Abstract Qualitative and quantitative studies with model compounds have shown that a variety of reactions may occur at 100–300° in molecules containing isocyanate, urea urethane groups. All or most these are subject to catalysis so they be induced proceed lower temperatures. These quite important as affect the production practical use polyurethanes polyureas. By proper selection reaction components one design polyurethane polyurea molecule which will give both reasonable rate cure final...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhosgene Derivatives. The Preparation of Isocyanates, Carbamyl Chlorides and Cyanuric Acid1R. J. Slocombe, Edgar E. Hardy, H. Saunders, R. L. JenkinsCite this: Am. Chem. Soc. 1950, 72, 5, 1888–1891Publication Date (Print):May 1, 1950Publication History Published online1 May 2002Published inissue 1 1950https://pubs.acs.org/doi/10.1021/ja01161a009https://doi.org/10.1021/ja01161a009research-articleACS PublicationsRequest reuse permissionsArticle...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Preparation and Polymerization of Some Substituted Styrenes1,2C. S. Marvel, C. G. Overberger, R. E. Allen, J. H. SaundersCite this: Am. Chem. Soc. 1946, 68, 5, 736–738Publication Date (Print):May 1, 1946Publication History Published online1 May 2002Published inissue 1 1946https://pubs.acs.org/doi/10.1021/ja01209a004https://doi.org/10.1021/ja01209a004research-articleACS PublicationsRequest reuse permissionsArticle...

Abstract Sufficient data are available from studies of urethan foams and elastomers to draw semiquantitative conclusions regarding the effect any gross structural change on most polymer properties. These relationships apply other areas application as well, e.g., coatings, adhesives sealants. Future research may be expected provide more reliable control many reactions involved in preparing urethans, thus better over structure. Similarly a quantitative extensive knowledge properties expected....

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDevelopment of Cast Urethane Elastomers for Ultimate Properties.K. A. Pigott, B. F. Frye, K. R. Allen, S. Steingiser, W. C. Darr, J. H. Saunders, and E. HardyCite this: Chem. Eng. Data 1960, 5, 3, 391–395Publication Date (Print):July 1, 1960Publication History Published online1 May 2002Published inissue 1 July 1960https://pubs.acs.org/doi/10.1021/je60007a044https://doi.org/10.1021/je60007a044research-articleACS PublicationsRequest reuse...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Preparation of 2-Alkylbutadienes1C. S. Marvel, R. L. Myers, and J. H. SaundersCite this: Am. Chem. Soc. 1948, 70, 5, 1694–1699Publication Date (Print):May 1, 1948Publication History Published online1 May 2002Published inissue 1 1948https://pubs.acs.org/doi/10.1021/ja01185a006https://doi.org/10.1021/ja01185a006research-articleACS PublicationsRequest reuse permissionsArticle Views875Altmetric-Citations40LEARN ABOUT THESE METRICSArticle Views are...

Abstract The thermal responses of various polyurethane elastomers in the form changes heat capacity, linear expansion, and tensile strain have been examined. Most change which can be attributed to backbone polyethylene adipate, found several modes analysis, are still apparent, though shifted somewhat, among most diisocyanate extended used this study. Tolylene extension modulus properties markedly, low being observed at ambient temperatures. Both hydrogenated MDI show comparable expansion...

Abstract Polyurethans are well suited to the design of polymers for good ablation and flame-resistance. Best results in flame resistance may be expected when a composite structure is formed from an inorganic component self-extinguishing organic binder. The should present large amounts so that space between particles small. For low overall density material preferably foamed. binder designed give minimum spread, heat combustion smoke generation. authors believe best practical will achieved if...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Preparation and Polymerization of Four Isomeric Dimethylstyrenes1,2C. S. Marvel, J. H. Saunders, C. G. OverbergerCite this: Am. Chem. Soc. 1946, 68, 6, 1085–1088Publication Date (Print):June 1, 1946Publication History Published online1 May 2002Published inissue 1 June 1946https://pubs.acs.org/doi/10.1021/ja01210a050https://doi.org/10.1021/ja01210a050research-articleACS PublicationsRequest reuse permissionsArticle...

We present an inversion method for 3D electrical imaging in media with inhomogeneous and anisotropic conductivity distribution. The distribution is discretized via finite elements described by a second-order tensor at each element node. formulated as functional optimization error containing terms measuring data misfit model covariance means of smoothness, anisotropy deviation from starting model. Including the information overcomes problem ill-posedness expense limiting allowed models to...

Investigation of the thermal degradation rigid urethane foams by means TGA, DTA, infrared, and other techniques indicated that prepared from a polyoxypropyl ene ether polymeric diphenylmethane type polyisocyanate began to decompose at ap proximately 210°C. Loss weight occurred in two stages approximately 50% each, oc curring 250-350°C 400- 600°C. A similar pattern decomposition was found for based on chlorinated polyester same polyiso cyanate. Addition reactive organophos phorous flame...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Preparation of Isocyanates by the Thermal Decomposition Substituted Ureas1William B. Bennet, J. H. Saunders, and Edgar E. HardyCite this: Am. Chem. Soc. 1953, 75, 9, 2101–2103Publication Date (Print):May 1, 1953Publication History Published online1 May 2002Published inissue 1 1953https://doi.org/10.1021/ja01105a024RIGHTS & PERMISSIONSArticle Views570Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are COUNTER-compliant sum full text...

