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Full-Text Articles in Engineering

Progress Toward Durable Icephobic Materials, Matthew J. Coady Oct 2019

Progress Toward Durable Icephobic Materials, Matthew J. Coady

Electronic Thesis and Dissertation Repository

Ice accumulation is a major engineering challenge in many fields including aerospace, power generation, transportation, and infrastructure. A variety of solutions are being researched to address this challenge. Perhaps the most promising method of combating ice accumulation is by applying coatings with low values of interfacial ice adhesion strength, τice. Icephobic materials are those with ice adhesion below 100 kPa, and it has been shown that passive delamination can occur on surfaces with τice below 20 kPa. While various low adhesion surfaces have been prepared, durability concerns pervade applications where surfaces experience repeated icing or freeze-thaw cycles, mechanical ...


A Ph-Sensitive Delivery System For The Prevention Of Dental Caries Using Salivary Proteins, Yi Zhu May 2019

A Ph-Sensitive Delivery System For The Prevention Of Dental Caries Using Salivary Proteins, Yi Zhu

Electronic Thesis and Dissertation Repository

Dental caries remains one of the most common chronic diseases worldwide. Salivary proteins such as histatins have demonstrated biological functions directly related to tooth homeostasis and prevention of dental caries. However, histatins are susceptible to the high proteolytic activities in the oral environment. Therefore, pH-sensitive chitosan nanoparticles (CNs) have been proposed as potential carriers to target major oral diseases that occur under acidic conditions (e.g. dental caries and dental erosion). Four different types of chitosan polymers were investigated and the optimized CNs successfully loaded histatin 3 and released it selectively under acidic conditions. Through loading the survival time of ...


Chemical Modification Of Lignin Into Advanced Materials, Soheil Hajirahimkhan Aug 2018

Chemical Modification Of Lignin Into Advanced Materials, Soheil Hajirahimkhan

Electronic Thesis and Dissertation Repository

Fossil fuel resources are being used today for most of humankind’s energy and chemical/material needs. The inevitable demise of these resources has created significant interest in the field of biomass and particularly, lignin valorization. As the world’s second most abundant polymer, more than 98% of the annually produced lignin is under-utilized either as an on-site heat source, or as landfill. Thus, finding practical approaches to modifying this inexpensive sustainable resource into materials of high value can be the next leap in lessening the dependence on fossil fuel resources and thus, developing a sustainable future.

In this thesis ...


Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan Aug 2018

Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan

Electronic Thesis and Dissertation Repository

The use of nitrogen-based fertilizers continues to accelerate with human population growth and increases in global food requirements. Enhanced efficiency fertilizers (EEFs) have been developed to improve the synchronization between nutrient supply and crop nutrient demand. However, many of the current controlled release fertilizers are coated with non-degradable polymers that contribute to accumulation of microplastics within ecosystems. This thesis describes research towards the development of a new class of fertilizer coatings using a self-immolative polymer known as poly (ethyl glyoxylate) (PEtG). PEtG itself does not have suitable properties to produce a viable coating but once blended with another degradable polyester ...


Direct Sheet Molding Compound Process (D-Smc), Atieh Motaghi Feb 2018

Direct Sheet Molding Compound Process (D-Smc), Atieh Motaghi

Electronic Thesis and Dissertation Repository

The combination of highly crosslinked resin and long glass fiber reinforcement in direct sheet molding compound (D-SMC) provides the parts with high physical properties and low density suitable for large interior and exterior automotive applications. Different stages of D-SMC process including maturation zone and compression molding are studied using mathematical analysis, numerical simulation and experimental investigations.

An analytical analysis is used to calculate the pressure and velocity in the first section of maturation zone and then the permeability of fiber bundle is calculated by simulation and the agreement between the available empirical equation and simulation was obtained. The flow is ...


Adaption Of Catechol And Reversible Addition-Fragmentation Chain-Transfer (Raft) Chemistries For Water-Based Applications, Olabode Oyeneye Dec 2017

Adaption Of Catechol And Reversible Addition-Fragmentation Chain-Transfer (Raft) Chemistries For Water-Based Applications, Olabode Oyeneye

Electronic Thesis and Dissertation Repository

Incorporating the binding chemistry of catechol functionality with RAFT chemistry offers a facile and simplified approach for developing a suite of new 2D and 3D hybrid materials with tailored morphologies. Leveraging both chemistries by synthesizing catechol-end functionalized RAFT agents and catechol-containing monomeric species for RAFT (co)polymerization, this dissertation examined a new series of advanced materials that were designed for water-based applications including model flocculants, thermoresponsive hydrogels, adsorbents and underwater adhesives.

