Poly/vinyl ethers/ synthesis for fundamental study of viscoelastic state Final report
Large scale synthesis of amorphous poly/vinyl ethers/ for viscoelastic state study
Anderson, H. A.↗
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Effect of humidity and a wettability additive on polyphenyl ether boundary lubrication of steel in air and nitrogen to 350 C
Determining effect of humidity and wettability additive on boundary lubrication of steel in air and nitrogen with polyphenyl ether
Hady, W. F.↗
Multiple transitions in polyvinyl alkyl ethers at low temperatures
Polyvinyl alkyl ethers multiple transitions at low temperatures, using linear variable differential transformer
Aklonis, J. J.↗
Method of producing alternating ether siloxane copolymers Patent
Method for producing alternating ether-siloxane copolymers with stable properties when exposed to elevated temperatures and UV radiation
Curry, J. E.↗
Hydroxy terminated perfluoro ethers Patent
Chemical synthesis of hydroxy terminated perfluoro ethers as intermediates for highly fluorinated polyurethane resins
Rochow, S. E.↗
Effect of contact angle on rolling-element fatigue life with a fluorinated ether lubricant at a cryogenic temperature of 170 K /305 deg R/
Test of rolling element fatigue life with fluorinated ether lubricant at cryogenic temperature using five ball fatigue tester
Dietrich, M. W.↗
Fluorohydroxy ethers
The preparation of poly(polyfluoroalkylene-glycol) mono (hydroxy polyfluoroalkylene) ethers from fluoroalkylene oxides is described.
Trischler, F. D.↗
Thiophenyl ether disiloxanes and trisiloxanes useful as lubricant fluids
The characteristics of organosilicon compounds for lubrication under extreme conditions are discussed. The substances considered are thiophenyl ether disiloxanes and trisiloxanes. These substances have low pour points and a high degree of radiation resistance. Substitution of sulfur for the phenoxy group oxygen of either siloxane compounds has been found to result in a marked improvement in lubricity. The chemical formulas of the organic compounds are presented.
Bilow, N.↗
Ferrographic analysis of wear debris from boundary lubrication experiments with a five-ring polyphenyl ether
The types of wear particles generated by a five-ring polyphenyl ether in boundary lubrication experiments in various atmospheres were determined by ferrographic analysis. The types of wear particles observed included cylindrical or rocklike organometallic debris, adhesive and cutting wear particles, and some spherical debris. Interpretations as to the mechanism of generation of the various types of particles are presented.
Jones, W. R., Jr.↗
Correlation of elastohydrodynamic film thickness measurements for fluorocarbon type 2 ester, and polyphenyl ether lubricants
A minimum films thickness correlation applicable to heavily loaded elastohydrodynamic (EHD) contacts was formulated from experimental data obtained by an X-ray transmission technique. The correlation, based on data generated with fluorocarbon, type II ester, and polyphenyl ether lubricants, extends a previous analysis developed from data for a synthetic paraffinic oil. The resulting correlation represents the data of the four lubricants reasonably well over a large range of operating conditions. Contained within the derived relation is a factor to account for the high-load dependence displayed by the measurements beyond that which is provided for by the theory. Thermal corrections applied to a commonly used film thickness formula showed little improvement to the general disagreement that exists between theory and test. Choice of contact geometry and material are judged to have a relatively mild influence on the form of the semiempirical model.
Loewenthal, S. H.↗
Effect of viscosity on rolling-element fatigue life at cryogenic temperature with fluorinated ether lubricants
Rolling-element fatigue tests were conducted with 12.7-mm-(1/2-in.-) diameter AISI 52100 steel balls in the NASA five-ball fatigue tester, with a maximum hertz stress of 5500 mN/m2 (800 000 psi), a shaft speed of 4750 rpm, lubricant temperature of 200 K (360 R), a contact angle of 20 deg, using four fluorinated ether lubricants of varying viscosities. No statistically significant differences in rolling-element fatigue life occurred using the four viscosity levels. Elastohydrodynamic calculations indicate that values of the lubricant film parameter were approximately 2 or greater.
Dietrich, M. W.↗
Ferrographic analysis of wear debris from boundary lubrication experiments with a five ring polyphenyl ether
The types of wear particles generated by a five-ring polyphenyl ether in boundary lubrication experiments in various atmospheres were determined by ferrographic analysis. The types of wear particles observed included: cylindrical or rock-like organo-metallic debris, adhesive and cutting wear particles, and some spherical debris. Interpretations as to the mechanism of generation of the various types of particles are presented.
