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.
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Conference Proceedings
Linear Polyphenylene Sulfide (PPS) for Thermoplastic Composites
Harsh Bhagat, September 2008
PowerPoint Presentation at ACCE 2008.
Long Glass Fiber-Polypropylene Light Weight Instrument Panel Retainers & Door Modules
Matthew Marks, September 2008
PowerPoint Presentation at ACCE 2008.
Composite Liftgate Ductility Performance
Peter Foss, September 2008
The FMVSS 301R Fuel System Integrity Test requirements on closures as well as field experience have increased demand on the liftgate performance. The energy imparted to the liftgate structure in this test configuration is difficult to absorb with inherently brittle composite materials. This report documents the load-displacement response of several reinforced composite liftgates. The liftgates were evaluated with a static test designed to simulate the deformations experienced in a rear 70% offset deformable barrier crash test.
Fatigue Life Prediction of Short Fiber Reinforced Plastic Components
Robert Wahlmueller, September 2008
In automotive engineering the development of light weighted structures is very important to save fuel and so to reduce the pollution. Therefore the usage of new materials like fiber reinforced plastics is very attractive even for dynamically loaded parts. Nevertheless there is still little knowledge about the fatigue behavior of fiber reinforced plastics. So it is difficult to make an optimum design according to the divergent requirements on weight and strength. Some research works have been already done by BMW [1 2] and others [3-5].
DIGIMAT Multi-Scale Modeling: The Technology & Software Tools for a Predictive Development of Reinforced Plastic Parts
Roger Assaker, September 2008
PowerPoint Presentation at ACCE 2008.
Constitutive Modeling of Polymer Composites made from LBL Manufacturing Technique
Harish Iyer, September 2008
PowerPoint Presentation at ACCE 2008.
Hybrid Laser Welding of Polymers
Chris Korson, September 2008
Hybrid laser plastic welding is a process to enhance the limitations of conventional laser plastic welding in order to provide a joining technology for large three dimensional parts. Because of existing tolerances of injecting moulded parts it is necessary to provide a maximum gap-binding capability of the welding process. The poor capability of bridging gaps between the joining partners at contour laser welding and long cycle times are still limiting the range of applications. At hybrid welding the energy that is being deposited into the material is provided by a semiconductor laser and a secondary source of radiation e.g. a halogen lamp at the same time. A hybrid welding head provides one focal point of the laser and a secondary radiation source. The polychromatic emission spectrum of the halogen lamp causes a volumetric absorption of the incident radiation in the upper joining partner. This leads to a more symmetric temperature distribution around the welding plane and different lateral heat fluxes compared to conventional laser welding processes. This paper will discuss the effects of the larger temperature field and will disclose the benefits compared to conventional laser welding. Experimental results are showing that a larger process window and faster feed rates are possible. Compared to conventional laser welding the seam strength is in spite of a faster feed rate conspicuously improved. The gap-binding ability is rising with a hybrid welding system threefold. In consequence of the secondary radiation and the modified temperature distribution there are less residual stresses because the ability of the material to creep is stopped. The hybrid welding process is comparable to a laser welding process and a tempering of the material at the same time.
