Abstract: A polymeric composition to be used in producing foam in which the polymeric composition comprises high density polyethylene, alkenyl aromatic polymer and a resiliency modifier resin. The high density polyethylene is in an amount of from about 5 to 45 weight percent of the polymeric composition. The high density polyethylene has a z-average molecular weight, Mz, greater than about 1,000,000. The alkenyl aromatic polymer is in the amount of from about 3 to about 45 weight percent of the polymeric composition. The resiliency modifier resin is in the amount of from 10 to about 85 weight percent of the polymeric composition.

Abstract: A foamable polyester composition comprising a combination of blowing agent and mixed polymer composition comprising: a) a semi-crystalline polyester composition comprising a polycondensed branched polyester polymer, and b) an aromatic polycarbonate polymer. The foamable composition has a high extrusion melt strength, and can pulled across a die without ripping, to form a continuous thermoformable closed cell polyester sheet. The foamed sheets have a uniform, fine, and closed cell morphology; and simultaneously are less dense but have a higher impact strength than comparable closed cell polymers made in only with linear polyesters as the polyester component or without the aromatic polycarbonate.

Abstract: The present invention relates to a process for the preparation of a foamed article having a foam density of less than 180 kg/m3 and an average cell diameter of less than 1.5 mm comprising the extrusion of a molten semi-crystalline thermoplastic resin composition in the presence of a foaming agent, with the semi-crystalline thermoplastic resin composition comprising a polymeric epoxide containing at least two epoxide groups being a copolymer of a monomer mixture comprising at least one C10 to C18-olefin and at least one ethylenically unsaturated compound comprising an epoxide group. The process results in the preparation of foamed articles having a regular and homogeneous structure. Another advantage of the present invention is that it is not necessary anymore to add a compound of Group Ia, IIa, or IIIa of the Periodic Table, such as LiCl, to the extrusion process.

Abstract: An acoustical insulation foam having, either with or without elastification, an Asker C hardness of less than about 65, a density of about 5 to about 150 kg/m3, a cell size of about 0.05 to about 15 mm, an open cell content of 0 to about 100 volume percent, a thickness of about 1 to about 200 mm, and a width of about 100 to about 3000 mm; comprising; (A) one or more alkenyl aromatic polymers, (B) one or more substantially random interpolymers and (C) optionally, one or more nucleating agents and (D) optionally, one or more other additives; and (E) one or more blowing agents.

Abstract: An open-cell polystyrene foam is provided which is formed from a blend of polystyrene and an ethylene-styrene interpolymer. The ethylene-styrene interpolymer functions as a cell opening agent, and is used to control the open cell content of the resulting foam, which may contain greater than 80 percent open cells. The foam is produced by an extrusion process in which carbon dioxide is used as the preferred blowing agent. The resulting foams may be formed into beads, plank, round, sheets, etc.

Abstract: Semi-crystalline microcellular foams that include a midlevel amount of nucleating agent, and methods of their production, are provided. The microcellular foams can be produced in typical polymer processing techniques such as extrusion, injection molding and blow molding. The foams exhibit excellent mechanical properties and can be formed over a broad range of density into a number of different foam articles.

Abstract: The melt of polyvinyl aromatic polymers comprising from 10 to 45 weight % of star branched polymer prepared using a combination of thermal and tetra functional peroxide initiation has an improved melt strength permitting better foam formation for extrusion foam blown with conventional blowing agents and inert gases including CO.sub.2.

Abstract: A polymer blend foam having smooth skin and/or an open-cell content of at least 20 volume percent, a crosslinked gel content of no greater than 10 percent, a minimum cross-sectional area of at least 1000 mm.sup.2, and a density of no greater than 250 kg/m.sup.3. The blend includes (A) a substantially random interpolymer having polymerized therein (1) a vinyl or vinylidene aromatic monomer and/or a sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomer, and (2) one or more of ethylene and a C.sub.3-20 aliphatic .alpha.-olefin; and (B) an olefin polymer based on one or more of ethylene, C.sub.3-20 aliphatic .alpha.-olefins, and C.sub.3-20 aliphatic .alpha.-olefins containing polar groups. The olefin polymer (B) lacks any of the vinyl or vinylidene aromatic monomers found in (A).