Jones, W. R., Jr.↗
Study of polyphenyl ether fluid /5P4E/ in operating elastohydrodynamic contacts by infrared emission spectroscopy
Infrared emission spectra of 5P4E polyphenyl ether were obtained from an operating elastohydrodynamic sliding contact at different speeds and loads by Fourier emission microspectrophotometry. The spectra were found to be polarized with respect to the direction of the conjunction line, especially at high shear rates. Film and metal surface temperatures were calculated from the spectra, and film thicknesses were determined under various operating conditions. Changes of polarized band structure above a critical shear rate, at which the slope of the film temperature versus shear curve changes abruptly and at which the film thickness assumes a minimum value, are consistent with a transition of the lubricant from a viscous liquid to a viscoelastic liquid or to an elastic solid.
Lauer, J. L.↗
Poly(aryl ethers) and related polysiloxane copolymer molecular coatings: Preparation and radiation degradation
The radiation degradation of poly(arylene ether sulfones) and related materials is studied. These basic studies are important both as a means to developing stronger, more stable matrix resins for composite materials, as well as to improve the data base in regard to chemical structure-physical property relationships. Thirty homo and copolymers were synthesized, at least partially characterized and, in several cases suitable film casting techniques were developed. Four samples were chosen for initial radiation degradation. Poly(dimethyl siloxane) soft bocks/segments can preferentially migrate to the surface of copolymer films. Since siloxanes are utilized as thermal control coatings, this form of 'molecular' coating is of interest. The chemistry for preparing such copolymers with any of the polymers described was demonstrated.
Mcgrath, J. E.↗
Aqueous alkali metal hydroxide insoluble cellulose ether membrane
A membrane that is insoluble in an aqueous alkali metal hydroxide medium is described. The membrane is a resin which is a water-soluble C2-C4 hydroxyalkyl cellulose ether polymer and an insolubilizing agent for controlled water sorption, a dialytic and electrodialytic membrane. It is particularly useful as a separator between electrodes or plates in an alkaline storage battery.
Hoyt, H. E.↗
Polyaryl ethers and related polysiloxane copolymer molecular coatings preparation and radiation degrdation
Poly(arylene ether sulfones) comprise a class of materials known as engineering thermoplastics which have a variety of important applications. These polymers are tough, rigid materials with good mechanical properties over a wide temperature range, and they are processed by conventional methods into products typically having excellent hydrolytic, thermal, oxidative and dimensional stability. Wholly aromatic random copolymers of hydroquinone and biphenol with 4.4 prime dichlorodiphenyl sulfone were synthesized via mechanical nucleophilic displacement. Their structures were characterized and mechanical behavior studied. These tough, ductile copolymers show excellent radiation resistance to electron beam treatment and retain much of the mechanical properties up to at least 700 Mrads under argon.
Mcgrath, J. E.↗
Modification of epoxy-reinforced glass-cloth composites with a perfluorinated alkyl ether elastomer
A perfluorinated alkyl ether diacyl fluoride prepolymer (molecular weight about 1500) was coreacted with Epon 828 epoxy resin and diamino diphenyl sulfone to obtain an elastomer-toughened, glass-cloth composite. Improvements in flexural toughness, impact resistance, and water resistance, without loss of strength, modulus of elasticity or a lowering of the glass-transition temperature, were realized over those of the unmodified composite. Factors concerning optimization of the process are discussed. Results suggest that a simultaneously interpenetrating polymer network may be formed which gives rise to a measured improvement in composite mechanical properties.
Rosser, R. W.↗
Morphology and Dynamic Mechanical Properties of Diglycidyl Ether of Bisphenol-A Toughened with Carboxyl-Terminated Butadiene-Acrylonitrile
The fracture toughness of an incorporation of a carboxyl-terminated butadiene acrylonitrile (CTBN) elastomer in diglycidyl ether bisphenol A (DGEBA) resin was investigated. Measurements of dynamic mechanical properties, scanning electron microscopy and small-angle X-ray scattering were carried out to characterize the state of cure, morphology and particle size and size distribution of the neat resins and their graphite fiber reinforced composites.
Hong, S. D.↗