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Articles 541 - 570 of 657
Full-Text Articles in Mechanical Engineering
Nonlinear Dynamics Of Electrostatically Actuated M/Nems Plates To Include Casimir And Van Der Waals Effects, Reynaldo Oyervides
Nonlinear Dynamics Of Electrostatically Actuated M/Nems Plates To Include Casimir And Van Der Waals Effects, Reynaldo Oyervides
Theses and Dissertations - UTB/UTPA
The amplitude-frequency response and voltage-amplitude response of electrostatically actuated micro and nano-electromechanical systems (M/NEMS) clamped circular plates are investigated. The system is actuated by soft AC voltage at frequency near half natural frequency of the plate, and another case near natural frequency of the plate, they resulting in primary and parametric resonances of the system, respectively. The system is first analytically modeled using the Method of Multiple Scales (MMS). MMS results are then compared to Reduced Order Model (ROM) method frequency response numerical simulations. Besides MMS and ROM, time response simulations are conducted. The agreement of the frequency responses of …
Natural Polymer Based Composite Scaffolds For Tissue Engineering Applications, Marcos R. Villarreal
Natural Polymer Based Composite Scaffolds For Tissue Engineering Applications, Marcos R. Villarreal
Theses and Dissertations - UTB/UTPA
The fabrication, characterization, and bio-assessment of two types of perspective tissue engineering (TE) scaffolds are presented. Principally derived of biopolymers, both types of scaffolds generally followed porous scaffold methodologies for synthesis. Differentiating the two scaffold varieties was chiefly driven by crosslinking attainment, where crosslinking is argued to add structural stability and aid in regulating biodegradability rates in TE scaffolds. Microwave irradiation via conventional microwave was one method used to prospectively crosslink cornstarch to chitosan and sodium alginate. Triethyl orthoformate, was used to prospectively crosslink collagen and chitosan. After the scaffolds were “crosslinked” they were subjected to freeze drying techniques in …
Investigation Of Slective Laser Melting Of Mecanically Alloyed Metastable Al5fe2 Powder, Hugo Montiel
Investigation Of Slective Laser Melting Of Mecanically Alloyed Metastable Al5fe2 Powder, Hugo Montiel
Theses and Dissertations - UTB/UTPA
Selective Laser Melting (SLM), an Additive Manufacturing (AM) technology, enables the production of complex structured metal products. Aluminum alloys are used in SLM as high-strength lightweight materials for weight reduction in structural components. Previous investigations report high laser powers (300 W) and slow scanning speeds (500 mm/s) to process aluminum alloys under SLM. This research investigates the SLM processing of Al-Fe alloy by utilizing metastable Al5Fe2 powder system produced by mechanical alloying. Metastable systems are thermodynamically activated with internal energy that can generate an energy shortcut when processing under SLM. The optimum laser power, scan speeds and scan distances were …
Computational Prediction Of Remodeling Of Collagen Fiber Network In Articular Cartilage Under Dynamic Unconfined Compression, Juan Andres Coello Amado
Computational Prediction Of Remodeling Of Collagen Fiber Network In Articular Cartilage Under Dynamic Unconfined Compression, Juan Andres Coello Amado
Theses and Dissertations - UTB/UTPA
A poroelastic finite element model of a heterogeneous cartilage disk was created based on previous studies and experimental setups; this allows us to study cartilage behavior under dynamic unconfined compression. Previous studies have used a Post Hoc approach, which consist of searching for patterns or relationships between predicted mechanical parameters obtained through computational and experimental results. Our goal in this study is to take the same Post-Hoc approach and identify patterns between predicted mechanical parameters, such as fiber strain or stress, and experimentally-measured collagen fiber distribution (i.e. reorientation of fibers under dynamic unconfined compression). After computational predictions were obtained, it …
A Study Of The Selective Laser Alloying Of Elemental Titanium And Boron Powder, Yingbin Hu
A Study Of The Selective Laser Alloying Of Elemental Titanium And Boron Powder, Yingbin Hu
Theses and Dissertations - UTB/UTPA
To better understand the selective laser alloying process of elemental titanium and boron powder, theoretic models are created which takes material related, reaction related, laser related, and other affecting factors into consideration. These models do help interpret the corresponding experiment results. In turn, the related experiment results validate the theoretic models created. In practice, the experiments with two different molar ratios of 1:2 and 4:1 between titanium and boron are carried out. The huge amount of energy released because of reaction between titanium and boron during laser irradiation makes it hard to understand and control the alloying process. At the …
