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Polymer and Organic Materials

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Full-Text Articles in Materials Science and Engineering

Validation Of A Secondary Fabric Supplier And Characterization Of Alternate Cores For Use In The Aptera 2e Sandwich Core Composite, Bryan Rogers Jun 2010

Validation Of A Secondary Fabric Supplier And Characterization Of Alternate Cores For Use In The Aptera 2e Sandwich Core Composite, Bryan Rogers

Materials Engineering

Polymer matrix composites’ high strength to weight ratio has made them an ideal material choice for use in lightweight transportation vehicles. Aptera Motors, a company based out of Oceanside, CA, is currently developing a next-generation high efficiency passenger vehicle called the Aptera 2e. The 2e’s body is composed of a sandwich core composite containing laminates of E-glass fibers embedded within an epoxy matrix sandwiched between a polyester hexagonal core. This project looked to validate a secondary fabric supplier for use in Aptera’s composite and characterize the core shear properties of two alternate core materials for future iterations of Aptera’s vehicle. …


Optimization Of P3ht-Pcbm Polymer Solar Cells Through Device Simulation And Manufacturing, James Boom Jun 2010

Optimization Of P3ht-Pcbm Polymer Solar Cells Through Device Simulation And Manufacturing, James Boom

Computer Engineering

Given a good model and implementation of that model, computer simulation can be used to reduce the time and material costs of research. To this end I worked with other students to manufacture, test and simulate the single layer P3HT-PCBM solar cell. Using the data collected from this project, future work can then be done with the project's simulator to further optimize these types of solar cell devices.


Polyenvi, Stephen Beard, Josh Engel, Paul Fake, Diego Flores, Alvaro Nunez, Miguel Wong Jun 2010

Polyenvi, Stephen Beard, Josh Engel, Paul Fake, Diego Flores, Alvaro Nunez, Miguel Wong

Electrical Engineering

Poor indoor air quality is a problem that is recognized by the Environmental Protection Agency (EPA) to cause health issues. In order to raise awareness of this problem, this document outlines the construction of a device that economically measures air quality through five metrics: dust, smoke, ozone, humidity, and temperature. The device integrates with a router to provide users access to information about their indoor air quality anywhere over the internet as well as local access to the data via an LCD mounted on the router. By increasing indoor air quality awareness, this device will aid users in making adjustments …


Determining The Optimal Material For Coffee Packaging: Oxygen Transmission Rates And Ink Abrasion Resistance, Laura Kiyoi Jun 2010

Determining The Optimal Material For Coffee Packaging: Oxygen Transmission Rates And Ink Abrasion Resistance, Laura Kiyoi

Graphic Communication

No abstract provided.


Crosslinked Conventional Size And Nanoparticle Size Acrylic Latexes And Their Blends: Investigation Of The Effects Of Crosslinking, Particle Size And Distribution, Glass Transition Temperature And Blending On Film Formation, Properties And Morphology, Ravi Ghanshyambhai Joshi Apr 2010

Crosslinked Conventional Size And Nanoparticle Size Acrylic Latexes And Their Blends: Investigation Of The Effects Of Crosslinking, Particle Size And Distribution, Glass Transition Temperature And Blending On Film Formation, Properties And Morphology, Ravi Ghanshyambhai Joshi

Master's Theses and Doctoral Dissertations

Synthetic latexes have many product applications including functioning as a binder in paints and coatings. For many years, researchers in industry as well as in academe have been exploring various strategies to improve performance of acrylic latexes mainly to replace traditionally used solvent borne coatings due to increasing environmental concerns and strict governmental regulations. The main goal of the study is to investigate the effects of type (pre-coalescence or post-coalescence) and level of crosslinking, particle size (nano particle size ~ 20-25 nm vs. conventional particle size ~ 120-130 nm) and distribution, glass transition temperature (Tg), and blending on latex film …


Preparation Of Styrene Acrylic Copolymer Toner Resin By Solution Polymerization., Neo Su Siang Apr 2010

Preparation Of Styrene Acrylic Copolymer Toner Resin By Solution Polymerization., Neo Su Siang

Student Works (2010-2019)

This project has investigated solution polymerization to produce toner resins. There are three stages: (i) synthesis of low molecular weight styrene acrylic copolymer; (ii) synthesis of high molecular weight styrene acrylic copolymer; (iii) mixing high and low molecular weight copolymers. Gel Permeation Chromatography (GPC) was used to study molecular weight distributions, Melt Flow Index (MFI) Instrument to study the flowability of resin, Differential Scanning Calorimetry (DSC) to study the thermal properties of resin, and acid number to quantitate the amount of acidic group in the resin. A comparison of properties between the experimental samples, patent’s claims, and commercial resins had …


