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

ANTEC®

Superhydrophobic Coatings for Encapsulation of Flexible Hybrid Electronics
K. Jaju | A. Bar | K. Puleo | J. Krantz | E. Keaney | J. Mead | D. Kazmer | B. Budhlall, May 2020

Recent advances in encapsulation process of Flexible Hybrid Electronics (FHE) provide routes to enormous application in advanced healthcare, smart layer based integrated sensor network, and digital microcontroller circuits. Stretchable/flexible encapsulation for advanced FHE devices requires new material sets and processes to ensure physical protection of any microchips in the FHE devices. Innovation in this research is creating a superhydrophobic coating that is spray coated and slot die coated on the FHE as an encapsulation process. The superhydrophobic coating is based on a cellulose acetate resin with hydrophobic silica nanoparticles and plasticizers incorporated. Here, two critical aspects are under examination; the content of plasticizer which is determined by glass transition temperature, migration and durability, and the hydrophobic silica nanoparticles which is determined by surface energy and durability. Both aspects are optimized and evaluated. Optimization of Spraying technique and its requirements is also under examination.

Surface Modifications of Cellulose Nanocrystals by Grafting Polylactic Acid via Polymerization—From Technique
Hormoz Eslami, May 2020

Cellulose nanocrystals (CNCs) have drawn significant attention in recent years owing to their specific strength, renewability, widespread availability and relatively low cost. As a result, they have gained scientific and commercial interest and are currently produced at a pilot scale in many jurisdictions for several polymer composite applications. However, their poor dispersion in typically non-polar polymer resins limits the translation of their exceptional nanoscale properties to the macroscale. In this paper,we presenteda method for the surface modification of CNC by grafting polylactic acid(PLA) onto CNCs. The dispersibility of the native and surface modified CNCs(SMCNC)in rubber latex is compared and reported here. SMCNC showed a very good dispersibility in both water and chloroprene rubber(CR)which make it a good candidate for latex composite applications.

The Advanced Study of Hybrid Molding by CAE Simulation
Yann-Jiun Chen, May 2020

Hybrid Molding is an emerging molding technology that is used in composite products. It has integrated molding characteristics, which can integrate multi-step process, save cost, reduce cycle time and make the product multifunctional. However, it is very hard to know what happened between composite sheet and melt during the process. In this study, we try to use CAE software to simulate the hybrid molding process. From the analysis results, it is possible to know the temperature change of composite sheet at any time and any place during the hybrid molding process, thereby helping to optimize the process and avoid possible problems.

The Challenge of Simulation For Ear-Flow Phenomenon In Injection-Mold Filling
Venny Yang, May 2020

Plastics applications are found in almost all areas of everyday living due to their versatility with an economically attractive choice in the manufacturing industry. Injection molding is the most common manufacturing process for producing plastic parts. However, there is a long-running problem requiring an urgent solution for the industry: to date, prior state-of-the-art predictive engineering tools have always provided unsatisfactory results regarding “so-called Ear-flow”, in which the advance of the flow front in the centre of the cavity is obviously slower than at the edges. Thus, the primary objective of this work is to simulate a reliable Ear-flow for neat polycarbonate (PC) material in injection molded disk via a new Moldex3D Flow solver coupled with the viscoelastic constitutive equation [U.S. Patent Pending in USPTO with Application No. 62/886,539 (2019)].

The Complexity of Service Life Prediction For Polyolefins In Chlorinated Disinfectants
Karin Jacobson, May 2020