Tracking Of Spall Deterioration On Tapered Roller Bearings, Amy Gonzalez, Constantine Tarawneh, Ping Hu, Joseph A. Turner, Brent Wilson
Tracking Of Spall Deterioration On Tapered Roller Bearings, Amy Gonzalez, Constantine Tarawneh, Ping Hu, Joseph A. Turner, Brent Wilson
Mechanical Engineering Faculty Publications
Fatigue spall initiation is one of the major modes of premature bearing failure. The spall initiation is often exacerbated by the presence of impurities in the near-surface region (∼400 μm) of the bearing raceways. Once a spall initiates, it can propagate rapidly, leading to abnormal bearing operation and possible catastrophic failure if not detected early. Testing performed at the University of Texas-Pan American (UTPA) has focused on ultrasonically scanned tapered roller bearings found to have inclusion content within 400 μm of the surface of the raceways. These bearings undergo accelerated service life tests in which spall initiation is detected and …
Fatigue Life Estimation Of Modified Railroad Bearing Adapters For Onboard Monitoring Applications, Alexis Trevino, Arturo A. Fuentes, Constantine Tarawneh, Joseph Montalvo
Fatigue Life Estimation Of Modified Railroad Bearing Adapters For Onboard Monitoring Applications, Alexis Trevino, Arturo A. Fuentes, Constantine Tarawneh, Joseph Montalvo
Mechanical Engineering Faculty Publications
This paper presents a study of the fatigue life (i.e. number of stress cycles before failure) of Class K cast iron conventional and modified railroad bearing adapters for onboard monitoring applications under different operational conditions based on experimentally validated Finite Element Analysis (FEA) stress results. Currently, freight railcars rely heavily on wayside hot-box detectors (HBDs) at strategic intervals to record bearing cup temperatures as the train passes at specified velocities. Hence, most temperature measurements are limited to certain physical railroad locations. This limitation gave way for an optimized sensor that could potentially deliver significant insight on continuous bearing temperature conditions. …
Nanofiber-Based Membrane Separators For Lithium-Ion Batteries, Mataz Alcoutlabi, Hun Lee, Xiangwu Zhang
Nanofiber-Based Membrane Separators For Lithium-Ion Batteries, Mataz Alcoutlabi, Hun Lee, Xiangwu Zhang
Mechanical Engineering Faculty Publications
Nanofiber-based membranes were prepared by two different methods for use as separators for Lithium-ion batteries (LIBs). In the first method, Electrospinning was used for the fabrication of Polyvinylidene fluoride PVDF nanofiber coatings on polyolefin microporous membrane separators to improve their electrolyte uptake and electrochemical performance. The nanofiber-coated membrane separators show better electrolyte uptake and ionic conductivity than that for the uncoated membranes. In the second method, Forcespinning® (FS) was used to fabricate fibrous cellulose membranes as separators for LIBs. The cellulose fibrous membranes were made by the Forcespinning® of a cellulose acetate solution precursor followed by a subsequent alkaline hydrolysis …
Proper Orthogonal Decomposition For Incompressible And Compressible Flows, Seyed Milad Rafieinaini
Proper Orthogonal Decomposition For Incompressible And Compressible Flows, Seyed Milad Rafieinaini
Theses and Dissertations - UTB/UTPA
In this project, reduced order modelling technique has been used to investigate incompressible and compressible flows. At first, Proper Orthogonal Decomposition (POD), Singular Value Decomposition (SVD) and Principal Component Analysis (PCA) have been used to analyze pulsed jet flow as an incompressible flow and supersonic impinging jet as a compressible flow. Then, two flows have been investigated from physics point of view and finally the link between physics of flows and modes have been studied. All investigations have been done based on the given data from Particle Image Velocimetry (PIV). These data have been analyzed by using MATLAB®. Finally, the …
Surface Characterization Of 316l Stainless Steel For Biomedical Applications, Lawrence Cano
Surface Characterization Of 316l Stainless Steel For Biomedical Applications, Lawrence Cano
Theses and Dissertations - UTB/UTPA
Stainless steel alloys play an important role in the field of biomaterials due to their exceptional corrosion resistance and biocompatibility. These alloys have the capability to enhance the quality of a human life by altering various structures of human physiology. The close proximity these alloys have with destructive body fluids, ion dissolution is a detrimental cause from the corrosion initiative and may cause unfavorable reactions. A view on developing an improved compatible surface for the human body leads to implementation of different chemical surface modifications used for creating features that must be corrosion resistant and biologically active without changing the …