Gerber Project For Lockheed Martin, Andrew Callahan, Sean Lawyer Mar 2010

Gerber Project For Lockheed Martin, Andrew Callahan, Sean Lawyer

Industrial Technology and Packaging

Lockheed Martin, the world’s premier aerial combat vehicle manufacturer was pressed to find an eco-friendly way to package their impregnated epoxy. In the current system, the epoxy would be cut on the Gerber table to a pre-determined length and then sandwiched inside of two corrugated fiberboard sheets for storage inside of a freezer. The current process was not only labor intensive, but the corrugated fiberboard had to be disregarded after one use. In conjunction with the Cal Poly San Luis Obispo Packaging program and Melmat Incorporated, we were able to find a corrugated plastic substrate to replace the currently non-reusable …


Electrostatic Quadrupole Plasma Mass Spectrometer Measurements During Thin Film Depositions Using Simultaneous Matrix Assisted Pulsed Laser Evaporation And Magnetron Sputtering, Chad N. Hunter, Michael H. Check, Christopher Muratore, Andrey A. Voevodin Jan 2010

Electrostatic Quadrupole Plasma Mass Spectrometer Measurements During Thin Film Depositions Using Simultaneous Matrix Assisted Pulsed Laser Evaporation And Magnetron Sputtering, Chad N. Hunter, Michael H. Check, Christopher Muratore, Andrey A. Voevodin

Chemical and Materials Engineering Faculty Publications

A hybrid plasma deposition process, combining matrix assisted pulsed laser evaporation (MAPLE) of carbon nanopearls (CNPs) with magnetron sputtering of gold was investigated for growth of composite films, where 100 nm sized CNPs were encapsulated into a gold matrix. Composition and morphology of such composite films was characterized with x-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy (TEM) analysis. Carbondeposits on a gold magnetron sputter target and carbon impurities in the gold matrices of depositedfilms were observed while codepositing from gold and frozen toluene-CNP MAPLE targets in pure argon. Electrostatic quadrupole plasma analysis was used to determine that …


Characteristics Of Proton Conducting Pva-Chitosan Polymer Blend Electrolytes., Mohd Fakhrul Zamani Abdul Kadir Jan 2010

Characteristics Of Proton Conducting Pva-Chitosan Polymer Blend Electrolytes., Mohd Fakhrul Zamani Abdul Kadir

Student Works (2010-2019)

The main focus of this present work is to build a good conducting solid polymer electrolyte (SPE) based on chitosan and poly(vinyl alcohol)(PVA) blend. Solution cast technique has been employed to produce sample films in this work. From the scanning electron micrographs (SEM) the surface morphology of the blend containing 40 wt.% chitosan and 60 wt.% PVA (C4P6) is homogenous and miscible in one and another. The C4P6 film is the most amorphous and is the best candidate for the polymer host in the electrolyte systems studied in the present work. Ammonium Nitrate (NH4NO3) is the doping salt that provides …


Thermo-Electrical And Mechanical Studies On Polymer-Organically Modified Montmorillonite Composite., Norhana Abdul Halim Jan 2010

Thermo-Electrical And Mechanical Studies On Polymer-Organically Modified Montmorillonite Composite., Norhana Abdul Halim

Student Works (2010-2019)

The field of polymer-nanoclay composite has attracted a lot of attention in materials studies due to the dramatic improvement on polymers characteristics. For example mechanical and thermal properties, chemical resistance as well as the reduced gas permeability. However, structural changes and the mechanisms that may contribute to these improvements are not fully understood. In this work, the study on polymer nanoclay composite concentrates on the effects of OMON inclusion within different polymer matrix systems. The matrixes are a series of natural rubbers (Standard Malaysia Rubber – Latex grade (SMRL); Deproteinized Natural Rubber (DPNR) and Epoxidized Natural Rubber (ENR-50)), plasticized Polyvinyl …


Electrical And Structural Studies Of Polyacrylonitrile (Pan) Complexed With Inorganic Salts., Khairul Bahiyah Md Isa Jan 2010

Electrical And Structural Studies Of Polyacrylonitrile (Pan) Complexed With Inorganic Salts., Khairul Bahiyah Md Isa

Student Works (2010-2019)

