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 foamed polyarylene sulfide according to the invention has a density which is reduced by at least 50% compared with the theoretical density of nonfoamed material, and is expediently produced by subjecting a polyarylene sulfoxide as such or a mixture of one or more polyarylene sulfides with a polyarylene sulfoxide to heat treatment. The temperature of the heat treatment is in the range from 250.degree. to 400.degree. C.

Abstract: Molding compositions or mixtures comprising a high-temperature-resistant polymer and at least one polymer containing sulfoxide groups are used for the production of a foam by exposure to heat. The foam is employed for heat-resistant insulating layers.

Abstract: The invention relates to a process for making a foamed polymer. The process involves (a) dispersing thermally degradable solid particles in polymer precursor; (b) crosslinking the polymer precursor to form a rigid, crosslinked polymer without degrading the particles; and (c) heating the polymer to degrade the particles and form the polymer foam.

Abstract: A composition includes a polymethacrylimide polymer which is polymerized in the presence of an epoxy resin and a flame-inhibiting agent. Further, a process is described for making flame-resistant polymethacrylimide, which includes mixing an epoxy resin and a flame-inhibiting agent with a methacrylic acid and methacrylonitrile, and polymerizing. A polymethacrylimide foam so prepared has an LOI value of at least 25 and retains the good mechanical properties that are associated with polymethacrylimide foams.

Abstract: A formed thermoplastic resin article is made of a thermoplastic resin and a foamed elastic polymer finely dispersed in the thermoplastic resin. The formed thermoplastic resin article can be produced by blending an elastic polymer, in which an endothermic foaming agent decomposable at a temperature of at least 160.degree. C. was mixed in advance at a temperature lower than a decomposition temperature of the endothermic foaming agent, in a thermoplastic resin and then plasticizing and forming the resultant resin blend at a temperature at least equal to the decomposition temperature of the endothermic foaming agent.

Abstract: Process and intermediate for preparing an intrinsically foamed thermoplastic polymer comprising a vinyl monomer and maleic acid and/or maleic anhydride, in which process a polymer composition comprising:a) a core polymer based ona.1) 12-50 moles % maleic acid and/or maleic anhydridea.2) a vinyl monomer, anda.3) optionally a third monomer, where the sum total of a1+a2+a3 is 100 moles % and the weight average molecular weight of the core polymer is 50000-500000, andb) optionally a nucleating agent, is introduced into equipment suited for making foam, in which process the core polymer, and optionally the nucleating agent, are brought to a temperature which is high enough to release CO.sub.2 from the core polymer, and in which process the polymer melt is expanded to form a polymer foam with the desired density. The core polymer is preferably a polymer of styrene and maleic anhydride.

Abstract: There is disclosed an ethylene polymer composition including a low density ethylene polymer blended with from about 2.0% by weight to about 60.0% by weight of the total composition of a recycled high density ethylene polymer and a compatibilizer comprising from about 0.1% to about 1.5% by weight zinc oxide and about 0.1% to 2.0% by weight of glycerol monostearate. The polymer composition may also include a foaming agent is present in an amount from 5 to 30 parts per hundred. There is also provided a method for producing the ethylene polymer compositions.

Abstract: The presence in foamable, curable organosiloxane compositions of a hydrogenated glyceride of an ethylenically unsaturated carboxylic acid imparts sufficient thixotropy to the uncured composition to inhibit flow without adversely affecting desirable properties of the cured foam such as density and texture.

Abstract: Method for the production of organosiloxane elastomeric foam comprising mixing together (A) a polydiorganosiloxane having at least two silicon-bonded alkenyl groups, (B) an organohydrogensiloxane, (C) a platinum catalyst, (D) an .alpha., w-diol of formula HOROH wherein R represents an alkylene group having 3 to 7 carbon atoms and (E) a resin copolymer of R'.sub.3 SiO.sub.0.5 units and SiO.sub.2 units, R' being selected from methyl and vinyl, and thereafter allowing the mixture to foam and cure.