Aerodynamic Flow Field Characterization Of Airfoils With And Without Leading Edge Modifications, Oscar Hernandez
Aerodynamic Flow Field Characterization Of Airfoils With And Without Leading Edge Modifications, Oscar Hernandez
Theses and Dissertations - UTB/UTPA
Recently, much focus has been on comprehending the aerodynamic properties associated with the humpback whales pectoral fin. The perturbations found on its leading edge are believed to attribute to the humpbacks maneuverability significantly. These tubercles are assumed to be analogous to strakes on an aircraft, which generate large-scale vortices. More specifically, the vortices prompted by the leading edge increase the momentum exchange within the boundary layer, allowing the flow to remain attached at higher angles of attack, thus delaying stall and in turn increase lift by a passive means of reducing drag. The focus of this investigation is on characterizing …
Structural Integrity Of Conventional And Modified Railroad Bearing Adapters For Onboard Monitoring, Joseph Montalvo, Alexis Trevino, Arturo A. Fuentes, Constantine Tarawneh
Structural Integrity Of Conventional And Modified Railroad Bearing Adapters For Onboard Monitoring, Joseph Montalvo, Alexis Trevino, Arturo A. Fuentes, Constantine Tarawneh
Mechanical Engineering Faculty Publications
This paper presents a detailed study of the structural integrity of conventional and modified railroad bearing adapters for onboard monitoring applications. Freight railcars rely heavily on weigh bridges and stations to determine cargo load. As a consequence, most load measurements are limited to certain physical railroad locations. This limitation provided an opportunity for an optimized sensor that could potentially deliver significant insight on bearing condition monitoring as well as load information. Bearing adapter modifications (e.g. cut outs) were necessary to house the sensor and, thus, it is imperative to determine the reliability of the modified railroad bearing adapter, which will …
Direct Numerical Simulation Of Three-Dimensional Gravity Current On A Uniform Slope, A. Ooi, Nadim Zgheib, S. Balachandar
Direct Numerical Simulation Of Three-Dimensional Gravity Current On A Uniform Slope, A. Ooi, Nadim Zgheib, S. Balachandar
Mechanical Engineering Faculty Publications
Gravity currents occur when fluids of different density are brought together. When gravity currents travel down a uniform slope, buoyancy effects become more important and changes the physical dynamics of its motion. In the present paper, we report data from full three-dimensional direct numerical simulation of gravity currents propagating down a uniform slope. Our data shows that in most cases, the gravity current evolve to a shape that is similar to a triangular wedge. The physical mechanisms leading to formation of this triangular shape and the dynamics of such a structure is presented
Low Speed Water Tunnel Testing, John J. Taylor
Low Speed Water Tunnel Testing, John J. Taylor
Theses and Dissertations - UTB/UTPA
Water tunnels are ideal for studying flow patterns for hydrodynamic effects. The functionality of the University of Texas-Pan American water tunnel was limited by not being able to measure forces and moments corresponding to flow patterns. This report delivers an experimental set-up for calibrating the velocity of the water and development of a load measuring system to relate simultaneous visual investigation. An in-depth parts breakdown of the SST-model pump and the dye injection system for flow visualization will be reviewed. Few balances have been made for water tunnels due to small and difficult to measure flow-induced forces. The motive is …
Effects Of Vapor Grown Carbon Nanofibers On Electrical And Mechanical Properties Of A Thermoplastic Elastomer, Daniel Thomas Basaldua
Effects Of Vapor Grown Carbon Nanofibers On Electrical And Mechanical Properties Of A Thermoplastic Elastomer, Daniel Thomas Basaldua
Theses and Dissertations - UTB/UTPA
Carbon nanofiber (CNF) reinforced composites are exceptional materials that exhibit superior properties compared to conventional composites. This paper presents the development of a vapor grown carbon nanofiber (VGCNF) thermoplastic polyurethane (TPU) composite by a melt mixing process. Dispersion and distribution of CNFs inside the TPU matrix were examined through scanning electron microscopy to determine homogeneity. The composite material underwent durometer, thermal gravimetric analysis, differential scanning calorimetry, heat transfer, hysteresis, dynamic modulus, creep, tensile, abrasion, and electrical conductivity testing to characterize its properties and predict behavior. The motivation for this research is to develop an elastomer pad that is an electrically …
