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
Keyword/Author:
After Date: (mm/dd/yy)  
 
Sort By:   Date Added  ▼  |  Publication Date  ▼  |  Title  ▼  |  Author  ▼
= Members Only
Failure Analysis and Prevention
Fourier Transform Infrared Spectroscopy in Failure and Compositional Analysis
Jeff Jansen, January 2022
Fourier transform infrared spectroscopy (FTIR) is a fundamental analytical technique for the analysis of organic materials. It provides critical information in the evaluation of polymeric materials, including material identification, contamination, and degradation. The webinar will present a fundamental understanding of the technique and the following topics will be covered:
  • Theory of Infrared Spectroscopy
  • Test Result Interpretation
  • Application to Polymeric Materials
    • Material Identification
    • Contamination
    • Degradation
  • Sample Preparation Supplementing FTIR With Other Techniques
  • Cases Studies
Thermal Dependency of Plastics
Jeff Jansen, December 2021
Because of their molecular structure, polymeric materials have different properties compared to other materials, like metals. Due to their viscoelastic nature, polymeric material properties our temperature dependent. As the temperature is increased, the polymer chains are further apart, there is more free volume and kinetic energy, and the molecules can slide past one another and disentangle more easily. The physical properties and performance of polymeric materials, such as strength, stiffness, and impact resistance, are highly dependent on the temperature at which the stresses applied. Over a temperature range, polymers will pass through key transitions, such as beta transitions and glass transitions, as well as softening and melting. Understanding the implications of these transitions and their correlation to molecular structure is useful in material selection and avoiding premature failure. The goal is that this webinar will provide:
  • A better understanding of how plastic mechanical properties change as a function of temperature.
  • The ability to recognize that there are both lower-end and upper-end temperature limits for polymeric materials.
  • Familiarity with the testing that can be utilized for evaluating the effects of temperature on plastics, as well as tests that are commonly used but provide very little useful information.
Outline
  • Viscoelasticity
  • Temperature
  • Thermal Transitions
  • Thermal Performance
  • Elevated Temperature
  • Low Temperature
  • Understanding Continuous Service Temperature Limits
Plastic Datasheets: What They Do and Don't Tell Us
Jeff Jansen, November 2021
UL Prospector lists tens of thousands of different plastic resins. When tasked with material selection, 99% of us turn to the typical property data sheet. What are the issues with the single point numbers listed on these datasheets? Why does sole reliance on this information often lead to failed product? What should we be doing instead? Selecting the proper material for an application requires the right data. While plastic project have evolved over the past 50 years, the data we are given has not evolved. This webinar will present the deficiencies of the information presented on plastic data sheets, and suggest what is really needed.
Failure of Plastics Session 2
Jeff Jansen, October 2021
This 2-part webinar series will cover a considerable range of topics important in understanding, diagnosing, and preventing plastic component failure. The most efficient and effective approach to plastic component failure is by performing a systematic failure analysis. Someone once said, “if you don’t know how something broke, you can’t fix it”, and this certainly highlights the importance of a thorough understanding of how and why a product has failed. This webinar series will introduce the attendees to information they need to gain this understanding.
  • The material covered will include: Essential knowledge of why plastic components fail, 

  • The five factors affecting plastic part performance, 

  • The process of conducting a failure investigation and methods for understanding how and why a product has failed, 

  • The importance of ductile-to-brittle transitions and their role in plastic component failure, 

  • The major plastic failure mechanisms, 

  • Failure analysis case studies
The webinar series will focus on practical problem-solving techniques and will utilize case studies to illustrate key aspects of plastic failure and prevention. Participants will gain a better understanding why plastic components fail, and how to avoid future failures by applying the knowledge learned.
Failure of Plastics Session 1
Jeff Jansen, October 2021
This 2-part webinar series will cover a considerable range of topics important in understanding, diagnosing, and preventing plastic component failure. The most efficient and effective approach to plastic component failure is by performing a systematic failure analysis. Someone once said, “if you don’t know how something broke, you can’t fix it”, and this certainly highlights the importance of a thorough understanding of how and why a product has failed. This webinar series will introduce the attendees to information they need to gain this understanding.
  • The material covered will include: Essential knowledge of why plastic components fail, 

  • The five factors affecting plastic part performance, 

  • The process of conducting a failure investigation and methods for understanding how and why a product has failed, 

  • The importance of ductile-to-brittle transitions and their role in plastic component failure, 

