Tesi: "Epoxy compounds"

1

Woo, Shui Cheung. "Degradation of epoxy-clay nanocomposites after UV exposure and moisture attack /". View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?MECH%202006%20WOO.

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2

Hu, Chugang. "Epoxy-clay nanocomposites : morphology, moisture absorption behavior and thermo-mechanical properties /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?MECH%202004%20HU.

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3

Punchaipetch, Prakaipetch. "Epoxy + Liquid Crystalline Epoxy Coreacted Networks". Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2705/.

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Abstract (sommario):

Molecular reinforcement through in-situ polymerization of liquid crystalline epoxies (LCEs) and a non-liquid crystalline epoxy has been investigated. Three LCEs: diglycidyl ether of 4,4'-dihydroxybiphenol (DGE-DHBP) and digylcidyl ether of 4-hydroxyphenyl-4"-hydroxybiphenyl-4'-carboxylate (DGE-HHC), were synthesized and blended with diglycidyl ether of bisphenol F (DGEBP-F) and subsequently cured with anhydride and amine curing agents. Curing kinetics were determined using differential scanning calorimetry (DSC). Parameters for autocatalytic curing kinetics of both pure monomers and blended systems were determined. The extent of cure for both monomers was monitored by using Fourier transform infrared spectroscopy (FT-IR). The glass transitions were evaluated as a function of composition using DSC and dynamic mechanical analysis (DMA). The results show that the LC constituent affects the curing kinetics of the epoxy resin and that the systems are highly miscible. The effects of molecular reinforcement of DGEBP-F by DGE-DHBP and DGE-HHC were investigated. The concentration of the liquid crystalline moiety affects mechanical properties. Tensile, impact and fracture toughness tests results are evaluated. Scanning electron microscopy of the fracture surfaces shows changes in failure mechanisms compared to the pure components. Results indicate that mechanical properties of the blended samples are improved already at low concentration by weight of the LCE added into epoxy resin. The improvement in mechanical properties was found to occur irrespective of the absence of liquid crystallinity in the blended networks. The mechanism of crack study indicates that crack deflection and crack bridging are the mechanisms in case of LC epoxy. In case of LC modified epoxy, the crack deflection is the main mechanism. Moreover, the effect of coreacting an epoxy with a reactive monomer liquid crystalline epoxy as a matrix for glass fiber composites was investigated. Mechanical properties of the modified matrix were determined by tensile, flexural and impact testing. The improvement in toughness of the bulk matrix by the addition of a LCEs is seen also in the composites. The improvement is related to the enhancement of adhesion between the glass fibers and the matrix.

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4

Sgriccia, Nikki. "Microwave and thermally cured natural fiber epoxy composites". Diss., Connect to online resource - MSU authorized users, 2008.

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5

Kelly, Paul Thomas. "Preparation, characterization and properties of montmorillonite/epoxy compounds". Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1057604761.

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6

Bilyeu, Bryan. "Characterization of Cure Kinetics and Physical Properties of a High Performance, Glass Fiber-Reinforced Epoxy Prepreg and a Novel Fluorine-Modified, Amine-Cured Commercial Epoxy". Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4437/.

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Abstract (sommario):

Kinetic equation parameters for the curing reaction of a commercial glass fiber reinforced high performance epoxy prepreg composed of the tetrafunctional epoxy tetraglycidyl 4,4-diaminodiphenyl methane (TGDDM), the tetrafunctional amine curing agent 4,4'-diaminodiphenylsulfone (DDS) and an ionic initiator/accelerator, are determined by various thermal analysis techniques and the results compared. The reaction is monitored by heat generated determined by differential scanning calorimetry (DSC) and by high speed DSC when the reaction rate is high. The changes in physical properties indicating increasing conversion are followed by shifts in glass transition temperature determined by DSC, temperature-modulated DSC (TMDSC), step scan DSC and high speed DSC, thermomechanical (TMA) and dynamic mechanical (DMA) analysis and thermally stimulated depolarization (TSD). Changes in viscosity, also indicative of degree of conversion, are monitored by DMA. Thermal stability as a function of degree of cure is monitored by thermogravimetric analysis (TGA). The parameters of the general kinetic equations, including activation energy and rate constant, are explained and used to compare results of various techniques. The utilities of the kinetic descriptions are demonstrated in the construction of a useful time-temperature-transformation (TTT) diagram and a continuous heating transformation (CHT) diagram for rapid determination of processing parameters in the processing of prepregs. Shrinkage due to both resin consolidation and fiber rearrangement is measured as the linear expansion of the piston on a quartz dilatometry cell using TMA. The shrinkage of prepregs was determined to depend on the curing temperature, pressure applied and the fiber orientation. Chemical modification of an epoxy was done by mixing a fluorinated aromatic amine (aniline) with a standard aliphatic amine as a curing agent for a commercial Diglycidylether of Bisphenol-A (DGEBA) epoxy. The resulting cured network was tested for wear resistance using tribological techniques. Of the six anilines, 3-fluoroaniline and 4-fluoroaniline were determined to have lower wear than the unmodified epoxy, while the others showed much higher wear rates.

