern is intended to give processors a theory with which to base their thought process when optimizing injection molding machines.

The Affects of Shear Induced Imbalance on the Concentricity of Injection Molded Gears
Brock Allen, Thomas Lacey, May 2004

A number of studies in recent years have shown that shear induced melt variations developed in the runner result in cavity to cavity filling imbalances in molds with eight or more cavities. This study looks at the affects of the shear induced melt variation when molding high precision parts in molds with as few as two cavities. In particular is the case of gears which require high concentricity. The shear induced melt variations developed in the runner continue into the cavity creating irregular filling and non-concentric part shapes.This study evaluates a two cavity, three plate, cold runner, center gated gear mold. Gears are molded from a variety of different engineering resins, and the effects of the shear induced melt variation are evaluated.

Electrospinning: Preparation of Continuous Nanofibers
Sian F. Fennessey, Richard J. Farris, May 2004

Electrospinning is an approach to fiber production, which relies on electrostatic forces to produce fibers with diameters in the range of 10nm to a few microns. Nonwoven nanofiber webs of Polyacrylonitrile (PAN) were prepared from solution with Dimethylformamide, with the purpose of preparing carbon nanofibers for the reinforcement of composites. Reproducible fibers with diameters between 0.38-1.5?m (FESEM) were prepared from 10-15wt% solutions electrospun between 8-16kV. The velocity of a 10wt% solution electrospun at 16kV was determined to be between 140-160m/s, from the collected mass. Partially aligned and oriented PAN nanofibers have been prepared using a high speed, rotating take-up wheel.

Modified Three Stage Injection Molding Study
Michael E. Hucko, Mark Cortese, Jeffrey Reed, May 2004

The primary use of a three-stage injection molding process is to produce a process that is more stable. However, a disadvantage can be encountered when the gate end of the part is packed out more than the last portions of the part to fill. A comparison will be made between a three stage and a two-stage cycle that is to be set up on a single cavity mold. Here, an attempt to modify the three-stage process to look like a two-stage process will be made. The injection pressure profile will be changed by adjusting the pack velocity, so that there will be no pressure spike and a constant slope during packing. Once this is completed, disks will be compared and rules to accomplish this will be created.

Reactive Compatibilization as a Route to High Performance Engineering Plastics
Donald R. Paul, May 2004

Engineering thermoplastics provide a platform for generating light-weight structural materials with customized performance. Such formulations often involve blending with other polymers to gain additional toughness, stiffness or resistance to heat, chemicals, etc. Reactive compatibilization of these blends has proven to be a preferred way of improving the interfacial strength at the boundaries between the two polymers and for controlling and stabilizing the morphology of the blend. This presentation will review the state-of-the-art of this technique including the relative benefits and problems of the available chemical strategies and examples of the applications of various approaches. The physics of morphology generation will be reviewed along with examples of how morphology affects performance. The relevance of recent theories of reactions at polymerpolymer interfaces and model experiments to industrial practice will be analyzed.

Extruded STYROFOAM* and ETHAFOAM* Products; Historical Perspectives
A. Paquet, S. Chum, L.C. Rubens, May 2004

STYROFOAM and ETHAFOAM are well-recognized trademarks of extruded polystyrene and polyethylene foam products that have been produced and marketed by The Dow Chemical Company for over 50 years. When Dr. Che Kao invited us to participate in this symposium he suggested that we review the early Dow research and development work which we believe provided the foundation for the long term success of Dow's extruded thermoplastics foam business. A number of books and review articles describe the science, and technology of thermoplastic foams processes and properties in detail. The philosopher George Santayana is famous for his quote: “If you do not know history you may be condemned to repeat past experiences, good or bad”. Frequently the only qualification for historical accuracy may be the statement; “I should know because I was there at the time” and this is the case for the elder co-author of this paper. He witnessed the first experiment by O. R. McIntire in the Dow Physical Research Laboratory that accidentally produced a small piece of polystyrene foam. We are still concerned with accurate recall of the origins of many ideas and contributions of numerous individuals to the successes (or failures) of innovations of DOW foam products. It is so easy to forget a key decision or minimize the importance of a key idea.

Advances in Barrier Concepts for Improved Rigid Packaging
Saleh A. Jabarin, May 2004

Poly (ethylene terephthalate) (PET) has become the material of choice for soft drinks, juices, medical and pharmaceutical applications, and some foods. Over the last ten years, efforts have intensified to improve barrier properties and hot fillable capabilities of PET in order to extend its applications to include even more food and oxygen sensitive products. These advancing technologies include new high barrier resins, coatings, oxygen scavengers, multilayer structures, heat setting and blending.A brief review of the current status of the above technologies will be presented. Specifically, a thorough discussion of experimental results will include blends of PET and other polyesters as well as blends with nylon polymers. The issues related to transesterification kinetics, optical clarity and compatibilization, strain-induced crystallization, injection molding, stretch blow molding, microstructure and container physical properties will be presented and discussed.

