Issue 10 Volume 41 May 16, 2003

20030037128 Geological Survey, Reston, VA
Cobalt Recycling in the USA in 1998
Shedd, K.; 2002; 22 pp.
Report No.(s): PB2003-102704; USGS-OFR-02-299; No Copyright; Avail: CASI; A03, Hardcopy
This report is one of a series of reports on metals recycling. It defines and quantifies the 1998 flow of cobalt-bearing
materials in the USA, from imports and stock releases through consumption and disposition, with particular emphasis on the
recycling of industrial scrap (new scrap) and used products (old scrap). Because of cobalts many and diverse uses, numerous
types of scrap were available for recycling by a wide variety of processes. In 1998, an estimated 32 percent of U.S. cobalt
supply was derived from scrap. The ratio of cobalt consumed from new scrap to that from old scrap was estimated to be 50:50.
Of all the cobalt in old scrap available for recycling, an estimated 68 percent was either consumed in the USA or exported
to be recycled.
NTIS
Cobalt; Recycling; Scrap
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NONMETALLIC MATERIALS
Includes physical, chemical, and mechanical properties of plastics, elastomers, lubricants, polymers, textiles, adhesives, and ceramic
materials. For composite materials see 24 Composite Materials.
20030032312 NASA Glenn Research Center, Cleveland, OH, USA
NMR Guided Design of Endcaps With Improved Oxidation Resistance
Meador, Mary Ann B.; Frimer, Aryeh A.; [2002]; 2 pp.; In English; 2002 Spring National ACS Meeting, 23-28 Mar. 2003,
New Orleans, LA, USA
Contract(s)/Grant(s): WBS 22-708-31-13; Copyright; Avail: CASI; A01, Hardcopy
A polyimide is a polymer composed of alternating units of diamine and dianhydride, linked to each other via an imide
bond. PMR polyimides, commonly used in the aerospace industry, are generally capped at each end by a norbornene endcap
which serves a double function: (1) It limits the number of repeating units and, hence, the average molecular weight of the
various polymer chains (oligomers), thereby improving processibility; (2) Upon further treatment (curing), the endcap
crosslinks the various oligomer strands into a tough heat-resistant piece. Norbornenyl-end capped PMR polyimide resins’ are
widely used as polymer matrix composite materials for aircraft engine applications,2 since they combine ease of processing
with good oxidative stability up to 300 C. PMR resins are prepared by a twestep approach involving the initial formation of
oligomeric pre-polymers capped at both ends by a latent reactive end cap. The end cap undergoes cross-linking during higher
temperature processing, producing the desired low density, high specific strength materials, as shown for PMR-15.
Author
Nuclear Magnetic Resonance; Oxidation Resistance; Polyimides; Oligomers; Degradation; Polymers
20030032382 Florida Univ., Gainesville, FL
Synthesis and In-Situ Atomic Oxygen Erosion Studies of Space-Survivable Hybrid Organic/Inorganic Polyhedral
Oligomeric Silsesquioxane Polymers
Gonzalez, Rene I.; Jan. 2002; 202 pp.; In English; Original contains color illustrations
Contract(s)/Grant(s): AF Proj. 2303
Report No.(s): AD-A410101; AFRL-PR-ED-TP-2002-064; No Copyright; Avail: CASI; A10, Hardcopy
Polymeric materials offer many advantages for low Earth orbit applications including ease of processing and reduced
payload-to-orbit costs derived from a reduction in weight. However, over the last two decades it has been well established that
polymers used in the construction of space vehicles undergo severe degradation resulting in reduced spacecraft lifetimes.
These materials degrade because spacecraft surfaces must endure a high atomic oxygen (AO) flux, bombardment by low and
high-energy charged particles, and thermal cycling along with the full spectrum of solar radiation. Many studies have been
conducted in an effort to determine the mechanism of degradation primarily caused by surface reactions with oxygen atoms.
Unfortunately, these studies have all been carried out after exposing these highly reactive surfaces to air prior to analysis, thus
introducing artifacts that do not represent the true effect of the space environment.
DTIC
Polymers; Surface Reactions; Oxygen Atoms
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