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7

Chen, Rong-Sheng. "Hygrothermal response of graphite/epoxy composites /". The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487326511715323.

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8

Chonkaew, Wunpen Brostow Witold. "Modifications of epoxy resins for improved mechanical and tribological performances and their effects on curing kinetics". [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6123.

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9

Chan, Edward King-Long. "A study of moisture diffusion at the epoxy/copper interface for plastic IC packages /". View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?MECH%202006%20CHAN.

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10

Crow, Brian Shelton. "Epoxidation of alkenes by dimethyldioxirane kinetics, activation parameters and solvent studies /". restricted, 2005. http://etd.gsu.edu/theses/available/etd-11282005-140018/.

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Abstract (sommario):

Thesis (Ph. D.)--Georgia State University, 2005.
Title from title screen. Al Baumstark, committee chair; Paul Franklin, David Boykin, Markus Germann, committee members. Electronic text (136 p. : charts (some col.)) : digital, PDF file. Description based on contents viewed June 7, 2007. Includes bibliographical references (p. 130-136).

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11

Zhang, Chi, e 張弛. "Studies on epoxidation of olefins by IN SITU generated N-sulfonyloxaziridine and ruthenium catalyzed oxidative cleavage ofolefins". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242650.

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12

Zhang, Chi. "Studies on epoxidation of olefins by IN SITU generated N-sulfonyloxaziridine and ruthenium catalyzed oxidative cleavage of olefins". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22718667.

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13

Liang, Kaiwen. "Cyanate ester, epoxy and epoxy/cyanate ester matrix polyhedral oligomeric silsesquioxane nanocomposites". Diss., Mississippi State : Mississippi State University, 2005. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.

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14

Chung, Wing-ki. "Reductions using copper hydride and cycloaddition reactions using epoxy enol silanes". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37114207.

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15

Chung, Wing-ki, e 鍾詠琪. "Reductions using copper hydride and cycloaddition reactions using epoxy enol silanes". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37114207.

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16

Lo, Tsz-kiu Brian, e 盧子翹. "Intermolecular [4+3] cycloaddition reactions using epoxy enol silanes". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45877749.

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17

Swadener, John Gregory. "Primary fracture toughness mechanisms of a glass/epoxy interface /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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18

Gregory, Richard Eugene. "An experimental damage tolerance study of low-velocity, high-mass impact and compression after impact responses of locally porous, thin, quasi-isotropic graphite/epoxy laminates : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /". Click to access online version, 2007. http://proquest.umi.com/pqdweb?index=67&did=1394676811&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1255007746&clientId=28564.

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19

Kroetz, Deanna L. "Inhibition of human liver microsomal epoxide hydrolase /". Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/7958.

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20

Norris, Andrew James. "Epoxidized Sucrose Soyate as a Primary Binder in Particleboard". Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29011.

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Abstract (sommario):

Wood composites industry has been growing for decades. However, wood composites have been associated with some health concerns due to the presence of formaldehyde. A promising bio-based resin Epoxidized Sucrose Soyate (ESS) was investigated as a potential primary binder in particleboards. The goal of this research was to find a strong and durable resin for wood composites. Several ESS-MDI based formulas were found that were able to match the performance criteria for particleboard.
North Dakota Soybean Council

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21

Yam, Fei. "Poly-fluorinated metallo-corroles as biomimetic catalyst for epoxidation and H₂O₂-dismutation /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202004%20YAM.

