Abstract: Drawing, especially cold-drawing, or hot-drawing or other heat-treatments of spin-oriented crystalline polyester filaments, and particularly polyester feed yarns, that have been prepared by spinning at speeds of, e.g., 4 kg/min, and have low shrinkage and no natural draw ratio in the conventional sense, provides useful technique for obtaining uniform drawn filaments of desired denier and thereby provides improved flexibility to obtain filaments and yarns of various denier. The resulting uniform filaments have useful properties that are improved in certain respects.
Abstract: An improved aqueous electrocoating composition that contains a reactive additive of the following formula ##STR1## wherein R is an aliphatic hydrocarbon group; finishes formed from the composition have improved cure and chip resistance.
Type:
Grant
Filed:
April 10, 1991
Date of Patent:
November 19, 1991
Assignee:
E. I. Du Pont de Nemours and Company
Inventors:
Ding Y. Chung, Tapan K. Debroy, Sioe-Heng A. Tjoe
Abstract: A new method of forming composites or laminates into complex shapes has been developed. A process using a die with piercing studs allows control of fibers motion during processing, leading to better composite parts.
Type:
Grant
Filed:
September 6, 1990
Date of Patent:
November 19, 1991
Assignees:
Massachusetts Institute of Technology, E. I. Du Pont de Nemours & Co.
Inventors:
Timothy G. Gutowski, Michael F. Sentovich, Richard K. Okine
Abstract: A filter connector comprising a filter unit and a metal frame for releasably mounting said filter connector to the metal chassis of electrical apparatus. The mounting frame is formed of electrically conducting material, comprising a flat base plate with feed-through apertures for the contact elements and is provided with resilient mounting lips which project relative to said base plate for latchably mounting the filter connector in a self-latching manner on a chassis.
Abstract: A high solids coating composition useful as a clear coat for an automotive clear coat/color coat finish which contains about 40-80% by weight of a binder and correspondingly about 20-60% by of a liquid organic carrier; wherein the binder contains about:a. an acrylic solution polymer of polymerized monomers of ethylenically unsaturated esters of acrylic acid or methacrylic acid and a hydroxy alkyl acrylate or methacrylate and the polymer has a hydroxyl no. of about 50-200 and a weight average molecular weight of about 4,000-20,000;b. a dispersed polymer of polymerized monomers having stabilizer resin segment that is soluble in the organic carrier and dispersed resin segment that is relatively insoluble in the organic carrier;c. a siloxane oligomer having --OH and --OR groups attached to the silane atoms of the oligomer where R is an alkyl group having 1-6 carbon atoms in the alkyl group or an aryl group and the oligomer has a weight average molecular weight of about 500-5,000; andd.
Abstract: Azeotropic mixtures of 3-chloro-1,1,1-trifluoropropane (HCFC-253fb) with trans-1,2-dichloroethylene (t-HCC-1130) are useful in solvent cleaning applications.
Abstract: An apparatus for loading and unloading open top railroad cars (46) utilizing a conventional material handling equipment item attached to a slidable structure (20). The material handling equipment item is equipped with a boom structure (64) and material handling device (66). During railcar loading and unloading operations, the operator positions and attaches the material handling equipment item onto the slidable structure (20) which is positioned adjacent to an end of the railcar (46). The front of the structure is engaged with the top surface of the railcar endwall (72) and the material handling device is positioned on the railroad bed (52) adjacent to the rear of the slidable structure (20). The boom structure (64) is then extended to position the apparatus atop the railcar (46). The apparatus (18) is then supported on the sidewall (76) upper surface of the railcar by support members (22) which are hydraulically extendable from the structure ends (36).
Abstract: A waterproof hydrophilic copolyetherester film having a high water vapor transmission rate can be secured surprisingly well to polyester fiberfill batting, so provides advantages in processing, and provides improved comfort to the wearer when the composite is used in apparel.
