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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 30 for “"Dynamic Mechanical Thermal Analysis"”.
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Actuation of shape memory polymer using magnetic fields for applications in medical devices
… of various Nickel Zinc Ferrite particles. Dynamic Mechanical Thermal Analysis (DMTA), tensile strain recovery tests, and Differential Scanning Calorimetry (DSC) were used to measure the mechanical effects of various particle volume contents and sizes on shape memory polymer. These tests …
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I. Solubility and blend studies of nitrocellulose II. Relaxation properties of thin film coatings: the role of surface topography
… for nitrocellulose films. Subsequent dynamic mechanical experiments were then used to evaluate the effectiveness of the blend formulations in broadening the glass transition dispersion of the nitrocellulose blended films; in addition, stress-strain experiments were done in order to …
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Mechanics of amorphous polymers and polymer nanocomposites during high rate deformation
… has been suggested that a polymer's macroscopic mechanical response to a general loading case is governed by its ability to access various primary and secondary molecular mobilities. Specifically, under conditions of high strain rate, restricted secondary molecular motions are thought to bring …
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Durability of fiber-reinforced composite wrap system for the rehabilitation of concrete structures
… of the cylinder.;Coupon level tests consisted of Dynamic Mechanical Thermal Analysis (DMTA) and Tension tests conducted on separate composite coupons that were aged in a similar environment as the cylinders. (Abstract shortened by UMI.).
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Development of hydrophobic thermoplastic starch composites
… of starch-based polymers is limited due to poor mechanical properties. However, it is improved with forming a biocomposite of thermoplastic starch (TPS) as matrix and the cellulose fibers (CF) as reinforcement. The surface of cellulose fibers is successfully modified using the air plasma …
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Blends of Biodegradable Thermoplastics With Lignin Esters
… Blend characteristics were analyzed in terms of thermal and mechanical properties. The results indicate widely different levels of interaction between two polymer constituents. Melt blended samples of CAB/LA and CAB/LB were compatible on a 15-30 nm scale when probed by dynamic mechanical thermal …
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The Effect of Matrix Molecular Weight on the Dispersion of Nanoclay in Unmodified High Density Polyethylene
… g/mol to 460,000 g/mol. X-ray diffraction (XRD), mechanical testing, dynamic mechanical thermal analysis (DMTA), as well as dynamic and capillary rheometry were performed on the nanocomposites. Nanocomposites generated from the high molecular weight (HMW) HDPE matrix exhibited increased …
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Synthesis, properties, and morphology of lignin based epoxy resins
… Additionally, the results of multifrequency dynamic mechanical thermal analysis showed that the lignin containing thermosets have very broad glass transition ranges which most likely were due to transitional phase inhomogeneities and provided these materials with good vibrational damping …
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Fundamental aspects of the tribological behavior of poly(ether-ether-ketone)-based in-situ composites at elevated temperatures
… profiles. These profiles include superior mechanical properties, excellent thermal and dimensional stabilities at high temperatures, and improved melt processabilities. Such characteristics make in-situ composites very attractive as performance polymer-based materials for tribological …
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Effect of photoageing and plasticizer content on the mechanical and adhesive properties of polyvinylbutyral
… objective of this study is to characterize the mechanical and adhesive properties of polyvinylbutyral and determine the effect of plasticizer content and photoageing on these properties. This data would be used to understand how the performance of laminated safety glass is related to the choice …
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Photocrosslinkable polyimide and poly(imide siloxane) homo- and copolymers: synthesis and characterization
… have been characterized for compositional analysis by FT-IR and proton NMR spectroscopy. All polymers were characterized for their thermal properties by differential scanning calorimetry, dynamic mechanical thermal analysis and thermogravimetric analysis. All homoand copolymers possessed …
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Manufacture of and Environmental Effects on Carbon Fiber-Reinforced PhenylEthynyl-Terminated Poly(EtherImide)
… g/mol (3k) PETU led to a survey of CFR 3kPETU mechanical properties for comparison with other high-performance composites. Encouraging results led to a study of moisture sorption effects on CFR 3kPETU properties. The success of these initial studies spawned the large scale production of 2,500 …
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Synthesis and characterization of soluble, melt-processible aromatic poly(amide-imides)
… method has also been made based on molecular, thermal and solid state characterization of the polymers. The synthesis of both high molecular weight as well as controlled molecular weight systems has been attempted. A detailed study of the route employing an acid chloride-anhydride has been …
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Lignin acrylate derivatives and their behaviors in free radical copolymerizations
… derivatives were characterized by elemental analysis, UV, IR, <sup>1</sup>H-NMR, and <sup>13</sup>C-NMR spectroscopy. The acrylated lignin model compounds, guaiacol-IEM urethane (GIU) and hydroxypropyl-guaiacol-IEM urethane (HPGIU), were copolymerized with methyl methacrylate (MMA) and …
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Benign Processing of High Performance Polymeric Foams of Poly(arylene ether sulfone)
… the foaming conditions, both thermogravimetric analysis and differential scanning calorimetery (DSC) were used to determine the solubility and the reduced glass transition temperature (Tg) due to plasticization of the polymer. It was determined that 2 hours was sufficient time to saturate the …
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Investigating the characterisation and stability of polyamide 6,6 in heritage artefacts
… as a method of non?invasive, in situ analysis of contemporary textile material. Besides providing spectral signatures, the advantages of NIR include the non?contact nature of the reflectance technique and the use of a remote, flexible probe. A spectral database of well?defined …
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Cure studies of network-forming polyurethanes
… diphenyl diisocyanate (MDI) was studied via dynamic mechanical thermal analysis (DMTA). HPC/MDI and HPL/MDI resins flow at 30°C and proceed to cure at 50°C. The latter has excellent thermal stability over the former. Crosslinking of HPL and HPC with MDI follow an nth order kinetics, with an …
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Secondary interactions in blends of lignin and cellulose derivatives: composite morphology and properties
Differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were used to characterize the morphology of solvent cast hydroxypropyl cellulose (HPC) films. These techniques revealed the existence of three phases in the bulk material: 1) an amorphous phase, 2) a crystalline …
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Flexure modulus of elasticity in living branch wood
… pin oak (Quercus palustris) samples using a Dynamic Mechanical Thermal Analysis machine from tree trunk to branch tip. This chapter identifies that there is no difference in branch type (primary or secondary) within the variables of MOE, moisture content percent, slenderness ratio, end …
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Multi-scale effects on deformation mechanisms of polymer nanocomposites : experimental characterisation and numerical study
… dramatically enhance its stiffness, strength and thermal properties. The difference between nanocomposites and conventional fibre composites is that the added fillers are extremely small, only one-millionth of a millimetre thick, and provide a much larger interface area per unit volume for greatly …
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