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22

Fraser, Andrew. "Mesoscale behavior of an aluminum-manganese dioxide-epoxy mixture under shock loading: from milli to nano-sized aluminum particles". [Milwaukee, Wis.] : e-Publications@Marquette, 2009. http://epublications.marquette.edu/theses_open/7.

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23

Hartung, Ryan E. "I. Synthesis of saturated, DNA, and RNA spirocyclic-4,4-Nonane nucleosides. II. Studies toward epoxy carbonate formation and the synthesis of suitable precursors III. Methodological investigations involving the reactions of diazomethane with di-, tri-, and tetraketones. IV. Towards the total synthesis of salicifoline". Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1130940224.

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24

Enever, Michael C. N. "Higher olefin epoxidation on silver a combined experimental/theoretical investigation of surface intermediates and reaction mechanisms /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 3.73 Mb., p, 2006. http://proquest.umi.com/pqdlink?did=1172110291&Fmt=7&clientId=79356&RQT=309&VName=PQD.

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25

Zhou, Gang. "Preparation, structure, and properties of advanced polymer composites with long fibers and nanoparticles". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1173287075.

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26

Lukaski, Adrienne Claire. "Investigation of reactions of complex epoxides on silver(110) a combined experimental and theoretical study /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 218 p, 2009. http://proquest.umi.com/pqdweb?did=1654493481&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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27

Javadekar, Ashay Dileep. "Surface science studies of olefin oxidation on the silver surface". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 131 p, 2009. http://proquest.umi.com/pqdweb?did=1889838931&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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28

Rutgers, Lyndal Materials Science &amp Engineering Faculty of Science UNSW. "Development and fracture behaviour of graded alumina/epoxy joins". Awarded by:University of New South Wales. School of Materials Science and Engineering, 2005. http://handle.unsw.edu.au/1959.4/26004.

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Abstract (sommario):

Introduction of a composition gradient at a join between two materials of different elastic properties should reduce the stress concentrating effect of the interfacial discontinuity. A crack oriented perpendicular to this elasticity gradient will experience mode-mixity, and possible subsequent crack deflection. Explicit analytical solutions for the stress state at the tip of an angled crack in a graded material of a given finite geometry do not exist, and ongoing crack path development in such a gradient has not been characterised. An infiltration processing technique is developed which allows two materials to be joined through a region of graded composition, of tailored width and composition profile. Composition discontinuities at layer interfaces in a stepped gradient can be tolerated due to the resulting interpenetrating network structured (INS) microstructure. Firing stresses were found to be a limitation of the processing technique, overcome by limiting the steepness of the elastic gradient. Alumina and epoxy resin graded composites were produced and tested under monotonic loading, resulting in stable crack path evolution. Stress-field asymmetry at the tip of a crack oriented perpendicular to an elastic gradient was demonstrated, followed by subsequent crack deflection. Stress intensity factor and deflection angle increase with increasing gradient steepness. Rising R-curve behaviour was demonstrated for all compositions of the INS composite, with initiation and plateau toughness decreasing with increasing epoxy content. Evidence of crack bridging by intact ligaments of the epoxy phase in the crack wake explains this behaviour. Crack deflection towards the epoxy region was anticipated and demonstrated for all gradient configurations. An increase in relative crack depth was seen to increase mode-mixity at the crack-tip and subsequent crack deflection, up to a relative depth of ~0.5. No conclusive evidence was found for the influence of crack bridging on crack deflection. Toughness was shown to increase with the inclusion of a microstructural gradient. Measured toughness within graded samples was shown to be controlled by both the local composition and the volume of bridging ligaments in the crack wake. The optimum gradient should ??? extend over the widest region practical, ??? encompass the widest composition range possible, and ??? demonstrate extrinsic crack extension toughening.

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29

Rider, Andrew Chemistry Faculty of Science UNSW. "Surface Properties Influencing the Fracture Toughness of Aluminium-Epoxy Joints". Awarded by:University of New South Wales. School of Chemistry, 1998. http://handle.unsw.edu.au/1959.4/17804.

