Abstract: Improved activation of the blowing agent used to form blown PVC products, as well as thermal stabilization, are provided by a combination of an ester of the formula(R.sup.1).sub.1-2 Sn(--S--R.sup.a --OC(.dbd.O)R.sup.2).sub.2-3wherein R.sup.1 is C.sub.1-4 alkyl, R.sup.a is alkyl, and R.sup.2 is C.sub.6-24 alkyl or alkenyl; one or both of mono (C.sub.1-4 alkyl) and di(C.sub.1-4 alkyl) tin sulfides; a complex of diorganotin oxide with an oxygen-containing acid; and optionally an ester HS--R.sup.c --OC(.dbd.O)R.sup.3 wherein R.sup.c is alkyl and R.sup.3 is C.sub.6-24 alkyl or alkenyl.

Abstract: Fluoropolymer resin is extrusion foamed at low temperature using carbon dioxide as the foaming agent.

Abstract: The present invention relates to a medium density chlorinated polyvinyl chloride foam and the method of preparing such a foam using a blend of chemical blowing agents. The foam having a specific gravity in the range of about 0.3 to about 1.5 comprises chlorinated polyvinyl chloride, a blend of decomposition type blowing agents, a tin stabilizer, a optional impact modifier and a optional high molecular weight process aid.

Abstract: The density of rigid foamed articles made by the thermal decomposition of a blowing agent in a vinyl chloride polymer is reduced by the use of an organotin mercaptoalkylcarboxylate, alone, or in combination with an organotin halide or carboxylate which activate the blowing agent. Sulfides made from said organotin mercaptoalkylcarboxylate are also superior activators of the blowing agent.

Abstract: The density of rigid foamed articles made by the thermal decomposition of a blowing agent in a vinyl chloride polymer is reduced by the use of an organotin halide in combination with a mercaptocarboxylic acid ester or a sulfide of such ester or a mixture of the ester and the sulfide to activate the blowing agent.

Abstract: A fluoroelastomer polymer foam having a compression set value in the range of from about 8.3% to about 43% and closed cell microvoids having diameters of from about 0.002 mm to about 0.048 mm or less, and a method for foaming a fluoroelastomer polymer comprising the steps of dispersing in a fluoroelastomer polymer to be foamed a phenol-based blowing agent to produce a foaming formulation and curing the formulation at a temperature of from about 250.degree. F. (121.degree. C.) to about 450.degree. F. (232.degree. C.) and a pressure of from about ambient to about 3.0 atm.

Abstract: The density of rigid foamed articles made by the thermal decomposition of a blowing agent in a vinyl chloride polymer is reduced by the use of an organotin mercaptoalkylcarboxylate, alone, or in combination with an organotin halide or carboxylate which activate the blowing agent. Sulfides made from said organotin mercaptoalkylcarboxylate are also superior activators of the blowing agent.

Abstract: The density of rigid foamed articles made by the thermal decomposition of a blowing agent in a vinyl chloride polymer is reduced by the use of an organotin mercaptoalkylcarboxylate, alone, or in combination with an organotin halide or carboxylate which activate the blowing agent. Sulfides made from said organotin mercaptoalkylcarboxylate are also superior activators of the blowing agent.

Abstract: Fluoropolymer having unstable end groups is used to form foamed fluoropolymer structures without added blowing agent.

Abstract: This invention relates to porous polyfluoroethylene (PTFE), shaped articles prepared therefrom, and to methods of preparing said articles.

Abstract: Molding composition based on fluoropolymers and process for producing foam material therefromThe invention relates to a molding composition based on fluoropolymers which additionally contain from 1 to 50% by weight of at least one polymer containing sulfoxide groups. The polymer containing sulfoxide groups comprises, in particular, polyarylene sulfoxide units of the formula:--(--C.sub.6 H.sub.4 --SO--)--.

Abstract: A foam cell nucleating agent that is a combination of sulfonic or phosphonic acid or salt thereof and inorganic salt containing a polyatomic anion yields improved foaming of thermoplastic resins such as polyolefins and melt-fabricable fluoropolymers.