Type:
Grant
Filed:
November 14, 1990
Date of Patent:
November 12, 1991
Assignee:
E. I. Du Pont de Nemours and Company
Inventors:
Michael S. Frankosky, George J. Ostapchenko
Abstract: A process for separating and recovering organic vapors (e.g., chlorofluorocarbons) from a feed stream of organic vapors and air wherein organic vapors are present in the "window concentration" range being too high for conventional carbon adsorption and too low for efficient compression/condensation recovery. By passing the organic vapor and air feed stream through the feed side of a semipermeable membrane unit, a vapor depleted stream exiting the membrane unit can then be processed by conventional carbon adsorption while a vapor enriched stream from the membrane unit can be processed by conventional compression and condensation.
Abstract: Improved pawl assembly for starting mechanisms of small engines mounted on the engine flywheel provided with a bore therein and includes an integrally molded, polymeric pawl, a U-shaped torsion spring and retaining means disposed in the bore of the flywheel. The pawl has a depending shank rotatably fitted into the bore of the flywheel and oppositely extending end portions. The outer end portion, or spur, is adapted to engage a fin or vane of the flywheel to orient the inner end portion, or toe, of the pawl to engage the teeth of the ratchet surface of a pulley type starter. The closed end of the torsion spring is fitted over the shank and urges the pawl to its ratchet engaging position. The spring includes leg portions fitted into the bore of the flywheel and each leg terminates in a laterally extending hook portion adpated to interfit within the retaining means disposed at the end of the bore opposite the end into which the shank is fitted.
Abstract: The molecular weights (Mw and Mn) and polydispersity (Mw/Mn) of a polymer have significant impact on the final product properties and processability of materials made out of it. This invention provides a method for on-line prediction of polymer properties. In a continuous polymerization reactor in which an irreversible polymerization reaction occurs, sensors provide axial temperature and pressure profile in the reactor as well as monomer flow rates and concentration for determining Mw, Mn and polydispersity. Based on a non-Newtonian fluid mechanics analysis, differential influx analysis of a side stream incorporation and determination of the moments of the molecular weight distribution via a Newton-Raphson algorithm, the model calculates an axial polymer properties profile.On-line real time "analytical measurement" of polymer properties is used to alert the operator of unusual reactor problems, to optimize reactor operation during shut-down and start-up or rate changes.
Abstract: Azeotropic mixtures of 1,1,1,2,3,4,4,5,5,5-decafluoropentane and methanol or ethanol or isopropanol, the azeotropic mixtures being useful in solvent cleaning applications, as blowing agents, refrigerants, heating mediums and aerosol propellants.
Abstract: Extruded shaped structures of amorphous polyarylate copolymers, having a tensile elongation at break of at least 80% at 25.degree. C., are made by drawing a molten extrudate of the copolymer at a temperature at least 100.degree. C. above the glass transition temperature of the copolymer.
Abstract: A portable device allowing the rapid aiding of individuals suffering from difficulty in breathing, movement and communication, in a situation of environmental risk in the form of toxic and contaminating agents, said device comprising a wrapping of flexible material impermeable to gas, vapor, fumes, aerosol and dusts, a window in said wrapping, hermetically closed by a flexible transparent material for the visualization of the inside thereof, a box-shaped body in fluid communication with an extremity of said wrapping and carrying a system for the filtering, feeding and pressurization of the air, and at least one exhaust valve of the air in said wrapping.
Type:
Grant
Filed:
September 7, 1990
Date of Patent:
November 12, 1991
Assignees:
Comitato Nazionale per la Ricerca e per lo Sviluppo dell'Energia Nucleare e delle Energie Alternative, Grenfil S.r.l.
Abstract: A process for preparing X-ray intensifying M' monoclinic tantalate phosphors by firing precursor oxides in a novel flux mixture containing a compound capable of producing an alkali metal oxide and an effective amount of an alkali metal metasilicate. Tantalate phosphors made in this manner have improved efficiency and purity. X-ray intensifying screens made from these phosphors have improved speed and can be used with good results with a plurality of X-ray film elements.
