Abstract: Substantially homogeneous aqueous suspensions of low density microspheres are presented as contrast media for imaging the gastrointestinal tract and other body cavities using computed tomography. In one embodiment, the low density microspheres are gas-filled. With computed tomography, the contrast media serve to change the relative density of certain areas within the gastrointestinal tract and other body cavities, and improve the overall diagnostic efficacy of this imaging method.

Abstract: Disclosed are a polymer gel in which a phase transition occurs due to a stimulus, a method of manufacturing such a polymer gel, and an actuator which employs such a polymer gel. The polymer gel which is formed by polymerizing monomers at a temperature equal to or less than a phase transition temperature of the resultant polymer gel and separating and/or classifying the polymer gel into fractions according to its size at a temperature equal to or greater than the phase transition temperature thereof. Alternatively, the polymer gel is separated and/or classified into fractions by adding a low molecular weight compound that can dissolve and swell the polymer gel to separate the polymer gel into fractions based upon a difference in dissolving rate or swelling rate. Alternatively separation and/or classification of the polymer gel is performed by a combination of the above-described two methods. In consequence, the resultant polymer gel has an average particle size ranging from 0.1 .mu.m to 100 .mu.

Abstract: A method for altering a macroporous cross-linked hydrophobic copolymeric lattice produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymeric lattice hydrophilic. The method involves saponifying the hydrophobic copolymeric lattice by reacting the surface of the hydrophobic copolymeric lattice with an aqueous alkali. The surface can also be rendered hydrophilic by polymerizing an acrylate monomer onto the lattice in order to form a surface containing carboxylic acid sites. The carboxylic acid sites formed on the surface of the lattice are converted to carboxylate anions.

Abstract: This invention relates to a novel, environmentally acceptable blowing agent and blowing agent blends and a process for producing thermalplastic, and particularly polyolefin foams using the environmentally acceptable blowing agent(s). The blowing agents of the present invention comprise difluoromethane and optionally a second blowing agent component which is nonflammable and possesses good blowing agent properties. Polyolefin foam is made by mixing a polyolefin resin and the blowing agent and introducing the resin/blowing agent mixture into a zone of lower pressure.

Abstract: A method of making a foamed polymer article by injection molding, using a foaming agent that does not form byproducts which could pit or chalk the polymer surface. The foaming agent contains sodium borohydride in an amount from 0.01 to 5.0 weight percent of the polymer, and sodium dihydrogen phosphate as an activator to react with the sodium borohydride and produce hydrogen gas. The sodium borohydride and the sodium dihydrogen phosphate are kept separated from direct contact with each other, such as by encapsulating the components, until gas production is desired when the polymer is heated.

Abstract: Uniformly sized polymer particles of 1-50 .mu.m diameter are made by gradually combining a water-insoluble monomer mixture with an aqueous dispersion of emulsion-polymerized polymer particles in the presence of a dispersion stabilizer and an oil-soluble, free-radical polymerization initiator.

Abstract: A foamable polymer composition comprising[A] at least one cyclo-olefin resin selected from the group consisting of(A-1) ring-opened polymers derived from cyclo-olefins represented by the following general formula [I],(A-2) ring-opened copolymers derived from the cyclo-olefins of general formula [I],(A-3) hydrogenation products of the ring-opened polymers (A-1),(A-4) hydrogenation products of the ring-opened copolyers (A-2), and(A-5) addition polymers of the cycloolefins of general formula [I] with ethylene, and[B] a blowing agent, ##STR1## wherein n is 0 or a positive integer; R.sup.1 to R.sup.12, independently from each other, represent an atom or a group selected from the class consisting of a hydrogen atom, halogen atoms and hydrocarbon groups; R.sup.9 to R.sup.12 may be linked to each other to form a monocyclic or polycyclic hydrocarbon group; and R.sup.9 and R.sup.10, or R.sup.11 and R.sup.12 may each form an alkylidene group.

Abstract: A method for making low density (0.8-1.1 lb./cu.ft.) expanded polymeric products uses blowing agent in an amount of any from 2 to 4.4 weight percent and aging periods of from 1 to 80 hours after each expansion step. The process uses 2 to 5 expansion steps and a polymer having a particular polydispersity, weight average molecular weight and M.sub.z :M.sub.n, this polymer having a greater expandability than conventional polymers. The process requires only about half of the amount of blowing currently being used in commercially viable processes for making expanded polystyrene products. The process can be used with or without a molding step.