Abstract: A process for producing a high quality silicone foam by free foaming, in which a two-component addition crosslinking system is used, comprised of a component A which contains a silicone polymer having at least two double bonds per molecule, preferably vinyl groups, a complexed organo-platinum for example with butanol, fumed silica, and water, as well as further additives, if appropriate, and a component B which contains a silicone polymer having at least two double bonds per molecule, preferably vinyl groups, fumed silica, and polydimethyl hydrogen siloxane as SiH crosslinking agent. The two components A and B are mixed, and the reaction mixture is subsequently pressurized, preferably using compressed air or nitrogen, in a storage vessel over several hours so that the gas is present in the mixture in a dissolved form.

Abstract: A method of and apparatus for continuously foaming a polyimide prepolymer powder which is not susceptible to heating by microwave energy utilize a preheated conveyor belt to heat the powder in contact with and adjacent the surface of the conveyor belt to commence the reaction and foaming of the powder as it enters an oven which further heats the powder by convection and infrared radiation to form a continuous foam bun. The conveyor belt is cooled as it exits the oven to cool a bottom surface of the foam product to enable the foam product to be removed from the conveyor before interior portions of the foam product have cooled. Foam adhering to the conveyor belt, after the product has been removed, is cleaned from the conveyor belt, collected and mixed with and used as a filler in the prepolymer powder used in the process. In addition the mass of the powder entering the oven and the density and degree of cure of the foam bun exiting the oven are monitored to continuously control the process.

Abstract: A method for treating the surface of a thin porous film material of tetrafluoroethylene resin is disclosed, which comprises heating said surface to a temperature higher than the thermal decomposition point of said resin so as to decompose and remove part of said surface. The resulting thin porous film material of tetrafluoroethylene resin has an adhesive surface while retaining the desired pore size, hardness, and degree of penetration of adhesive.

Abstract: There is disclosed a process for producing alkenyl aromatic foams utilizing a combination of atmospheric and organic gases as blowing agent, preferably using greater than 30% by weight of atmospheric gas, and preferably also using a predetermined about of a masterbatch mix comprising a styrenic polymer, a rubbery block copolymer, and a solid blowing agent. Also disclosed are alkenyl aromatic foams produced by the process which exhibit increased densities, increased thermoforming capabilities, increased post-expansion properties, and increased retainment of the atmospheric and organic gases.

Abstract: The presence in curable, foamable organosiloxane compositions of an organosiloxane containing at least one diphenylsiloxane unit, a triorganosiloxane unit and a silanol group imparts a high expansion ratio, an excellent moldability, and an excellent storage stability, and that is not subject to post-cure whitening.

Abstract: The present invention provides expandable plastics having a molecular weight of 50,000 to 500,000 which comprises the following structural units (I), (II) and (III) giving a foam having heat resistance and fine structure by heating, the molar ratio of (I+II) to (III) being 1 to 0.6-1.5 and the proportion of (I) being 5 to 50 wt. % of the total components: ##STR1## wherein R represents a hydrogen atom or a methyl group. When the copolymer, the expandable plastics, of the present invention is used, white foams having a very fine texture are obtained without using special foaming agents, and besides the heat resistance of the foams is high and the amount of water absorbed thereby is little. The foams of the present invention, therefore, can be used in a wide range as soundproofing materials and heat insulators for which the conventional foams cannot be used because of their low heat resistance, and substitutes for honeycomb structures used in airplanes.

Abstract: A method for treating the surface of a thin porous film material of tetrafluoroethylene resin is disclosed, which comprises heating said surface to a temperature higher than the thermal decomposition point of said resin so as to decompose and remove part of said surface. The resulting thin porous film material of tetrafluoroethylene resin has an adhesive surface while retaining the desired pore size, hardness, and degree of penetration of adhesive.

