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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Various topics related to sustainability in plastics, including bio-related, environmental issues, green, recycling, renewal, re-use and sustainability.
Fracture Mechanical Characterization Of Non-Virgin Pipe Materials
For accelerated characterization of slow crack growth (SCG) properties of modern polyethylene pipe grades the Cyclic Cracked Round Bar Test has been developed. While many investigations on polyethylene are available with this test, only few studies have been published yet with other relevant pipe polymers such as polypropylene or polyvinyl chloride. Moreover, the increased use of non-virgin polymers for structural applications based on reprocessed or recycled resources is becoming a topic of increasing importance. The current paper presents an investigation of the general applicability of the Cyclic Cracked Round Bar Test to the mentioned polymers with a special focus on the sensibility to non-virgin materials. On the one hand the results show that this test can be used for accelerated SCG characterization of all materials. On the other it is demonstrated that the SCG resistance of non-virgin polymers is significantly lower than for virgin pipe grades.
Fracture Properties Of Hdpe Exposed To Chlorinated Water
HDPE is often used in applications that include both structural and environmental loads. In this study, the effect of an oxidative environment on HDPE mechanical performance is evaluated. Thin 75 micron HDPE samples are exposed to 5ppm chlorinated water at 70C for up to 1250 hours. Changes in polymer morphology as a function of exposure time are evaluated and compared with fracture and tensile test data. FTIR data show an increase in the carbonyl group after 250 hours of exposure, while GPC data show a 20-50% loss in molecular weight after 500 hours exposure. The decrease in molecular weight is associated with shortening of the higher molecular weight chains. Essential work of fracture data and strain at break show significant loss in ductility for exposed samples. This set of data demonstrates the correlation between morphology changes and embrittlement in unimodal HDPE.
From Recycled Tires To Plastic Parts: Micronized Recycled Rubbers In Thermoplasitc Polyolefins
Micronized rubber powders (MRPs) have shown superior compatibility in TPOs and excellent elastomeric properties. However, it requires efforts to explore the use of MRPs in useful products and a few challenges need to be addressed. In this study, MRP-filled TPEs were compounded at various loading ratios and the effect of sizes of MRPs was investigated. In addition, the surface details of injection molded parts were studied and induction-heated molding were implemented to improve the surface finish for various applications. Finally, multiple conventional plastic processes were explored and injection-molded parts made out of MRP-filled compounds were demonstrated to discover more potential applications.
Fully Biobased Degradable Plastic With Insecticide Functionality
Natural insecticide, pyrethrum, and insect repellent DEET were added to poly(lactic acid) (PLA) fibers via extrusion and spraying. GPC analysis showed that the addition of DEET caused an increase in depolymerization with the increase of DEET concentration. Contact Irritancy Assay (CIA) showed that DEET-treated PLA fabrics caused the lowest percentage escape response with an escape frequency of 33.3 ± 3.3%. This was followed by the extruded natural pyrethrum-treated PLA fabrics with an escape frequency of 80 ± 6.3%. PLA fabric spray-treated with natural pyrethrum caused an escape frequency of 98.3 ± 1.7%. All treated fabrics caused repellency.
Get The Wear Out
Most would agree that the mold is the heart of the molding process. From those that make them to those who use them, we all want them to last for as long as they were designed. A lot of work goes into striving toward that goal: good design, proper metallurgy selection, configuration, coatings, etc. With all that having been taken into account, why clean the mold with traditional methods that may wear out the parting line and shut-offs? This paper will demonstrate that cleaning tooling with dry ice is a safe, effective and non-abrasive way to clean common injection molds. It will provide molders, not only a way to extend the asset life of the tool, but also to improve quality, increase productivity, lower costs and improve environmental quality. This paper will focus on the first benefit of maintaining the expected life of our molds. Today, high-dollar and often complex molds, are run and maintained in varying degrees of skilled molding shops and tool rooms. Some of the cleaning methods still be utilized can contribute to tool wear.
Hierarchical Micro/Nanostructures Of Poly (Lactic Acid) Scaffolds For Medical Applications
Although tissue engineering has shown great advances in recent years, creating proper mechanical properties and cell growth microenvironments is still challenging. In this study, electrospun poly (lactic acid), PLA, nanofibrous membranes were hot embossed to develop 3D hierarchical micro/ nanostructures. Human umbilical-vein endothelial cells (HUVECs) were then cultured on these structures. The hot-embossed membranes exhibited not only superior mechanical properties (the tensile strength was 7.01 ± 0.18 MPa and the tensile modulus was 166.91 ± 15.54 MPa), but also better cell viability as evaluated through a CCK-8 assay and fluorescent dye. The grating arrays of the micropatterned fiber mats encouraged the HUVECs to proliferate. The approach proposed here—combined electrospinning and hot embossing—has great potential for biomedical applications, including for use as polymer scaffolds in tissue engineering.