A New Family of Barrier Nylons Based on Nanocomposites and Oxygen Scavengers
Kris Akkapeddi, Edward Socci, Timothy Kraft, John Facinelli, Darnell Worley, May 2004

The gas barrier properties of nylon 6 could be improved significantly by a ‘passive barrier’ nanocomposite approach in which ultra-thin, nanoscale silicate platelets of high aspect ratio were incorporated via an in-situ polymerization process. The oxygen barrier properties of nylons have also been further enhanced by a novel ‘active barrier’ approach in which proprietary polymeric oxygen scavengers were melt blended into nanoscale dispersions of high oxygen scavenging efficiency. By combining the nanocomposite and oxygen scavenger technologies, a new family of barrier nylons (Aegis®) have been developed for use in multilayer packaging structures, particularly in multilayer, coinjection stretch blow molded PET bottles for extended shelf-life packaging of oxygen-sensitive foods and beverages.

Saran™ Barrier Resins – A Historical Perspective
Michael L. Mounts, May 2004

Saran barrier resins, which are copolymers of polyvinylidene chloride (PVDC), are-well known for their use in demanding barrier packaging applications to minimize the permeation of oxygen, water vapor, and odors. Less well known is the fact that Saran resins were not originally used in barrier packaging applications. As a matter of fact, the first commercial application for Saran resins was as an acid catalyst in the production of grinding wheels. Another early application of Saran resins, which was developed in the late-1930’s, was monofilament fibers. Over the nearly 65 years of their history, Saran resins, fabrication methods and markets have changed dramatically.

Polymeric Electrolyte Membrane (PEM) Nanocomposites for Fuel Cells via Direct Polycondesation
James E. McGrath, May 2004

Polymeric electrolyte membrane (PEM) based fuel cell systems for automobiles, homes, and portable power fuel cells are already important for high energy density and very good environmentally benign energy sources [1]. Currently, film forming fluorinated sulfonic acid containing copolymers are utilized primarily at 80C or lower for cost insensitive applications, such as the NASA space program. An increase in the fuel cell utilization temperature is desired for a number of reasons, including better efficiency and to improve the tolerance to impurities in fuels derived from H2, methanol, natural gas, biomass or reformed gasoline, such as carbon monoxide. New and improved mechanisms for conductivity above the boiling point of water are needed, which operate with little or no water. We have been interested in the direct copolymerization of sulfonic acid containing monomers to afford ion conducting systems such as poly (arylene ethers), including sulfones and ketones, and naphthalene dianhydride 6 membered ring based polyimides. Both random (statistical) copolymers and block copolymers based on these two major classes of materials are being investigated [2-7]. Several of these systems are surprisingly highly compatible with important additives, e.g., heteropoly acids (HPA), such as phosphotungstic acid, and zirconium hydrogen phosphate, which have potential for allowing conductivity above 100C. Highly dispersed nanocomposites have been achieved, which are possible because of specific interactions between the inorganic additive and the host copolymer, including hydrogen bonding, and dipolar interactions between the HPA and the sulfonic acid groups and/or backbone functionality. That highly dispersed HPA systems have been achieved can be demonstrated by FE-SEM, AFM and water extraction studies, and the fact that conductivity values of >0.1 S/cm are possible at temperatures approaching 140C. Excellent adhesion of the HPA to the matrix affords transparent mechanically robust

Pilot Plants of the Future
R.O. Hagerty, May 2004

Pilot plants have historically been used in polymers R&D for scale-up of new catalyst, product and process technology. Because of their essential role, pilot plants are likely to remain an important component of new technology development in the future. However, over the past several years, a limitation with conventional pilot plants has become apparent relating to an inability to detect problems of reactor operability, such as fouling and sheeting. Improvements are required in several areas including process instrumentation and mechanistic models of reactor fouling. These developments, along with improved structure-property correlations, will define the pilot plant of the future. Although physically similar to those of today, future pilot plants will feature significantly improved utilization for reduced R&D costs and faster and more reliable scale up of new technology.