Abstract: Expanded material obtained by heating a composition comprising at least one hermosetting nadimide resin, said heating being performed at a temperature and during a period which are sufficient to cause the expansion of said composition by release of cyclopentadiene. A nadimide resin of the polyimide type and having a number average molecular weight of 600 to 10,000 is preferably used. The composition further comprises preferably 1% to 50% by weight of a linear, preferably thermostable polymer.

Abstract: The invention provides a foamable organopolysiloxane composition capable of giving, by foaming and curing at room temperature, a silicone rubber foam of high foaming expansion having very uniform and dense cellular structure. The composition is prepared by a process comprising the steps of: (A) compounding an .alpha.,.omega.-dihydroxy dimethylpolysiloxane with a reinforcing silica filler, hexamethyl disilazane and water as the hydrolysis agent of the silazane to give a compound; (B) removing ammonia in the compound formed by the hydrolysis of the silazane compound as completely as possible; and (C) compounding the compound with a polyhydroxy methylpolysiloxane, an organohydrogenpolysiloxane and a platinum compound as a catalyst for the dehydrogenation reaction between the silanolic hydroxy groups and the silicon-bonded hydrogen atoms to produce hydrogen as the foaming gas.

Abstract: A foaming polysiloxane composition providing excellent expansion ratio and expansion control comprising: (A) 100 parts by weight of an .alpha., .omega.-dihydroxyorganopolysiloxane, (B) 0.01-50 parts by weight of an organopolyhydroxypolysiloxane, (C) an organopolyhydrogensiloxane wherein 1 molecule contains at least 2 units represented by the general formula: ##EQU1## and in such quantity that SiH lies within the range of 0.5-30 mole per mole of total silanol groups in components A and B, (D) platinum or platinum compounds in a quantity of 0.1-200 ppm calculated as platinum metal per total weight of said components A, B and C, and (E) an organosilicon compound with acetylenic unsaturated groups in a quantity of 0.001-10 parts by weight per 100 parts by weight of components A,B,C and B; and a cured product thereof were disclosed.

Abstract: A process for producing cellular foamed articles from high temperature engineering polymers wherein polymeric blowing agents are utilized to expand the polymers. The process comprises mixing a first polymer capable of being foamed with a second polymer comprising at least one poly(alkylene carbonate) to provide a polymer blend; heating the polymer blend to a temperature sufficient to melt the polymer to be foamed and to decompose the second polymer to form gas inclusions within the first polymer; expanding the melted first polymer containing the gas inclusions to form a foamed article; and cooling the foamed article to a temperature below the melting or softening point of the foamed article. Polymers which may be foamed according to the process include those polymers which can tolerate processing temperatures in excess of 260.degree. C.

Abstract: The present invention is directed to a process for the production of compact or cellular, elastomeric moldings having a compact skin based on polyurethane urea elastomers prepared from(a) organic polyisocyanates,(b) relatively high molecular weight polyhydroxyl or polyamino compounds containing at least two reactive hydrogen atoms,(c) diaminodiphenyl ureas as chain-extending agents and optionally,(d) catalysts,(e) small quantities of ethylene glycol,(f) other chain-extending agents and/or cross-linking agents,(g) blowing agents and(h) auxiliaries and/or additives, which is characterized in that the chain-extending agents (c) are diaminodiphenyl ureas corresponding to formula I ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 may be the same or different and represent hydrogen or a C.sub.1 -C.sub.6 alkyl radical and wherein the NH.sub.2 groups are in the m- and/or p-position to the urea group.The present invention is also directed to the RIM elastomers produced by this process.

Abstract: A method is provided for reducing the density of silicone foam resulting from the generation of hydrogen gas by employing a hydride polysiloxane in the form of a mixture of linear hydride polysiloxane and cyclic hydride polysiloxane. Aqueous methanol is also found to be an effective density-reducing agent.