Abstract: A process additive for polyolefin films and foams produces products having reduced aging time and reduced greasiness and reduced grease-like transfer as compared to glycerol monostearate (GMS). Carbon dioxide based blowing agents are suitable. The process additive comprises a fatty acid N-aliphatic alcohol amide of the general formula R-CON(R')R". R is a fatty hydrocarbon radical having from about 8 to 30 carbons. R' typically is hydrogen. R' can also be an alkyl radical of from about 1 to 6 carbons or an alkyl alcohol radical of from about 1 to 6 carbons. R" is an alkyl alcohol fragment of from about 1 to 6 carbons. The alkyl alcohol fragments can be monohydric or polyhydric. Secondary fatty monoalkanolamides in which R' is hydrogen are particularly useful, especially stearamide monoethanolamine (MEA). The benefits of the invention can be achieved and enhanced in some examples by mixing the fatty acid N-aliphatic alcohol amide with an ester of a long chain fatty acid with a polyhydric alcohol, including GMS.

Abstract: A soft foam having an Asker C hardness of less than about 65, comprising;(A) from about 30 to about 70 percent by weight (based on the combined weight of Components A and B) of one or more alkenyl aromatic polymers and wherein at least one of said alkenyl aromatic polymers has a molecular weight (M.sub.w) of from about 100,000 to about 500,000; and(B) from about 30 to about 70 percent by weight (based on the combined weight of Components A and B) of one or more substantially random interpolymers; and(C) optionally, one or more nucleating agents; and(D) optionally, one or more other additives; and(E) one or more blowing agents present in a total amount of from about 0.4 to about 5.0 gram-moles per kilogram (based on the combined weight of Components A and B).

Abstract: A formed rubber extruded product which is formed of a vulcanizate of a rubber blend comprising a sulfur-vulcanizable ethylene-propylene-type rubber (EPDM) as a starting rubber and a pyrolytic foaming agent. The vulcanizate has a specific gravity of from 0.9 to 1.0 and a surface roughness (RZD) of 14 micrometers or less. The rubber blend contains the pyrolytic foaming agent in the form of an inorganic powder-supported foaming agent. A particle diameter of the inorganic powder in the inorganic powder-supported foaming agent is approximately 9 micrometers or less, and a particle diameter of the pyrolytic foaming agent is approximately 8 micrometers or less. Further, crystalline PE is contained in an amount of from 6 to 30 parts per 100 parts of EPDM. The foamed rubber extruded product of the present invention can be produced by the extrusion at a high rate.

Abstract: The present invention relates to a polymeric compound comprising(a) 100 parts by weight of a block copolymer comprising at least two external monovinyl aromatic hydrocarbon blocks and at least one internal hydrogenated conjugated diene block, wherein the total monovinyl aromatic hydrocarbon content is from 20 to 50% by weight and the total apparent molecular weight is from 140,000 g/mol to 400,000 g/mol;(b) 50 to 250 phr of a plasticiser;(c) 10 to 100 phr of a polybutene-1 polymer having a melt index at 2.16 kg/190.degree. C. of from 0.05 to 400;(d) a blowing agent.The present invention further relates to use of the compound for the preparation of foamed compounds; to a foaming process; to a masterbatch blend; to a foamed compound; and to articles containing the foamed compound.

Abstract: An expandable resin composition comprising:(A) 100 parts by weight of HDPE (high density polyethylene) having a DSC melting point of about 127 to about 136 degrees C.; a density of 0.945 to 0.967 gram per cubic centimeter; and a melt flow rate of about 0.1 to about 10 grams per 10 minutes, and for each 100 parts by weight of component (A),(B) about 2 to about 50 parts by weight of polypropylene having a DSC melting point of at least about 130 degrees C.;(C) about 50 to about 200 parts by weight of an ethylene/alpha-olefin copolymer, prepared with a metallocene catalyst, having a DSC melting point of about 98 to about 121 degrees C.; a density of 0.900 to 0.935 gram per cubic centimeter; and a melt flow rate of about 0.5 to about 3 grams per 10 minutes;(D) about 0.1 to about 5 parts by weight of a polysiloxane-polyether block copolymer having the following formula:R.sub.3 --Si--O--R.sub.2 (SiO).sub.m --RX(SiO).sub.n --SiR.sub.