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This thesis systematically investigates the properties of the aluminium adherend which influence the fracture toughness of aluminium-epoxy adhesive joints in humid environments. The fracture energy of the adhesive joint exposed to a humid environment in comparison with the fracture energy in a dry environment provides a measure of the joint durability. A 500C and 95% relative humidity environment is used to simulate aging of an adhesive joint over several years under normal service conditions. Initially, surface roughness is found to have a significant influence on the fracture toughness of the adhesive joint in humid conditions. A direct correlation between the bond durability and the angle of deliberately machined micro-roughness in the aluminium surface is determined. Consequently a model is developed which initially has the capacity to describe the bond durability performance. The preparation of aluminium surfaces involves the use of a novel ultramilling tool to produce well defined and controlled surface topography. This work represents the first time surface angles of features in the 1????m to 10????m range have been systematically varied and a direct relationship with bond durability has been determined. The use of surface analytical tools aids in elucidating mechanisms involved in the failure of the adhesive joint and contributes to the development of the stress based diffusion model. Examination of the aluminium oxide hydration level reveals this property has a negligible effect on the fracture toughness of the aluminium-epoxy joints exposed to humid environments. This information confirms the dominant role of the physical properties of the aluminium surface in determining the adhesive joint durability. This is the first occasion that planer oxide films grown in an RF plasma have had their hydration state adjusted in a controlled manner and their properties subsequently assessed in terms of bond durability properties. Further alteration of the aluminium surface chemistry is achieved through the application of an organo-silane coupling agent and a series of novel organo-phosphonate compounds. This work further develops the stress based diffusion model developed in conjunction with the micro-machining studies. The components of surface roughness and the ability of interfacial bonds to co-operatively share load are essential for the maintenance of fracture toughness of adhesive joints exposed to humid conditions. The ability of the silane coupling agent to share load through a chemically cross-linked film is a significant property which provides the superior fracture toughness in comparison with the phosphonate treated joints. Although the organo-phosphonate treated aluminium provides hydrolytically more stable bonds than the silane coupling agent, the film is not cross-linked via primary chemical bonds and the reduced load sharing capacity of interfacial bonds increases the bond degradation rate. The stress based diffusion model evolving from the initial work in the thesis can be used to predict the performance of more complex systems based on a thorough characterisation of the aluminium surface chemistry and topography. The stress based diffusion model essentially describes the concept of the production of micro-cavities at the epoxy-aluminium interface under mode 1 load, as a result of the distribution of strong and weak adhesive bonds. Alternatively, micro-cavities may result from an inhomogeneous stress distribution. In areas where the adhesive bonds are weak, or the local stresses are high, the interfacial load produces larger micro-cavities which provide a path of low resistance for water to diffuse along the bond-line. The water then degrades the adhesive bond either through the displacement of interfacial epoxy bonds or the hydration of the oxide to form a weak barrier layer through which fracture can occur. Alternatively, the water can hydrolyse the adhesive in the interfacial region, leading to cohesive failure of the epoxy resin. The bond durability performance of a series of complex hydrated oxide films used to pre-treat the aluminium adherend provides support for the stress based diffusion model. Whilst surface area is an important property of the aluminium adherend in producing durable bonding, the best durability achievable, between an epoxy adhesive and aluminium substrate, requires a component of surface roughness which enhances the load sharing capability in the interfacial bonding region. This component of durability performance is predicted by the model. In more specific terms, a boiling water treatment of the aluminium adherend indicates a direct correlation between bond durability, surface area and topography. The characterisation of film properties indicates that the film chemistry does not change as a function of treatment conditions, however, the film topography and surface area does. The overall bond durability performance is linked to both of these properties. The detailed examination of the hydrated oxide film, produced by the boiling water treatment of aluminium, is the first time the bond durability performance has been related to the film topography. It is also the first occasion that the mechanism of film growth has been examined over such a large treatment time. The combination of surface analysis and bond durability measurements is invaluable in confirming the properties, predicted by the stress based diffusion model, which are responsible in forming fracture resistant adhesive bonds in humid conditions. The bond durability of high surface area and low surface area hydrated oxide films indicates that surface area is an important property. However, this study confirms that the absence of the preferred surface topography limits the ultimate bond durability performance attainable. The fracture toughness measurements performed on aluminium adherends pre-treated with a low surface area film also supports the mechanism of load sharing of interfacial adhesive bonds and its contribution to the overall bond durability. The role performed by the individual molecules and particles in an oxide film is similar to the load sharing performed by the silane coupling agent molecules. Further support for the stress based diffusion model is provided by films produced on aluminium immersed in nickel salt solutions. The topography of these film alters as a function of treatment time and this is directly related to fracture toughness in humid environments. This work provides the first instance where such films have been characterised in detail and their properties related to bond durability performance. The study is also the first time that the growth mechanism of the film produced on the aluminium substrate has been examined in detail. The film growth mechanism supports the film growth model proposed for the hydrated oxide film produced by the boiling water treatment. The major findings presented in this thesis are summarised as the direct correlation between surface profile angle, the importance of co-operative load sharing of interfacial adhesive bonds and the relative insignificance of surface oxide hydration in the formation of durable aluminium-epoxy adhesion. This information is used to develop a stress based diffusion model which has the capacity to describe the fracture toughness of a range of aluminium-epoxy adhesive joint systems in humid environments. The stress based diffusion model is also capable of predicting the relative performance of the bond systems examined in the final chapters of the thesis, where complex interfacial oxide films are involved in the formation of adhesive bonds.

