... at: www.astm.org David Hirsch1 and Harold Beeson2 Some Issues Related to the Selection of Polymers for Aerospace Oxygen Systems ABSTRACT: Materials intended for use in aerospace oxygen systems are commonly screened for oxygen compatibility following NASA STD 6001. This standard allows quali cation of materials...

...F Baldi; D Rösch In the past some studies have been carried out to investigate the melt strength of polymers with the purpose of comparing the results obtained with different materials and at different temperatures. In those experimental activities, once that the testing instrument had been chosen...

...SL Schaeffer; RL Johnson; WB Lewis This study was conducted to compare the Izod impact values of injection molded polymer specimens with molded- versus machined-notch specimens. The ASTM D 256 notched Izod impact test was used to measure the impact values of both specimen types. The impact values...

...RF Karg Studies of the rheological behavior upon milling and compounding of styrene-butadiene rubber (SBR) polymers having different molecular weight and molecular weight distribution using the Monsanto processibility tester show that polymers having a high molecular weight fraction have higher...

... of the copolymer. It was determined that mechanical drying added to the “shear history” of the polymer and contributed to premature breakdown. Furthermore, the rheological properties of the polymer are altered in a manner that suggests the presence of long-chain branching. These alterations persist...

... the advantages of greater signal-to-noise ratio and digitized data that open up new areas of application as well as provide greater sensitivity in the more traditional uses of IR spectroscopy. A review of the field of vibrational spectroscopy of polymers identifies time-dependent phenomena and characterization...

...B Ashar; LR Turcotte The intrinsic viscosity of polymer solutions is widely used for characterizing the molecular sizes of polymers. The experimental procedure is very involved, and therefore a variety of precautions needs to be observed to eliminate errors. In this paper, a hypothetical case...

...YW Mai The use of surface-crack specimens subjected to tension and bending loads for the fracture toughness evaluation of two typical polymers, polypropylene and polystyrene, is described. Experimental results are discussed with particular reference to various correction factors such as slow growth...

...CWR Wade; AF Hegyeli; RK Kulkarni The bioabsorbable polymers poly(DL-lactic acid), poly-(isobutyl 2-cyanoacrylate), and poly(methyl 2-cyanoacrylate) have been evaluated comparatively in organ and cell cultures in vitro and in rat muscle tissues in vivo. Effects of the polymers on cell ultra...

...CG Seefried, Jr; JV Koleske The determination and analysis of dynamic mechanical properties provide valuable information to characterize polymeric materials. Such testing of polymers with a torsional pendulum is a relatively simple procedure which requires a small amount of sample and is especially...

...GM Idorn Session III-9 of the VI International Congress of the Chemistry of Cement (held in September 1974 in Moscow) dealt with cement-polymer materials, or, as it appears from the papers presented, with various types of composites using ordinary cements and organic monomers together as binding...

...RE Evans A modification of a friction and wear test apparatus is described which permits measurement of the coefficient of friction (COF) of polymer pellets at conditions comparable to those in the solids feed section of an extruder. A specimen holder containing three pellet-filled cylinders...

... water/cement ratio lie mainly in the region of large pores. KEY WORDS: porosity, capillarity, cements(adhesives), hydraulic cements, porosimeters, measurement, hydration, water of hydration, polymers volume generally considered to lie between gel pores and capillary pores. From this evidence Winslow...