Abstract: A polystyrene polymer as well as an expandable polystyrene formulation comprises a polystyrene polymer having a particular molecular weight distribution. The polymer itself exhibits a polydispersity of from about 1 to less tha 2.0, a weight average molecular weight of greater than about 200,000 to about 300,000, and an M.sub.z :M.sub.n of from about 2 to less than about 3.0. Furthermore, the polystyrene polymer is branched to from 0 to less than 5 weight percent.The expandable polystyrene formulation comprises a polystyrene polymer exhibiting a polydispersity of from about 1.0 to less than 2.5, a weight average molecular weight of from greater than about 180,000 to about 300,000, an M.sub.z :M.sub.n of from about 2 to about 4.5. The polystyrene polymer is present in an amount of from about 94.5 weight percent to about 98 weight percent, based on the total weight of the formulation, and the polystyrene polymer is branched to from 0 to less than 5 weight percent.

Abstract: A method for making low density (0.8-1.1 lb/cu.ft.) expanded polymeric products uses blowing agent in an amount of only from 2 to 4.4 weight percent and aging periods of from 1 to 80 hours after each expansion step. The process uses 2 to 5 expansion steps and a polymer having a particular polydispersity, weight average molecular weight and M.sub.z :M.sub.n, this polymer having a greater expandability than conventional polymers. The process requires only about half of the amount of blowing agent currently being used in commerically viable processes for making expanded polystyrene products. The process can be used with or without a molding step.

Abstract: A method for making low density (0.8-1.1 lb/cu. ft.) expanded polymeric products uses blowing agent in an amount of only from 2 to 4.4 weight percent. The process uses 2 to 5 expansion steps together with a polymer having a particular polydispersity, weight average molecular weight and M.sub.z :M.sub.n, this polymer having a greater expandability than conventional polymers. The process requires only about half of the amount of blowing agent currently being used in commercially viable processes for making expanded polystyrene products. The process can be used with or without a molding step.

Abstract: A method for making low density (0.8-1.1 lb/cu.ft.) expanded polymeric products uses blowing agent in an amount of only from 2 to 4.4 weight percent. The process uses 2 to 5 expansion steps together with a polymer having a particular polydispersity, weight average molecular weight and M.sub.z :M.sub.n, this polymer having a greater expandability than conventional polymers. The process requires only about half of the amount of blowing agent currently being used in commercially viable processes for making expanded polystyrene products. The process can be used with or without a molding step.

Abstract: Absorbent polymeric macrostructures that are porous and comprise an interparticle crosslinked aggregate having a circumscribed dry volume greater than about 10.0 mm.sup.3. The interparticle crosslinked aggregate comprises a multiplicity of precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material; and an interparticle crosslinking agent reacted with the polymer material of the precursor particles to form crosslink bonds between the precursor particles. Because of the particulate nature of the precursor particles, the macrostructure has pores between adjacent precursor particles. The pores are interconnected by intercommunicating channels such that the macrostructure is liquid permeable.

Abstract: The cross-linkable, foamable polyolefin resin composition capable of forming foams with excellent mechanical properties and heat resistance is made of (a) 30-80 weight % of a propylene-ethylene random copolymer having an ethylene content of 1.5-6 weight %; (b) 10-60 weight % of a propylene-ethylene random copolymer having an ethylene content of 0.2-1.0 weight %; (c) 10-60 weight % of a linear low-density polyethylene; and (d) 1-30 parts by weight, per 100 parts by weight of the above resin components, of a foaming agent.

Abstract: Olefin polymer foams prepared utilizing "soft" blowing agents have improved properties when a small amount of a stability control agent comprising a glycerol monoester of a C.sub.20-24 fatty acid is employed.

Abstract: A method for making low density (0.8-2 lb/cu.ft.) expanded polymeric products uses blowing agent in an amount of only from 2 to 4.4 weight percent, the process emitting blowing agent during processing in an amount of from only about 0.3 to about 2.5 weight percent. The process uses 2 to 5 expansion steps together with a polymer having a particular polydispersity, weight average molecular weight and M.sub.z :M.sub.n, this polymer having a greater expandability than conventional polymers. The process requires only about half of the amount of blowing agent currently being used in commerically viable processes for making expanded polystyrene products. The process can be used with or without a molding step.

Abstract: An electrically conductive flexible polyurethane foam having fine and homogeneous cells, being low in swelling by water and superior in dimensional stability can be prepared by mixing an isocyanate terminated urethane prepolymer holding isocyanate monomers therein prepared by reacting polyether polyol(s) holding poly(oxypropylene) chains and not more than 30 weight % of poly(oxyethylene) chains therein with a stoichiometrically excessive amount of an isocyanate component with an aqueous dispersion of electrically conductive carbon particles containing water in excess of the stoichiometric amount necessary to react with the isocyanate monomers in the urethane prepolymer and foaming the mixture in a closed mold having a capacity smaller than the volume of a foam which can be obtained by conducting the foaming of the said mixture of the urethane prepolymer and the aqueous dispersion of electrically conductive carbon particles freely under atmospheric pressure.