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30

Sanderson, James M. "Epoxy matrix composite strain sensing and cure monitoring". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-01102009-063758/.

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31

Lakshminarayanan, Priya V. "EFFECT OF NITRIC ACID OXIDATION ON VAPOR GROWN CARBON FIBERS (VGCFs). USE OF THESE FIBERS IN EPOXY COMPOSITES". MSSTATE, 2003. http://sun.library.msstate.edu/ETD-db/theses/available/etd-08012003-153407/.

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Abstract (sommario):

Pyrograf III^{TM,/sup> fibers (PR-19-PS, Applied Sciences, Inc.) with 100-300 nm diameters and ~ 10-100 ìm lengths were used with a low viscosity aliphatic epoxy resin (Clearstream 9000, Clearstream Products, Inc.) to produce composites. The VGCFs were oxidized in 69-71 wt% nitric acid (115°C) for various times (10 min to 24 h) to modify the surface to enhance fiber/matrix adhesion. Remarkably, little fiber weight loss was detected even after 24 h of oxidation. Composites containing 19.2 volume percent (29.4 weight percent) VGCFs were prepared. Their flexural strengths and flexural moduli were obtained. The flexural strengths did not increase using oxidized VGCFs. Fiber surfaces were characterized using N₂ BET, CO₂ DR, XPS, SEM, TEM and base uptake measurements. Increasing the oxidation time produced only small initial increases in surface area up to a limit. Significant surface oxygen was present before oxidation and the amount increased initially, though not continuously, with nitric acid oxidation.}

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32

Uzunpinar, Cihan Auad Maria Lujan. "Effect of dispersion of SWCNTs on the viscoelastic and final properties of epoxy based nanocomposites". Auburn, Ala., 2010. http://hdl.handle.net/10415/2043.

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33

Tomori, Oluwatosin Oyewole. "Machining of ceramic filled epoxy and its impact on injection mold Applications". Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16901.

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34

Gramoll, Kurt C. "Thermoviscoelastic characterization and predictions of Kelvar/epoxy composite laminates". Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53520.