The Novel STT™ Process Application with the Polymer Plant of the Future
R.A. Holl, E.A. Gulliver, A.N. McGrevy, N.H. Hall, S.A. Sojka, May 2004

This presentation will describe a unique process system called the Spinning-Tube-in-Tube, or STT™, process, which represents a paradigm shift away from the traditional approach to the processing of materials. The patented STT™ process system is a paradigm leap from volume-based to an area-based processing technology. Although applicability of the new STT™ process will be across many market sectors, this presentation will focus on applications within the polymer plant of the future. Several polymer applications will be discussed.

Hydrogenation at Supercritical Single-Phase Conditions
Magnus Härröd, Sander van den Hark, André Holmqvist, Poul Møller, May 2004

This paper gives an overview of the supercritical single-phase hydrogenation technology. It gives the basic facts from the scientific literature and the practical consequences of these facts including some possible applications to the plastic industry.The new technology can improve the product quality to levels that were impossible with the traditional multi-phase technology.The key element in the new technology is that one adds a solvent, typically propane, which dissolves both the substrate and the hydrogen. In this way a supercritical single-phase is created and the transport resistance between gas and liquid has disappeared.

A Study for Improving the Quality of a Co-Extrusion Blow Molded Bottle
M.J. Oliveira, O.S. Carneiro, R.L. Martins, May 2004

The development and production of a six-layer bottle of ethylene vinyl alcohol/polypropylene for tomato ketchup is described in this paper. The main aim of this study was the analysis of the influence of some processing parameters on the through-thickness structure of the composite. It included a first for the definition of the operating conditions leading to the required bottle structure. In a second stage, and after setting the desired bottle wall structure, the optimum welding conditions were determined. In this study, the mould temperature, the mould closing speed, and the hold time (i.e., time interval between the mould closing and the inflation) were varied according to a L9 Taguchi experiment design. The effect of the processing parameters on the morphology and properties of the pinch-off welding zone was analyzed and the best operating conditions were determined.

Analysis of Permeability and Weld Line Integrity in Multi-Layer Blow Molded Automotive Fuel Tanks
E. Grald, C. Gomez, T. Marchal, May 2004

In this study, numerical simulation is used to analyze the blow molding process of an automotive fuel tank. In a first step, 3D simulations employing a shell approximation are used to investigate the deformation of a multi-layer parison as well as the thickness variation for each layer. Next, 2D simulations are used to study the details of the welding line formation. Locally, the shear flow across the parison thickness can no longer be neglected. The position of the interface between the layers is calculated using adaptive meshing to handle the very large deformations. The influence of the rheology on the position of the interface is investigated.

Evaluating Quasi-Simultaneous and Contour Welding for use with the Clearweld™ Process
Nicole M. Woosman, Michelle M. Burrell, May 2004

The Clearweld™ process is a form of through transmission laser welding that enables welding of two clear substrates with minimal effect on the appearance. Aesthetics are especially critical in the medical and packaging industries. The Clearweld™ process can also weld colored or opaque substrates, and reduces the number of color limitations imposed in traditional through transmission laser welding.Single beam contour and quasi-simultaneous welding methods were evaluated for use with the Clearweld™ process to aid users in the selection of beam delivery methods. The welding speed, laser power, and clamping pressures were varied in order to determine the effect on weld strength, amount of collapse, residual color, and weld time. Studies were focused on PETG.

Fiber Graphics in Mold Decoration
Brown Abrams, May 2004

The purpose of this paper is to introduce and review basic elements of a newly available IMD material and technology that will impact the way many molded plastic articles will look and feel in the future. Another purpose is to inform molders who now offer IMD product about a new decoration option, a new arrow for the quiver to help create new business by expanding the range of product offerings and/or functionality.This paper is not about how to do IMD, and assumes the reader is familiar with the process. This subject has been described thoroughly in previous ANTEC papers (please refer to presentations by Jeff Applegate and Jordan Rotheiser).Fiber Graphics IMD was developed to help grow this category of decorated plastic; and in the most extreme scenarios, we are seeing a general increase in consumers’ base level of expectations about how they experience the touch and appearance of everyday plastic products and how they should perform. One example of this is: if cell phones do not need to ever slip out of your shirt pocket when you bend over, then why should they?

  Welcome Page

How to reference articles from the SPE Library:

Any article that is cited in another manuscript or other work is required to use the correct reference style. Below is an example of the reference style for SPE articles:

Brown, H. L. and Jones, D. H. 2016, May.
"Insert title of paper here in quotes,"
ANTEC 2016 - Indianapolis, Indiana, USA May 23-25, 2016. [On-line].
Society of Plastics Engineers
Available: www.4spe.org.

Note: if there are more than three authors you may use the first author's name and et al. EG Brown, H. L. et al.

If you need help with citations, visit www.citationmachine.net