In the present study, polymer electrolyte films composed of polyacrylonitrile (PAN) as a host polymer, ethylene carbonate (EC) as the plasticizer and lithium triflate (LiCF3SO3) and sodium triflate (NaCF3SO3) as dopant salts were prepared by the solution cast technique. Five systems of polymer electrolytes films have been prepared; these systems are the plasticized-PAN system i.e. PAN-EC system, two salted-PAN systems i.e. PAN-LiCF3SO3 and PAN-NaCF3SO3, and two plasticized-salted PAN systems i.e. PAN-EC-LiCF3SO3 and PAN-EC-NaCF3SO3. The pure PAN film was prepared as a reference. The ionic conductivity for each system is characterized using impedance spectroscopy. The room temperature conductivity of the pure …


Self-Organized Nanolayers Of Organosilane Molecules, Ocelio V. Lima Dec 2009

Self-Organized Nanolayers Of Organosilane Molecules, Ocelio V. Lima

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

There is a high degree of interest in organic thin films for lightweight, low power, rugged and flexible electronics. Conjugated organic molecules with polycyclic rings are being considered a major enabler of such applications. Due to a surface tension mismatch between the organic molecule with the inorganic support (mainly silicon oxides), molecular packing inside these thin films is often disordered, which suppresses the device performance. There are major efforts focused on modifying the bulk properties, for instance, maximizing orbital overlaps in the solid state, little attention was paid to receive long-range ordered thin films. A novel approach to afford conjugated …


Modeling Of Metal-Ferroelectric-Insulator-Semiconductor Structures Based On Langmuir–Blodgett Copolymer Films, Timothy J. Reece, Stephen Ducharme Dec 2009

Modeling Of Metal-Ferroelectric-Insulator-Semiconductor Structures Based On Langmuir–Blodgett Copolymer Films, Timothy J. Reece, Stephen Ducharme

Stephen Ducharme Publications

Among the ferroelectric thin films used in field-effect transistor devices; the ferroelectric copolymer of polyvinylidene fluoride PVDF –CH2–CF2–, with trifluoroethylene TrFE –CHF–CF2–, has distinct advantages, including low dielectric constant, low processing temperature, low cost, and compatibility with organic semiconductors. The operation of a metal-ferroelectric insulatorsemiconductor structure with PVDF-TrFE as the ferroelectric layer was analyzed and optimized by numerical solution of the Miller and McWhorter model. A model device consisting of 20 nm PVDF/TrFE on a 10-nm-thick high-k dielectric buffer exhibits a memory window of 5 V with an operating voltage of 15 V. The operating voltage can be reduced to …


Feasibility Of Ellipsometric Sensor Development For Use During Pecvd Siox Coated Polymer Product Manufacturing, Daniel Lynn Helms Sep 2009

Feasibility Of Ellipsometric Sensor Development For Use During Pecvd Siox Coated Polymer Product Manufacturing, Daniel Lynn Helms

Master's Theses

Polymeric materials have provided pathways to products that could not be manufactured otherwise. A new technology which merges the benefits of ceramics into these polymer products has created materials ideally suited to many different industries, like food packaging. Nano Scale Surface Systems, Inc. (NS3), a company which coats polymers with ceramic oxides like SiO2 through a process known as plasma enhanced chemical vapor deposition (PECVD), was interested in the feasibility of an in line measurement system for monitoring the deposited films on various polymer products. This project examined two different coated polymer products, polyethylene terephthalate (PET) beverage containers and biaxially …


Assessment Of Electrospinning As An In-House Fabrication Technique For Blood Vessel Mimic Cellular Scaffolding, Colby M. James Sep 2009

Assessment Of Electrospinning As An In-House Fabrication Technique For Blood Vessel Mimic Cellular Scaffolding, Colby M. James

Master's Theses

Intravascular devices, such as stents, must be rigorously tested before they can be approved by the FDA. This includes bench top in vitro testing to determine biocompatibility, and animal model testing to ensure safety and efficacy. As an intermediate step, a blood vessel mimic (BVM) testing method has been developed that mimics the three dimensional structure of blood vessels using a perfusion bioreactor system, human derived endothelial cells, and a biocompatible polymer scaffold used to support growth of the blood vessel cells. The focus of this thesis was to find an in-house fabrication method capable of making cellular scaffolding for …


Dielectric Nanocomposites: An Inside-Out Approach To Storing Electrostatic Energy, Stephen Ducharme Sep 2009

Dielectric Nanocomposites: An Inside-Out Approach To Storing Electrostatic Energy, Stephen Ducharme

Stephen Ducharme Publications

The ability to achieve high-energy densities is the central challenge in energy storage and recovery. A promising strategy for increasing energy storage is to use highperformance dielectric materials, such as highly polarizable nanoparticles or polymers, or nanocomposites of the two. In this issue, Kim et al. use a molecular coating and clever chemistry to combine oxide nanoparticles with a polymer matrix, thereby producing an improved nanocomposite dielectric. Some advantages and challenges of using nanocomposites as improved dielectric materials are presented in this Perspective.