Highly Viscous Polyamides Made Of Cast Polyamide 6 Recyclates
Cast polyamide 6 is anionically polymerized from ε-caprolactam. Its good properties are mainly caused by the higher molecular weights, compared to standard polyamide 6. Because of sprues and post-processing, a larger amount of scrap is produced. This scrap is typically incinerated without sufficient use of its high quality properties.However, cast polyamide 6 also offers great potential for material recycling, particularly if its high molecular weight can be retained. As cast polyamide decomposes during processing as well, it is necessary to add some additives during compounding. It is the aim of the presented work, to recycle cast polyamide to highly viscous materials. This is done by adding a polyester-modified wax and a carboxylic acid. It can be shown that it is possible to get materials having viscosities of up to two magnitudes higher compared to a typical extrusion polyamide.The high molecular weight of cast polyamide can be maintained or even outperformed. While Young’s modu-lus and tensile strength remain unchanged, the used wax causes some crosslinking of the polyamide and thus also leading to higher impact strength.
How Plastics Helps To Conquer The New Challenges Of Vehicle Electrification
How plastics helps to conquer the new challenges of vehicle electrificationbyMelanie Mennigke; LG Chem - Key Account ManagerWerner Posch; Dräxlmaier Group - Material ManagementThe need for zero emission solutions is steadily increasing and OEMs are currently developing battery electric vehicles with a focus on providing emission-free transportation, combined with lowest total cost of ownership. The main challenges for these vehicles include: range; cost and weight.Electric vehicles are no longer a trend but an established fact. In order to make the correct decision on which technological approach – BEV (battery electric vehicle) or REEV (range extended electric vehicle) - best meets the requirements of the market, the manufacturers specific boundary conditions and economic aspects have to be balanced with a multidisciplinary approach. The development of alternative drive vehicles is driven by both consumer and government demand. Consumers want fuel-efficient, low-emission vehicles, but they do not want to pay a premium to drive a more sustainable car. Governments want improved fuel economy and low emissions, and go as far as using manufacturer tax credits and consumer write-offs to incentivize alternative drive vehicle development. However, for a solution to be truly sustainable, it must be economically feasible, as well as environmentally sound.As the market grows for hybrid-powered and electric vehicle technology, plastics play an ever more important role to help reduce carbon emissions and dependence on petroleum. The challenges of using plastics in electric vehicle technology are: • Use of plastics instead of aluminum and steel for weight reduction• Use high-performance polymers and elastomers to integrate components and functions — this miniaturization reduces space and improves packaging.• Improve battery pack performance with flame-retardant and thermoplastic materials.• Prevent electrical arcs and sparks in connectors with thermoplastic materials that meet 650-volt system requirements.• Provide electromagnetic compatibility (EMC) The presentation includes proved plastics solutions for challenges described above. Examples of developed and already in serial production electric power trains (High-voltage battery systems, power electronics,...) to identify the right plastics for design and serial production which fulfil requirements such flame resistance, EMI shielding, weight reduction,... So that automakers can build hybrid and electric vehicles that meet consumer and environmental needs.
Impact Of Plastics Packaging On Life Cycle Impacts In The U.S. And Canada Substitution Analysis
Prepared by Franklin Associates for the American Chemistry Council, this study expands upon the 2014 substitution analysis that used life cycle assessment methodology to assess the energy consumption and greenhouse gas (GHG) emissions of six general categories of plastic packaging produced and sold in North America relative to alternative packaging. The updated analysis includes other life cycle impacts - including but not limited to solid waste generation and consumptive water use, as well as updated energy and GHG results. This presentation will answer the question: if plastic packaging were replaced with alternative types of packaging, how would life cycle impacts, such as energy consumption, water use, and waste generation, be affected?
Improving Long Term Corrosion Resistance In Electronic Applications
Improving long term corrosion resistance in electronic applications Electronic components have invaded the automotive environment with increasingly complex designs and functionality. In addition, the location and environment of these components continues to drive the requirements to higher performance materials. The combination of exposure to electrical potential, moisture, elevated temperature and environmental salt can affect the performance of electronic components. DuPont has developed a line of “EF” Electrically Friendly resins which will help reduce the risk of long term corrosion or performance degradation in aggressive environments.
