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?
Conference Proceedings
Cavity Based Ultrasonic Resonance Monitoring in Injection Molding
Russell Edwards, Liyong Diao, Charles L. Thomas, Mike Groleau, May 2002
An ultrasonic transducer was installed on the back of the cavity plate on an injection mold such that the sound vibrations would strike the surface of the mold cavity and reflect back to the transducer. Exciting the transducer in continuous wave mode, a resonant system is produced. When the mold fills with polymer this system is damped and the resonance is changed. By monitoring these changes it is possible to monitor conditions inside the cavity during processing.
Chaotic Mixing in a Free Helix Single Screw Device
Gregory A. Campbell, Sirisha Bomma, Samuel St. John, Shaji Chempath, May 2002
Chaotic mixing in the extruder channel, obtained by the periodic motion of top and bottom walls of the channel is considered here. An analytical solution for the flow field in the extruder is used in all the simulations presented here. Using the increased degrees of freedom of the free-helix single-screw extruder, chaotic mixing can be obtained. Experimental evidence for the increased mixing of a dye in an extruder under chaotic flow field is presented.
Comarative Study of Polystyrene Foam Degradation in the Open-Air and Artificial Weathering Exposure
U. Meekum, R. Kenharaj, May 2002
Polystyrene foam(PS foam) both without and with 1% Benzoyl peroxide coated were found to be exponentially degraded within 6 months under the open-air and artificial weathering exposure. The reaction mechanism of this foam was identified as chain scission. The peroxide was effectively used as photo accelerator. The experimental data and also the statistical hypothesizes analysis using t-test with the 95% degree of confidence suggested that the data obtained from the open-air and the ones from artificial weathering exposure were analogous.
Comparing Mechanical Properties of Hot Water Piping Using Electron Beam Cross-Linking to Chemically Cross-Linked Water Piping Using a Silane Reactant
David J. Young, May 2002
The two main methods of cross-linking commercial hot water piping used in industry today are the electron beam method and the chemical method using a silane reactant. Piping cross-linked using both methods will be compared in order to determine which method produces better mechanical properties.
Comparison of Conventional Gate Freeze Techniques to Process Control Software
Jason G. Osborne, Antonio Geraci, May 2002
This paper presents the results of a study that was conducted to show whether process control software works as well or better than the part weight or cavity pressure methods in determining gate freeze.The study was done with three different molds using two materials for each mold. The molds utilized all had cavity pressure transducers close to the gate. The materials used were nylon and ABS, in order to contrast semi-crystalline and amorphous behaviors.
Compounding and Characterisation of Long Fibre Reinforced Composites Based on Flax and Polypropylene
J. Ruch, H.G. Fritz, May 2002
The compounding of long fibre reinforced composites based on flax and a polypropylene matrix has been implemented by a co-rotating, close-intermeshing twin-screw extruder. Extensive experiments have been carried out to optimise the fibre/matrix adhesion and the screw concept. Only short fibre structures could be achieved by the use of conventional screw elements, like kneading blocks or turbine mixing elements. Applying newly developed special screw elements long fibre structures as well as an optimum fibre dispersion could be reached.
Control of Gas Direction in Gas Assisted Injection Molding; Definition of Resistance to Velocity
Youngsoo Soh, Kwang-Hee Lim, May 2002
Resistance to velocity, rV , should be used as a criterion in the prediction of gas direction in gas assisted injection molding. In addition, melt resin velocity is also used in the prediction. Comparison of the velocity of fluid is especially important for more complex situations. These methods predict the gas flow direction from the knowledge of process variables such as resin flow length, cross section area of cavity, melt temperature, and short shot.
Controlling the 'Color' of Electrochromic and Electroluminescent Polymers and Devices
John R. Reynolds, May 2002
This lecture provides an overview of a group effort on NIR electroluminescence along with visible and IR electrochromism. Significant advances continue to be made in developing visible light emitting PLED’s and electrochromic polymers with visible color responses. Less effort has been directed to longer wavelengths.
Coprecipitates of Dibasic Lead Phthalate and Tribasic Lead Sulfate
Richard F. Grossman, May 2002
Coprecipitates of dibasic lead phthalate and tribasic lead sulfate tend to crystallize with the latter forming the core of a core/shell structure. The reactivity of this structure towards hydrolysis of ester plasticizers is considerably lower than that of physical blends of the basic lead salts.
Correlations between Orientation and Some Properties of Polymer Films and Sheets
A. Ajji, X. Zhang, May 2002
The orientation of biaxially stretched polystyrene (PS) sheets and polyethylene (PE) blown films were investigated. The study mainly focused on the relationships between orientation of amorphous PS and semi-crystalline PE and their shrinkage, tensile properties and tear resistance. For low orientations, it is found that the stress and strain (shrinkage in films) can be simply related to birefringence for both PS and PE. For tear properties of PE films, better correlations were observed with crystalline orientation factors.