Despite much effort, it is still very difficult to predict the service life of polyolefins when used in contact with the chlorinated disinfectants; chlorine, chlorine dioxide and chloramines. The actual degradation mechanism, both for the degradation of the additives and the subsequent, or in some cases parallel, degradation of the polymer, is still under debate. Also, it is not really that well known if chemical or physical properties are the most decisive in improved resistance to disinfectants. How much effect will the morphology, number and lengths of side chains, creep resistance, density, crystallinity, type and amount of stabilizer, number of tertiary hydrogens, double bonds, processing quality, solubility and diffusion rate of stabilizers, disinfectant and oxygen etc play? Since it is very difficult to change just one parameter at the time, this is quite difficult to investigate. For hot water pipes the aim is to have at least 50 years’ service life. Today the ASTM F2023 is used to test if a material will achieve this service life or not. Even if this testing is quite time consuming, with exposure times at the lowest temperature up to two years, or even longer, its validity to really predict the service life is quite questionable. The ASTM F2023 method is a pipe and materials test not a systems test and discards failures at fittings, while in fact this is often where the failure in service appears. In recent years a number of papers and presentations have been made presenting alternative accelerated testing methods and possible degradation mechanisms but very little can be found in the literature on investigations of pipes taken out of service and the correlation between the accelerated ageing with actual failures. This paper aims at describing the complexity in accelerated ageing and service life predictions of polyolefins in chlorinated disinfectants.

The Effect of Argon Plasma Irradiation On 3D Scaffolds For Bone Tissue Engineering
Katherine Wood, May 2020

Tissue engineering using 3D scaffolds is an alternative to bone repair techniques that are currently used, such as autografts or allografts for bone non-union. Plasma irradiation is used as a sterilization method and can alter the surface topography of the scaffolds. We have prepared 3D scaffolds composed of poly(lactic-co-glycolic)acid (PLGA) and nanohydroxyapatite (nHA) using thermally– induced phase separation (TIPS) and 3D-plotting (3DP) techniques. We have also performed experiments to study murine stem cell adhesion to scaffolds that have been plasma irradiated. The scaffolds that were plasma irradiated with argon gas had ~140% more cell adhesion compared to untreated scaffolds.

The Effect of Clamping Force on Product Quality: A Study on Platen Deformation
Wei-Jie Su, May 2020

The clamping force is a critical parameter to the stability of mold during injection molding process. An improper setting of the mold clamping force can adversely affect the service life of movable and stationary platens, tie bars, and molds. Thus, the clamping force is a key factor in product-quality consistency. This study bonded strain gauges to both sides of the movable platen to measure, in real time, strain changes in the platen under different clamping-force settings. The results were assessed using the corresponding cavity pressure and mold separation values to determine the molding clamping force’s effect on product quality (with respect to thickness, weight, and appearance). The findings indicated the following. (1) The mold clamping force is significantly correlated with cavity pressure, mold separation, and platen deformation. A low clamping force can cause mold separation to increase, which in turn results in greater platen deformation. (2) For the prediction of mold separation, strain gauges that are mounted on the movable platen can sufficiently replace displacement transducers that are placed within the molds. In other words, the condition inside the molds can be predicted using sensing devices outside the molds. (3) The analytic results for platen deformation and product quality indicate that an insufficient mold clamping force potentially results in excessive mold separation and platen deformation, causing flashing and an increase in product weight and thickness.

The Influence of Laser Power Variation on SLS-printed PA6 Parts and their Long-term Properties
Tobias Heckner, May 2020

In the field of Additive Manufacturing (AM), Selective Laser Sintering (SLS) is well-known as anAM technique to produce partswith comparatively high load capacity. The usage of Polyamide 6 (PA6) materials allowshigher continuous operating temperatures than Polyamide 12 (PA12) materials, which aretypicallyused forSLS. For this work,PA6 SLS specimens were printed with a high temperature SLS industry printer. The samples were aged thermo-oxidatively at different temperatures, tested mechanically and investigated with different analytical methods. The SLS processing of PA6 materials has not beenstudied sufficiently yet. The aim of this study was to deliver first contributions:the laser power energy wasvaried to identify the influence on the mechanical properties of the printed specimens andtheirlong-term properties. In addition, the material structure of the specimens wasinvestigated and the viscosity number (VN) was determined.