Abstract: An expandable resin composition comprising(A) HDPE (high density polyethylene);(B) a high pressure, low density homopolymer of ethylene (HP-LDPE);(C) polypropylene;(D) a polysiloxane-polyether block copolymer; and(E) a nucleating agent of azodicarbonamide and/or talc.

Abstract: Foamed articles having enhanced tensile, elastic recovery, and creep and fatigue resistance properties are prepared using a dual cure system. This system comprises a heat or radiation-activated first stage cure (which follows or coincides with foaming) followed by a moisture-activated second stage cure. Heat-activated curing systems include peroxide, sulfur, etc., and radiation-activated cure systems include electron beam, gamma-ray, etc. Moisture-activated systems include silane, sulfonyl chloride, and the like.

Abstract: A nucleator for foaming comprising a fluororesin powder comprising particles having a particle size of 0.1-0.5 .mu.m in a proportion of at least 50% by number and containing particles having a particle size of not less than 5 .mu.m in a proportion of not more than 40% by number, a foamable composition comprising this nucleator and an organic polymer, a foam made therefrom, and a production method of the foam. The nucleator of the present invention can produce a foam made from an organic polymer improved in expansion ratio, fineness of the cells, uniformity of foaming and the like by the use of an extremely small amount thereof. It is preferably used for forming an insulating foam layer of a high frequency coaxial cable.

Abstract: A process for producing structural thermoplastic foam is provided which involves gas expansion of a melted thermoplastic resin composition containing an amount of a polyolefin resin effective as a nucleating agent. The thermoplastic resin compositions provided exhibit an improved uniformity of cell structure in the resultant structural thermoplastic foam as a result of the incorporation of the polyolefin nucleating agent. The process and compositions are useful in the production of structural thermoplastic foam articles.

Abstract: A foamable polyester composition comprising a combination of blowing agent and mixed polymer composition comprising:a) a semi-crystalline polyester composition comprising a polycondensed branched polyester polymer, andb) an aromatic polycarbonate polymer.The foamable composition has a high extrusion melt strength, and can pulled across a die without ripping, to form a continuous thermoformable closed cell polyester sheet. The foamed sheets have a uniform, fine, and closed cell morphology; and simultaneously are less dense but have a higher impact strength than comparable closed cell polymers made in only with linear polyesters as the polyester component or without the aromatic polycarbonate.

Abstract: A foam comprising a blend of a low density polyethylene and an ethylene/alpha-olefin copolymer is disclosed. The ethylene/alpha-olefin copolymer is preferably LLDPE and has a density ranging from about 0.86 to about 0.94 grams/cubic centimeter and a melt flow index of greater than 10 g/10 minutes. A method for producing such foam is also disclosed.

Abstract: An open-cell polystyrene foam is provided which is formed from a blend of polystyrene and an ethylene-styrene interpolymer. The ethylene-styrene interpolymer functions as a cell opening agent, and is used to control the open cell content of the resulting foam, which may contain greater than 80 percent open cells. The foam is produced by an extrusion process in which carbon dioxide is used as the preferred blowing agent. The resulting foams may be formed into beads, plank, round, sheets, etc.

Abstract: A method of producing a substantially open-cell, expanded polystyrene sheet, comprising the steps of:forming a mixture comprising from 30 to 95% of polystyrene incorporating an aliphatic hydrocarbon with 4-6 carbon atoms, from 0 to 65% of polystyrene, and from 0.2 to 10% of a nucleating agent,mixing the mixture obtained and melting it by heating inside an extruder,bringing the mixture to a temperature of 130-150.degree. C. in the final portion of the extruder,extruding the mixture in a lower-pressure atmosphere to produce an expanded sheet, which has a low density and a high capacity to absorb aqueous liquids, particularly if a surfactant is added to the starting mixture, and which, when coupled with two films of plastics material gives rise to a laminate suitable for the production, by thermoforming, of trays for foods which may release aqueous liquids.