Abstract: Described are ways of improving the yields of specification grade polyimide foam on a consistent basis from one run to the next, by use of improved microwave-based foaming processes. In one such process, during the application of the microwave radiation, the body of polyimide precursor and of the foam structure as it is developing therefrom are maintained under a substantially vapor-impermeable mmicrowave-compatible shroud that does not substantially restrict or impede development of the foam structure; and the microwave radiation is directed upon the top, sides and ends of the body of polyimide precursor and of the foam structure as it is developing, but the extent to which such radiation impinges upwardly into the bottom of said body and said foam structure is curtailed, preferably by means of a metallic shield located below the precursor and developing foam structure.

Abstract: This invention relates to a process for the production of high strength polybenzimidazole filaments and molded products made from such filaments. The filaments produced by this process contain from about 10 to about 50 percent by weight residual solvent and can be heated at a temperature of about 350.degree. C. to about 600.degree. C. to produce three-dimensional foamed articles.

Abstract: Open-cell structures are filled with polyimide foam formed in place by the use of a foam precursor in powdered form comprised of a combination of (a) the reaction product of an excess of organic polyisocyanate and a member selected from the group consisting of furfuryl alcohol and condensation products thereof, and (b) an organic polycarboxylic compound containing two carboxylic anhydride groups. The precursor is prepared by combining the species under conditions which favor the reaction of the furfuryl alcohol with the polyisocyanate, but not the polyimide-forming reaction. The polyimide-forming reaction itself is then performed by adding preselected amounts of the powdered precursor, depending on the desired ultimate density of the foam, to each cell of the open-cell structure, then heating to initiate the polyimide reaction, and permitting the carbon dioxide generated by the reaction to escape while confining the resulting foam to the cells.

Abstract: Plastic foams are prepared by reacting a compound containing Si-bonded hydrogen and at least one SiC-bonded radical having a basic nitrogen atom in the same molecule with a hydroxyl-containing compound.

Abstract: A process for producing an expanded or foamed body of a fluorocarbon resin comprising molding the resin in a molten state in the presence of a depolymerizable polymer, polyether or polycarbonyloxy compound.

Abstract: Organopolysiloxane compositions adopted for easy conversion into burn resistant foams useful, e.g., for the protection of nuclear power installations, include admixture of various organopolysiloxane polymers comprising SiH, SiOH, SiR.sub.3 and Si-vinyl functions, and notably a hydroxylated liquid resin containing CH.sub.3 SiO.sub.1.5 and (CH.sub.3).sub.2 SiO units, or reaction product of a hydroxylated MQ resin with a hydroxylated polyorganosiloxane oil, or mixture thereof.

Abstract: The present invention is a process for the preparation of novel polybenzimidazole foams. The foams exhibit a closed cellular structure and are prepared by forming a polybenzimidazole solution, adding sulfuric acid to the polybenzimidazole solution, removing the solvent, and heat treating the polybenzimidazole at a temperature of about 350.degree. to 600.degree. C.

Abstract: A liquid impregnant containing furfural, an acid catalyst and a pore-forming agent comprising a surfactant, e.g. a polyalkylene oxide adduct, is impregnated into fine grained, isotropic graphite bodies and then polymerized and pyrolyzed. An increase in the density of the impregnated body and an improved surface finish is obtained by means of the liquid impregnant and method of this invention.

Abstract: The present invention provides a porous chitin shaped article which has a wet strength of not less than about 1 g/mm.sup.2. The shaped article has preferably a porosity of more than 90%.The present invention also provides a process for preparing the above chitin shaped article, which comprises:dissolving chitin in a solvent to form a dope, dispersing a water-soluble polymer, which is solid at ambient temperature, in said dope to form a coagulated article, andremoving the water-soluble polymer from said coagulated article by treating with aqueous solution.

Abstract: Non-oxide refractory foams, possessing controlled permeability and uniformity, are prepared by impregnating an organic polymer foam material with a fluid, particulate slurry of a first refractory material, drying, applying to the dried, impregnated material a second refractory material which has a lower melting point than the first refractory material and thereafter heating, at a temperature sufficient to cause melt infiltration of the second refractory material into the impregnated material, thus producing inert and dimensionally stable composite refractory foams having broad utility as particulate filters or carriers.