Abstract: A resin composition for low expansion moldings which comprises (A) 20 to 80 parts by weight of a vinyl chloride resin having an average degree of polymerization of from 500 to 1700 and (B) correspondingly from 80 to 20 parts by weight of a copolymer made of 60 to 90 parts by weight a polymerizable monomer mixture consisting of 20 to 40 wt % of acrylonitrile, 20 to 60 wt % of .alpha.-methylstyrene and 20 to 40 wt % of styrene and, correspondingly, 40 to 10 parts by weight of a crosslinked acrylic rubber. The resin composition further comprises (C) 0.5 to 30 parts by weight of an acrylic resin having a reduced viscosity of not less than 3.0 dl/g when measured by use of a chloroform solution of the acrylic resin at a concentration of 0.1 g/100 ml, (D) 0.1 to 10 parts by weight of a thermally decomposable rosining agent, and (E) from 1 to 10 parts by weight of a stabilizer, each based on 100 parts by weight of a mixture of the components (A) and (B).

Abstract: The density of rigid foamed articles made by the thermal decomposition of a blowing agent in a vinyl chloride polymer is reduced by the use of an organotin halide in combination with a mercaptocarboxylic acid ester or a sulfide of such ester or a mixture of the ester and the sulfide to activate the blowing agent.

Abstract: The present invention describes a method for preparing an asymmetric porous membrane by a dry-wet phase inversion method, which comprises contacting a cast or spun polymer solution with water or organic vapor prior to immersing into the non-solvent precipitation medium, whereby said water or organic vapor is adsorbed onto the cast or spun polymer solution. Higher permeability and excellent rejection ability can be obtained, due to the high porosity and uniform pore size of said membranes according to the present invention.

Abstract: In the present invention a blend of resin composition and blending technique is optimized to provide a desired balance of node size and fibril length with the additional property of thermal stability in the resulting stretched material.The stretched blend can be described as a polytetrafluoroethylene porous material having a microstructure of nodes interconnected by fibrils in which the material comprises a blend of two different polytetrafluoroethylenes, one polytetrafluoroethylene being a homopolymer of tetrafluoroethylene and the other polytetrafluoroethylene being a modified polymer of tetrafluoroethylene.

Abstract: A foamed polyvinylchloride (PVC) material is produced by mixing of 100 mass parts of PVC with 0.5-5 mass parts of sodium alkyl sulfonate, molding of the obtained composition and followed by heating for foaming at 190.degree.-300.degree. C. for 3-20 mins. Molding is performed either under 0.5-400 MPa and 20.degree.-170.degree. C., followed by heating to 140.degree.-150.degree. C. in the closed space, or in a free state in the form of 2-16 mm thickness layer. In the latter case the layer before foaming can be subjected to packing.

Abstract: A thermal insulator of the present invention includes a foam containing solidified CO.sub.2 gas. A method for producing the thermal insulator includes the steps of: mixing a metal compound selected from the group consisting of a metal oxide and a metal hydroxide, water, a polyol component, and an isocyanate component to generate a mixture; foaming the mixture in a container to generate closed-cells made of a water-foamed polyurethane; and allowing CO.sub.2 gas generated during the foaming step to react with the selected metal compound to solidify the CO.sub.2 gas, thereby depressurizing the closed-cells in the closed-celled foam.

Abstract: The present invention provides a vinyl chloride resin composition capable of providing a molded product having a uniform-and-fine-cell structure, a smooth surface and a small linear expansion coefficient. The composition comprises 100 parts by weight of (A) a vinyl chloride resin, 0.5-30 parts by weight of (B) a methacrylic acid ester copolymer resin, 0.5-30 parts by weight of (C) a chlorinated polyethylene resin, 25-60 parts by weight of (D) talc, and (E) a blowing agent.

Abstract: There is provided a polytetrafluoroethylene (PTFE) porous material which has improved adhesion and improved buckling resistance on bending without a tearing problem along a tubular axial direction.The porous material is composed of a polytetrafluoroethylene and a heat-meltable resin of which melting point is lower than that of the polytetrafluoroethylene, has fibril portions and node portions and characterized in that the fibril portions are mainly of the polytetrafluoroethylene, and the heat-meltable resin mainly constitutes the node portions and hardly constitutes the fibril portions.

Abstract: Improved activation of the blowing agent used to form blown PVC products, as well as thermal stabilization, are provided by a combination of an ester of the formula(R.sup.1).sub.1-2 Sn(--S--R.sup.a --OC(.dbd.O)R.sup.2).sub.2-3wherein R.sup.1 is C.sub.1-4 alkyl, R.sup.a is alkyl, and R.sup.2 is C.sub.6-24 alkyl or alkenyl; one or both of mono (C.sub.1-4 alkyl) and di(C.sub.1-4 alkyl) tin sulfides; a complex of diorganotin oxide with an oxygen-containing acid; and optionally an ester HS--R.sup.c --OC(.dbd.O)R.sup.3 wherein R.sup.c is alkyl and R.sup.3 is C.sub.6-24 alkyl or alkenyl.