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This study consisted of two main parts, the thermoviscoelastic characterization of Kevlar 49/Fiberite 7714A epoxy composite lamina and the development of a numerical procedure to predict the viscoelastic response of any general laminate constructed from the same material. The four orthotropic material properties, S₁₁, S₁₂, S₂₂, and S₆₆, were characterized by 20 minute static creep tests on unidirectional ([0]₈, [10]₈, and [90]₁₆) lamina specimens. The Time-Temperature-Superposition-Principle (TTSP) was used successfully to accelerate the characterization process. A nonlinear constitutive model was developed to describe the stress dependent viscoelastic response for each of the material properties. A new numerical procedure to predict long term laminate properties from lamina properties (obtained experimentally) was developed. Numerical instabilities and time constraints associated with viscoelastic numerical techniques were discussed and solved. The numerical procedure was incorporated into a user friendly microcomputer program called Viscoelastic Composite Analysis Program (VCAP), which is available for IBM ‘PC’ type computers. The program was designed for ease of use and includes graphics, menus, help messages, etc. The final phase of the study involved testing actual laminates constructed from the characterized material, Kevlar/epoxy, at various temperature and load levels for 4 to 5 weeks. These results were then compared with the VCAP program predictions to verify the testing procedure (i.e., the applicability of TTSP in characterizing composite materials) and to check the numerical procedure used in the program. The actual tests and predictions agreed, within experimental error and scatter, for all test cases which included 1, 2, 3, and 4 fiber direction laminates. The end result of the study was the development and validation of a user friendly microcomputer program that can be used by design engineers in industry to predict thermoviscoelastic properties of orthotropic composite materials.
Ph. D.

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35

Chonkaew, Wunpen. "Modifications of epoxy resins for improved mechanical and tribological performances and their effects on curing kinetics". Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc6123/.

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Abstract (sommario):

A commercial epoxy, diglycidyl ether of bisphenol-A, was modified by two different routes. One was the addition of silica to produce epoxy composites. Three different silane coupling agents, glycidyloxypropyl trimethoxy silane (GPS), -methacryloxypropyl trimethoxy silane (MAMS) and 3-mercaptopropyltriethoxy silane (MPS), were used as silica-surface modifiers. The effects of silica content, together with the effects of chemical surface treatment of silica, were studied. The results indicate that epoxy composites with silica exhibit mechanical and tribological properties as well as curing kinetics different than the pure epoxy. The optimum silica content for improved mechanical and tribological properties (low friction coefficient and wear rate) was different for each type of silane coupling agent. An unequivocal correlation between good mechanical and improved tribological properties was not found. Activation energy of overall reactions was affected by the addition of silica modified with MAMS and MPS, but not with GPS. The second route was modification by fluorination. A new fluoro-epoxy oligomer was synthesized and incorporated into a commercial epoxy by a conventional blending method. The oligomer functioned as a catalyst in the curing of epoxy and polyamine. Thermal stability of the blends decreased slightly at a high oligomer content. Higher wear resistance, lower friction coefficient and higher toughness were found with increasing oligomer content; thus in this case there was a correlation between good mechanical and improved tribological properties. The results indicated that increasing toughness and formation of a transfer film contribute to improved tribological performances.

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36

Chung, Paular Wai Kwan. "Interfacial adhesion between epoxy molding compound and copper leadframe under different thermal conditions /". View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?MECH%202002%20CHUNGP.

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Abstract (sommario):

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.
Includes bibliographical references (leaves 111-114). Also available in electronic version. Access restricted to campus users.

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37

Gao, Xiao. "Tailored interphase structure for improved strength and energy absorption of composites". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 5.63 Mb., 321 p, 2006. http://proquest.umi.com/pqdlink?did=1172119431&Fmt=7&clientId=79356&RQT=309&VName=PQD.

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38

Gheura, Iuliana L. "Design, synthesis and evaluation of AZA-peptide epoxides as inhibitors of cysteine proteases". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30571.

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39

Liu, Jia. "Polymer-layered silicate nanocomposites : synthesis, structure and properties /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?MECH%202004%20LIU.

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40

Seon, Guillaume. "Finite element-based failure models for carbon/epoxy tape composites". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28117.

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41

DeCoste, Jared B. "Nucleophilic chemistry of faujasite X zeolites with isocyanates, organosulfur esters, and epoxides". Diss., Online access via UMI:, 2009.

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42

Lundin, Angelica. "Quantum chemical studies of olefin epoxidation and benzyne biradicals /". Göteborg, Sweden : Göteborg University, Faculty of Science, 2007. http://www.loc.gov/catdir/toc/fy0801/2007440811.html.

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43

Jayaraman, Krishnan. "Effect of the interphase on the thermo-mechanical response of unidirectional fiber-reinforced epoxies : modeling, analyses and experiments /". Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-02262007-095957/.