Abstract: Methods of making modified polyimide compositions and the resulting compositions. A polyimide forming material is prepared by treating an aromatic dianhydride with an esterifying solvent, then adding a suitable diamine. In order to obtain a foam which is non-friable and resistant to repeated compressive forces, the selected diamine must contain an aliphatic moiety in the chain. This material is dried to a powder or film. A foam is produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient, flexible non-friable foam.

Abstract: A liquid impregnant containing furfural, an acid catalyst and a pore-forming agent comprising a surfactant, e.g. a polyalkylene oxide adduct, is impregnated into fine grained, isotropic graphite bodies and then polymerized and pyrolyzed. An increase in the density of the impregnated body and an improved surface finish is obtained by means of the liquid impregnant and method of this invention.

Abstract: Methods of making modified polyimide compositions and the resulting compositions. A polyimide forming material is prepared by treating an aromatic dianhydride with an esterifying solvent, then adding a suitable diamine. In order to obtain a foam which is non-friable and resistant to repeated compressive forces, the selected diamine must contain an aliphatic moiety in the chain. This material is dried to a powder or film. A foam is produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient, flexible non-friable foam.

Abstract: Polyorganosiloxane foams exhibiting a desirable combination of low density, an average cell size between 0.2 and 4 mm and a cell concentration of at least 4 per linear centimeter are obtained by dispensing and curing moisture curable organosiloxane compositions containing a dispersed liquid or gaseous blowing agent and, as a foam stabilizer, a resinous organosiloxane copolymer comprising trimethylsiloxy units, SiO.sub.4/2 units and fluorine-containing organosiloxane units. The polymer portion of the organosiloxane compositions can be a polydimethylsiloxane or a graft copolymer comprising at least 20 mole percent of dimethylsiloxane units in combination with organic units.

Abstract: Methods of making modified polyimide/polyimide-amide foams having selected compressive resistance and density characteristics and the resulting compositions. A suitable aromatic dianhydride is mixed with a suitable oxoimine and alcohol, which initially is believed to form a monoimide which is substantially/simultaneously esterified by the alcohol. To this mixture is added a suitable diamine to produce a polyimide forming material. This material is dried to a powder or film. A foam is produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient flexible foam. Depending upon heating conditions, a polyimide, polyimide-amide or mixture thereof may be produced, resulting in foams having varying physical properties. Within the mole ratio range of oxoimine to dianhydride of about 1.5:1 to about 0.

Abstract: The flowability of foamable compositions comprising a hydroxyl-containing polyorganosiloxane, a polyorganosiloxane containing silicon-bonded hydrogen atoms, a platinum catalyst and a catalyst inhibitor is eliminated by including in the composition a solid filler exhibiting a mean particle size of one micron or less and either (1) organosilicon compound containing at least 0.5% by weight of carboxyl groups or silicon-bonded hydroxyalkyl groups, or (2) a partially esterified polyfunctional alcohol. In addition, the pot life of the composition is increased without adversely affecting the structure of the cured foam or the adhesion of the foam to various substrates.

Abstract: A sprayable, modified polyisocyanurate solid or foam composition, with fast reaction times and excellent fire properties and capable of being sprayed in a one-to-one, fixed-volume spray system, is prepared by the reaction of a low-functionality MDI, with a polyol composition comprising a methoxy polyethylene glycol and a methyl glucoside polyol, the reaction carried out in the presence of a trimerization catalyst, to provide a sprayable polyisocyanurate composition particularly useful for spraying upright and overhead surfaces, due to the fast reaction time and rapid cure.