Influence Of Processing And Formulation On The Properties Of Pp-Pet-Blends
The aim of this work was to investigate the effects of the composition and processing on the properties of PP-PET blends with and without compatibilisation. As the processing routes blend production via a co-rotating twin screw extruder as well as single screw extruder were chosen. We found, that it is possible to compatibilize PP-PET blends via the addition of maleic anhydride grafted PP. This effect can be seen from the morphology of the samples as well as from mechanical properties. In twin screw extrusion, the application of vacuum degassing shows additional property improvement due to the condensation of PET. The compatibilizer is also effective in single screw extrusion, but the effect is lower due to the missing degassing options. Nevertheless, the compatibilized blends are stable and the results show, that such mixed plastics, which can also be found in waste streams, can be reused when being properly processed.
Innovation In Mature Markets: Understanding Global Trends Across The Value Chain Key And Accelerating Development
Markets trends of cost reduction, sustainability & down-gaging drive the need for new and improved products. Development of such products requires a look across the entire value chain – an Asset to Market look. An emerging trend in the materials space is related to collection and management of data that enables knowledge creation. Management of this data and the knowledge generated is critical to accelerating research. This talk will focus on what is required for rapid product development, launch and knowledge transfer across a global organization to sustain market leadership. Key examples will be presented and will cover these trends.
In-Situ PP/PET Nano-Fibrillated Composites: The Effect Of Viscosity Ratio On Fibrillation And Foaming Behavior
It is widely accepted that the manufacturing of high expansion PP foams with fine cell morphology is a challenging task due to the low melt strength and the weak rheological behavior of the linear polypropylene. In this study we present a novel method to manufacture high cell density, large expansion microcellular foam through nano-fibrilation PP/PET composites. Various studies have been conducted to improve the processability of linear PP foams. Until now, the most successful industrial approach is using the branching PP as it expressed the strain hardening response and the increased melt strength behavior. However, the commercial price of branching PP resins are still doubled or even tripled comparing with linear PP resins, which dramatically limits the branching PP’s applications. Inducing chemical cross-linking is proven to be another effective way to improve the melt strength of PP. However, the cross-linked structure causes difficulty in recycling PP resins. Furthermore, the cross-linking reaction is not evenly initiated throughout the matrix rendering non-uniform cell structure in the final foam product. Implementing inorganic/organic filler is another alternative route for enhancing the foamability. PP reinforced with those fillers has higher viscosity and better elasticity at melting state. Nonetheless, the well-recognized challenging issue is to achieve well distribution and dispersion of nano-size fibers inside the polymer matrix. Because of the large surface to volume ratio, the nano-fibers tend to agglomerate. The well-established methods usually requires complex experimental conditions and normally involves dealing with chemical hazards. By implementing nano-fibrillation technology, all above mentioned draw-backs were overcome. The nano-fibrillation technology is used to manufacture polymer-polymer fibril composite in this study. The nano-fibrillation technology can generate high aspect ratio nano-fibrils uniformly dispersed inside the polymer matrix. The processing can be briefly summarized as: (i) blending immiscible polymer matrix (A) and polymer reinforcement (B) to make polymer (B) dispersed in spherical shape (the melting temperature of polymer B should be at least 30oC higher than polymer A); (ii) applying large deformation on the polymer extrudate by either hot stretching or cold stretching; (iii) carefully choosing a temperature between the melting temperature of polymer A and polymer B to melt the composite without damaging the fibril morphology of polymer B. In this study, three kinds of PPs with different viscosity are reinforced with PET nano-fibrils via melt spinning. The study shows that the high viscosity PP is preferred to generate low diameter nano-fibrils (~200 nm) in a wide concentration range; while the diameter of fibrils in low viscosity PP decreased with raising PET concentration. The oscillatory shear behavior is studied by comparing the storage modulus (G’) and phase angle (tanδ) of the non-fibrillated and fibrillated samples. Differential scanning calorimetry and birefringence optical microscope were employed to study the crystallization kinetics of PP/PET fibril composites. The rheological properties and crystallization kinetics were significantly improved with the presence of PET fibrils. Crucially, benefit from the strengthened rheological behavior and crystallization kinetics, the batch foaming of PP/PET nano-fibril composite is able to product a high cell density polymer foams.