To prepare the RAFT agents, novel trithiocarbonates with several catechol end R groups (as postpolymerization anchors) were synthesized that differ in their carbonyl α-substituents (Dopa-CTAs). These materials were evaluated ...


Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen Apr 2017

Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen

Electronic Thesis and Dissertation Repository

In order to enhance both the photoactivity and physical/mechanical properties of titania/polyurethane (PU) nanocomposites, in-situ polymerization and film casting were investigated. Both self-degrading PU foams and self-cleaning PU coatings were prepared. Functional monomers were prepared usingDMPA (2,2-dimethylolpropionic acid) functionalized anatse TiO2 and P25 for integration into polyurethane foam with a "grafting-from" synthetic method. This technique was found to successfully reduce the agglomeration effect of titania nanoparticles inside the foams. In addition, the photodegradation rate was enhanced by > 120% over unmodified foam at an optimized loading of 3wt% DMPA functionalized anatase TiO2. The presence of DMPA ...


In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson Dec 2016

In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson

Electronic Thesis and Dissertation Repository

Long Fiber Thermoplastics (LFT) are promising new materials with high physical properties and low density. These high properties are obtained by embedding very long fibers (~100 mm) into a thermoplastic matrix. Such a high fiber length dictates the use of a compression molding process for manufacturing as the length of discontinuous fibers in injection molding is limited by pellet length.

LFT composites are of great interest for the automotive industry. These materials are already used in some interior and exterior car parts such as bumpers, seat structures, door module etc. This research is inspired by the desire to manufacture load ...


Controlled Delivery Of Angiogenic And Arteriogenic Growth Factors From Biodegradable Poly(Ester Amide) Electrospun Fibers For Therapeutic Angiogenesis, Somiraa S. Said Aug 2016

Controlled Delivery Of Angiogenic And Arteriogenic Growth Factors From Biodegradable Poly(Ester Amide) Electrospun Fibers For Therapeutic Angiogenesis, Somiraa S. Said

Electronic Thesis and Dissertation Repository

Therapeutic angiogenesis relies on the delivery of exogenous growth factors to stimulate neovessel formation. However, systemic administration of angiogenic factors results in rapid clearance from the site of interest due to their short biological half-life. In this work, we are reporting controlled delivery of a ‘cocktail’ of growth factors, an angiogenic factor −fibroblast growth factor-2 (FGF2), and an arteriogenic factor −fibroblast growth factor-9 (FGF9), from biodegradable poly(ester amide) (PEA) electrospun fibers towards targeting neovascular formation and maturation. FGF2 and FGF9 were dual loaded into PEA fibers using a mixed blend and emulsion electrospinning technique. Matrigel tube formation and Boyden ...


Fractionation Of Cornstalk Into Cellulose And Lignin For The Production Of Sodium Carboxymethyl Cellulose, Tao Shui Aug 2016

Fractionation Of Cornstalk Into Cellulose And Lignin For The Production Of Sodium Carboxymethyl Cellulose, Tao Shui

Electronic Thesis and Dissertation Repository

This thesis project aimed to fractionate cornstalk into cellulose and lignin, and utilize the crude cornstalk-derived cellulose for the production of sodium carboxymethyl cellulose and the lignin for the sybthesis of bio-based phenol-formaldehyde resole resins as wood adhesives. In this thesis work, cornstalk was efficiently fractionated into crude cellulose and crude lignin in mixed solvents of acetic acid, formic acid and water at a solid/agent ratio of 1:5 (g/mL) at 80-100 °C for 120-240 min. The best conditions for organosolv fractionation of cornstalk among the test conditions were determined as follows: mixed solvent of acetic acid/formic ...