Chameleon Coatings: Adaptive Surfaces To Reduce Friction And Wear In Extreme Environments, Christopher Muratore, Andrey A. Voevodin Aug 2009

Chameleon Coatings: Adaptive Surfaces To Reduce Friction And Wear In Extreme Environments, Christopher Muratore, Andrey A. Voevodin

Chemical and Materials Engineering Faculty Publications

Adaptive nanocomposite coating materials that automatically and reversibly adjust their surface composition and morphology via multiple mechanisms are a promising development for the reduction of friction and wear over broad ranges of ambient conditions encountered in aerospace applications, such as cycling of temperature and atmospheric composition. Materials selection for these composites is based on extensive study of interactions occurring between solid lubricants and their surroundings, especially with novel in situ surface characterization techniques used to identify adaptive behavior on size scales ranging from 10−10 to 10−4 m. Recent insights on operative solid-lubricant mechanisms and their dependency upon the ambient environment …


Design And Development Of Rapid Battery Exchange Systems For Electric Vehicles To Be Used As Efficient Student Transportation, Jonathan A. Bevier Jul 2009

Design And Development Of Rapid Battery Exchange Systems For Electric Vehicles To Be Used As Efficient Student Transportation, Jonathan A. Bevier

Master's Theses

Rapid battery exchange systems were built for an electric van and pedal assist electric bike as a method of eliminating the need to recharge the vehicles batteries in order to increase the feasibility of using electric propulsion as a method of efficient student transportation. After selecting proper materials it was found that the systems would need a protective coating to ensure consistent operation. 1020 cold rolled steel samples coated with multiple thicknesses of vinyl resin paint, epoxy resin paint, and powder coating were subjected to environmental wear tests in order to determine if the type and thickness of common protective …


Polarization Switching Kinetics Of Ferroelectric Nanomesas Of Vinylidene Fluoride-Trifluoroethylene Copolymer, R. V. Gaynutdinov, O. A. Lysova, S. G. Yudin, A. L. Tolstikhina, A. L. Kholkin, V. M. Fridkin, Stephen Ducharme Jul 2009

Polarization Switching Kinetics Of Ferroelectric Nanomesas Of Vinylidene Fluoride-Trifluoroethylene Copolymer, R. V. Gaynutdinov, O. A. Lysova, S. G. Yudin, A. L. Tolstikhina, A. L. Kholkin, V. M. Fridkin, Stephen Ducharme

Stephen Ducharme Publications

The polarization switching kinetics of ferroelectric polymer nanomesas was investigated using piezoresponse force microscopy. The nanomesas were made by self-organization from Langmuir–Blodgett films of a 70% vinylidene fluoride and 30% trifluoroethylene copolymer. The polarization switching time exhibits an exponential dependence on reciprocal voltage that is consistent with nucleation-type switching dynamics.


Evaluating The Electrical Response Of Polyaniline To Mechanical Strain, Matthew L. Goebel Jun 2009

Evaluating The Electrical Response Of Polyaniline To Mechanical Strain, Matthew L. Goebel

Master's Theses

This thesis focuses on the electrical output of polyaniline films subjected to uniaxial strain in hydrochloric acid solutions. Polyaniline belongs to novel class of materials known as conducting polymers. Alternating single and double bonds in the backbone of conducting polymers allow them to transmit electric charge when they are doped with negatively charged ions. Modifying the degree of doping and other electrical/chemical treatments allow conducting polymers to exhibit conducting, semi-conducting, or insulating electrical properties. Resilient mechanical properties, good processability, and low cost make conducting polymers good candidates for applications traditionally held by metals and semi-conductors.