The Influence of Recycling On Thermotropic Liquid Crystalline Polymer and Glass Fiber Composites
Tianran Chen, May 2020

In this paper, high-performance thermotropic liquid crystalline polymer (TLCP)/polypropylene (PP) and glass fiber (GF)/PP composites were prepared by the injection molding process. Mechanical recycling of TLCP/PP and GF/PP composites consisted of grinding of the injection molded specimens and further injection molding of the granules. The influence of mechanical recycling on mechanical and thermal properties was investigated. In situ TLCP/PP maintains tensile modulus and strength during the recycling process, indicating the regeneration of polymeric fibrils at each reprocessing stage. GF/PP composite exhibits deterioration of mechanical properties after recycling because of fiber breakage during processing, which is a very common issue on reusing glass or carbon fiber reinforced composites. The experimental results reveal that the TLCP/PP composite has better recyclability than GF/PP and significantly enhances the mechanical properties of the blend.

The Use of Novel Biomaterials For Affordable Packaging
Karnik Tarverdi, May 2020

The effects of the use of biomaterials for the development of novel packaging composites have been evaluated. An increase in the amount of treated fillers improved the dispersion of the particles and consequently led to an enhancement of the mechanical properties of the materials. The composites were melt-blended using co-rotating intermeshing twin screw extrusion technology and although there can be degradation of the organic additives during extrusion processing, it did not affect the dispersion of the novel biocomposites and the biofillers.A range of techniques used to characterise these materials will be discussed, including morphology, differential scanning calorimetry, (DSC), Scanning electron microscopy (SEM), including experimental techniques likemechanical property evaluations.

Thermal Derating Factors for Fused PVC
Tom Marti, May 2020

The use of PVC pipe has been expanded in the most recent edition of AWWA C900-16. Once solely for drinking water, the AWWA C900 standard now includes reclaimed water, irrigation water, wastewater, or any other fluid compatible with nonplasticized PVC. When limited to drinking water, there is relatively little use for PVC to operate at elevated temperatures. The scope increase including industrial, raw water, geothermal, and other opportunities now make the use of PVC pipe viable so long as the pipe can meet temperature and pressure requirements. The hypothesis tested is that the present set of thermal derating factors may contain room for adjustment with the present PVC pressure pipe extrusion formulations and technology. This presentation details out the test methods used to screen and then develop derating guidance for fused PVC pipe. Screening methodology and results to validate the hypothesis are discussed. With positive results from the screening, the long term testing done to develop an alternative set of derating factors is also included.

Thermoplastic Elastomer Blend Exhibiting Combined Shape Memory and Self-Healing Functionality
Christopher Lewis, May 2020

Here we report on a polymer blend consisting of a soft-thermoplastic polyurethane (TPU) elastomer and a low melting temperature thermoplastic healing agent (Polycaprolactone, PCL) capable of repairing highly deformed cracks without the need for an external load. In this study, a blend containing 30wt% PCL (30PCL) was shown to exhibit two well-separated melting transitions thus enabling shape memory behavior. Moreover, upon heating to above PCL’s melting temperature the flow of PCL into an undeformed crack was shown to fill the crack void thus promoting self-repair. A combined healing mechanism relying on both shape memory and self-healing action was demonstrated. Through the simple action of mild heating (90C/30 minutes), fracture surfaces are brought into intimate contact through the action of shape memory recovery and subsequently healed. Healing efficiency was evaluated by comparing the tensile force restoration after healing of a highly deformed, notched sample to its behavior prior to notching. Here it was shown that the polymer blend exhibited full restoration of its originally mechanical integrity whereas the mechanical performance of pure TPU was only minimally restored (about 5%). This blend is based on thermoplastic ingredients and thus able to be converted using conventional melt processing. Applications of such blends can be extended to products prone to damage such as liner materials, protective coatings, sporting goods and shoe soles.