Bond-Line Read-Through Investigation for Composite Closure Panels: Initial DOE Results
Kedzie Fernholz, September 2008
Bond-line read-through (BLRT) is a distortion in a Class “A” surface that has no impact on the structural performance of automotive body panels yet it diminishes a customer’s perception of the quality of a vehicle. The root causes of this distortion are poorly understood. When a panel is discovered to exhibit BLRT in production the most straightforward solution is to increase the thickness of the outer panel–essentially adding weight for appearance. The Automotive Composites Consortium Joining Working Group (ACCJWG) has a multi-year project targeted at developing a better understanding of the causes of this distortion so that OEMs can use minimum thickness body panels and still meet customer expectations for surface appearance quality. In the first phase of this project the ACCJWG developed a tool for quantifying the visual severity of this distortion. The ACCJWG then partnered with Meridian Automotive Systems to complete a series of experiments to understand the material and process variables that influence BLRT and to determine how to minimize the severity of this distortion without increasing the thickness of the outer panel. The format and results of the first two experiments of this series will be discussed. The first experiment was a screening experiment to determine whether any of the eight factors evaluated impacted the severity of BLRT. The factors evaluated in that experiment were type of substrate degree of cure of the SMC type of adhesive consistency of bond-line thickness pattern used to apply the adhesive distortion in the inner panel temperature at which the adhesive was cured and type of electric bonding nest. Six factors were found to have a statistically significant effect on BLRT severity although the effect of three of the factors may have been confounded by an uncontrolled covariate. Two factors were found to not impact BLRT severity. The temperature at which the adhesive was fixture cured was found to be the factor with the greatest impact on B
The Use of Cohesive-Zone Models to Analyze the Behavior of Adhesive Joints
M.D. Thouless, September 2008
The use of adhesives in structural automotive applications will rely on an effective understanding of how they behave under crash conditions and how to model their performance. Historically the strengths of adhesive joints have been modeled by two distinctly different approaches-strength-based criteria and energy-based criteria. Cohesive-zone models form a natural and self-consistent approach to bridge these two approaches within a single framework. In systems for which the adherends remain elastic cohesive-zone models allow many well-known concepts of interfacial fracture mechanics and its energy-based failure criteria of toughness to evolve. In systems for which the adherends deform in a plastic fashion cohesive-zone models provide a framework for analysis in a regime that cannot be addressed by fracture mechanics. Under these conditions the behavior of a joint may be controlled by the strength of the adhesive the toughness of the adhesive or by a combination of the two parameters depending on the details of the geometry and properties of the materials. An practical issue is then how to determine in a relatively simple fashion the two cohesive parameters that can be used in mixed-mode applications. This is of particular interest for automotive applications where a methodology for designing adhesive joints for energy-management during crashes needs to be developed.
Renuva Soy-Based Polyol RIM for Automotive Exterior Applications
Dow Automotive & Magna/Decoma International, September 2008
There are many formative trends in today’s OEM composite marketplace which are driving the investigation and development of alternative feedstocks from natural or renewable resources in the plastics industry such as environmental sustainability reduced dependence on crude oil and the high cost of petroleum-based derivatives. This paper will describe the development of a novel soy oil based polyol (under the RENUVA™tradename) which has technological advantages in terms of odour physical properties compatibility and processability in polyurethane application over existing soy-based polyol. The paper will further describe the development partnership undertaken by The Dow Chemical Company and Polycon Industries (a division of Magna International) to utilize this “green” polyol to develop a Reaction Injection Moulded (RIM) polyurethane formulation suitable for painted exterior applications. The paper will outline the development aliterations done to accomplish this goal and to maximize the soy-based polyol content in the RIM composite for physical property and processability optimization. The paper’s conclusion will demonstrate the viability of a 50% soy-based polyol solution to meet the processability paintability and physical property specification of a current Original Equipment Manufacturer (OEM) RIM program through direct comparison of extensive trial work done on series production fascia tooling at Polycon. The paper will extend this development work into potential opportunities for the RIM polymer involving exterior composite applications for heavy equipment or agricultural machinery where natural resource feedstocks would have clear market desirability.
Banana Fiber Composites for Automotive & Transportation Applications
Lina Herrera-Estrada, September 2008
The purpose of this work was to establish and optimize a process for the production of banana fiber reinforced composite materials with a thermoset suitable for automotive and transportation industry applications. Fiber surface chemical modifications and treatments were studied along with processing conditions for epoxy and eco-polyester banana fiber composites. Flexural tests show that banana fiber/eco-polyester composites have a higher flexural strength and modulus due to improved fiber/matrix interaction. Environmental tests were conducted and the compressive properties of the composites were evaluated before and after moisture absorption. The resulting banana fiber/epoxy composites were found to yield a flexural strength of 34.99 MPa and compressive strength of 122.11 MPa when alkaline pretreated with improved environmental exposure resistance. While the non alkaline pretreated banana fiber/polyester composites were found to yield a flexural strength of 40.16 MPa and compressive strength of 123.28 MPa with higher hygrothermal resistance than pretreated fiber composites with the same matrix.
