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Polymer and Organic Materials Commons

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Full-Text Articles in Polymer and Organic Materials

Tensile Properties And Fatigue Behavior Of Geopolymer Matrix Composites With Carbon Fiber Reinforcement At Elevated Temperature, Steffan M.L. Wilcox Mar 2018

Tensile Properties And Fatigue Behavior Of Geopolymer Matrix Composites With Carbon Fiber Reinforcement At Elevated Temperature, Steffan M.L. Wilcox

Theses and Dissertations

The tensile stress-strain and tension-tension fatigue of geopolymer matrix composites reinforced with 0/90 carbon fibers was investigated at 23 and 300°C in laboratory air. Geopolymers are inorganic polymeric materials composed of alumina, silica, and alkali metal oxides. Because geopolymers are synthesized as a fluid mixture or particles and liquid, they can be cast into a desired shape, and cured at only slightly elevated temperatures. The relative ease of synthesis and low processing temperatures make geopolymers an attractive choice as a matrix material for composite materials. Geopolymers also offer resistance to heat and oxidizing environments. Currently, geopolymer matrix composites are being …


Degradation Of Carbon Fiber Reinforced Polymer And Graphite By Laser Heating, Nicholas C. Herr Sep 2016

Degradation Of Carbon Fiber Reinforced Polymer And Graphite By Laser Heating, Nicholas C. Herr

Theses and Dissertations

The availability of high power, diode pumped solid state and fiber lasers at powers 10 kW and shorter wavelengths (1.07 micrometer) has invigorated the development of tactical laser weapons. This shift to tactical missions greatly increases the variety of potential targets including carbon fiber reinforced polymers and related materials. The complexity of laser-material interactions has driven a historical reliance on live-fire testing and empirical models, but this becomes more difficult as the number of target materials grow. This dissertation combines thermal imagery and existing thermal models of the fire response of composite materials to develop a hybrid modeling approach of …


An Analytical Model Of Nanometer Scale Viscoelastic Properties Of Polymer Surfaces Measured Using An Atomic Force Microscope, Jacob B. Goldberg Mar 2011

An Analytical Model Of Nanometer Scale Viscoelastic Properties Of Polymer Surfaces Measured Using An Atomic Force Microscope, Jacob B. Goldberg

Theses and Dissertations

The United States Air Force and the Department of Defense is increasingly interested in nanomaterials. To study these materials, one needs to measure the mechanics of materials on the nanoscale. Over the past few decades the atomic force microscope (AFM) has been used in various methods to establish local surface properties at the nanoscale. In particular, surface elasticity measurements are crucial to understanding nanoscale surface properties. Problems arise, however, when measuring soft surfaces such as polymers and biological specimens, because these materials have a more complex viscoelastic response. This research focuses on modeling an AFM dynamic nanoindentation experiment intended to …


High Temperature Degradation Of 5250-4 Polymer Resin, Patrick E. Link Jun 2007

High Temperature Degradation Of 5250-4 Polymer Resin, Patrick E. Link

Theses and Dissertations

5250-4 bismaleimide resin is used in high performance polymer matrix composites with high temperature aeronautical applications. This thesis investigated the thermal and oxidative degradation of 5250-4 neat resin powder in argon, air, and oxygen environments. The powder was aged at 163 deg. C, 177 deg. C, and 190 deg. C in all environments for at least 250 hours. Isothermal thermo-gravimetric analysis demonstrated that weight loss was negligible for aging in the argon environment, indicating weight loss is the result of an oxidative process at these temperatures. The 5250-4 powder exhibited an initial period of weight gain before eventually losing weight …