Studies On Nanocomposite Coating Produced By Laser-Assisted Process To Prevent Silicone Hydrogels From Bio-Fouling, Vishnuvardhana Wuppaladhodi Aug 2016

Studies On Nanocomposite Coating Produced By Laser-Assisted Process To Prevent Silicone Hydrogels From Bio-Fouling, Vishnuvardhana Wuppaladhodi

Electronic Thesis and Dissertation Repository

In this thesis, silver nanoparticles incorporated into polyvinylpyrrolidone (PVP) were deposited on silicone hydrogel to improve the hydrophilicity of the silicone hydrogel and prevent the growth of bacteria. Two different processes were employed to produce Ag nanoparticles: (1) Process-A is a photochemical reduction; (2) Process-B is laser ablation in liquid. Following that, MAPLE process was employed to deposit the Ag-PVP nanocomposites on the surface of silicone hydrogel. A solid-state pulsed laser (Nd:YAG) with a wavelength of 532 nm at a fluence of 50.4 mJ/cm2 was used in the MAPLE system to deposit Ag-PVP nanocomposite coating. Our ...


Production Of Bio-Based Phenol Formaldehyde Foams, Bing Li Jul 2016

Production Of Bio-Based Phenol Formaldehyde Foams, Bing Li

Electronic Thesis and Dissertation Repository

Considering the declining non-renewable fossil resources, there is increasing interest in the development of more environmentally conscious, sustainable and cost-effective substitutes for chemical production. Lignin, a main component in lignocellulosic biomass, has been considered to be a potential substitute for petroleum-based phenol due to its phenolic structure.

This PhD dissertation aimed at producing bio-based phenol formaldehyde (BPF) foams using bio-phenols, including but not limited to, kraft lignin (KL), organosolv lignin (OL), hydrolysis lignin (HL), and bio-crude oil from white birth bark. The challenge of the existing process of producing BPF foams is that a low phenol substitution ratio, generally less ...


Polymer System And Molding Techniques For Surgical Training Models, Daniel J. Park Apr 2016

Polymer System And Molding Techniques For Surgical Training Models, Daniel J. Park

Electronic Thesis and Dissertation Repository

Poly(vinyl alcohol) (PVA) hydrogels are used to produce high fidelity models for surgical training applications. PVA hydrogel mechanical properties are developed through the use of a freeze-thaw cycling, physical crosslinking process. The resulting gels exhibit a non-linear elastic modulus which can be tailored to match many tissues of the human body.

Methods for joining PVA hydrogels were investigated to aid in the production of complicated structures that would be difficult to produce in a single step. Bond strength of PVA gels was characterized using a modified peel test. The porosity and degree of crosslinking of the PVA substrate were ...


Engineered Quantum Dots For Eva Nanocomposite Films And Tio2 Photocatalysts, Md Abdul Mumin Apr 2016

Engineered Quantum Dots For Eva Nanocomposite Films And Tio2 Photocatalysts, Md Abdul Mumin

Electronic Thesis and Dissertation Repository

Light absorbing inorganic nanoparticles in transparent plastics such as poly(ethylene-co-vinyl acetate) (EVA) are of enormous interest in emerging solar materials, including photovoltaic (PV) modules and commercial greenhouse films. Quantum dots (QDs) have the potential to absorb UV light and selectively emit visible light. However, how to stabilize the QDs for long product life spans without "blinking" while enabling their easy integration into polymer systems is lacking. This work examines different approaches for loading mesoporous silica encapsulated QDs into EVA polymer films which can control plant growth in greenhouses or enhance PV panel efficiencies.

Highly luminescent CdS and CdS-ZnS core-shell ...


Design And Implementation Of Multi-Responsive Azobenzene Triggers In Self-Immolative And Degradable Polymers, Andrew D. Wong Mar 2016

Design And Implementation Of Multi-Responsive Azobenzene Triggers In Self-Immolative And Degradable Polymers, Andrew D. Wong

Electronic Thesis and Dissertation Repository

Self-immolative polymers are a recently developed class of degradable polymers capable of undergoing end-to-end depolymerization following the reaction of their endcaps with appropriate stimuli. Self-immolative materials originated in the field of prodrug chemistry, and evolved into self-immolative oligomers, dendrimers, and most recently, linear polymers. Many stimuli-responsive endcaps have been developed, but typically can only respond to one stimulus. Azobenzenes are a well-known class of stimuli-responsive molecules most commonly used as photoswitches, due to their facile trans-cis isomerization. In addition to their photochemistry, azobenzenes have recently been found to be selectively reduction-sensitive, and are therefore of interest as endcaps in ...