A Preventive Maintenance Framework In Dairy Production Operations, Maria F. Vargas
A Preventive Maintenance Framework In Dairy Production Operations, Maria F. Vargas
Theses and Dissertations - UTB/UTPA
Dairy operations suffer frequent stops. Product shrinkage is a consequence of downtime, which includes losses of packaging material, scraped finish product and capacity. This work proposes a troubleshooting methodology to identify causes of downtime, estimation of waste cost, and minimization of operation disruptions by applying a combination of a cost function to assess waste, and performance measurements. The drinkable yogurt process is evaluated to find the principal areas for wasted bottles and yogurt. In order to make a decision about which of those sources to address, a General Cost Function is used to estimate waste cost which include measurements that …
Fabrication And Characterization Of Silver- And Copper-Coated Nylon 6 Forcespun Nanofibers By Thermal Evaporation, Dorina M. Mihut, Karen Lozano, Heinrich D. Foltz
Fabrication And Characterization Of Silver- And Copper-Coated Nylon 6 Forcespun Nanofibers By Thermal Evaporation, Dorina M. Mihut, Karen Lozano, Heinrich D. Foltz
Mechanical Engineering Faculty Publications
Silver and copper nanoparticles were deposited as thin films onto substrates consisting of Nylon 6 nanofibers manufactured using forcespinningR equipment. Different rotational speeds were used to obtain continuous nanofibers of various diameters arranged as nonwoven mats. The Nylon 6 nanofibers were collected as successive layers on frames, and a high-vacuum thermal evaporation method was used to deposit the silver and copper thin films on the nanofibers. The structures were investigated using scanning electron microscopy–scanning transmission electron microscopy, atomic force microscopy, x-ray diffraction, and electrical resistance measurements. The results indicate that evaporated silver and copper nanoparticles were successfully deposited on Nylon …
Long-Lasting Effect Of Initial Configuration In Gravitational Spreading Of Material Fronts, Nadim Zgheib, Thomas Bonometti, S. Balachandar
Long-Lasting Effect Of Initial Configuration In Gravitational Spreading Of Material Fronts, Nadim Zgheib, Thomas Bonometti, S. Balachandar
Mechanical Engineering Faculty Publications
We present the results from laboratory experiments and fully resolved simulations pertaining to finite-release turbulent density flows with a non-axisymmetric initial shape. First, we demonstrate that the effects of the initial shape influence the current’s evolution well into the long-time phase which would corresponds to the inertial self-similar phase in the case of planar or axisymmetric configurations. Then, we identify the physical mechanisms responsible for this dependence and propose a new model capable of capturing the dynamics of such releases. Finally, we show that this dependence on the initial configuration is robust for various types of gravity currents over a …
A Decision Support Model For Process Planning In Remanufacturing Using Fuzzy Set Theory And Genetic Algorithm, Juan C. Martinez
A Decision Support Model For Process Planning In Remanufacturing Using Fuzzy Set Theory And Genetic Algorithm, Juan C. Martinez
Theses and Dissertations - UTB/UTPA
The environmental awareness and resources preservation has boosted the use of remanufacturing processes. Many important studies have been made in this area, but there are still pitfalls and opportunities that have not been explored yet. Specifically, the cleaning processes play a critical role in remanufacturing. It is among the top of most costly processes and it plays a key step in remanufacturing because delivers a free of contaminant product ready for reprocessing. Understanding and selecting the best processes to meet the need and goals of remanufacturers are important for effective and efficient remanufacturing. Due to variables and high uncertainty associated …
A Study Comparing The Pedagogical Effectiveness Of Virtual Worlds And Of Traditional Training Methods, Benjamin Peters
A Study Comparing The Pedagogical Effectiveness Of Virtual Worlds And Of Traditional Training Methods, Benjamin Peters
Theses and Dissertations - UTB/UTPA
This experiment tests whether a virtual world is a more suitable alternative to classical paper and pen case studies for teaching people how to disarm improvised explosive devices (IED). Following preliminary training, the subjects are separated into a group of 32 and one of 33. The odd-numbered subjects receive case studies while the even-numbered subjects receive training in the virtual world, Second Life. After their training, each subject is put into a simulated test where they attempt to properly disarm a mock IED attached to a victim played by an actor/actress. The results of the experiment show no significant difference …
