SPE Library

Environmental stress cracking is the most common failure reason of plastic parts. The influence of the processing conditions has been investigated in a previous research project at IKV. Yet, it was not clear if these effects can be correlated with the molecular orientations or the residual stresses. Therefore the effects of molecular orientations and residual stresses on the ESC?resistance are analyzed. The results of these investigations are discussed in?depth.

Blends of poly(lactic acid) (PLA) and poly[(butylene succinate)-co-adipate] (PBSA) were prepared using a twin screw extruder. The morphology of the blends was examined using scanning electron microscopy (SEM). Elongational flow properties of the blends and pure components were studied. A strong strain hardening behavior was observed for PLA/PBSA blends, in which PBSA forms the continuous phase (PBSA wt% ? 50). The results of tensile test showed that even for blends containing only 10wt% PBSA, elongation at break increased significantly. By the addition of PBSA to PLA, a transition from brittle behavior (observed for pure PLA) to ductile behavior was observed.

Ytterbium Fiber Lasers are transforming laser marking of plastics. For the proper application, superior results can be achieved versus Nd:YAG and Vanadate marking lasers. However, fiber lasers are not direct replacements without thorough evaluation, and not all lasers are created equal. The metric for beam quality is M2. The smaller the M2 value, the better the beam quality, whereas M2 = 1 is the ideal laser beam. A laser with superior beam quality can be focused to a small spot size, which leads to a high energy density which is, for many applications, desirable or even required. Such is the case for many thermoplastics including POM Acetals such as Delrin. Fiber lasers are considerably less expensive to procure with zero consumables, only electricity. Further, these lasers are a “Greener” technology than YAG or Vanadate.

The purpose of this work was to perform a comparative analysis of various candidate nitrile coated fabric materials supplied by potential vendors to be used as fuel storage tanks and compare the results to the currently fielded polyurethane storage tanks. Our strategy is to utilize advanced environmental ageing methods to simulate extended weathering conditions. Our results demonstrate that the nitrile coated fabrics performed well in our evaluation. Their breaking strengths are about equal to the currently fielded urethanes and they performed comparably when subjected to environmental ageing conditions.

Introduced in 2006, INFUSE™ Olefin Block Copolymers (OBCs) have since been explored in many markets and application areas, including soft compounds. Key molecular design elements were identified as critical factors to the manufacturing of thermoplastic elastomers (TPE) with the required property balance. This paper is aimed at providing an overview of the main considerations for formulating OBCs for soft compound applications and highlights the sustainability advantage of OBC compounds relative to styrenic block copolymer compounds.

HDPE was blended with TPS and blow molded into bottles. The packaging related GHG emissions were reduced 80 percent. The method involved two extruders. The first converted the starch into TPS, while the second mixed the HDPE and TPS for a co-continuous morphology. Further dilution during the melt forming stage resulted in fine droplets of TPS dispersed throughout. The TPS was used in various layer combinations without sacrificing the appearance or performance of the bottles.

This paper will discuss published transfer efficiency of a spray applicator versus the real transfer efficiency of the spray applicator. The testing protocols used to determine the published transfer efficiency of a spray applicator will be discussed in relation to actual use of the spray applicator in a manufacturing coating process. The most common sources of material waste and the methods to reduce them to acceptable levels will be used to guide the reader to maximize the real transfer efficiency of their spray application system.

In this study, highly tubular porous chitosan/poly (DL lactic-co-glycolic acid) (PLGA) nanocomposite structures were produced via electrospinning and unidirectional freeze drying techniques. The 3D porous structure of chitosan/PLGA was characterized by scanning electron microscopy (SEM). The properties of the chitosan/PLGA nanocomposite, including porosity, water absorption, and mechanical properties, were investigated. The results showed that a highly tubular porous structure with nano-topography was formed and the compressive modulus increased greatly due to the addition of PLGA nanofibers.

Due to the increasing use of polymer-metal multi- material structures in automotive and aerospace industries, joining technology has grown in importance. Available techniques to join polymer-metal multi-material structures have been identified to be either too expensive, limited in performance or not environmental friendly. This work intends to investigate the feasibility of the new Friction Spot Joining technology on aluminum AA6181-T4 / poly(phenylene sulfide) laminate structures. Friction spot lap joints with high mechanical strength (29 MPa) were produced and investigated in terms of process temperature (average peak temperatures from 224 to 316 °C) microstructure and compared with similar joints available in the literature. Joints obtained by friction spot presented mechanical performance similar or superior to other available techniques used for joining polymer-metal structures. This is an indicative of the potential of this new technology to produce high performance metal-polymer multi-material structures.