Abstract: The present invention relates to a foamed article comprising a modified polypropylene resin which is a graft copolymer of a polypropylene resin and an aromatic vinyl monomer and has an average number of the grafted aromatic vinyl chains of not less than 1 in one molecule of the graft copolymer and a weight average molecular weight of the grafted aromatic vinyl chains of not less than 200, and relates to a process for preparation thereof. According to the present invention, the foamed article comprising the polypropylene resin and having a high closed cell content, a high expansion ratio and good external appearance can be provided.

Abstract: A blowing agent comprising a hydrofluorocarbon having at least one hydrogen atom and containing no chlorine is used to obtain a polystyrene-based resin foam body with a high expansion rate, employing as the base polymer a resinous blend comprising polystyrene and a polymer containing oxygen, nitrogen or fluorine or a resinous blend comprising polystyrene and an oxy acid or its derivative.

Abstract: Foamed articles having a closed cell structure formed from a polymer blend comprising at least 50% by weight of a styrenic polymer and up to 50% by weight of an acrylic polymer which has an average molecular weight which is less than 90% of that of the styrenic polymer which are significantly less dense than such articles prepared from the styrenic polymer alone.

Abstract: A foam article is made by (1) irradiating a propylene polymer material selected from the group consisting of (a) a terpolymer of propylene, ethylene, and butene-1, (b) a polyolefin composition that includes (i) about 31% to about 39% of a copolymer of propylene and ethylene, and (ii) about 58% to about 72% of a terpolymer of propylene, ethylene, and butene-1, and (c) a polyolefin composition that includes (i) about 30% to about 65% of a copolymer of propylene and butene-1, and (ii) about 35% to about 70% of a copolymer of propylene and ethylene, and (2) extruding the irradiated propylene polymer material through a die in the presence of a physical expanding agent and a cell nucleating agent, whereby a structure is formed whose density is at least 10.times. less than the initial density of the propylene polymer material. The foam articles exhibit improved flexibility and low temperature toughness compared to conventional propylene polymer materials.

Abstract: A foamed cellular material which can be obtained from foamed aromatic polyester resins with a bulk density of 50 to 700 kg/m3 by heating in vacuum to temperatures which are higher than the Tg of the material and lower than its melting point. The foamed material, generally in the form of a sheet or panel, has high-level characteristics in terms of flexibility and dimensional thermostability depending on the degree of crystallinity after the vacuum treatment.

Abstract: Foamed polymeric materials exhibiting improved heat resistant properties and improved mechanical properties, as compared with known foamed styrene polymer materials, are obtained by expanding a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart enhanced heat resistant properties to the blend.

Abstract: The present invention relates to an opaque, biaxially oriented polymeric film having a thermoplastic polymer matrix material within which is located a stratum of voids. The voids are formed during orientation by a cavitating agent which is a particle of a cyclic olefinic copolymer. The solid particle is phase-distinct and incompatible with the matrix material.

Abstract: The present invention pertains to improved alkenyl aromatic polymer foams (and processes for their preparation) having increased heat distortion temperature and improved dimensional stability while maintaining good tensile/tear, creep and environmental dimensional change properties.The closed cell low density alkenyl aromatic polymer foams exhibit increased heat distortion temperature, when substantially random interpolymers of about 21 to about 65 mol % styrene are blended in. When these same alkenyl aromatic polymer foams are made without these interpolymers, the heat distortion temperature is not improved.

Abstract: A foam rubber composition and a method for making same which is foamable to a high degree and a molded product made from the foam rubber composition wherein the compositions has: (A) a low-molecular Ethylene-propylene-5-ethylidene-2-norbornene terpolymer having a Mooney viscosity (ML.sub.1+4 at 100.degree. C.) of 20 to 40, an ethylene/propylene ratio by weight of 65/35 to 50/50, an iodine value of 20 to 30, and a Q value (Mw/Mn) not exceeding 3 as determined by gel permeation chromatography; (B) a high-molecular ethylene-propylene-5-ethylidene-2-norbornene terpolymer having a Mooney viscosity (ML.sub.1+4 at 100.degree. C.) of 100 to 300, an ethylene/propylene ratio by weight of 65/35 to 50/50, an iodine value of 20 to 30 and a Q value (Mw/Mn) of 6 to 10; (C) a vulcanizing system agent containing sulfur as a vulcanizer, and zinc carbamate and sulfenamide as accelerators; and (D) a foaming agent containing N, N'-dinitrosopentamethylenetetramine and urea.