When tensile strain is applied …


Interfacial Energy Between Carbon Nanotubes And Polymers Measured From Nanoscale Peel Tests In The Atomic Force Microscope, Mark C. Strus, Camilo I. Cano, R. Byron Pipes, Cattien V. Nguyen, Arvind Raman Mar 2009

Interfacial Energy Between Carbon Nanotubes And Polymers Measured From Nanoscale Peel Tests In The Atomic Force Microscope, Mark C. Strus, Camilo I. Cano, R. Byron Pipes, Cattien V. Nguyen, Arvind Raman

Other Nanotechnology Publications

The future development of polymer composite materials with nanotubes or nanoscale fibers requires the ability to understand and improve the interfacial bonding at the nanotube-polymer matrix interface. In recent work [Strus MC, Zalamea L, Raman A, Pipes RB, Nguyen CV, Stach EA. Peeling force spectroscopy: exposing the adhesive nanomechanics of one-dimensional nanostructures. Nano Lett 2008;8(2):544–50], it has been shown that a new mode in the Atomic Force Microscope (AFM), peeling force spectroscopy, can be used to understand the adhesive mechanics of carbon nanotubes peeled from a surface. In the present work, we demonstrate how AFM peeling force spectroscopy can be …


Potential Migration Of Ε-Caprolactam To Water And Wine As Affected By Transportation And Storage, Joseph C. Ianneo Mar 2009

Potential Migration Of Ε-Caprolactam To Water And Wine As Affected By Transportation And Storage, Joseph C. Ianneo

Master's Theses

Abstract: Under normal sealing and storage conditions, Nylon-6, poly-caprolactam-based plastic laminates may release impurities to packaged foods and liquids and the application of heat for cooking often increases the rate of migration. Epsilon-caprolactam is one of the main contaminates found to migrate from a Nylon-6 poly-caprolactam plastic film. The objectives of this study were to determine the effects of solvent, transportation and storage time on the migration of ε-caprolactam from a Nylon-6-based lidding material into water or a white wine substitute (12% ethanol). Polypropylene plastic cups were filled, sealed, packaged, stacked and exposed to a simulated 3-day cross-country shipment. Cups …


Materials And Coatings Derived From The Polymerizable Ionic Liquid Surfactants 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium Tetrafluoroborate And 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium 2-Acrylamido-2-Methyl-Propylsulfonate, Hong Gu Mar 2009

Materials And Coatings Derived From The Polymerizable Ionic Liquid Surfactants 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium Tetrafluoroborate And 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium 2-Acrylamido-2-Methyl-Propylsulfonate, Hong Gu

Master's Theses and Doctoral Dissertations

Polymerizable ionic liquid surfactants were synthesized and polymerized, yielding engineered advanced polymers that can be tailored for diverse applications. First, 1-(2-acryloyloxyundecyl)-3-methylimidazolium tetrafluoroborate (IL-BF4) was synthesized and was copolymerized with methyl methacrylate (MMA) via microemulsion polymerization. The resulting polymer gels can be transformed into porous materials by anion exchange, and the porosity of the material can be tuned through the solvent shifting. Second, an ionic liquid composed of a 1-(2-acryloyloxyundecyl)-3- methylimidazolium (IL) cation and 2-acryloamido-2-methyl-propylsulfonate (AMPS) anion was synthesized and polymerized by UV irradiation, and introductory data are illustrated for humidity sensitive preparations suitable for chemFETs, for proton conducting …


A Systematic Study On Structural And Optical Properties In Conjugated Polymer Photovoltaic Devices, Sri Sabarinadh Sunkavalli Oct 2008

A Systematic Study On Structural And Optical Properties In Conjugated Polymer Photovoltaic Devices, Sri Sabarinadh Sunkavalli

Electrical & Computer Engineering Theses & Dissertations

Conjugated polymer/fullerene based solar cells represent an exciting alternative to inorganic ones because of their low production costs, flexibility and low weight. At present, commercialization of organic photovoltaic (OPV) cells is limited due to their relatively low efficiency in comparison to silicon ones. In order to understand the operation of OPV cells and to increase their efficiency, more information about the structure of the absorber layer is needed. In particular, the connection between structure and properties of the absorber layer is of great importance. Performance of bulk heterojunction organic solar cells based on poly (3-hexylthiophene) as donor and a soluble …


Big Challenges In Designing Small Parts For Mass Production, Kevin Delaney, David Kennedy Sep 2008

Big Challenges In Designing Small Parts For Mass Production, Kevin Delaney, David Kennedy

Conference Papers

Micro manufacturing involves the production of parts or products with features on a micro scale. The technology is used to produce parts for several business sectors which have experienced dramatic growth in recent years and forecasts are that this growth will continue in the years ahead. With the loss of traditional manufacturing jobs to lower-cost locations many companies in Ireland see micro manufacturing as having significant potential to preserve and increase revenue. A move into micro manufacturing will present significant opportunities for those companies willing to take the risk of producing parts with micro dimensions. Such a transition is a …


