Download or read book Controlling Cellular Structure in Thermoplastic Foam Injection Molding Influence of Processing and Mold Technologies written by Mike Tromm and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Some Critical Issues for Injection Molding written by Jian Wang and published by BoD – Books on Demand. This book was released on 2012-03-23 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is composed of different chapters which are related to the subject of injection molding and written by leading international academic experts in the field. It contains introduction on polymer PVT measurements and two main application areas of polymer PVT data in injection molding, optimization for injection molding process, Powder Injection Molding which comprises Ceramic Injection Molding and Metal Injection Molding, ans some special techniques or applications in injection molding. It provides some clear presentation of injection molding process and equipment to direct people in plastics manufacturing to solve problems and avoid costly errors. With useful, fundamental information for knowing and optimizing the injection molding operation, the readers could gain some working knowledge of the injection molding.

Download or read book Microcellular Injection Molding written by Jingyi Xu and published by John Wiley & Sons. This book was released on 2011-01-06 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the most important aspects of microcellular injection molding with applications for science and industry. The book includes: experimental rheology and pressure-volume-temperature (PVT) data for different gas materials at real injection molding conditions, new mathematical models, micrographs of rheological and thermodynamic phenomena, and the morphologies of microcellular foam made by injection molding. Further, the author proposes two stages of processing for microcellular injection molding, along with a methodology of systematic analysis for process optimization. This gives critical guidelines for quality and quantity analyses for processing and equipment design.

Download or read book SPE ANTEC 2000 Proceedings written by Spe and published by CRC Press. This book was released on 2000-05-05 with total page 1214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 2 of the conference proceedings of the SPE/Antac on 'Materials', held on the 711 May 2000 in Orlando, Florida, USA.

Download or read book Foamability of Thermoplastic Polymeric Materials written by Suprakas Sinha Ray and published by Elsevier. This book was released on 2021-09-24 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foamability of Thermoplastic Polymeric Materials presents a cutting-edge approach to thermoplastic polymeric foams, drawing on the latest research and guiding the reader through the fundamental science, foamability, structure-property-processing relationship, multi-phase polymeric materials, degradation characteristics of biodegradable foams and advanced applications. Sections provide detailed information on foam manufacturing technologies and the fundamental science behind foaming, present insights on the factors affecting foamability, cover ways of enhancing the foamability of various polymeric materials, with special focus on multi-phase systems, discuss the degradation of biodegradable foams and special morphology development for scaffolds, packaging, acoustic and super-insulation applications, as well as cell seeding studies in scaffolds. Each application has specific requirements in terms of desired properties. This in-depth coverage and analysis helps those looking to move forward with microcellular processing and polymer foaming. This is an ideal resource for researchers, advanced students and professionals interested in the microcellular processing of polymeric materials in the areas of polymer foaming, polymer processing, plastics engineering and materials science. Offers in-depth coverage of factors affecting foamability and methods for enhancing the foamability of polymeric materials Explores innovative applications in a range of areas, including scaffolds, acoustic applications, packaging and super-insulation Provides a comprehensive, critical overview of the state-of-the-art, possible future research directions, and opportunities for industrial application

Download or read book Polylactide Foams written by Mohammadreza Nofar and published by William Andrew. This book was released on 2017-09-18 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polylactide Foams: Fundamentals, Manufacturing, and Applications provides an introduction to the fundamental science behind plastic foams, polylactic acid) and polylactide foaming, giving designers tactics to replace traditional resins with sustainable and biodegradable materials. The book then delves deeper into the technology behind PLA foaming, such as PLA/gas mixture characteristics, solubility, interfacial tension behaviors and crystallization kinetics of various types of PLA and their compounds. The foaming behaviors and mechanisms of various types of PLA and PLA compounds are extensively analyzed and discussed through different manufacturing technologies, namely extrusion foaming, foam injection molding and bead foaming. Interest in Poly(lactic acid) and PLA foams is extremely high – particularly as a potential replacement for styrenic resins – and the price of PLA resin is lower than ever before. This biopolymer has significant potential to improve the sustainability of the plastics industry. Polylactide Foams have a range of potential applications, such as in construction, packaging, insulation, biomedical scaffolds, and others. However, processing and performance of PLA are not at the same level as other non-biodegradable resins. Introduces the concepts behind foaming, poly(lactic acid) and PLA foaming Supports further research and development in PLA foams by covering the state-of-the-art in different manufacturing and processing methods Provides practical guidance for materials scientists and engineers in industry looking to replace traditional polymer resins with a sustainable, biodegradable alternative