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44

Donahue, Matthew G. "Studies toward the synthesis of the C₁₉ quassinoid polyandrane". Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1127227359.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xxiii, 454 p.; also includes graphics (some col.). Includes bibliographical references (p. 246-259). Available online via OhioLINK's ETD Center

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45

Sandberg, Martin. "Mammalian soluble epoxide hydrolase : studies on gene structure and expression /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5747-5.pdf.

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46

Leininger, Wyatt C. "Design and Control of a Micro/Nano Load Stage for In-Situ AFM Observation and Nanoscale Structural and Mechanical Characterization of MWCNT-Epoxy Composites". Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28190.

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Nanomaterial composites hold improvement potential for many materials. Improvements arise through known material behaviors and unique nanoscale effects to improve performance in areas including elastic modulus and damping as well as various processes, and products. Review of research spurred development of a load-stage. The load stage could be used independently, or in conjunction with an AFM to investigate bulk and nanoscale material mechanics. The effect of MWCNT content on structural damping, elastic modulus, toughness, loss modulus, and glass transition temperature was investigated using the load stage, AMF, and DMA. Initial investigation showed elastic modulus increased 23% with 1wt.% MWCNT versus pure epoxy and in-situ imaging observed micro/nanoscale deformation. Dynamic capabilities of the load stage were investigated as a method to achieve higher stress than available through DMA. The system showed energy dissipation across all reinforce levels, with ~480% peak for the 1wt.% MWCNT material vs. the neat epoxy at 1Hz.
ND NASA EPSCoR FAR0017788
NDSU Development Foundation FAR0017503
National Science Foundation (NSF) Grant# HRD-0811239 to the NDSU Advance FORWARD Program

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47

Butzloff, Peter Robert. "Preparation and Characterization of a Treated Montmorillonite Clay and Epoxy Nanocomposite". Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2729/.

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Montmorillonite reinforced polymers are a new development in the area of nanocomposite materials. Since reinforcement of epoxy is important to the development of high strength adhesives and composite matrices, the introduction of montmorillonite to epoxy is of interest. Compositional effects on epoxy reactivity, on molecular relaxation, and on mechanical properties were investigated. Change in reactivity was determined by Differential Scanning Calorimetry. Tensile properties at room temperature indicated improved modulus and retention of strength of the epoxy matrix but a decreased elongation to failure. Depression of dry nanocomposite glass transition was observed for nanocomposites beyond 5% by weight montmorillonite. Samples that were saturated with water showed lower moduli due to the epoxy matrix. The greatest moisture absorption rate was found at 7%, the least at 3%.

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48

Miller, William V. "Ultrasound detection using singlemode optical fibers with applications to epoxy cure monitoring". Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42215.

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The state of cure of epoxies is an important issue in the manufacture of graphite epoxy composites used in aerospace structures. Variations in the initial state and process used to cure the epoxy resin in a composite material lead to variations in the mechanical properties of the part manufactured from the composite._[12] Control of these variation can be accomplished by monitoring the bulk and shear moduli of the epoxy resin as it cures. The moduli properties of the resin determine the acoustic properties of the epoxy._{[12],[13],[14]} Hence measurement of the acoustic longitudinal velocity and attenuation of the epoxy during its cure cycle provides a good indicator of the state of cure. Optical fiber waveguides can be embedded within a host material and used to detect longitudinal acoustic waves._[15],[16] Herein, the mechanisms allowing the detection of ultrasound with optical fiber are presented. An analysis of optical fiber waveguides and optical fiber based interferometric detection methods is performed in detail. The interaction of radial strain fields, induced by longitudinal acoustic waves, with singlemode optical fibers is described. Experimental results obtained in epoxy cure monitoring, using an optical fiber based method for acoustic detection, are compared with results obtained using conventional piezoelectric based acoustic detection methods.
Master of Science

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49

Tymichova, Michaela. "Relation between toughness and molecular coupling at cross-linked polymer/solid interfaces". Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060712.125012/index.html.

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50

Kim, Young-Min MacGregor John Frederick. "Photopolymerization of cycloaliphatic epoxide and vinyl ether /". *McMaster only, 2005.

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Tesi sul tema "Epoxy compounds"

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