Design of an Integrated Crash Energy Absorber for Compression Molded Bumper Beams
Anton J. Heidweiller, Frank Sparenburg, May 2002
Due to upcoming demands from insurance companies, there is an increasing need for bumper beams that take care of minimum repair costs after collision. The compression molding technique offers excellent possibilities to integrate crash absorbers into the bumper beam design. Experiments were carried out on six types of reinforced polypropylene cans. The difference in crush energy absorption of these materials was studied. The tests were carried out at crosshead speeds of 50 and 2000 mm/min.
Design, Material and Processing Effects on the Tensile Properties of Filled Polypropylene
Stephen P. Petrie, Ann M. Kirkwood, May 2002
A statistical evaluation was performed to evaluate the effects of design, material and processing conditions on the tensile properties of a filled polypropylene. Coupons were machined from injection molded plaques at different orientations and evaluated using the common tensile test. The results were compared using an analysis of variance (ANOVA). The following effects were found to be of significance in decreasing order: the type of filler, the level of filler and orientation.
Determining Cause of Failure in Plastic Parts through Microscopic Analysis
Paul K. So, May 2002
A critical first step in analyzing a plastic part failure is the examination of the cracking and the fracture surfaces. Important clues in understanding the failure mechanism are revealed by the recognition of distinctive crack pattern and characteristic fracture surface features. Several actual field failure case histories are described to illustrate the microscopic techniques and how the interaction of mechanical stresses and service environment produce unexpected failures.
Developing a Method for Rapid Design and Manufacture of Tooling
David Edwards, Robert Head Jr., May 2002
Following is the development of a method for the rapid design of bridge or short production tooling for injection molding. Starting with a product definition, part was modeled in a solid modeler. The part model was analyzed by the finite element method for performance under load and by flow analysis software to determine molding characteristics.Once the design was proven, NC code was generated to cut the cavity and runner system. The mold was commissioned and the mold cycle parameters were verified.
Developing Coaches and Mentors in Your Organizations
John R. Szymankiewicz, May 2002
Increasingly, companies are looking for leaders and not managers. Inherent in this move is the necessity for skills to motivate and develop employees. One way to cultivate leaders, as opposed to managers, and to drive positive change in an organization is to implement a coaching and mentoring system for employee development and day to day management. The next logical questions is how do you develop coaches and mentors?" This paper will provide some insight into this question and possible solutions that may work for your organization."
Development of a Data Acquisition and Control Software for an Extrusion Process
Linda Caldwell, Mark Chen, Steve Thompson, Gerry McNally, May 2002
This paper describes the development of a system control and data acquisition (SCADA) system for a Killion KTS-100 extruder. At the heart of this computer based system is LabVIEW software that facilitates the various operational requirements. Particular attention is given to the human-machine interface that allows the operator to observe the extruder's operational conditions and permit necessary operational changes to the process.
Development of a New Elastomeric Homopolymer Polypropylene
Gian De Belder, Emily Boswell, May 2002
A new elastomeric homopolymer polypropylene has recently been developed. Its unique properties are caused by the introduction of a controlled level of stereo-errors into the PP chain. This new-to-the-world material has the possibility to replace existing polymers at low cost such as thermoplastic elastomers (TPEs), flexible PVC, rubbers and other high performance polymers with the additional benefit that the polymer is completely recyclable (the only building blocks are propene!).
Development of New-Type Glass Fiber Reinforced Thermoplastics
Hiroyuki Hamada, Kaori Tsutsui, Daisuke Watanabe, Machiko Mizoguchi, Asami Nakai, Yoshinao Kobayashi, Weiliang Wu, May 2002
A new type glass fibers which are coated by thermoplastic resin, PA resin in this paper was used as reinforcements of PP injection molding materials. This fibers and surface the aments created thick interphase and also interdiffusion occurred PA and PP resin. The residual fiber length pellet was longer and interfacial shear strength was larger. Accordingly not only high tensile strength but also high impact strength injection moldings could be achieved by this new type glass fiber.
Direct Sheet Extrusion and Thermoforming of TPO Compounds
M. Malkani, J. Soneta, J.L. Mead, S.A. Orroth, May 2002
This research explores the development of thermoplastic olefin compounds through direct sheet extrusion and their thermoforming characteristics. A number of high rubber content formulations were compounded on a twin-screw extruder and formed directly into sheets via a gear pump. Sheets produced by direct sheet extrusion were thermoformed using a several thermoforming techniques, and the effect of material properties on thermoformability was evaluated for high draw applications. A thermoforming process window was developed for each compound and processing method.
Dispersed Solids Melting Model in Single Screw Extrusion
H. Potente, J. Pape, May 2002
In opposite to most screw designs the geometry of some single screw concepts lead to a break-up of the so called solid bed. Therefore the well known Tadmor-Model is not capable to describe this melting behavior. First approaches for such a model were already made by several scientists. Unfortunately these models assuming some simplifications having a strong effect on the accuracy. Thus a new dispersed solids melting model was developed assuming less simplifications. It shows good agreement with experimental results.
.jpg)
.jpg)
.jpg)
.jpg)