Download or read book Manufacturing Highly Expanded Thermoplastic Polyurethane Foams Using Novel Injection Molding Foaming Technologies written by Hrishikesh Ashokrao Kharbas and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis summarizes the studies undertaken to achieve the objective of manufacturing injection-molded thermoplastic polyurethane (TPU) foams with high density reductions, desir-able microstructures, and customizable properties. TPU foams are quickly gaining market share in numerous applications in the sports and recreation as well as manufacturing industries. This is because TPU foams can be easily manufactured in a variety of densities, hardnesses, and mechanical properties, ranging from highly resilient to highly compressible foams, with different processing methods, such as injection molding, casting, and extrusion. Typically, TPUs are being foamed to a minimum density of 0.40 g/cm3 (400 kg/m3). It is the aim of this thesis to expand the understanding and processing knowledge of manufacturing TPU foams with densities as low as 0.25 g/cm3 (250 kg/m3), while maintaining desirable microstructures. It is also an aim of this thesis to develop a novel process to control foam properties locally in injection molded TPU foams. In the journey toward achieving the aforementioned objectives, five studies were conducted and are presented in this manuscript. An experimental study evaluating the CBA and PBA foaming of TPU has been undertaken. A novel foam injection molding process using CO2 + N2 as co-blowing agents to exploit the synergistic benefits of co-blowing agents was also evaluated in this study. It was found that PBA foaming can be vastly advantageous for foaming TPU by enabling large reductions in bulk densities without the harmful effects of chemical residue. This novel process of using co-blowing agents yielded the lowest bulk density while achieving the highest cell density and finest average cell size. To resolve the issue of low melt strength at higher temperatures, which leads to cell coalescence and undesirable microstructures, the use of a physical cross-linking agent was considered. It was proposed that a physical cross-linking agent could increase the melt strength of the TPU at higher temperatures, thus enabling aggressive foaming strategies to give enhanced density reductions. It is shown here that extremely low-density TPU foams of bulk density 0.16 g/cm3 (160 kg/m3) can be achieved consistently. In Chapter 3, nanoclay as a reinforcing filler was employed to increase the melt viscosity and to trigger heterogeneous nucleation in the TPU matrix, thereby improving the foamability of TPU while achieving a homogenous microstructure with low average cell size and high cell density. It is generally known that TPU's rebound resilience values decrease with decreasing foam density. It was observed that rebound resilience values could increase significantly if a tunable alignment of microcells can be produced within the part, even while reducing bulk densities. Through the action of mold inserts, the expanding microcells will thereby stretch and align with the intercellular TPU walls and individual molecules in the direction of mold opening. With aligned microcells, the softness of the foams improved significantly, while achieving lower hysteresis loss ratios or energy loss (dissipation). In Chapter 5, a core retraction mold capable of increasing cavity volume was designed and manufactured to enable further study of the phenomenon observed in Chapter 4, with better parameter control. Polypropylene (PP) was the material chosen to validate the capabilities of the mold and the applicability of this technology to materials other than TPU. Core retraction was used with the conventional micro¬cellular injection molding (MIM) process to foam thick PP parts with high density reductions of 30% and 55%. The cavity volume was modified by chang¬ing the retraction distance, which resulted in varying den¬sity reductions. The lowest densities were achieved with a core retraction-aided microcellular injection molding (CR-MIM) process, the results of which could not have been achieved by the conventional MIM process alone. It was shown that the CR-MIM process yielded a better microstructure and a higher tensile modulus than the conventional MIM process. Use of core retraction also yielded more consistent densities and tensile properties at different distances from the gate location. It was shown that by using delay times and holding pressures, cell nucleation and cell growth can be delayed to a more suitable time and melt temperature. Mechanical and energy absorption properties of TPU foam can be varied with the density and microstructure of the foam. In Chapter 6, a new process is developed using core retraction and out-of-mold foaming to develop injection molded parts of varying cross-sections with varying mechanical properties. It was shown that, using this process, very low density foams of less than 0.25 g/cm3 can be produced while maintaining uniform and good microstructures. It was also shown that this technology can be effectively used to vary microstructures, densities, and mechanical properties within an injection molded part locally, depending on the application. In summary, the aforementioned approaches have helped to advance the knowledge of manufacturing TPU foams and other regular thermoplastics with customizable microstructures and mechanical properties for various specific applications.