Abstract: A bone inducing material comprising a piezoelectric porous membrane having through-holes of an average pore size of about 0.1 to 5 .mu.m is disclosed. When the bone inducing material according to the present invention is used, bone is rapidly regenerated, and new formation of bone occurs. The bone inducing material is particularly useful in the dental field, for example, for treatment of periodontal diseases by GTR method.

Abstract: An expandable poly(vinyl chloride) resin composition for use in powder molding process containing a granular poly(vinyl chloride) resin, a fine-granular poly(vinyl chloride) resin, a plasticizer, a stabilizer, a foaming agent and an alkyl phosphate gives by a powder molding process an expansion-molded article having remarkably strengthened foamed cells and free from the occurrence of surface unevenness caused by polyurethane backing.

Abstract: A substantially cylindrical bar of microporous PTFE is non-fibrillated and incorporates pores within any cylindrical surface within the bar centred about the central longitudinal axis of the bar that are of substantially uniform size and are substantially uniformly distributed within that surface. The process for producing such a bar includes the step of applying a substantially radial compressive force to pre-heated and cooled granules of PTFE and subsequently re-heating and cooling the compressed granules, while a film of non-fibrillated, microporous PTFE is formed from the cooled bar, the plane of the film being perpendicular to the direction of the radial compressive force whereby the pores within any plane substantially perpendicular to the thickness of the film are of substantially uniform size and are substantially uniformly distributed within that plane and all such parallel planes.

Abstract: A porous polytetrafluoroethylene (PTFE) structure particularly for use as a liquid filter comprises particles of granular-type PTFE fused together to form a porous integral network. The structure is formed by spraying an aqueous suspension of granular PTFE particles and baking at a temperature of 335.degree.-350.degree. C. Typically the specific gravity is 0.8 to 1.54. The crystallinity is less than 95%. The structure may be supported on a perforate substrate such as stainless steel mesh.

Abstract: A crosslinked foamed body obtained by subjecting a rubber compounded product comprising (A) a chlorinated ethylene/.alpha.-olefin copolymer rubber, (B) a triazinethiol as a vulcanization agent, (C) an alkyl ammonium halide as a vulcanization promotor, and (D) a hydrazide-type blowing agent to two step vulcanization and foaming at a vulcanization temperature of 120.degree. to 140.degree. C. for a vulcanization time of 5 to 10 minutes in a first step and at a vulcanization temperature of 125.degree. to 160.degree. C. for a vulcanization time of 5 to 20 minutes in a second step, the second step vulcanization temperature being higher than the first step by at least 5.degree. C., so that the expansion factor will be 3 to 10 times. This crosslinked foamed body can be colored brilliantly, exhibit excellent weatherability, suppleness and shape retention as well as good outer appearance. This product is well usable, for example, as wet suits.

Abstract: A silicone sponge rubber having a great tensile strength even when it has a low foam density can be obtained from a foamable silicone rubber composition including:(A) a polyolefin dispersion obtained by polymerizing monomers having polymerizable aliphatic unsaturated double bonds, dispersed in a dispersion medium of an organopolysiloxane having a viscosity of from 50 cSt to 1,000,000 cSt at 25.degree. C. whose molecular chain both terminals are terminated with silanol groups, to form a polyolefin in the silanol group-containing organopolysiloxane;(B) an organohydrogenpolysiloxane having at least two hydrogen atoms in one molecule;(C) at least one selected from the group consisting of water, an alcohol, a silanol group-containing organosilane, and a silanol group-containing siloxane having a viscosity of less than 50 cSt at 25.degree. C.; and(D) a platinum family metal catalyst.

Abstract: Shaped microcellular structures having substantially non-cellular skins are produced from reactive liquid polymer systems incorporating thermoplastic microspheres containing volatile materials such as low boiling point halogenated or non-halogenated organic materials. Use of thermoplastic microspheres encapsulating such volatile materials facilitates the removal of the shaped foamed structure from molds, eliminating the need for release agents. Various products based on this process, such as bathroom fixtures, bicycle and wheel chair tires, shoe soles, and automotive parts, are provided.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 .mu.m, provided further that the number average ratio of particles smaller than 53 .mu.m is greater than 80%, the remaining larger particles being in the size range from 53 .mu.m to 180 .mu.m. A powder with slow recrystallization rates, as evidenced by non-overlapping or slightly overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10.degree. C. to 20.