Investigation Of The Effect Of Stabilizer System, Medium And Temperature On The Fatigue Crack Growth Resistance Of Polypropylene For A Proper Material Selection
For a proper selection of materials for solar-thermal applications, the failure behavior of various polypropylene (PP) grades was investigated by fatigue crack growth (FCG) experiments. The four tested material grades differed in their stabilizer system. To determine the effect of environmental media (chlorinated water with a chlorine content of 5 ppm, air and deionized water) and elevated temperatures (95°C and 80°C), cracked round bar specimens were tested on an electro-dynamic testing machine equipped with a special desigend media containment.Tests at all environmental conditions revealed a significant influence of the stabilizer systems on the FCG resistance. While at all conditions the stabilization with a hindered amine light stabilizer resulted in the best FCG behavior, depending on the environmental loading different PP grades showed the worst FCG resistance. In terms of media dependence of the crack growth behavior, for all PP grades, the best and worst FCG behavior were obtained in deionized water and chlorinated water, respectively. Results received from tests under two different temperatures showed that the FCG resistance decreased with increasing temperature in all tested environments and for all PP grades.
Leveraging Advanced Edge Analytics For Improved Fault Detection In Discrete Manufacturing Processes
IntroductionMultivariate analytics data monitoring systems provides a significant fault detection improvement over typical SPC type, or Univariate, solutions currently being used in the discrete manufacturing process industry to allow manufacturers to eliminate manual and visual quality inspection and to achieve real-time process release or "lights out" manufacturing operations.Problem StatementCurrent method of Univariate SPC process control typically utilized by discrete manufacturing process industry is not fully capable to detect quality issues caused by combinations of signals acting jointly on a system. Process engineers also must make manual adjustments to process limits to accommodate for slowly drifting processes, or caused by environmental effects, incoming material issues, and equipment wear. How can the user be certain these limits adjustments will not result in quality issues?Solution The SenseLink™ QM system builds a multivariate model around the optimized process with an acceptable processing window, established from a design of experiments (DOE). The system generates application-specific & automatic limit setting, reducing the reliance on expert process engineers and operators tweaking process knobs causing variations to the process. New data is then compared in real-time to the alarm limits developed by the model. The multivariate alarms are then triggered if the new data is off-spec, sending a reject signal to a part containment device for real-time part containment.OverviewThe SenseLink™ QM system is a data acquisition system with a multivariate data analysis engine that was developed for any industrial manufacturing process, and used with manufacturing processes or secondary operations to provide improved process understanding. Each cycle is multivariate analyzed in real-time to provide variable contribution charts, which highlight process trends not seen by UVA (Univariate). Real world case studies have proven this solution effective.ConclusionUsing a Multivariate fault detection system in your industrial manufacturing processes will provide the highest level of in-process fault detection available along with contribution details which provide an understanding of your process not attainable from traditional SCADA and SPC approaches.MKS InformationAndrew Wilson | Product Marketing Specialist | Automation & Control Solutions | MKS Instruments, Inc.firstname.lastname@example.org | Cell: 512.962.3598www.mksinst.comhttps://www.mksinst.com/product/product.aspx?ProductID=203
Low Birefringent Cellulose Acetate Propionates For Plastic Display Lens Covers
The fusion of electronics with glass and plastics to create smart surfaces with a harmonious luxury ambiance is creating a flurry of development activity which is changing the driver/passenger experience in the transportation industry. Merging human machine interface (HMI) displays, controls, and knobs with other decorative plastic components is being driven in part by the desire to reduce/eliminate distractions (safety) in addition to bringing a stylish atmosphere which increases consumer satisfaction. For displays, the desire to move away from the typical two dimensional 7- inch rectangular shape towards larger and different shapes (curved and non-rectangular) becomes a challenge in and of itself because glass has a lower design freedom for forming curvature and tempered glass is considered costly. Plastic covered displays are easier to produce 3 dimensional shapes via either injection molding or vacuum lamination of films, and their light transmitting abilities are similar to glass. As is observed with some glass display surfaces, certain plastics are also prone to birefringence caused by molded in stress which contributes to poor distinctness of image and reading legibility. Choice of polymer and glass surfaces for integrated HMI displays in instrument and door panels, or seat backs is the center of attention given the vast number of requirements of the automotive industry. This paper will focus on the characteristics of bio-based, low birefringent cellulose acetate propionate (CAP) as potential HMI-lens covers in comparison to other clear polymers.
Mechanical And Rheological Characteristics Of Pp/Pet Blend With Maleic Anhydrite And Jute Fibre
This paper presents an investigation of the effect of mixing natural Jute fibre and Maleic Anhydrite compatibilizer with recycled Polypropylene (PP) and Polyethylene terephthalate (PET) blends. Recycled plastic has a significant contribution to reduce the environmental issues and encourage the economic benefit. PP and PET polymers are commonly used in the industrial fields, however, they are immiscible and it is difficult to be blended. Two different PP & PET (65/35 and 78/22 v/v %) samples have been blended with 0.5% wt (2 g) Jute fibre and 5% wt (20 g) Maleic anhydride (PP-g-MAH). The mechanical mixing has been done by using twin-screw extruder to get pellets of PP/PET/jute/Maleic Anhydrite, which were used to make test samples with injection moulding machine. The comparative result shows that blend of PP/PET with and without any addition of Maleic anhydride and Jute fibre has enhanced tensile and flexural properties significantly.