Download or read book Physical Foam Injection Molding written by Hartmut Traut and published by Carl Hanser Verlag GmbH Co KG. This book was released on 2024-05-06 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than half of all injection molded plastic parts can be produced more cost-effectively and with better tolerances using foam injection molding compared to traditional compact injection molding. For the part designer, the focus is on the functionality of the molded part, not on the plastic-compatible design, which is precisely what compact injection molding requires. This book describes the necessary fundamentals of physical foam injection molding, clearly illustrated by means of detailed, industrially proven examples to show the technology’s potential. Machine and mold technology are also explained in detail, and polymers suitable for the process are discussed. The focus is always on the question of whether the potential of physical foam injection molding has already been exhausted or whether it is emerging as a second standard process alongside compact injection molding. The experienced authors make it possible to look beyond the end of one’s nose. The reader can see which plastic parts can be converted from compact to foam injection molding, and is encouraged to rethink the part design. With this book, specialists are able to examine an application for their own company and analyze it with regard to its economic implementation. However, the book also shows the clear limitations of this technology. Content: Foam Injection Molding and its Different Process Variants Definition and Characteristics of Physical Foam Injection Molding Design Guidelines for Foamed Components Polymers for Foam Injection Molding Process Simulation Mechanical Fundamentals of the Foam Injection Molding System Mold Technology Application Examples: Automotive/Household/Packaging/Medical

Download or read book Open cell Foaming with Injection Molding written by Raymond Kar Man Chu and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Polymeric Foams written by S.-T. Lee and published by CRC Press. This book was released on 2022-05-18 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymeric Foams: Innovations in Technologies and Environmentally Friendly Materials offers the latest in technology and environmental innovations within the field of polymeric foams. It outlines how application-focused research in polymeric foam can continue to improve living quality and enhance social responsibility. This book: Addresses technological innovations including those in bead foams, foam injection molding, foams in tissue engineering, foams in insulation, and silicon rubber foam Discusses environmentally friendly innovations in PET foam, degradable and renewable foam, and physical blowing agents Describes principles as well as applications from internationally recognized foam experts This work is aimed at researchers and industry professionals across chemical, mechanical, materials, polymer engineering, and anyone else developing and applying these advanced polymeric materials.

Download or read book Encyclopedia of Chemical Processing written by Sunggyu Lee and published by Taylor & Francis US. This book was released on 2006 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collecting information of vital interest to chemical, polymer, mechanical, electrical, and civil engineers, as well as chemists and chemical researchers, this "Encyclopedia "supplies nearly 350 articles on current design, engineering, science, and manufacturing practices-offering expertly written articles on technologies at the forefront of the field to maximize and enhance the research and production phases of current and emerging chemical manufacturing practices and techniques.

Download or read book Polymer Nanocomposite Foams written by Vikas Mittal and published by CRC Press. This book was released on 2013-10-18 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advancements in polymer nanocomposite foams have led to their application in a variety of fields, such as automotive, packaging, and insulation. Employing nanocomposites in foam formation enhances their property profiles, enabling a broader range of uses, from conventional to advanced applications. Since many factors affect the generation of nanost

Download or read book Integral Structural Polymer Foams written by Fyodor A. Shutov and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integral, or structural, foams are one of the most remarkable materials that have been developed over the last fifteen years. As with all rapidly growing fields, the terminology seems to have grown even faster. Thus there are two names for the material structure itself. In the United States and in Japan the term for these plastics is Structural Foams, whereas in Europe and the USSR the term used is usually Integral Foams. We have adhered to the European term in the text and hope our colleagues will bear with us. Integral foams have a specific structure: a cellular core that gradually turns into a solid skin. The skin gives the part its form and stiffness, while the cellular core contributes to the very high strength-to-weight values of the material. These are higher than those of some unfoamed plastics and metals. The sandwich-like structure with its unique mechanical properties was prompted by nature. Wood and bone are strong and light-weight natural materials having a cellular structure. Since the sandwich-like structure of the integral foams resembles that of natural wood, the foams are often referred to as artifical wood or plastic wood, thereby emphasizing not only the formal structural similarity of these materials, but also one of the main functional applications of integral foams - replacement of wooden articles in various fields of engineering and construction.