Abstract: An improved foam nucleation system based on selected boron nitride provides smaller foam cell size for melt-fabricable fluoropolymers.

Abstract: Disclosed is a compatibilized carbon black useful in melt processing of plastic material. The carbon black is coated with a compatibilizing agent which enhances the dispersibility of the carbon black in a melt of the plastic material. Further disclosed are processes for making plastic foam structures with the compatibilized carbon black.

Abstract: A high degree of stabilization of flexible PVC is achieved by using a perchlorate and a terminal epoxide compound.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 .mu.m, provided further that the number average ratio of particles smaller than 53 .mu.m is greater than 80%, the remaining larger particles being in the size range from 53 .mu.m to 180 .mu.m. A powder with slow recrystallization rates, as evidenced by non-overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10.degree. C. to 20.degree. C.

Abstract: The invention provides pyrotechnic sheet material comprising a substrate of porous, vapour-permeable oxidizing polymeric film, for example a halogenopolymeric film, having a layer of oxidizable material for example magnesium, on at least part of its surface, the substrate and the oxidizable material being conjointly capable of reacting together on ignition. Advantageously at least part of the oxidizing material is accommodated within the polymer pores.The pyrotechnic sheet material burns faster than material comprising solid polymeric film.

Abstract: A polyvinylidene fluoride porous membrane has an asymmetrical structure, excellent mechanical strength such as tensile strength at break and elongation at break, and a desirable narrow range of pore diameter distribution. A method of preparing the porous membrane is also disclosed. The membrane comprises a vinylidene fluoride resin having an inherent viscosity from 1.3 to 15.0 (dl/g), and the membrane comprises pores which satisfy the following numerical expression (A):4.0<P.sub.1 /P.sub.2 .ltoreq.10.00 (A)wherein P.sub.1 is an average pore diameter (.mu.m) in a surface which has a larger average pore diameter, and P.sub.2 is an average pore diameter (.mu.m) in the other surface of the membrane.

Abstract: A substantially cylindrical bar of microporous PTFE is non-fibrillated and incorporates pores within any cylindrical surface within the bar centred about the central longitudinal axis of the bar that are of substantially uniform size and are substantially uniformly distributed within that surface. The process for producing such a bar includes the step of applying a substantially radial compressive force to pre-heated and cooled granules of PTFE and subsequently re-heating and cooling the compressed granules, while a film of non-fibrillated, microporous PTFE is formed from the cooled bar, the plane of the film being perpendicular to the direction of the radial compressive force whereby the pores within any plane substantially perpendicular to the thickness of the film are of substantially uniform size and are substantially uniformly distributed within that plane and all such parallel planes.

Abstract: Novel porous copolymers are disclosed which can be used to prepare ion-exchange resins and polymeric adsorbents. The copolymers comprise a copolymer of at least one monovinylidene monomer and a crosslinking monomer and have a unique cellular pore structure. The cellular structure comprises a macroporous void phase which is dispersed within a continuous copolymer phase. The porous void phase comprises a plurality of cellular void spaces which are at least partially enclosed by walls of the continuous copolymer phase. Also disclosed are processes which can be used to prepare the porous copolymers, as well as ion-exchange resins and polymeric adsorbents using the porous copolymers.

Abstract: Novel compositions containing an ECTFE polymer and PTFE particles dispersed therein, and insulated wires and cables, especially local area network (LAN) cables in which the conductors are covered by foamed insulation made from such compositions.

Abstract: A method for separating co-mingled polymeric materials, in particular polyethylene terephthalate (PET) and polyvinyl chloride (PVC) is described. The process involves selectively dissolving a supercritical fluid into one of the materials at the appropriate temperature and pressure. Upon rapid reduction of the system pressure, the selected material foams providing a change in density. Under ambient conditions, the polymeric materials having a large density difference can be separated by means of aqueous separation and flotation. The preferred supercritical fluid for the process is carbon dioxide, and PVC is the material into which the supercritical fluid is preferentially dissolved.

Abstract: A new porous polytetrafluoroethylene (PTFE) and a process for the production thereof is provided. Both the PTFE and the process excel by the fact that polytetrafluoroethylene is radiation-chemically degraded, the degraded polytetrafluoroethylene is mixed with a high-molecular emulsion polymerisate of polytetrafluoroethylene and the mixture is extruded, stretched and may additionally be sintered.