Mechanical Behavior And Anaerobic Biodegradation Of A Poly(Lactic Acid) Blend Containing A Poly(Lactic Acid)-Co-Poly(Glycolic Acid) Copolymer
Poly(lactic acid) (PLA) is arguably the most well-known biodegradable plastic. However, its degradation behavior is far from ideal. The goal of this work is to prepare PLA blends that exhibit accelerated biodegradation performance whilst retaining adequate mechanical properties. To accomplish this a copolymer consisting of poly(L-lactic acid) and poly(glycolic acid) (PGA) structural units was synthesized and subsequently melt blended with a commercially available PLA homopolymer. The anaerobic degradation behavior of the polymer blend was greatly enhanced as a result of the incorporation of 20 wt% of the copolymer. A moderate change in mechanical properties including a 20% reduction in stiffness and strength and an 80% increase in elongation to break was also observed.
Mechanical Reinforcement With Cellulose Filaments
Kruger Biomaterials proprietary cellulose FiloCell™ is obtained from peeling the filaments from wood fibres using a mechanical process that uses no chemicals or enzymes. Since the peeling is gentle, very thin filaments are obtained while the original length is preserved. The filaments are further surface treated without modification of the chemical structure in order to prevent hornification (agglomeration due to strong hydrogen bonds) and to produce 99.7% dried, re-dispersible filaments. The resulting filaments are renewable, non-toxic, have high surface area, high aspect ratio, mechanical strength and low density. Given these properties, cellulose filaments are a unique multifunctional lightweight filler which can be added to polymer resins as a reinforcing agent and can potentially replace glass fibers.In this work, cellulose filaments are melt-blended into thermoplastics LDPE, Nylon 6 and TPU. Cellulose filaments are shown to effectively increase the Young’s modulus and the strength of all polymer matrices. The mechanical enhancement is increased with loading level of cellulose filaments. It is shown that no compatibilizing agent is needed in order to improve the interaction between the hydrophilic filler and the hydrophobic matrix. Moreover, although one drawback of natural fiber is its thermal degradation at high processing temperature, we managed to successfully compound our cellulose filaments with nylon 6 which has a processing temperature of 230˚C. In LDPE resin, at the same weight, cellulose filaments outperform glass fibers in both tensile strength and tensile modulus. In comparison with other natural fibers, cellulose filaments have the advantage of higher mechanical performance and lower water absorption.
Mining The Value From Oil Sands Tailings Ponds
In Canada, the cleaning cost of 340 billion gallons of oil sands tailings ponds is estimated to be over $27 billion. There is a need for cost-effective technologies for removal and recovery of oil from these ponds. Previously, we reported foams application for absorption and adsorption of crude oil from water. This works aims to develop effective method for foam reuse and oil recovery to improve the benefits of the treatment process. The polyester polyurethane (PESPU) foam with pH-responsive wetting properties and crude oil were used to assess the effectiveness of mechanical compression, pH-swing method, and chemical wash method. The mechanical compression is a simple, environmental friendly, and easy to implement method. This process was effective in recovery of the absorbed oil, where the oil uptake mechanism is reversible superhydrophobic forces and pore filling. However, for adsorbed oil recovery it was less effective. According to pseudo-second-order kinetic model, the oil droplets were adhered to the sponge surface by physical forces. As a result, mechanical forces were weak in shearing-off the thin oil film. Based on pH-responsive wetting property, the oil adsorption was effective at acidic conditions. Therefore, the oil recovery was performed at basic conditions by introducing new “pH-swing” technique. This method produced minimal waste and sustainable, but materials reusability declined to ~70% within three cycles. Finally, chemical wash method was applied to recover the adhered oil from the surface. According to surface chemical displacement principles, a solvent with appreciably low surface tension than the foam and similar molecular structure the crude oil was used to wash the sponge at ambient conditions. Due to enhanced solubility and flowability, the crude oil was readily recovered from the foam surface. The cleaned foam as well exhibited over 99% efficiency over multiple reuses. Our finding show that the foam is a promising solution to remediate detrimental oil sands tailings and for recovery of the residual crude oil from water leading to environmental and economic benefits.
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