During the last decades, the food, pharmaceutical and many other industries have seen several changes in packaging technology and applications because of new consumer demands and market trends. These drivers can be summarized as requirements for high quality, freshness and extended shelf-life of products, with easy-to-use and resistant packaging made with lighter, cheaper and recyclable materials. On the other hand, public demand and awareness for food safety has become a significant concern. This has even intensified on the recent regular outbreak of Listeria and Salmonella bacteria in various area of the world, following the consumption of contaminated meat and cheese products. The outbreak has prompted the public awareness to question food quality in stores and technological solutions that could prevent contamination and/or alert consumers may provide better public protection. Finally, the global market for materials and films used in packaging is very large. When decomposed into various segments such as controlled, active, and smart or barrier packaging, the volumes used and annual growth rates are significant in addition to other concerns such as sustainability. The performance of polymer films and multilayer packages are the result of the microstructure that is imparted to the material as a result of complex interactions between the resin and the thermo- mechanical history that it experiences during processing. This microstructure is strongly influenced by molecular parameters of the resins used (molecular weight, molecular weight distribution, branching, co-monomer type and content, etc.), their layout in multilayer structures and the additives used as well as the rheological, thermodynamic, thermal properties and the crystallization kinetics under the processing conditions. In the past, most of the studies were directed to the improvement of structural properties of films and multilayer structures (mainly mechanical: strength, tear, toughness etc...) and muc

Fiber glass reinforced engineering plastics are increasingly important construction materials in transportation, electrical and other field applications. With the use of fiber glass reinforcements, certain material properties such as stiffness, strength and temperature stability are significantly improved. Combined with the base plastics, attractive material properties are obtained making them suitable for very demanding applications. Traditional performance attributes such as mechanical and environmental properties, reductions in total part cost as well as lightweight benefits allow these materials to provide answers to more complex applications, while meeting lightweight, recyclability, food contact and other requirements. It is essential to use the right fiber glass product with the right sizing specific to the application. Sizing provides a powerful solution for many processes and performance attributes of short fiber compounds and allows the final product to meet a variety of additional requirements. In this paper, the latest developments in glass fiber reinforcement will be reviewed, focusing on some of the most important engineering plastics such as polyamide, polyester and others. It will be demonstrated how very small amounts of glass fiber sizing can be very effective in realizing performance attributes over a wide range of requirements. In addition, examples will show how glass fiber reinforcements can greatly enhance the performance of certain biopolymers.

Waste plastics usages are increasing all over the world every day. People are consuming plastics in their daily life for all necessary purposes. After they are used all plastic become garbage and its goes to land fill or incineration facilities. It’s creating environmental problem. Waste plastic can be transform into alternate or renewable energy for electricity or feedstock refinery. The thermal degradation process applied with mixture waste plastics of high density polyethylene (HDPE-2), low density polyethylene (LDPE-4), Polypropylene (PP-5) and Polystyrene (PS-6) using stainless steel reactor has been successful in converting into liquid fuel. The polymer has been selected for the experiment 100% HDPE, LDPE, PP and PS by weight. The temperature used for degradation ranges from 150-400 °C and the experiment takes about was 5 -6 hours. The obtain products are liquid fuel, light gas and black carbon residue. Various techniques such as, (Gas Chromatography and Mass Spectrometer, FT-IR and DSC) are used for obtain the analysis of the fuel purposed. GC/MS result indicates hydrocarbon compound in the produced fuel ranges from C3-C28 and also present C1-C4 light gases. Also further fractional distillation process was used to obtain different 5 (Gasoline, Naphtha, Aviation, Diesel and Fuel Oil) category liquid fuel by using different temperature profiles. All of the fraction fuels have different carbon range and contain long chain hydrocarbon like alkane and alkene and some aromatic compound.