Abstract: Compositions that cure rapidly to produce silicone foams and protective coatings are disclosed. These compositions comprise: (A) a certain liquid copolymeric polyorganosiloxane; and (B) an amino functional silicone polymer. For example, simple mixtures of the liquid copolymeric polyorganosiloxane and a polydiorganosiloxane having aminoalkyl substituents can be mixed together to form a resilient silicone foam. If the foam compositions are further provided with certain mineral fillers, a high degree of fire resistance is attained.

Abstract: There are provided methods for making heat-resistant, foamed, crystalline plastic materials. For example, polyethylene terephthalate may be foamed with a polycarbonate, extruded into a foamed sheet and this foamed sheet may be thermoformed by being subjected to crystallization annealing. The thermoformed, foamed, crystalline plastic sheets prepared by this process are particularly useful for forming light weight, ovenable food containers.

Abstract: A polyisocyanurate coating composition, which composition comprises and is prepared by reaching 100 parts of a methylene diisocyanate, having an average functionality of less than about 2.4, with a mixture of a di or triethylene glycol and a methoxy polyethylene glycol, the reaction carried out in the presence of a trimerization catalyst, and to a polyisocyanurate-coated, rigid-foam insulation board coated with such composition.

Abstract: A process for the production of an expandable silicone resin includes reacting a substantial amount of the silanol (SiOH) groups present in the resin to form siloxane bonds and water, and heating the resin to a temperature above the resin's melting point, at which chemical reaction (condensation) of the silanol groups occur. The reaction increases the molecular weight of the resin and decreases the amount of water that must be removed during a subsequent foaming step, thereby controlling the rate and extent of foaming which can occur. The resin is solidified, pulverized and size-reduced to a powder form. The resin powder is blended with a minor amount of a particulate inert filler which is coated with a silicone resin curing catalyst and also with a minor amount of blowing agent (powder). The dry powder blend is then thermally fused for a closely-controlled, short duration, time at a temperature near the lower end of the blowing agent's gas-generating temperature range.

Abstract: A cellular foam particularly suitable for use as thermal or accoustic insulation is produced by the condensation in an acidic medium in the presence of a catalyst hardener of methyloldihydroxydiphenylmethylene ether isomers.

Abstract: Compositions that cure rapidly to produce silicone foams and protective coatings are disclosed. These compositions comprise: (A) a certain liquid copolymeric polyorganosiloxane; and (B) an amino functional silicone polymer. For example, simple mixtures of the liquid copolymeric polyorganosiloxane and a polydiorganosiloxane having aminoalkyl substituents can be mixed together to form a resilient silicone foam. If the foam compositions are further provided with certain mineral fillers, a high degree of fire resistance is attained.

Abstract: Copolyimide foams derived from a diester of 3,3',4,4'-benzophenonetetracarboxylic acid, an aromatic diamine, and a heterocyclic diamine. A molar concentration of the heterocyclic diamine approaching but not exceeding 0.42 is employed. This results in a flexible foam with a homogeneous cellular structure and a reduced compression set loss.

Abstract: A foamed article of poly-n-butyl methacrylate or a copolymer of n-butyl methacrylate and other vinyl monomer is obtained by allowing n-butyl methacrylate alone or n-butyl methacrylate in conjunction with the other vinyl monomer to stand at room temperature under a vacuum.

Abstract: High density structural ("blocking") materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

Abstract: A process for producing a high quality silicone foam by free foaming, in which a two-component addition crosslinking system is used, comprised of a component A which contains a silicone polymer having at least two double bonds per molecule, preferably vinyl groups, a complexed organo-platinum for example with butanol, fumed silica, and water, as well as further additives, if appropriate, and a component B which contains a silicone polymer having at least two double bonds per molecule, preferably vinyl groups, fumed silica, and polydimethyl hydrogen siloxane as SiH crosslinking; agent. The two components A and B are mixed, and the reaction mixture is subsequently pressurized, preferably using compressed air or nitrogen, in a storage vessel over several hours so that the gas is present in the mixture in a dissolved form.