Chopped Glass & Natural Fiber Composites Based on a Novel Thermoplastic Epoxy Resin Matrix
Craig Chmielewski, September 2008
Composites of chopped glass and natural fibers based on a novel thermoplastic epoxy resin (TPER) matrix are introduced. Polymerization of substantially linear polymer chains based on epoxy resins produce an amorphous thermoplastic that is amenable to blending high loadings of reinforcing fillers which offer both high strength and stiffness. For example chopped glass fiber reinforced TPER composites offer similar room temperature tensile and flexural properties as glass filled polyamide 66 but are limited in their upper use temperature by TPER’s glass transition temperature of 90 °C. TPER is especially well suited to accepting high levels of natural based fillers such as wood flour and cellulose pulp. Natural fibers can be compounded into TPER at temperatures low enough to avoid thermal decomposition and yet result in composite mechanical properties of 3 to 4 times the flexural strength and 2 to 3 times the modulus of standard natural fiber-polyolefin blends. These new TPER based composites have properties and an appearance that make them candidates for a variety of automotive applications.
Natural Fibers Plastic Composites for Automotive Applications
Jay Amarasekera, September 2008
The use of natural fibers in composite plastics is gaining popularity in many areas and particularly the automotive industry. The use of natural fibers in polymers can provide many advantages over other filler technologies and areas of application appear limitless. The automotive industry is currently shifting to a “green” outlook as consumers are looking for environmentally friendly vehicles. Natural fibers are a renewable natural resource and are biodegradable which is an important characteristic for components that must be disposed of at the end of their useful life. They are recyclable and can be easily converted into thermal energy through combustion without leaving residue. Among the natural fibers with potential application as reinforcement for polymers curauá fiber is one that recently received special attention from researchers. Curauá is a plant from the Bromeliad family cultivated in the Brazilian Amazon region. The fiber is extracted from its leaves providing a high mechanical strength over traditional fibers like sisal jute and flax. We have developed thermoplastic composites using either curauá fiber or wood flour. These materials provided a lighter weight product with good physical properties and unique surface aesthetics. This paper reviews the properties of these bio composites in comparison with glass and mineral filled products. The products were tested in some automotive applications and the results will be discussed.
Case Study: Tough Low-Mass Class A SMC
Edward Zenk, September 2008
Fuel is one of the single largest expenses for fleet owners and it accounts for nearly 50 percent of a truck’s operating cost. Lowering a vehicle’s weight is a proven method of increasing operational economy whether in fuel consumption or additional capacity; and in the trucking industry this is a pressing need. A unique collaboration amongst a commercial fleet owner a heavy truck manufacturer and their suppliers achieved a cost-effective and significant weight savings through the use of tough low mass Class A sheet molding compound (SMC). This paper/presentation describes the customer’s objectives issues encountered and commercial results achieved with the new technology.
Introduction of Proven Marine Composite Process for the Commercial Vehicle Market
Fred Buck, September 2008
At Commercial Vehicle Group our drive for new and better processes and products never ends. One of our latest investments is in composite molding for interior and exterior trim components and systems. Through an exclusive agreement with VEC Technology LLC CVG is applying a composite closed mold process which has been used extensively in the manufacture of recreational boats to the unique needs of the commercial vehicle/heavy duty truck industry. The parts for heavy truck are very large in size while the part volumes are moderate and this situation presents interesting opportunities. Our molding process bridges the gap between the limitations of open-face molding and the higher costs associated with other forms of composite closed molding. In this presentation I will show you our Composite Molding Process from Concept and Design to the Mix Plant to the Application of Gel and Barrier Coats to the Laying of the Fiberglass to Molding & Part Creation to finally Routing Sanding and Application of Additional Parts with Structural Adhesive to the Customer.