Creating A Seamless Pipeline Into Undergraduate Programs In Stem Fields Through Region-Wide Articulation Agreements, Immanuel Edinbarough, Mikhail M. Bouniaev, Bill W. Elliott
Creating A Seamless Pipeline Into Undergraduate Programs In Stem Fields Through Region-Wide Articulation Agreements, Immanuel Edinbarough, Mikhail M. Bouniaev, Bill W. Elliott
Manufacturing & Industrial Engineering Faculty Publications
Underrepresented minority students pursue science, technology, engineering, and mathematics (STEM) related degrees at much lower rates compared to other segments of the population. To attract minority students, schools with STEM programs have resorted to myriad strategies such as cohorts, scholarships, mentoring, summer bridges, etc. Some schools have also sought innovative ways to develop a pipeline for graduates of two-year technical degree programs to matriculate into their four-year STEM programs and complete the remaining coursework leading to a BAT or BS degree. The University of Texas at Brownsville (UTB) has adopted this latter innovative approach to increasing student enrollment in STEM …
Influence Of Surface Modification On Corrosion And Biocompatibility Of Titanium Alloys, Zia Ur Rahman
Influence Of Surface Modification On Corrosion And Biocompatibility Of Titanium Alloys, Zia Ur Rahman
Theses and Dissertations - UTB/UTPA
Titanium alloys enhance the quality and longevity of human life by replacing or treating various parts of the body. However, the aggressive body fluids lead to corrosion and metal ions dissolution. These ions leach to the adjacent tissues and causes adverse reactions. Surface modifications improve corrosion resistance and biological activity. In this investigation, electropolishing, magnetoelectropolishing, titanium coating and hydroxyapatite coating were carried out on commercially pure titanium (CPTi), Ti6Al4V and Ti6Al4V-ELI (Extra Low Interstitials). These surface modifications are known to affect surface chemistry, morphology, wettability, corrosion resistance and biocompatibility of these materials. In vitro cyclic potentiodynamic polarization tests were conducted …
Nanostructured Transition Metal Oxides For Energy Storage And Conversion, Qiang Li
Nanostructured Transition Metal Oxides For Energy Storage And Conversion, Qiang Li
Theses and Dissertations - UTB/UTPA
The conventional film configuration of electrochemical electrodes hardly fulfills the high energy and efficiency requirements because heavy electroactive material deposition restricts ion diffusion path, and lowers power density and fault tolerance. In this thesis, I demonstrate that novel nanoarchitectured transition metal oxides (TMOs), e.g. MnO2, V2O5, and ZnO, and their relevant nanocomposites were designed, fabricated and assembled into devices to deliver superior electrochemical performances such as high energy and power densities, and rate capacity. These improvements could be attributed to the significant enhancement of surface area, shortened ion diffusion distances and facile penetration of electrolyte solution into open structures of …
Corrosion Assessment And Enhanced Biocompatibility Analysis Of Biodegradable Magnesium-Based Alloys, Luis Enrique Pompa
Corrosion Assessment And Enhanced Biocompatibility Analysis Of Biodegradable Magnesium-Based Alloys, Luis Enrique Pompa
Theses and Dissertations - UTB/UTPA
Magnesium alloys have raised immense interest to many researchers because of its evolution as a new third generation material. Due to their biocompatibility, density, and mechanical properties, magnesium alloys are frequently reported as prospective biodegradable implant materials. Moreover, magnesium based alloys experience a natural phenomena to biodegrade in aqueous solutions due to its corrosive activity, which is excellent for orthopedic and cardiovascular applications. However, major concerns with such alloys are fast and non-uniform corrosion degradation. Controlling the degradation rate in the physiological environment determines the success of an implant. In this investigation, three grades of magnesium alloys: AZ31B, AZ91E and …
Manufacture And Characterization Of Silver And Copper Nanostructures Produced Via Forcespun Nylon 6 Nanofibers, Wenqian Zhao
Manufacture And Characterization Of Silver And Copper Nanostructures Produced Via Forcespun Nylon 6 Nanofibers, Wenqian Zhao
Theses and Dissertations - UTB/UTPA
Nylon 6 nanofibers were produced using the Forcespinning® method and were deposited with silver or copper thin films using the high vacuum thermal evaporation technique for surface functionalization of nanostructures. The changes in surface composition, morphology and surface energy of native and metallic coated Nylon 6 nanofibers were examined. Their antibacterial properties of native, silver or copper coated Nylon 6 nanofibers were tested. Furthermore, the Nylon 6 nanofibers were used as templates in order to obtain silver or copper nanotubes where the polymer was removed after high temperature calcination. The metallic coated Nylon 6 nanofibers and metallic nanotubes morphology and …