We present results from a new numerical model capable of simulating two‐phase flow in porous medium and the electrical potentials arising due to electrokinetic phenomena. suggest that, during water‐flood an initially oil‐filled reservoir, encroaching water causes changes potential at production well which could be resolved above background noise; indeed, approaching detected several 10's 100's meters away. The magnitude measured depends upon rate, coupling between fluid potentials, nature...

Abstract We present a surface-based approach to reservoir model construction in which all geological heterogeneity, whether structural, stratigraphic, sedimentological or diagenetic, that impacts on the spatial distribution of petrophysical properties is modelled as one more discrete volumes bounded by surfaces. The surfaces can be deterministically interpolated between control lines points, incorporate stochastic element where data are sparse. Models constructed from not constrained an...

Abstract An understanding of the formation urethan foams involves consideration organic chemistry reactions leading to gas and molecular growth, colloid nucleation phenomena bubble stability, rheology polymer system as it cures. Experimental data are not available permit complete evaluation all details foam cure. Nevertheless enough information has been developed in related fields one develop a fairly reasonable explanation process. This summary attempts present such picture, is concerned...

In this paper, a numerical method for solving the Biot poroelastic equations is developed. These comprise acoustic (typically water) and elastic (porous medium frame) equations, which are coupled mainly through fluid/solid drag terms. This wave solution to simplified form of Maxwell's solved streaming potential resulting from electrokinesis. The ultimate aim use generated electrical signals provide porosity, permeability other information about formation surrounding borehole. electrokinesis...

Abstract A series of model polyurethanes and polyureas, a polyamide, polyimide were prepared by reacting 4,4′‐diphenylmethane diisocyanate or polyisocyanates having similar polybenzyl structures with aliphatic aromatic coreactants. Thermogravimetric analyses indicated that the flammability polymers was related to formation volatile flammable products during early stages decomposition. Determinations heat evolved differential thermal thermodynamic heats combustion suggested extent rate...

Summary Spontaneous potential (SP) is routinely measured using wireline tools during reservoir characterization. However, SP signals are also generated hydrocarbon production, in response to gradients the water-phase pressure (relative hydrostatic), chemical composition, and temperature. We use numerical modeling investigate likely magnitude of an oil suggest that measurements SP, electrodes permanently installed downhole, could be used detect monitor water encroaching on a well while it...

Abstract The development of new and more sensitive techniques in thermal analyses aids a complete understanding the contributions individual components urethane elastomers regarding their mechanical thermodynamic behavior. behavior various segments reported this work illustrates clearer interpretation reasons for changes caused by heat capacity, volume tensile properties; gross previously polyurethane properties as function temperature are also confirmed with exact definition origin....

We have examined the behavior of streaming potential under multiphase conditions, and conditions varying temperature salinity, to evaluate feasibility using downhole streaming-potential measurements determine fluid distributions in a reservoir. Using new insights into pore-scale distribution fluids electric charge, we found that saturation dependence coupling coefficient is important determining resulting potential. Through examination four independent physical parameters which comprise...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of Acids and Bases on Preparation Urethane PolymersH. L. Heiss, F. P. Combs, G. Gemeinhardt, J. H. Saunders, E. HardyCite this: Ind. Eng. Chem. 1959, 51, 8, 929–934Publication Date (Print):August 1, 1959Publication History Published online1 May 2002Published inissue 1 August 1959https://pubs.acs.org/doi/10.1021/ie50596a034https://doi.org/10.1021/ie50596a034research-articleACS PublicationsRequest reuse permissionsArticle...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPreparation of Polymers from Diisocyanates and PolyolsH. L. Heiss, J. H. Saunders, Marjorie E. Morris, B. R. Davis, Edgar HardyCite this: Ind. Eng. Chem. 1954, 46, 7, 1498–1503Publication Date (Print):July 1, 1954Publication History Published online1 May 2002Published inissue 1 July 1954https://doi.org/10.1021/ie50535a052RIGHTS & PERMISSIONSArticle Views191Altmetric-Citations15LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Preparation and Polymerization of the Six Nuclear Isomeric Dichlorostyrenes1,2C. S. Marvel, C. G. Overberger, R. E. Allen, H. W. Johnston, J. Saunders, D. YoungCite this: Am. Chem. Soc. 1946, 68, 5, 861–864Publication Date (Print):May 1, 1946Publication History Published online1 May 2002Published inissue 1 1946https://pubs.acs.org/doi/10.1021/ja01209a045https://doi.org/10.1021/ja01209a045research-articleACS PublicationsRequest reuse...