Towards Multi-Tiered Quality Control In Manufacturing of Plastics and Composites Using Industry 4.0
Saeed Farahani, May 2020

One of the most important topics in modern manufacturing, Industry 4.0 is quickly changing the way in which production lines in many industries operate. Industry 4.0 broadly refers to the connection of multiple manufacturing systems into a large system in which those individual systems communicate with one another. With systems connected in such a fashion, manufacturers can easily obtain actionable data from every aspect of their systems and use that data to improve their processes. Generally, Industry 4.0 technologies will vary significantly with application, and as a result, it can be difficult to develop an effective system from scratch. Given the increasing quality requirements demanded of the composites industry, particularly from automotive manufacturers, the development of an effective system to integrate data from the manufacturing process and apply it to advanced quality control methods is critical. Accordingly, we propose the concept of a multi-tiered system that combines machine data, in-mold sensors, external sensors, and a human component for use in plastics or composites manufacturing settings. Using this infrastructure, a multivariant analysis is first conducted to evaluate the advantages and limitations of each data sources in terms of determining process and part deviation. In the second study, the feasibility of developing a framework for monitoring quality of injected parts is investigated using a machine learning approach.

Transition From Ductile Failure To Brittle Fracture of High Density Polyethylene Under Creep Loading
Na Tan, May 2020

Uniaxial creep tests on notch-free specimens were conducted on unimodal high-density polyethylene (HDPE) over a wide range of stress and temperature. As expected, occurrence of ductile failure or brittle fracture was found to depend on the applied stress and temperature. In this work, a stress-time-temperature (StT) expression was established to construct the master curve of stress versus creep time to ductile failure (or brittle fracture) at a given temperature, which contains the transition between the two behaviors (commonly known as the DB transition). For the unimodal HDPE used in this study, critical stress for the DB transition was found to decrease significantly, from 11.43 to 6.50 MPa, by increasing test temperature from 296 K to 358.5 K. The corresponding time also reduced considerably, from over 560 hours at 296 K to about 6 hours at 358.5 K. In addition, critical stress for the DB transition shows a good correlation with one characteristic quasi-static stress that we reported before. Such a phenomenon sheds a light on the possibility of using a short-term test to characterize DB transition of PE pipe.

Transition Metal-Catalyzed Degradation of Polymers: Review and Future Perspectives
Andrew Worthen, May 2020

In many instances, failure of polymer-based articles is attributed to chemical interaction with metals or metallic compounds. Indeed, the stability of polymers is often modified by these species; however, their effects on the degradation of polymers are complex and influenced by many factors. This paper reviews known polymer degradation mechanisms and how metals may influence them, discusses deactivators and their role use as stabilizers in polymer formulations, provides literature-based vignettes describing example scenarios where metal-accelerated degradation of plastics may contribute to failures, and provides commentary regarding potential future areas of work in the field.

Understanding the Limitations of 3D Printed Polymers Through A Staged Screening Protocol
Jessica Hemond, May 2020

Direct printing of polymers has continued to advance with new printing technologies and engineering grade materials allowing actual additive manufacturing versus 3D printing of prototypes. Key developments include the adaptation of digital light processing (DLP) printers as well as improvements to and novel powder-based printing systems. These technologies offer the ability to bring new printed materials to the market. However, simply because a material can be printed does not mean that it will function well. With the number of printing and material advances, the need to understand possible failure modes and incorporate that knowledge into screening testing is critical. This work provides basic consideration and screening methodology to ensure that these possible material failure modes are accounted for.

Upcycling Ocean Bound PET Waste Into Durable Materials
Peter Vollenberg, May 2020

Dealing with plastics waste is a major issue confronted by the society. Single use items from water bottles to plastic packaging are major contributors to the generation of plastics waste globally. Innovative upcycling technology can transform a plastic with limited applications and a brief useful life into a different, more-durable resin with expanded potential uses and an extended lifetime. In this way, upcycling can help strengthen the circular economy and can help reduce the impact of single-use plastic applications on the environment. Using propritary de-polymerization of recycled polyester, SABIC has introduced a more sustainable polyester products family containing up to 60% recycled materials. This new PBT and its compounds have similar purity and properties as virgin resin. Hence they are drop in for many virgin PBT or compounded products. Chemistry, properties, and application for these sustainable polyester materials will be discussed. In particular, the application of ocean bound based resin in Dell computer fan housing will be highlighted.