Abstract: A foamable polyester composition comprising a combination of blowing agent and mixed polymer composition comprising:a) a semi-crystalline polyester composition comprising a polycondensed branched polyester polymer, andb) an aromatic polycarbonate polymer.The foamable composition has a high extrusion melt strength, and can pulled across a die without ripping, to form a continuous thermoformable closed cell polyester sheet. The foamed sheets have a uniform, fine, and closed cell morphology; and simultaneously are less dense but have a higher impact strength than comparable closed cell polymers made in only with linear polyesters as the polyester component or without the aromatic polycarbonate.

Abstract: Disclosed herein is an improvement in microcellular or supermicrocellular polymer extrusion systems. Both conventional and microcellular systems employ an extruder which plasticates polymer pellets into a polymer melt; a gas metering system, whereby a gas is injected directly in the polymer melt flow in the extruder; a mixing and homogenizing section of the extruder, which creates a single-phase solution of the polymer and the gas; and a nucleation device at the outlet end of the extruder. In this invention, the improvement to the conventional system comprises the nucleation means attached to said extruder which is a gear pump acting as a throttle rather than a pump. With this improvement, the discharge pressure is dictated by die resistance and flow rate as delivered by the gear throttle, and the pressure drop of the polymer/gas single-phase solution is nearly instantaneous.

Abstract: This invention pertains to a composition and a process for preparing a closed cell alkenyl aromatic polymer foam having enlarged cell size, comprising one or more alkenyl aromatic polymers, one or more substantially random interpolymers, one or more blowing agents having zero ozone depletion potential and optionally one or more co-blowing agents, and optionally, one or more nucleating agents and optionally, one or more other additives.This combination allows the manufacture of closed cell, low density alkenyl aromatic polymer foams of enlarged cell size, when blowing agents of relatively high nucleation potential are employed. When such blowing agents are used with alkenyl aromatic polymers in the absence of the substantially random interpolymers, small cell foams result.

Abstract: The present invention provides a process for producing thermoplastic foam, including:(a) melting a thermoplastic polymer to produce a polymer melt;(b) introducing a carbon dioxide blowing agent into the polymer melt;(c) adding to the polymer melt one or more additives selected from the group consisting of(1) polysiloxane, and(2) mineral oil; and(d) extruding and foaming the melted polymer melt, blowing agent, and one or more additives to produce thermoplastic foam.The resultant thermoplastic foam can be thermoformed into various foamed articles, such as foam packaging trays. The quality of foams made from a carbon dioxide blowing agent, and particularly 100% carbon dioxide, has been found to be substantially improved by adding one or more of the foregoing additives, i.e., polysiloxane, mineral oil and, optionally, polyolefin to the polymer melt during the extrusion and foaming process.

Abstract: Hot-curing, foamable reactive compositions based on natural and/or synthetic rubbers containing olefinic double bonds, vulcanizing agents and blowing agents with a high percentage content of sulfur give foamed rubber compositions exhibiting high structural strength and high volume expansion. These compositions are suitable as multifunctional filling materials for hollow structures or hollow profiles in vehicle or machine construction. At one and the same time, they perform a sealing function, damp acoustic vibration and stiffen the hollow structures to a considerable extent.

Abstract: A foamed article having a closed cell structure formed from: (i) a polymer blend comprising at least 80% by weight of a styrenic polymer and up to 20% by weight of an acrylic polymer; and (ii) gaseous carbon dioxide blowing agent.