Investigation And Modeling Of Dip-Coating Process For Dispersions, Mahyar Javidi Soufiani Feb 2016

Investigation And Modeling Of Dip-Coating Process For Dispersions, Mahyar Javidi Soufiani

Electronic Thesis and Dissertation Repository

Dip coating of liquid film deposition on cylindrical substrates is studied using mathematical modeling, numerical simulation and experimental investigation. A mathematical model based on the Landau-Levich approach for dip coating has been developed using the Ellis constitutive equation, for cylindrical geometries, to analyze the effects on the coating thickness of the substrate radius and hydrodynamic behavior for a non-Newtonian fluid. The influence of the viscosity at low shear rates near the surface of the withdrawal film is included in the Ellis model and coating thickness results for Ellis, power law and Newtonian models are compared with experimental data. Good agreement ...


Slope Stability Enhancement Of An Upstream Tailings Dam: Laboratory Testing And Numerical Modelling, Yazeed A. Alsharedah Dec 2015

Slope Stability Enhancement Of An Upstream Tailings Dam: Laboratory Testing And Numerical Modelling, Yazeed A. Alsharedah

Electronic Thesis and Dissertation Repository

Mine tailings are the byproduct of mining activities, which need to be disposed of once the ore is extracted. They can be disposed of in either dry or wet forms. The latter is most common with the tailings being disposed of in the form of slurry inside retention structures. The retention structure may be a natural, manmade, or built dam, which is the case in most of nowadays mining locations. In this thesis, improving the stability of an upstream tailings dam using soil additives is investigated. The experimental phase of this study involved laboratory tests conducted to characterize mine tailings ...


Catalytic Conversion Of Glycerol To Value-Added Chemical Products, Malaya Ranjan Nanda Sep 2015

Catalytic Conversion Of Glycerol To Value-Added Chemical Products, Malaya Ranjan Nanda

Electronic Thesis and Dissertation Repository

Rapid expansion of biodiesel industry has generated a huge amount of crude glycerol. This thesis aimed to explore utilization of glycerol for the production of solketal as an oxygenated fuel additive and 1, 2-propanediol as a pre-polymer via catalytic conversion.

The thesis work may be divided into two major parts. In the first part, the thermodynamics and kinetics of the glycerol ketalization for the synthesis of solketal were investigated in a batch reactor. From this information, a continuous-flow process was designed, developed and optimized using pure glycerol. Crude glycerol (13 wt% purity) was successfully upgraded into a purified crude glycerol ...


Synthesis, Characterization And Applications Of Lignin-Based Epoxy Resins, Fatemeh Ferdosian Apr 2015

Synthesis, Characterization And Applications Of Lignin-Based Epoxy Resins, Fatemeh Ferdosian

Electronic Thesis and Dissertation Repository

Epoxy resin is one of the most versatile thermosetting polymers with diverse applications. Epoxy resins are mainly produced from the reaction of bisphenol-A (BPA) and epichlorohydrin. The consumption of bisphenol-A is facing growing concerns over its carcinogenic effects and its sustainability. Lignin can be a promising renewable substitute of bisphenol-A in the synthesis of epoxy resins.

In this thesis work, a novel method has been developed for the synthesis of bio-based epoxy resins with reduced side reactions, employing de-polymerized lignin from organosolv lignin (DOL), kraft lignin (DKL) and hydrolysis lignin (DHL) under alkaline condition in the presence of a phase ...


Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang Dec 2014

Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang

Electronic Thesis and Dissertation Repository

The phenol-formaldehyde (PF) resin manufacturing industry is facing a growing challenge with respect to concerns over human health, due to the use of carcinogenic formaldehyde and sustainability due to the use of petroleum-based phenol in PF resin manufacture. Glucose and its derivative, 5-hydroxymethylfurfural (5-HMF), have proven to be potential substitutes for formaldehyde in the synthesis of phenolic novolac resins.

This thesis investigated a number of glucose and 5-HMF resin systems including the curing of phenol-glucose novolac resin (PG) with a bis-phenol-A type epoxy. The curing process was modeled according to the Sestak-Berggren equation (S, B) using Málek methods. This was ...