Abstract: A new porous polytetrafluoroethylene (PTFE) and a process for the production thereof is provided. Both the PTFE and the process excel by the fact that polytetrafluoroethylene is radiation-chemically degraded, the degraded polytetrafluoroethylene is mixed with a high-molecular emulsion polymerisate of polytetrafluoroethylene and the mixture is extruded, stretched and may additionally be sintered.

Abstract: Anti-corrosive protective compositions for metal. The composition contains a curable binder, which after curing has low water and oxygen permeability, and at least one filler composed of solid parts, characterised in that the filler contains expanded polymer parts with a size of 1 to 100 micrometer.

Abstract: Disclosed is a compatibilized carbon black useful in melt processing of plastic material. The carbon black is coated with a compatibilizing agent which enhances the dispersibility of the carbon black in a melt of the plastic material. Further disclosed are processes for making plastic foam structures with the compatibilized carbon black.

Abstract: Foamable thermoplastic resin compositions are provided having vinyl chloride polymer, a graft copolymer having a superstrate grafted to a substrate wherein the superstrate has alphamethyl styrene, unsaturated nitrile, and unsubstituted styrene therein, and the substrate is a butadiene rubber, a rubber-free copolymer having alkylmethacrylate, vinyl aromatic, and unsaturated nitrile therein, and a chemical blowing agent. The foamable thermoplastic resin composition may be coextruded with a non-foamed thermoplastic resin skin to produce a coextruded rigid foamed structure by a process of coextruding the skin and foamable thermoplastic composition. The composition and process are useful for making coextruded rigid foam structures which are useful in rigid foam applications such as foamed pipe and foamed sheet.

Abstract: Particles of a fine powder of a thermoplastic synthetic resin (host powder) having a suitable broad range between its initial glass transition temperature (initial T.sub.g) and its final T.sub.g, are partially coated with an anti-caking coating powder (coating powder) by blending at an elevated temperature to form "mottled" particles. The elevated temperature is defined in relation to the initial and final T.sub.g s as: (initial T.sub.g -20).degree. C. but below the final T.sub.g. Mottled particles, without being encapsulated, have the unique ability to maintain their individual particulate characteristics at a temperature at least 10.degree. C. above the initial T.sub.g of the uncoated host powder, and flow freely under applied pressure. Such pressure is applied by a rolling drum which spreads the mottled particles onto a target bed where they are selectively sintered With a controlled high energy beam, usually a laser beam.

Abstract: Controlled foams of crystalline amorphous polymers include a second phase polymeric material having a transition temperature below that of the matrix polymeric material. The second phase material provides nucleating sites for the growth of gas formed cells which are limited in size by the particle size of the second phase polymeric material.

Abstract: A cellular, foamed-polymer product is disclosed, which is constituted by a mixture comprising: at least one isocyanate, at least one anhydride, at least one vinylidene compound, poly-(vinyl chloride), at least one foaming agent, a heat stabilizer, calcium stearate and zinc stearate.The product production scraps and processing wastes and residues are not riskful for health and environment, and can be disposed of as "waste similar to solid municipal waste".

Abstract: Perfluorotripentylamine, perfluoropolyether or another such high-boiling liquid is added as a foaming agent to a thermoplastic fluororesin such as a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin or a tetrafluoroethylene-hexafluoropropylene copolymer resin. Because the vapor pressure of said foaming agent in the molten fluororesin is lower than that of Freon or another such low-boiling foaming agent, the cells in the foam can be made fine and uniform in diameter.

Abstract: An expanded polymer product with high distortion temperature, high flame resistance and low smoke toxicity and opacity comprises, in combination:between 18% and 25% of a mixture of at least two isocyanates;between 8% and 11% of a styrene and maleic anhydride mixture;between 19% and 42% of a PVC resin in emulsion form;between 4% and 7% of at least one expanding agent;between 0.5% and 1% of at least one temperature stabilizer;between 16% and 40% of TiO.sub.2.Said product is used particularly in sea, ground and air transport, and in numerous constructional applications in which the materials must combine high technical characteristics with adequate lightness.

Abstract: A foam spacer which is usable as a cork substitute in the base cushion layer of a glass spacer. The spacer, which is adapted to replace natural cork spacers is preferably laminated to a tack layer or otherwise adhered to a surface. The spacer is formed from a plasticized foamable resin which includes a quantity of incorporated reinforcing agents.