  • The major plastic failure mechanisms, 

  • Failure analysis case studies
The webinar series will focus on practical problem-solving techniques and will utilize case studies to illustrate key aspects of plastic failure and prevention. Participants will gain a better understanding why plastic components fail, and how to avoid future failures by applying the knowledge learned.
Polypropylene: Commodity Resin, I Don't Think So
Jeffrey A. Jansen, June 2021
Polypropylene is often referred to as a “commodity resin”, however, is this really the case? Polypropylene is a versatile thermoplastic that can be processed through a variety of processing techniques. It is utilized in a wide range of applications, including packaging, automotive, infrastructure, appliances, healthcare, and electrical. Its wide use is based upon several key strengths, including:
  • Good chemical resistance
  • Good electrical insulation properties
  • Flexural strength and modulus
  • Relatively low coefficient of friction
  • Readily available and relatively inexpensive
The implication of the interchangeability of polypropylene resins does a disservice to the complexity of this material and the plastic industry in general. The properties of polypropylene are highly dependent on molecular weight and molecular weight distribution, crystallinity, type and proportion of comonomer and the tacticity. Hopefully, at the conclusion of the webinar, attendees will
  • Gain an understanding of the general properties of polypropylene.
  • Have more insight into how the molecular structure of polypropylene determines its performance properties.
  • Appreciate the diversity of polypropylene.
Integration of Polycarbonate Thermoplastic in LED Lighting
Nicolas J. Sunderland | Jim Lorenzo, May 2021
Thermally conductive (TC) polycarbonate was utilized as aluminum metal replacement in LED lighting luminaires, along with transparent, diffusion, and reflective polycarbonate thermoplastics in order to describe a light weight, design-friendly, cost efficient part. To assess suitability of the TC polycarbonate, the part was subjected to thermal testing. Results showed very similar thermal characteristics as aluminum.
Designing for Six Sigma (DFSS) - A Systematic Approach to Robust Plastic Part Design
Vikram Bhargava, May 2021
Designing for Six Sigma (DFSS) - A Systematic Approach to Robust Plastic Part Design To design and manufacture today's complex plastic components, product designers are under tremendous pressure to produce robust designs at a minimum cost and in the fastest possible time. Leading author David Wright wrote in his book titled “Failure of Plastics and Rubber Products” that design issues account for almost 20% of product failures. The fact is that many errors that manifest themselves as material, tooling or processing can also be attributed to design issues. Conventional plastic flow simulation does not necessarily help diagnose and avoid common design issues. Decisions made at the design stage impacts manufacturing quality, product cost, and delivery lead times. Taking a proactive approach by including Six Sigma philosophy upfront into the early design stage can help develop high quality, profitable products eventually bringing sustained value to customers and markets. The Paper will discuss the Design for Six Sigma (DFSS) philosophy and best practices and tools for its incorporation into new plastic product development. This will include: • Understanding the DFSS concept and popular methodologies such as DMAIC and DMADV • Learning how to use DFSS Methodology in early part of plastic product design lifecycle • Applying DFSS techniques and available simulation and DFM tools for successful implementation
Analysis of the State of the Art of Technical Drawings of Plastic Molded Parts Regarding Tolerances
Anja Falke | Friedrich-Alexander | Martin Bohn | Tim A. Osswald, May 2021
The plastic-specific material properties are often not taken into account in the specification of technical drawings of injection molded parts. As a result, tolerance requirements are specified, that are too tight and sometimes even impossible to manufacture, which result in high production expenses. To avoid this, it is necessary to coordinate the functionally required accuracies of plastic components with the technical possibilities available for injection molding production.
In this paper a systematic analysis of drawings from practice is used, to show the current state of the art regarding geometric product specification and tolerance assignment of plastic molded parts. In addition to the quantification of the number of specified features, the unambiguousness of the product specification is assessed. Beyond that, the degree of accuracy of the tolerance requirements is quantified and the manufacturing feasibility is checked in accordance with ISO 20457 in order to then determine the resulting production expense that is necessary to achieve the required tolerances. It is proven that for almost a fifth of the plastic parts tolerance requirements are specified that are not feasible to be produced in the injection molding process. Additionally, it is found that all drawings examined do contain ambiguously specified features, that do not allow for an unambiguous verification.
The Most Frequent Design Flaw That Leads to Part Failure
Paul J. Gramann, Ph.D., P.E., May 2021