Laser-Assisted Surface Modification Of Hybrid Hydrogels To Prevent Bacterial Contamination And Protein Fouling, Guobang Huang Aug 2014

Laser-Assisted Surface Modification Of Hybrid Hydrogels To Prevent Bacterial Contamination And Protein Fouling, Guobang Huang

Electronic Thesis and Dissertation Repository

Silicone hydrogels have been extensively studied in the fields of contact lenses, tissue engineering, and drug delivery due to their good biocompatibility, high oxygen permeability, and proper light transmission. However, their applications in biomedical devices are limited by protein adsorption and bacterial contamination because of the hydrophobic surface of silicone, which will cause more irreversible protein adsorption. Several physical methods can be applied to create a hydrophilic surface on hydrogels, such as spin coating, physical vapor deposition, dip coating, drop casting, etc. Compared to the conventional methods, the matrix assisted pulsed laser evaporation (MAPLE) is suitable to produce biopolymer/polymer ...


Synthesis, Properties, And Applications Of Carboxylic Acid Functionalized Polyisobutylene, Inderpreet Sran Aug 2014

Synthesis, Properties, And Applications Of Carboxylic Acid Functionalized Polyisobutylene, Inderpreet Sran

Electronic Thesis and Dissertation Repository

Polyisobutylene (PIB) and its copolymers are used in a wide range of commercial products owing to their high chemical stability, impermeability, elasticity, and biocompatibility. In this thesis, linear and arborescent PIB containing small percentages of isoprene (IP) were functionalized to provide different derivatives and their physical and biological properties were studied.


Humidity Effect On The Structure Of Electrospun Core-Shell Pcl-Peg Fibers For Tissue Regeneration Applications, Adam P. Golin Apr 2014

Humidity Effect On The Structure Of Electrospun Core-Shell Pcl-Peg Fibers For Tissue Regeneration Applications, Adam P. Golin

Electronic Thesis and Dissertation Repository

With the aim of creating a biodegradable scaffold for tympanic membrane (TM) tissue regeneration, core-shell nanofibers composed of a poly(caprolactone) shell and a poly(ethylene glycol) core were created using a coaxial electrospinning technique. In order to create fibers with an optimal core-shell morphology, the effect of relative humidity (RH) on the core-shell nanofibers was systematically studied, with a FITC-BSA complex encapsulated in the core to act as a model protein. The core-shell nanofibers were electrospun at relative humidity values of 20, 25, 30, and 40% RH within a glove box outfitted for humidity control. The core-shell morphology of ...


Characterization Of Fine Powders And Development Of Processes For Powder Coatings, Jing Fu Apr 2014

Characterization Of Fine Powders And Development Of Processes For Powder Coatings, Jing Fu

Electronic Thesis and Dissertation Repository

Traditional powder coating provides poor coating appearance. Fine powder coating can overcome this drawback since the smaller powder particles lead to much smoother finish. Nevertheless, fine powder has been experienced to cause more application problems. This study investigated fine powder coatings from different aspects and it provided solutions to solve these application problems.

The investigation on fine powders conducted by this study concluded that the medium particle size and D10 was not suitable for the flowability characterization of fine powder coatings. Instead, an index which represented the particle size distribution could correlate with the flowabilities of the fine powder ...


Antibacterial Studies On Titania Polyurethane Nanocomposite Coatings, Koosha Azhie Apr 2014

Antibacterial Studies On Titania Polyurethane Nanocomposite Coatings, Koosha Azhie

Electronic Thesis and Dissertation Repository

While temporary disinfection of a surface is possible with the help of strong cleaners, tremendous interest exists for the control of microorganisms on surfaces by effective, durable antimicrobial coatings. There is a wide spectrum of potential applications for antibacterial coatings, spanning from industrial surface coatings to biomedical applications, where sterile conditions are crucial. This work examined the synthesis of the functionalized 2,2-Dimethylolpropionic acid - nanotitanium dioxide (DMPA-nTiO2) monomer. Moreover, functionalized nanotitanium dioxide/polyurethane (nTiO2/PU) composite coatings were prepared using the above mentioned functionalized monomer. The distribution of nTiO2 in the polymer matrix was enhanced by monomer ...


