Accession Number : ADA468812


Title :   MURI Center for Materials Chemistry in the Space Environment


Descriptive Note : Final technical rept. 1 May 2001-31 Nov 2006


Corporate Author : CHICAGO UNIV IL DEPT OF CHEMISTRY


Personal Author(s) : Sibener, Steven J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a468812.pdf


Report Date : 30 Nov 2006


Pagination or Media Count : 49


Abstract : MURI research activities, involving strong interactions between experiment and theory, including interactions with AFRL, NASA, and Boeing, have advanced knowledge of condensed-phase and gas-phase reactions relevant to materials reactivity in LEO. We have: elucidated the mechanism by which graphite is eroded by high-kinetic energy atomic oxygen; quantified the pathways by which organic molecules react with atomic oxygen in regimes not found in the terrestrial environment; explored hyperthermal O chemistry with gas-phase model organic compounds to delineate quantum chemical reaction dynamics appropriate to LEO; discovered a new gas-surface collisional energy-transfer mechanism in which atoms become embedded and re-emitted from thin organic films with specific directionality and excess momentum, contributing to a refined understanding of collisional energy transfer; developed new theoretical methodologies for treating rare events which can dominate the morphological evolution of eroding interfaces - including the first three-dimensional code that incorporates realistic interfacial chemical reactions with large surface area processes; explored synergistic effects in polymer degradation involving atomic oxygen and short-wavelength radiation commensurate with LEO solar illumination; collaborated with AFRLs to understand the efficacy of hybrid organic/inorganic POSS materials; and are important partners in orbital experiments, MISSE-5 and -6, which seek to better define materials degradation in LEO.


Descriptors :   *SPACE ENVIRONMENTS , *ENERGY TRANSFER , *POLYMERIC FILMS , *SOLAR RADIATION , *CHEMICAL REACTIONS , SPACECRAFT , QUANTUM CHEMISTRY , HIGH TEMPERATURE , ORGANIC MATERIALS , ORGANIC COMPOUNDS , REACTIVE GASES , MOMENTUM , SHORT WAVELENGTHS , HYBRID SYSTEMS , KINETIC ENERGY , REACTIVITIES , ATOMS , GRAPHITE , MORPHOLOGY , MOLECULES , DEGRADATION


Subject Categories : Physical Chemistry
      Non-electrical Energy Conversion


Distribution Statement : APPROVED FOR PUBLIC RELEASE