Download or read book Blowing Agents and Foaming Processes 2002 written by and published by iSmithers Rapra Publishing. This book was released on 2002 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Foaming with Supercritical Fluids written by Ernesto Di Maio and published by Elsevier. This book was released on 2021-11-06 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foaming with Supercritical Fluids, Volume Nine provides a comprehensive description of the use of supercritical fluids as blowing agents in polymer foaming. To this aim, the fundamental issues on which the proper design and control of this process are rooted are discussed in detail, with specific attention devoted to the theoretical and experimental aspects of sorption thermodynamics of a blowing agent within a polymer, the effect of the absorbed blowing agent on the thermal, interfacial and rheological properties of the expanding matter, and the phase separation of the gaseous phase, and of the related bubble nucleation and growth phenomena. Several foaming technologies based on the use of supercritical blowing agents are then described, addressing the main issues in the light of the underlying chemical-physical phenomena. Offers strong fundamentals on polymer properties important on foaming Outlines the use of supercritical fluids for foaming Covers theoretical points-of-view, including foam formation of the polymer/gas solution to the setting of the final foam Discusses the several processing technologies and applications

Download or read book Applied Plastics Engineering Handbook written by Myer Kutz and published by Elsevier. This book was released on 2023-11-24 with total page 912 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applied Plastics Engineering Handbook: Processing, Sustainability, Materials, and Applications, Third Edition presents the fundamentals of plastics engineering, helping bring readers up-to-speed on new plastics, materials, processing and technology. This revised and expanded edition includes the latest developments in plastics, including areas such as biodegradable and biobased plastics, plastic waste, smart polymers, and 3D printing. Sections cover traditional plastics, elastomeric materials, bio-based materials, additives, colorants, fillers and plastics processing, including various key technologies, plastic recycling and waste. The final part of the book examines design and applications, with substantial updates made to reflect advancements in technology, regulations, and commercialization. Throughout the handbook, the focus is on engineering aspects of producing and using plastics. Properties of plastics are explained, along with techniques for testing, measuring, enhancing, and analyzing them. Practical introductions to both core topics and new developments make this work equally valuable for newly qualified plastics engineers seeking the practical rules-of-thumb they don't teach you in school and experienced practitioners evaluating new technologies or getting up-to-speed in a new field. Offers an ideal reference for new engineers, experienced practitioners and researchers entering a new field or evaluating a new technology Provides an authoritative source of practical advice, presenting guidance that will lead to cost savings and process improvements Includes the latest technology, covering 3D printing, smart polymers and thorough coverage of biobased and biodegradable plastics

Download or read book Investigation of Foaming Behaviors in Injection Molding Using Mold Pressure Profile written by John Won S. Lee and published by . This book was released on 2009 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is intended to improve the understanding of foaming behaviors in various foam injection molding processes: structural foam molding, gas counter pressure molding, and gas counter pressure with mold opening. The foaming behavior in foam injection molding is different from foam extrusion in two ways. First, foaming occurs in a confined volume, which consists of a mold, whereas, it occurs in an open environment in foam extrusion. And second, while the foaming behavior in foam extrusion does not change with time once the steady state is reached, foam injection molding is on the other hand, time-dependent. These differences made it very challenging to study the foaming behaviors in foam injection molding. In this thesis, experiments were first conducted in foam extrusion to understand the effects of processing and material parameters on cell nucleation and growth behaviors. Subsequently, the knowledge obtained from the foam extrusion experiments was transferred to the foam injection molding process and the fundamental foaming mechanisms in foam injection molding were developed by conducting extensive experiments. Four processing parameters were mainly studied in this thesis: injection speed, void fraction setting (i.e., shot size), nitrogen content, and gate resistance. The experimental results revealed that the mold pressure profile during the foam injection molding process governed its foaming behaviors. Furthermore, by analyzing the mold pressure profile during the structural foam molding, it was possible to predict the achievable cell density in structural foam molding based on the foam extrusion results. When the gas counter pressure was employed, the analysis of the foaming behavior was relatively easier since the cell nucleation did not occur during the injection stage. However, the cell density that was achieved by using the gas counter pressure was generally lower than that obtained in structural foam molding due to the lower pressure drop rate caused by the use of the gas counter pressure. It was also discovered that the use of mold opening in combination with the gas counter pressure was very effective when uniform cell structure with a high void fraction was desired in addition to class-A surface quality.