Equi-Biaxial Fatigue Of Elastomers: The Effect Of Oil Swelling On Fatigue Life, Stephen Jerrams, John Hanley, Niall Murphy, Ali Hassan Sep 2008

Equi-Biaxial Fatigue Of Elastomers: The Effect Of Oil Swelling On Fatigue Life, Stephen Jerrams, John Hanley, Niall Murphy, Ali Hassan

Articles

The effect of oil swelling on the fatigue life of ethylene propylene diene monomer rubber (EPDM) has been studied under conditions of equi-biaxial cycling using dynamic bubble inflation. Specimens were subjected to varying degrees of swelling in reference mineral oils and fatigued at constant engineering stress amplitudes. The reference oils used for swelling the EPDM had known aniline points, allowing the rubber-oil compatibility to be determined. The inflation fluid for fatigue testing was selected with a solubility parameter that would produce a desired level of incompatibility with the test specimens, thereby limiting the amount of additional swelling during cycling. Wöhler …


Raman Studies Of 1,3,5,7 Cyclooctatetraene At High Pressure, Martin Galley, Ed Romano, Sergey Tkachev, Michael Pravica Aug 2008

Raman Studies Of 1,3,5,7 Cyclooctatetraene At High Pressure, Martin Galley, Ed Romano, Sergey Tkachev, Michael Pravica

Undergraduate Research Opportunities Program (UROP)

We performed Raman spectroscopic studies of 1,3,5,7-cyclooctatetraene at elevated pressures up to 10 GPa with the aim of examining possible planarization of the molecule and further studying two prior-discovered phases of the solid with pressure. The Raman excitation source was a Krypton-ion laser operating at 674.1 nm (give wavelength).

1,3,5,7 Cyclooctatetraene has an octagonal formation however it is not aromatic or anti-aromatic (not a subject to the 4n+2 Huckel’s rule) [1]. As a result, its adopts a somewhat reactive tub shape. Upon the addition or removal of one to two electrons under ambient conditions, the molecule planarizes and becomes aromatic …


The Effects Of Build Orientation, Diameter And Printhead Life On The Cylindricity Of Three-Dimensionally Printed Parts, Troy E. Ollison May 2008

The Effects Of Build Orientation, Diameter And Printhead Life On The Cylindricity Of Three-Dimensionally Printed Parts, Troy E. Ollison

All-Inclusive List of Electronic Theses and Dissertations

Rapid prototyping (RP) technologies have become more than just a fast and inexpensive way to produce prototypes. Today RP is widely used to produce functional prototypes, end-use parts and tooling as well as visual prototypes. When RP is used for end-use parts with interconnected moving assemblies or for producing metal casting molds which must have sufficient material for machining tolerances, accuracy is very critical. However, in general, accuracy of the finished RP parts is relatively low lll compared to parts produced by traditional manufacturing processes. The understanding of why some of these accuracy differences exist is either unknown or not …


Effect Of Carbon Black On The Mechanical Performances Of Magnetorheological Elastomers, Lin Chen Jan 2008

Effect Of Carbon Black On The Mechanical Performances Of Magnetorheological Elastomers, Lin Chen

Articles

Several magnetorheological elastomer (MRE) samples, with different weight percentages of carbon black, were fabricated under a constant magnetic field. Their microstructures were observed by using an environmental scanning electron microscope (SEM), and their mechanical performance including magnetorheological (MR) effect, damping ratio and tensile strength were measured with a dynamic mechanical analyzer (DMA) system and an electronic tensile machine. The experimental results demonstrate that carbon black plays a significant role in improving the mechanical performance of MR elastomers. Besides the merits of high MR effect and good tensile strength, the damping ratio of such materials is much reduced. This is expected …


Damping Of Magnetorheological Elastomers, Lin Chen Jan 2008

Damping Of Magnetorheological Elastomers, Lin Chen

Articles

The damping property of magnetorheological (MR) elastomers is characterized by a modified dynamic mechanical-magnetic coupled analyzer. The influences of the external magnetic flux density, damping of the matrix, content of iron particles, dynamic strain and driving frequency on the damping properties of MR elastomers were investigated experimentally. The experimental results indicate that the damping properties of MR elastomers greatly depend on the interfacial slipping between the inner particles and the matrix. Different from general composite materials, the interfacial slipping in MR elastomers is affected by the external applied magnetic field.