Abstract: Disclosed is a semiconductive rubber foam having a volume resistivity that can be controlled to a practical level and retaining an initial softness (hardness) even after the lapse of time. This semiconductor rubber foam is composed of a molded article obtained by curing and foaming a rubber composition comprising (A) 100 parts by weight of a chlorinated ethylene/.alpha.-olefin copolymer rubber and (B) 10 to 50 parts by weight of carbon black. The volume resistivity of this semiconductive rubber foam has is in the range of from 10.sup.5 to 10.sup.11 .OMEGA.-cm.

Abstract: A molded polypropylene foam tire core suitable for all types of wheels. The core may be inserted, in one or more sections, into a pneumatic-type tire casing and mounted on a wheel rim to provide puncture-proof and rupture-proof internal support for said tire casing.

Abstract: In accordance with the present invention, there is provided a bubble-containing ehtylene/.alpha.-olefin rubber excellent in kneadability, characterized in that the ethylene/.alpha.-olefin rubber prepared by copolymerization of 50-95 mol% of ethylene, 5-50 mol% of .alpha.-olefin having at least 3 carbon atoms and 0-10 mol% of non-conjugated polyene contains 5-1000 parts by volume, based on 100 parts by volume of said rubber, of bubbles and has a water absorption volume as measured in accordance with ASTM D 1506 of less than 20% by volume of the total bubble volume.

Abstract: Water insoluble polymers are treated to place on their exposed surfaces the pendant alkyl imidocarbonyl (amide) groups to impart a high degree of hydrophilicity to that surface. Nitrile-containing polymers or copolymers in the form of insoluble films, filters or membranes are treated to convert a substantial fraction of the surface nitrile groups into the corresponding amide by the use of hydrogen peroxide or concentrated acids. The surface is rendered hydrophilic and resistant to fouling to the extent that even proteins are not denatured thereupon. The surface may also be converted to substituted amides by subsequent reactions to impart to it other functionalities or to serve as the basis for coupling reactions. Other polymers capable of surface treatment to produce pendant amidocarbonyl groups include ones containing pendant esters which on cleavage of the oxygen-carbon bond give pendant alcohol groups.

Abstract: Isotropic porous polymer beads having a high surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of an acrylonitrile polymer or a copolymer by a thermally-induced phase separation process. The use of mixed solvent-non-solvent combinations as solvents for the polymers, produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.

Abstract: Foam particles of propylene polymers which have shrunk from 40 to 95% of their original volume and have a bulk density of from 10 to 30 g/1 can be expanded if they are treated with air or nitrogen under superatmospheric pressure, subsequently decompressed. If desired post-foamed by heating and, after aging, re-treated with air or nitrogen under superatmospheric pressure, subsequently decompressed and aged under atmospheric pressure until the pressure in the cells has dissipated.

Abstract: A soft, flexible, microporous film is provided having high tensile strength and good air and water vapor transmission rates therethrough while being substantially impenetrable to liquid water. This film is prepared by stretching a casting of a composition of a polyolefin and high levels of CaCO.sub.3 or glass beads and calcium stearate in two directions from 1.5-7 times in each direction to produce a film having a Gurley porosity of from 0.1 to 85 seconds. This film is especially useful for disposable items such as feminine panty liners, diapers, bed sheets, and hospital gowns. When glass beads are substituted for the CaCO.sub.3, the film is useful for battery separators.

Abstract: It is an object of the present invention to provide a volatile foaming agent composition for thermoplastic resins capable of producing a thermoplastic resin foam without any shinkage or expansion after foaming.A volatile foaming agent composition for thermoplastic resins according to the present invention comprises 1,1,1,2-tetrafluoro-ethane.As the permeability of 1,1,1,2-tetrafluoro-ethane in thermoplastic resins is smaller than that of the air, volatile foaming agent composition containing 1,1,1,2-tetrafluoro-ethane and other kind of volatile foaming agent having permeability higher than that of the air can be regulated to have the permeability similar to that of the air.Accordingly, the permeating speed of volatile foaming agent from the inside of foam cells to the outside and the permeating speed of substituting air into the foam cells from outside can be balanced and any shrinkage or expansion after foaming can be avoided.

Abstract: A flame-retardant polymeric foam which comprises a carbonaceous irreversibly heat set, cellular polymer derived from a stabilized polyacrylonitrile based foam.