A Decision Support System To Measure Product Suitability For Additive Manufacturing Processes, Cynthia De Vasconcellos Barros
A Decision Support System To Measure Product Suitability For Additive Manufacturing Processes, Cynthia De Vasconcellos Barros
Theses and Dissertations - UTB/UTPA
Additive Manufacturing (AM) technologies started arising around 1980’s and they are currently considered to be the third industrial revolution. With improvements in computers, materials, and automated machines, manufacturers across several types of industries are becoming more familiar with AM processes, and it has become more common to see products that are being fabricated by using this new technology. However, there are still questions regarding when it is suitable to use Additive Manufacturing or conventional manufacturing processes depending on different factors. The purpose of this thesis is to create a Decision Support System (DSS) that will help users measure product suitability …
Bifurcation Type Change Of Ac Electrostatically Actuated Mems Resonators Due To Dc Bias, Dumitru Caruntu, Kyle N. Taylor
Bifurcation Type Change Of Ac Electrostatically Actuated Mems Resonators Due To Dc Bias, Dumitru Caruntu, Kyle N. Taylor
Mechanical Engineering Faculty Publications
This paper investigates the nonlinear response of microelectromechanical system (MEMS) cantilever resonator electrostatically actuated by applying a soft alternating current (AC) voltage and an even softer direct current (DC) voltage between the resonators and a parallel fixed ground plate. The AC frequency is near natural frequency. This drives the resonator into nonlinear parametric resonance. The method ofmultiple scales (MMS) is used to solve the dimensionless differential equation of motion of the resonator and find the steady-state solutions.The reduced order model (ROM) method is used to validate the results obtained using MMS. The effect of the soft DC voltage (bias) component …
Unidirectional Rotary Tendency Of A Wave-Driven Rotor, Yingchen Yang
Unidirectional Rotary Tendency Of A Wave-Driven Rotor, Yingchen Yang
Mechanical Engineering Faculty Publications
Ocean waves can directly drive WECs (wave energy converters) to perform two types of motion—reciprocating motion and unidirectional rotary motion. In general, the efficiency of a reciprocating WEC is strongly wave-frequency dependent, whereas the efficiency of a rotary WEC can be somewhat wave-frequency independent. To date, a huge majority of WEC technologies under development in industry belong to the reciprocating class, and only a few WEC concepts fall in the unidirectional rotary class. In the present work, a wave-driven rotor for unidirectional rotary motion was proposed and characterized. A numerical tool has been developed for characterization of the rotor’s unidirectional …
Mass Production Of Β-Silicon Carbide Nanofibers By The Novel Method Of Forcespinning, Alfonso Salinas
Mass Production Of Β-Silicon Carbide Nanofibers By The Novel Method Of Forcespinning, Alfonso Salinas
Theses and Dissertations - UTB/UTPA
Non-oxide Ceramics such as silicon carbide have very unique properties, for example high toughness, thermal stability, wear resistant, and thermal shock resistance these properties make these ceramic fibers excellent for high temperature applications. Here we present the development of Silicon Carbide nanofibers utilizing a Polystyrene/Polycarbomethylsilane solution as the precursor materials. The Forcespinning ® was performed under a controlled nitrogen environment to prevent fiber oxidation. Characterization was conducted using scanning electron microscopy, x-ray diffraction, and thermogravimetric analysis. The results show successful formation of high yield, long continuous bead-free nanofibers with diameters ranging from 280nm to 2 micron depending on the selected …
Thermal Analysis Of Carbon Nanofiber Reinforced Isotactic Polypropylene, Anna Alicia Hernandez
Thermal Analysis Of Carbon Nanofiber Reinforced Isotactic Polypropylene, Anna Alicia Hernandez
Theses and Dissertations - UTB/UTPA
Isotactic Polypropylene (IPP) is a commonly known thermoplastic that has unique properties include being light weight, high performance, impact strength, tensile strength, elongation, and high temperature properties. The use of vapor grown carbon nanofiber (VGCNF) reinforcements on polypropylene has shown to produce high specific modulus, strength, electrical and thermal properties on specimens. Thermogravimetric (TGA) investigations on the thermal degradation of isotactic polypropylene – vapor grown carbon nanofibers composites in nitrogen were reported. The mass evolution as a function of temperature is a single sigmoid for both polypropylene and polypropylene loaded with VGCNF. The inflection temperature of these sigmoids increases as …