Abstract: Economic and efficient process for preparing an oligomer of poly(butylene terephthalate) or an oligomer of poly(butylene isophthalate) from a transesterification reaction mass by using a countercurrent column reactor system wherein the transesterification reaction mass is fed into the countercurrent column reactor and continuously flows downward while simultaneously a heated inert gas stream continuously flows upward to scrub out volatiles from the transesterification reaction mass, thereby yielding from the bottom of the countercurrent column reactor an oligomer of poly(butylene terephthalate) or an oligomer of poly(butylene isophthalate) suitable for use in a polycondensation reaction. Butanediol is recycled throughout the process through an absorber column.
Type:
Grant
Filed:
August 1, 1990
Date of Patent:
November 12, 1991
Assignee:
E. I. duPont de Nemours and Company
Inventors:
Roy Jackson, David J. Lowe, Clare A. Stewart
Abstract: Xeroprinting process comprising(A) exposing imagewise to actinic radiation a photohardenable electrostatic master comprising(1) an electrically conductive substrate, and(2) a layer of photohardenable composition consisting essentially of(a) at least two organic polymeric binders, at least one having a Tg greater than 80.degree. C. and at least one having a Tg less than 70.degree. C.,(b) at least one monomeric compound having at least one ethylenically unsaturated group, and(c) a photoinitiator or photoinitiator system, the shift in transit time (a.sub.T) of the photohardenable layer in the range of 30%.ltoreq.relative humidity.ltoreq.60% and 15.6.degree. C..ltoreq.temperature .ltoreq.26.7.degree. C. is 15 or less, preferably 10 or less(B) charging the photohardenable master electrostatically,(C) applying an oppositely charged electrostatic toner, and(D) transferring the toned image to a receptor surface.
Type:
Grant
Filed:
December 3, 1990
Date of Patent:
November 12, 1991
Assignee:
E. I. Du Pont de Nemours and Company
Inventors:
Graciela B. Blanchet-Fincher, Catherine T. Chang, Curtis R. Fincher, Jr.
Abstract: The user of a new pager places it into "registration mode" by commands entered through the pager's user interface. In registration mode, the pager displays previously stored identification code and begins rapidly searching through a list of candidate paging channels. The user then telephones the paging system clearinghouse and provides the identification code. Upon receiving this information, the paging system broadcasts an initialization message addressed to the new pager. Included in the message may be initialization data, such as a list of alternative frequencies on which the paging data may be found. The pager quickly receives this message (due to its rapid searching operation) and stores any initialization data in data registers for future reference. The pager then displays a message to the user confirming the pager's proper operation.
Abstract: Improved process for extruding through a die a difficultly-melt-processible polymer, especially a polymer containing an additive such as an antiblock agent. There is first extruded through the die a polymer resin containing 0.001 to 1 wt. % of a copolymer of tetrafluoroethylene and a functional-group-containing monomer that is terminated in a -CF.sub.2 W group wherein W is selected from -SO.sub.2 F, -SO.sub.2 Cl, -SO.sub.3 M, -COOR and -COOM, R is a C.sub.1-3 alkyl radical and M is H, a metal cation or an ammonium or quaternary ammonium cation, and thereafter there is extruded through the die the difficultly-melt-processible polymer admixed with 0.001-1 wt. % of a fluoropolymer process said having a fluorine to carbon ratio of at least 1:2.
Abstract: Blends of a major portion of ethylene vinyl alcohol copolymer (EVOH) and a minor portion of an amorphous polyamide and preferably also a semicrystalline nylon are disclosed. These blends may be formed into films or multilayer structures, which can be thermoformed into containers or other articles. The presence of the minor portion of amorphous polyamide permits thermoforming of the EVOH at lower temperatures without the formation of defects.