The topic presented in this paper is not new. There are numerous reasons why sharp transitions should not be present in a plastic part. However, the number of failures that are occurring at sharp transitions is still very common. In most cases, they can easily be avoided by simply removing metal from the mold to make a smooth transition. This paper will review where most of these transitions are being found, and why they are common in critical parts. A tensile testing study was performed to better understand the effect of geometric transitions. Two cases studies are given showing why the sharp corners can significantly reduce the lifetime of a plastic part.
Fused Filament Fabrication Feedstock Characterization via In-Line Rheology
A.R. Colon | D.O. Kazmer | A. Peterson, May 2021
An instrumented hot end has been developed to monitor the pressure in Fused Filament Fabrication, and is used as an in-line rheometer to characterize the viscosity of an acrylonitrile butadiene styrene (ABS) material. Additional analysis was performed on the transient pressure data to consider compressibility effects and nozzle drool. The range of flow rates was identified at which the pressure in the hot end was most stable. Stabilization time given compressibility effects was also evaluated.
Lifetime Prediction of Continuous Fiber-Reinforced Plastics Based on Nonlinear Damage Accumulation
Simon Rocker | Reinhard Schiffers | Lars Gerdes | Daniel Hülsbusch | Frank Walther, April 2021
Full Title: LIFETIME PREDICTION OF CONTINUOUS FIBER-REINFORCED PLASTICS BASED ON NONLINEAR DAMAGE ACCUMULATION AND FINITE ELEMENT SIMULATIONS Abstract: This paper presents an approach for lifetime prediction of fiber-reinforced plastics based on nonlinear damage accumulation. Already established damage accumulation laws, such as Palmgren-Miner, are to be modified with nonlinear parameters in order to characterize the damage evolution of fiber-reinforced plastics in a more accurate way. For this purpose, cyclic investigations were carried out on glass fiber-reinforced polyurethane with quasi-isotropic layer setup to determine basic mechanical characteristics. The stiffness-based characteristic values, recorded to develop the simulation model, are generated from hysteresis loops, which are also used to calibrate the material model. The experimentally determined stiffness degradation is converted into a damage curve by assigning the first measured value to degree of damage 0 and the failure value to degree of damage 1. Therefore, a hysteresis loop for each degree of damage between 0 and 1 is present, so that a damage dependent stress-strain ratio can be determined and transferred to the material model cali-bration. In addition, a characteristic damage development is derived from the damage curves, whereby the stress level and the influence of sequence can be taken into account for a nonlinear damage accumulation model on global level. Based on the global findings an algorithm is presented that transfers those to the local level in finite element simulations. This approach provides the fundamentals for a lifetime prediction of fiber-reinforced plastics with varying fiber orientations under cyclic loading.
Developing Photopolymerizable Acrylate Resin Formulation for Impact Modified 3D Printed Thermosets
Chinmay Saraf | Amy Niu | Alan J. Lesser,, April 2021
This contribution focuses on engineering photopolymerizable acrylate resin formulations for a superior fracture energy absorption of 3D printed acrylate thermosets. Herein, we report a polydimethyl siloxane-based block copolymer as an impact modifier, compatible with the UV curing process, which undergoes reaction induced phase-separation during the 3D printing process to form a rubbery phase sufficient for enhanced impact properties. A systematic investigation of the effect of concentration of the impact modifier on the morphology of rubbery domains and fracture toughness was conducted. Results show that at an optimum concentration of 15 wt.% and particle size of 57 nm, an order of magnitude improvement in the fracture energy release rate is realized. Fractographic analysis of the impact modified thermosets using optical microscopy indicates the presence of significant plastic deformation in an otherwise brittle material. Notably, the engineered acrylate thermosets, at an optimum concentration, exhibit similar improvements in the impact properties irrespective to the print layer thickness and independent of the crack orientation with respect to the printed interphase. Detailed investigation of the failure mechanisms for impact modified thermosets show that the block copolymer diffuses to the interphase during the 3D printing process, resulting in preferential localization of the impact modifier near the print interphase resulting in an isotropic enhancement of the fracture toughness.
Fractography of Glass Reinforced Plastics
Jeff Jansen, April 2021
The goal of a failure analysis is to identify the mechanism and cause of the component failure - to distinguish how and why the part broke. A fractographic examination is an essential part of this investigation, particularly in identifying the failure mode. Cracking occurs as a stress relief mechanism as a response to the exertion of stresses on a component. Glass fiber reinforced plastics offer enhanced mechanical properties, particularly strength and stiffness over unfilled materials. Their use is widespread in a wide variety of applications where mechanical integrity is essential. However, fractographic evaluation of these materials often presents a challenge due to the confounding effect of the fibers. The fibers can obscure the fracture surface features arising from:
  • Type of material and formulation constituents;
  • Type of applied forces (tensile, compression, shear);
  • Magnitude of forces;
  • Frequency of forces (continuous, intermittent, rapidly applied);
  • Environmental effects (temperature, presence of chemical).
This presentation will explore the challenges unique to glass fiber reinforced materials and techniques that can be used to gain the maximum information from these fracture surfaces.
Thermal Analysis of Plastics
Jeffrey A. Jansen, March 2021
Thermal analysis is an important group of tests used in the analysis of plastics and other polymeric materials. It consists of a family of well-established techniques that evaluate material properties as they change with temperature, time, and ambient environment under conditions of thermal programming. The results of thermal analysis tests provide qualitative and quantitative information about the material being evaluated. In particular, this information is important to address plastic failures or in characterization of the material composition and physical properties. The upcoming webinar on thermal analysis will introduce the four primary techniques:
  • Differential Scanning Calorimetry (DSC)
  • Thermogravimetric Analysis (TGA)
  • Thermomechancial Analysis (TMA)
  • Dynamic Mechanical Analysis (DMA)
The webinar is designed to introduce the techniques to the attendees so that they may get a better understanding of how the techniques can be used to evaluate plastic materials and solve problems. No single thermal analysis technique is best suited universally, but together they provide essential data for the characterization of plastics materials. This presentation will review thermal analysis techniques and their application to plastic problem solving through case studies. The webinar will be a practical treatment of the techniques, and the focus will be on how the techniques can be utilized to better understand polymeric materials. At the end of this presentation you will:
  • Gain insight into the different types of thermal analysis techniques
  • Recognize which technique is best suited to obtain the information you need
  • Understand how thermal analysis can be used to characterize the composition and properties of plastic
Environmental Stress Cracking
Jeffrey A. Jansen, February 2021
Environmental stress cracking (ESC) is the leading cause of plastic component failure, and a recent study suggests that 25% of plastic part failures are related to ESC. If you deal with plastic components, then “Environmental Stress Cracking of Plastics” will provide you with information that will enhance your understanding of the interaction between chemicals and plastic resins, with the goal of preventing part failure. ESC is a solvent-induced failure mode in which a plastics crack through contact with a chemical agent while under stress. The webinar will be presented from a practical viewpoint with actual case studies to illustrate the ESC mechanism and explain plastic performance. Topics covered during this session include:
  • Introduction to ESC
  • How plastics fail
  • Explanation of the ESC failure mechanism
  • Generalizations related to chemical interaction with plastics
  • ESC resistance testing used to evaluate plastic/chemical compatibility
  • Case Illustrations of some common solvent-based failure modes
At the end of this presentation you will:
  • Have a better understanding how chemicals effect plastic components.
  • Recognize potential situations where ESC failure could occur in your parts.
  • Be able to design a chemical resistance program to evaluate plastic/chemical combinations.
The Consequences of Ductile-To-Brittle Transitions in Plastics
Jeffrey A. Jansen, December 2020
Thermoplastic resins are utilized in many applications because of their unique property set, including their ductile response to applied stress. This ductility is associated with the viscoelastic nature of polymers and is attributed to their unique molecular structure. In spite of that inherent ductility, most plastic components fail through one of the many brittle fracture modes. Experience through conducting thousands of plastic component failure analyses has shown that less than 5% were associated with ductile overload. The remainder represent brittle fractures of normally ductile materials. Thus, within evaluations of plastic component failures, the focus of the investigation frequently turns to identifying the nature of the ductile to brittle transition. This relatively brittle response to stress is evident through the examination and characterization of the fracture surface morphology. There are numerous factors, associated with material, processing, design, and service conditions that influence a ductile-to-brittle transition within plastic materials. These include:
  • Temperature
  • Stress Concentration
  • Chemical Contact
  • Molecular Weight
  • Degradation
  • Filler Content
  • Contamination
  • Poor Fusion
  • Strain Rate
  • Time Under Load
  • Crystallinity
  • Plasticizer Content


This item is only available to members

Click here to log in

If you are not currently a member,
you can click here to fill out a member application.

We're sorry, but your current web site security status does not grant you access to the resource you are attempting to view.




spe2018logov4.png
  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