Abstract: An adhesive foam comprises a foamed mixture of a foamable homo- or co-polymer and a foamable olefin-unsaturated carboxylic acid copolymer, the mixture containing at least 3 weight percent of polymer units derived from the acid.

Abstract: Fluid polymer/polyol dispersions are prepared from novel polyether polyols.

Abstract: A carrier material usable as such in chromatographic separations or as a starting material which, upon linkage to it of compounds containing ionic groups, ligands or bio-active materials can be used as ion exchanger, as a clinical selective adsorbent, as a medium in affinity chromatography or in enzymatic reactions and consists of a core material obtained by addition polymerization of monomers of which at least 50 mole % consists of (meth)acrylic acid or an ester forming equivalent thereof and a hydrophilic coating material, which is covalently bonded to the core by complete or partial conversion of the carboxyl function with a compound containing at least three carbon atoms and an epoxy group, the epoxy groups that are still present having been converted by etherification and/or hydrolysis to form an ester of a compound containing a hydroxyl group or an oligomer thereof having a molecular weight not higher than 1000, as well as a process for preparing the same.

Abstract: A chlorinated rubber having a chlorine content of 10 to 45% by weight based on the weight of the chlorinated rubber and a Mooney viscosity, ML.sub.1+4 (121.degree. C.), of 10 to 190 is obtained by chlorinating an ethylene/alpha-olefin/non-conjugated diene copolymer rubber containing 5-vinyl-2-norbornene as the non-conjugated diene. The chlorinated rubber has excellent processability in roll milling, extrusion, etc.

Abstract: A filter material is a felt of 60 weight % 2.8 decitex polypropylene fibres and 40 weight % of 3.5 decitex modacrylic fibres.

Abstract: A micro-porous membrane of ultra-high-molecular-weight alpha-olefin polymer having a weight-average molecular weight greater than 5.times.10.sup.5, the micro-porous membrane having through holes 0.01 to 1 micrometer in average pore size, with a void ratio from 30 to 90% and being oriented such that the linear draw ratio in one axis is greater than two and the areal draw ratio is greater than ten. The micro-porous membrane is obtained by forming a gel-like object from a solution of an alpha-olefin polymer having a weight-average molecular weight greater than 5.times.10.sup.5, removing at least 10 wt % of the solvent contained in the gel-like object so that the gel-like object contains 10 to 90 wt % of alpa-olefin polymer, orientating the gel-like object at a temperature lower than that which is 10.degree. C. above the melting point of the alpa-olefin polymer, and removing the residual solvent from the orientated product.

Abstract: Disclosed is a method of making a cross-linked poly(dicyclopentadiene) with a metathesis-catalyst system, where the metathesis-catalyst system contains an organoaluminum or organoaluminum halide activator and a pentavalent tantalum catalyst. In a preferred embodiment, the cross-linked polymer is formed by combining, in a first place, a plurality of reactant streams, one reactant stream which contains the activator, a second reactant stream which contains the catalyst and at least one reactant stream which contains dicyclopentadiene; then injecting the combined reactant streams into a second place, such as a mold, where polymerization occurs. Use of the pentavalent tantalum catalyst results in the formation of a cross-linked polymer having less color and greater transparency than cross-linked poly(dicyclopentadiene) made without a pentavalent tantalum catalyst.

Abstract: A flame retardant polymeric composition comprising a monoalkenyl aromatic polymer having polymerized therein from about 5 to about 25 mole percent of an imide having appended, to the nitrogen atom, a bromine substituted aliphatic hydrocarbon radical. The composition is formed by melt blending a copolymer of a monoalkenyl aromatic monomer and an ethylenically-unsaturated anhydride with a brominated, primary aliphatic amine.

Abstract: A pre-expanded particle suitable for foaming in a mold comprising polyolefin which has a characteristic property that an inclination of slope line obtained on a graph when logarithmic values of melt tension of the polyolefin are plotted as ordinate and reciprocals of absolute temperature at which the melt tension is measured are plotted as abscissa is less than 1,500 is provided. A foamed article produced from the pre-expanded particles has an excellent appearance, a flat surface and good mechanical strength, and is useful for wrapping material, insulating material, a container or a fender of cars.A process for preparing the above-mentioned pre-expanded particles is also disclosed.

Abstract: A method for preparing water-insoluble asymmetric reverse osmosis membranes from water-soluble polymers is disclosed. The method involves casting a polymer film, partially drying it and then contacting it with a transition metal polyvalent ion solution. Optionally, the product of the contacting is cross-linked such as by radiation or heat. The membrane products are disclosed as well.