An In Depth Study of Texture Characteristics & Their Affects on Texture Performance
Phil Maniscalchi, September 2008
Automotive and material suppliers have struggled for years with trying to produce quality textured hard plastic parts with correct gloss levels and good mar resistance. Many times suppliers are at the mercy of the textures being chosen by OEM design studios. Some textures that are visually appealing may not perform well for gloss and/or mar. In the past little was known as to what specific characteristics led to these performance limitations. The purpose of this paper is to identify the specific characteristics of automotive textures and how these characteristics affect mar and gloss on molded plastic parts. By analyzing these characteristics designers will be able to create or modify textures that are both robust and aesthetically pleasing. Topics to be discussed include identifying contributing texture characteristics discussing how these characters can be manipulated to improve performance and recommendations will be made as to how ideal textures should be developed in the future.
Rapid Manufacturing & Continued Development of Highly Stressed Fibre-Reinforced Plastic Parts: Motorbike Dash Assembly Made by Windform XT and SLS Technology
Stewart Davis, September 2008
The follow paper illustrates one of the latest high-tech RP and RM applications made by Laser Sintering Technology and WINDFORM® materials on a 125GP Honda racing motorbikes. In particular it describes the benefits coming from the use of WINDFORM material and the Rapid Manufacturing technology to produce a special Dashboard to host the motorbike’s electronic system developed internally by CRP Racing (the racing department of CRP Technology) which had to be light and stiff at the same time and above all the new design of the Dashboard support developed for the 2008 season in order to ease its substitution when crashed and saving some money as well. Completely different from the original one a new support was created in several modular parts to allow a good cost saving.
Film Transfer Technology Advancements for Composites
Ara Asadorian, September 2008
The composite industry has been driven to reduce the cost of composite parts. The Film Transfer Technology allows the manufacture to increase the value of manufactured parts. The Film Transfer Technology expands the manufacture's capability to coat protect and produce products with printed images during the production process. For example a manufacturer can immediately produce a wood grain panel at no capital cost. The Film Transfer Technology is applicable for SMC BMC Infusion and open mold manufacturing processes. The coating provides protection to the end product and image in chemical abrasive and outdoor environments. Thus the Film Transfer Technology increases the compostie manufacturer's capability to sell decorative products within the Marine Transportation and Architectural markets at a higher value.
NanoStructured Polymer Membrane for Fuel Cell Application: Computational NanoTechnology Approach
Seung Soon Jang, September 2008
We investigate a new molecular architecture in which water-soluble dendrimers are grafted onto a linear polymer for application to polymer electrolyte membrane fuel cells (PEMFC). Using computational nanotechnology we examined the nanophase-segregation and transport properties in hydrated membranes with this new architecture. In order to determine how the nature of the linear polymer backbone might affect membrane properties we considered three different types of linear polymers: poly (epichlorohydrin) (PECH) poly (styrene) (PS) and poly (tetrafluoroethylene) (PTFE). Each of these are combined with the second-generation sulfonic poly aryl ether dendrimer to form PECH-D2 PS-D2 and PTFE-D2. Our simulations show that the extent of nanophase-segregation in the membrane increases in order of PECH-D2 (~20Å)< PS-D2 (~35Å) < PTFE-D2 (~40 Å) at the same water content which can be compared to 30~50Å for Nafion and ~30 Å for Dendrion at the same water content. We find that the structure and dynamics of the water molecules and transport of protons are strongly affected by the extent of nanophase segregation and water content of the membrane. As the nanophase-segregation scale increases the structure in water phase the water dynamics and the proton transport approach those to those in bulk water. Based on the predicted proton and water transport rates we expect that the PTFE-D2 may have a performance comparable with Nafion and Dendrion.
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