Depolymerization of PET to high molecular weight oligomers could introduce opportunities to re-use PET waste via chemical recycling. Hydrolysis of PET in the presence of water/steam was carried out in a twin screw extruder, at barrel temperatures of 265°C and 300°C with screw speeds of 20, 60 and 200 rpm. The extruded products were characterized to determine intrinsic viscosity (IV) of samples as well as thermal properties (DSC) and rheological behavior. Proton nuclear magnetic resonance (HNMR) analysis was used to estimate carboxyl end group content. The results showed that the average molecular weight (Mw) of extruded polymer was reduced to less than 10,000 g/mol

Ever increasing energy demands, instability and uncertainty of petroleum/fossil fuel sources, and concern over global climate change have led to resurgence in the development of alternative energy that can replace fossil transportation fuel. Biomass conversion into biofuels, results a huge amount of residues or downstream products called as co-products such as distillers’ dried grains with solubles (DDGS), protein meals, crude glycerol, hemicellulose and lignin. As the production of biofuel continues to grow, surplus amounts of co-products become a critical issue and new value addition is needed for their effective utilization. A successful biorefinery begins with the productive usage of all components of biological feedstocks for value-added fuels, chemicals or materials that parallels the traditionall approach used in “petro-refineries”. Still biorefienry is risky investment, with respect to commercial benefits and finding value added uses for their co-products creates economic returns and lead to their sustainability. Thus present articles summaries the prospects of improved utilization of co-products from biofuel industries for new industrial applications.

The advent of piezo-based digital decorating enables marketers to deliver variable data, high impact graphics, and micro-targeted marketing with a single technology. Date coding, lot coding and traceability- back to the product’s origin- are now possible, enabling companies to satisfy increasingly stringent FDA requirements. And with no changeovers needed, marketers can economically create regional or store-level campaigns, delivering unique messages to minute market segments. Those messages are certain to pack a punch with near photographic quality images. Better yet, direct-to- package printing improves sustainability by eliminating labels, films and other consumable materials.

This research work explores the feasibility of ultrasonics to recycle lactic acid by depolymerizing. Post consumer PLA chopped up to 1mm2 was exposed to high power ultrasonics with water or methanol as the suspension media. The treatments were carried out in the presence of organic and ionic salts of alkali metals such a potassium carbonate and zinc chloride as the catalysts. The treatments were replicated by replacing ultrasonics with Hot water bath as the energy source. Analysis with HPLC indicated PLA to Lactic acid conversion was achieved with yields up to 90% utilizing ultrasonics. Energy calculations indicated that Ultrasonics used 30% less energy to achieve the same yield levels as achieve with hot bath technique

The causes of a drastic reduction in the service life of plastic enclosures molded from an acrylonitrilebutadiene- styrene (ABS) resin have been investigated. The mechanism and type of failure have been deduced from a detailed morphological examination of the fracture surface. Various factors responsible for a rapid failure of the enclosure have been identified. Analytical testing such as infrared spectroscopy and differential scanning calorimetry were performed to identify a specific material characteristic responsible for the failure. The results obtained during the evaluation indicated that the failure was due to environmental stress cracking, which occurred as a consequence of the presence of an incompatible chemical and assembly stress. The nature of the chemical agent was found and its effect on the properties of the ABS is discussed.

Layer multiplying coextrusion was utilized to produce a films containing polylactic acid and polyvinyl alcohol for food packaging applications. Control films and films containing 9, 25, 73 and 145 layers were produced. The emphasis of this study was to investigate the processability, morphology, barrier, mechanical and biodegradability properties of these multilayer films. The films showed stable layers, high oxygen barrier and mechanical performance that could all potentially be used in a food packaging applications.

Lifetime prediction of plastics is a very difficult proposition, but one that is becoming increasingly important as plastics are used in more demanding and critical applications. The lifetime of a plastic part is influenced greatly by many factors including the type of plastic, stress level, temperature, type of loading, and environmental conditions. All these factors make absolute lifetime prediction a nearly impossible task. However, by understanding how these factors influence plastics over time, one can begin to make educated predictions with some level of accuracy. This paper will discuss techniques that can be used to predict the lifetime of a part. A case study is given on how lifetime prediction was used to understand and ultimately solve the cracking of an industrial fan made of glass reinforced polypropylene

In the last three years the production capacities of biopolymers increased threefold. The current trend in the development of biopolymers is towards bio-based and durable materials, it veers away from biodegradable and compostable materials. As a result of this change and the significant growing market there is a bottleneck regarding the availability of information and technical data of biopolymers. The biopolymer database offers a knowledge platform about biopolymers with producer data and newly measured comparable properties. The presented comprehensive database reflects the market situation and serves as connection between manufacturers, converters and end users.