Abstract: Polymeric polydonor complexons having more than six sites in a structural unit are described. The complexons are of the formulae: ##STR1## wherein P is a linear or three-dimensional polymeric skeleton, x is oxygen or an ##STR2## group wherein R is hydrogen, an alkyl group of 1-6 carbon atoms, a phenyl group or a substituted phenyl group. The described complexons are obtained by reaction of a polymeric compound of the formula P --XH wherein P and X are as defined above with a dianhydride of the corresponding complexon in the presence of a tertiary amine and, optionally, an inert solvent.

Abstract: Textile quality polymeric fibers and thin films that are highly sorbent for organic and other vapors, mists and solutes. The fibers and films comprise a polymeric matrix with a system of interconnecting micropores, and are highly loaded with particulate sorbents such as activated carbon. The fibers and films are manufactured by forming a melt blend of the sorbent particles, the polymer and a selected diluent, spinning or extruding and drawing down the fiber or film, and extracting the diluent. The diluent functions to permit a high spin or extrusion draw down, to permit the subsequent cold drawing of fibers highly-loaded with active carbon, and to permit the fiber or film to be porosified. Optionally, the diluent may be extracted after or before cold drawing, or without any cold drawing. The fibers and films are highly sorbent, are strong and durable and exhibit substantial strength over an appreciable degree of elongation.

Abstract: A flange mountable weatherstrip includes a coated flange cover and a hollow sealing member. The coating and the sealing member are preferably formed in a single extrusion operation of a single low durometer elastomeric sponge material. The preferred physical properties of the elastomeric material and its formulation are described. The flange cover is adaptable to frictionally engage a supporting edge flange. The sealing member is of an asymmetric cross-sectional configuration resembling an upper case letter D.

Abstract: A novel protein adsorbent consisting essentially of a porous copolymer obtained by copolymerizing a monomer mixture comprising at least one cyano group-containing monomer and at least one cross-linkable monomer, said copolymer having an average pore diameter (d) of from 40 A to 9,000 A and a total pore volume of from 0.05.sqroot.X ml to 1.5.sqroot.X ml per gram of the copolymer in a dry state, in which X designates the weight proportion of said cross-linkable monomer expressed in terms of the percent by weight based on the total monomers. The present porous copolymer adsorbent has a remarkably high protein adsorbing capacity. The adorbent can advantageously be used for various purposes such as purification and separation of proteins, and removal of proteins. Copolymer-protein composites obtained by adsorption of proteins on the present porous copolymer also are industrially useful and have a wide variety of applications.

Abstract: There is disclosed an environmentally degradable plastic composition comprising an organic polymeric material having dispersed therein at least one trialkyl ortho ester as a readily autoxidizable organic substance.

Abstract: There is disclosed an environmentally degradable plastic composition comprising an organic polymeric material having dispersed therein at least one unsaturated wax as a readily autoxidizable organic substance.

Abstract: Aromatic sulfonic acid hydrazides and semicarbazides having a sterically hindered phenol group are usable as blowing agents in the manufacture of foamed plastics articles. On heating to about 200 to 300.degree. C. they are splitting off nitrogen and the residue remaining in the foam acts as stabilizer against thermo-oxidative degradation of the plastic material.

Abstract: Bis-tetrazoles wherein the two tetrazole rings are bridged by a direct bond or a divalent organic residue in 5,5'-position or in 1,1'-position have been found to be suitable as blowing agents for thermoplastic resins. They decompose at temperatures of about 230 to 300.degree. C. and therefore can be used for the expansion of resins which are processed at such temperatures, for instance polypropylene, polycarbonates, polyphenyleneoxides or polyamides. Preferred are bis-tetrazoles bridges by aliphatic or araliphatic residues. The expansion can be carried out in an extruder or an injection moulding device.

Abstract: A non-swellable three-dimensional polymer having a component which is a residue of an optically active compound, which residue is chemically removable from said polymer to leave behind in the physical structure of said polymer a void corresponding to the size and shape of said residue of optically active compound, and a particular steric arrangement of functional groups within the void of said polymer corresponding to the chemical structure of said residue of optically active compound, the original polymer having recurring units of the formulas ##STR1## wherein A, C and D are residues bonded to B of compounds which residues are polymerizable or polycondensable and B is a residue of an optically active compound; a process for preparing such polymer and the form of such polymer containing such void and free of the residue of optically active compounds.

Abstract: Markedly improved flame retardance is imparted to crosslinked olefin polymers containing halogenated organic moiety by incorporating therein elemental red phosphorus. The resulting flame retardant compositions are particularly useful in fabrication of crosslinked olefin polymer foams.