Production Of Lignin-Based Phenolic Resins Using De-Polymerized Kraft Lignin And Process Optimization, Homaira Siddiqui Dec 2013

Production Of Lignin-Based Phenolic Resins Using De-Polymerized Kraft Lignin And Process Optimization, Homaira Siddiqui

Electronic Thesis and Dissertation Repository

Commercialization of Lignin-based phenol formaldehyde resins (LPF) has been limited due to the increase in curing temperatures and decrease in adhesive strength of LPF compared to conventional phenolic resins. Lignin depolymerization can increase the reactivity of lignin; however, the effect of lignin molecular weight on curing performance of LPF resins has yet to be investigated. This research work examined the optimization of synthesis parameters including percent substitution of phenol with lignin, formaldehyde- to-phenol ratio (F/P), and Mw of lignin to reduce the curing temperature and increase the adhesive strength of LPF. DSC analysis indicated that lignin with Mw ~1200g ...


Effects Of Biodiesel Concentration On Microbial Deterioration Of Polyethylene In A Simulated Fuel Storage Tank, Juan Manuel Restrepo-Florez Dec 2013

Effects Of Biodiesel Concentration On Microbial Deterioration Of Polyethylene In A Simulated Fuel Storage Tank, Juan Manuel Restrepo-Florez

Electronic Thesis and Dissertation Repository

In this study a simulated fuel storage tank was used to investigate the effect of biodiesel concentration on biodegradation of polyethylene. This research is relevant in the field of fuel storage. The simulated storage system consisted of a number of identical conical flasks. Each flask was comprised of two layers, an upper one consisting of a fuel blend of diesel with biodiesel in concentrations ranging from 0 to 100% of biodiesel and the bottom layer containing an aqueous mineral media inoculated with a community obtained from a real fuel storage facility. Polyethylene slabs cut to a specific size were immersed ...


Electrospinning Of Core-Shell Collagen Nanofibers, Ying Li Aug 2013

Electrospinning Of Core-Shell Collagen Nanofibers, Ying Li

Electronic Thesis and Dissertation Repository

In tissue engineering, the scaffold plays a critical role in guiding and supporting cells to function and grow optimally. The electrospun nanofibrous scaffold can serve as a near ideal substrate for tissue engineering because it has high surface area and the three-dimensional interconnected porous network can enhance cell attachment and proliferation. Core-shell nanofibrous scaffolds produced with coaxial electrospinning allow bioactive molecule encapsulation to improve cell adhesion, mediate and promote the proper signaling among the cells for their functioning and growth. In the current study, core-shell collagen nanofibers were fabricated via coaxial electrospinning with horizontal and vertical configurations. Core-shell nanofibers with ...


Degradation Kinetics And Functional Design Of Linear Self-Immolative Polymers, Ryan A. Mcbride Jun 2013

Degradation Kinetics And Functional Design Of Linear Self-Immolative Polymers, Ryan A. Mcbride

Electronic Thesis and Dissertation Repository

Linear self-immolative polymers display a potential to address many of the limitations in the control over the degradation process in traditional biodegradable polymers. These materials are unique relative to most degradable 
polymers, in that they undergo end-to-end depolymerization in
 response to the cleavage of a stabilizing end-capping agent. Although one of their cited 
attributes is a dependence of their degradation time on chain length, no conclusive study has been conducted to demonstrate and study this 
effect. Using a previously reported linear self-immolative backbone derived from alternating 4-hydroxybenzyl alcohol and N,N’-dimethylethylenediamine spacers, this work offers the first conclusive study ...


Butyl Rubber-Aliphatic Polyester Graft Copolymers For Biomedical Applications: Synthesis And Analysis Of Chemical, Physical And Biological Properties, Bethany A. Turowec Jun 2013

Butyl Rubber-Aliphatic Polyester Graft Copolymers For Biomedical Applications: Synthesis And Analysis Of Chemical, Physical And Biological Properties, Bethany A. Turowec

Electronic Thesis and Dissertation Repository

Biomaterials can be used in a wide variety of medical applications owing to their breadth of characteristics that can be imparted by varying their chemical structures. Butyl rubber (IIR), which is a copolymer of isobutylene (IB) and small percentages of isoprene (IP), is particularly attractive as a biomaterial because of its elastomeric mechanical properties, biocompatibility, impermeability and high damping characteristics. IIR is typically vulcanized through chemical-based crosslinking mechanisms. However, these methods are not acceptable for biological applications. This thesis focuses on the synthesis of IIR-polyester graft copolymers by grafting biodegradable and biocompatible polyesters including poly(caprolactone) (PCL) and poly(d ...