Use of Gradually Changing Profile Shape in Extrudate Sizers for Simplification of Die Design
Mahesh Gupta, May 2020

Simulation of the flow and extrudate deformation in two extrusion dies with gradually changing profile shape in successive sizers is presented. The change in the profile shape in sizers is used to employ a simpler die geometry and then deform the extrudate in sizers to the required final product shape. Effect of non-uniform exit velocity, cooling shrinkage and shape of sizer profiles on extrudate deformation is included in the simulation. The predicted extrudate shape and layer structure is found to match accurately with those in a coextruded product.

Validation of the Virtual Lifetime Prediction Method for Elastomer Components
Simon Rocker, May 2020

In the field of mechanical engineering technical elastomers are indispensable due to their material properties. They are often used to avoid load peaks and to influence the vibration behavior of dynamically loaded systems, because of their damping characteristics. Therefore, one field of research constitutes the damage accumulation and lifetime prediction. This paper presents the validation of the virtual lifetime prediction model method, which was developed at the institute of product engineering at the University of Duisburg-Essen. The lifetime is defined as the number of load cycles till the global damage reaches the value 1. This damage is calculated by a failure criterion based on the change of a characteristic value like the dynamic stiffness degradation from a finite-element (FE) simulation. The virtual lifetime prediction method uses a combination of a damage-dependent material model (Yeoh-Model) and a nonlinear damage accumulation model (nlSAM). Both models are calibrated by means of experimental data from dynamically loaded elastomer components. The nlSAM computes the local damage for each finite element depending on material stresses and pre-damage. The dynamic stiffness degradation is a result of locally changed material properties in the FE simulation due to the damage of each element. Finally, the lifetime prediction for unknown loads and different component geometries of the elastomer is carried out, which shows good agreement with the experimental data of the same material batch.

Viscosity Considerations In Multilayer Coextrusion
Deepak Langhe, May 2020

Due to complex viscoelastic nature of the polymers, it is challenging to process multicomponent structures with uniform layer thicknesses. Although multilayered structures have been processed in a broad array of polymer materials and formulated to service a wide range of applications, a clear understanding of the effects of viscosity matching on the uniformity of the layer periodicity is not well understood. Significant work on viscous encapsulation and secondary flow patterns in the die channels affecting the layer structures has been previously reported. However, further evaluation of these effects on wide range of materials in commercial coextrusion lines has been limited. In this paper, we look to extend the initial studies of rheology in multilayered materials via layer multiplication coextrusion approaches and demonstrate preliminary results on model systems that illustrate the effect of mismatched viscosity on coextrusion multilayered polymer materials systems.







SPE-Inspiring Plastics Professionals

© 2024 SPE-Inspiring Plastics Professionals.
All rights reserved.

84 countries and 60k+ stakeholders strong, SPE unites plastics professionals worldwide – helping them succeed and strengthening their skills through networking, events, training, and knowledge sharing.

No matter where you work in the plastics industry value chain-whether you're a scientist, engineer, technical personnel or a senior executive-nor what your background is, education, gender, culture or age-we are here to serve you.

Our members needs are our passion. We work hard so that we can ensure that everyone has the tools necessary to meet her or his personal & professional goals.

Contact Us | Sitemap | Data Privacy & Terms of Use

Links

Locations

SPE US Office
83 Wooster Heights Road, Suite 125
Danbury, CT 06810
P +1 203.740.5400

SPE Australia/New Zealand
More Information

SPE Europe
Serskampsteenweg 135A
9230 Wetteren, Belgium
P +32 498 85 07 32

SPE India
More Information

SPE Middle East
More Information

3Dnatives Europe
157 Boulevard Macdonald
75017, Paris, France
More Information

Powered By SPE

SPE-Inspiring Plastics Professionals

SPE-Inspiring Plastics Professionals

SPE ImplementAM

SPE-Inspiring Plastics Professionals

SPE-Inspiring Plastics Professionals

SPE-Inspiring Plastics Professionals




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