Abstract: Foamable organosiloxane compositions which yield, upon cure, silicone foams having low density and decreased friability, comprising a siloxane base polymer having an average of at least two hydroxyl groups per molecule, a silicon-containing crosslinker for the siloxane base polymer, wherein the crosslinker contains at least two --SiH groups per molecule; a platinum group catalyst; a silicone resin copolymer; and optionally, a blowing agent; and silicone foams prepared therefrom. A method of weather-stripping a door or window using a silicone foam so prepared.

Abstract: Disclosed is a method of enhancing open cell formation in making extruded alkenyl aromatic polymer foams of about 30 percent or more open cell content. Open cell formation is enhanced by incorporating into the foam an ethylene copolymer having a Vicat softening point of about 85.degree. C. or less. The ethylene copolymer is incorporated at from about 0.1 to about 7 percent based upon the weight of the alkenyl aromatic polymer material comprising the foam.

Abstract: An extruded filtration material which is degradable and comprises either a plastics material or an inorganic material having a melting point above the operating temperature, a polysaccharide expansion medium, a binder and water. These ingredients are fed to an extruder and subjected to an extrusion process which involves a pressure reduction, upon extrusion from the exit die, of up to about 70 bars so that swelling of the extrudate occurs to give a cellular structure. When exposed to the natural weather conditions, tobacco smoke filter elements comprising such material degrade without leaving a fused amalgamation of plastics or inorganic material.

Abstract: The novel blend comprises:(A) from 1 to 99% by weight of at least one thermotropic-liquid-crystalline polyester and/or polyesteramide and(B) from 1 to 99% by weight of at least one sulfoxide group-containing polymer,in each case based on the total weight .SIGMA.?(A)+(B)!. Component (B) is a linear and/or branched polymer having a mean molecular weight M.sub.w in the range from 4,000 to 200,000 comprising recurring units of the formula ?--F--S).sub.c --(F--SO).sub.d --!, where F, independently of one another, are simple or para-, meta- or ortho-linked arylene systems having 6 to 18 carbon atoms, preferably phenylene, naphthylene or biphenylene, where the sum c+d is 1, with the proviso that d is always .gtoreq.0.70. Component (A) is a thermotropic liquid-crystalline polymer having a mean molecular weight M.sub.w in the range from 10,000 to 200,000 g/mol and a transition temperature of >250.degree. C., and/or an amorphous thermotropic liquid-crystalline polymer having a mean molecular weight M.sub.

Abstract: High elasticity foams can be prepared from a reprocessable blend of a thermoplastic vulcanizate and an elastic thermoplastic polymer. These foams can be mechanically foamed with water and can have elongations to break in excess of 250 percent. They also have recovery of that elongation also known as low permanent set.

Abstract: New cross-linked polymeric foam compositions, and methods for making the same, are provided. The new compositions utilize novel cross-linked polyolefin copolymers and show improvements in strength, toughness, flexibility, heat resistance and heat-sealing temperature ranges as compared to conventional low density polyethylene compositions. The new compositions also show processing improvements over linear low density polyethylene. The novel polyolefins, which are essentially linear, comprise ethylene polymerized with at least one alpha-unsaturated C3 to C20 olefinic comonomer, and optionally at least one C3 to C20 polyene, and exhibit, in an uncross-linked sense, a resin density in the range of about 0.86 g/cm3 to about 0.96 g/cm3, a melt index in the range of about 0.5 dg/min to about 100 dg/min, a molecular weight distribution in the range of from about 1.5 to about 3.5, and a composition distribution breadth index greater than about 45 percent.

Abstract: Fine-celled polyolefin foams of high dimensional stability at elevated temperatures and high stiffness, with foam densities ranging from 10 to 600 kg/m.sup.3, consisting of mixtures of polypropylenes and polyolefins, which were reacted with bifunctional, unsaturated monomers and/or hydrolyzable, ethylenically unsaturated organosilane compounds in the presence of thermally decomposing free radical-forming agents in two reactive process steps and subsequently foamed. The fine-celled polyolefin foams are suitable for use in the packaging sector, preferably for packaging foods, for external and internal parts of motor vehicles and for components of electric and electronic equipment.

Abstract: A process for forming a foamed article having a closed cell structure without the need to use a halogenated blowing agent. In the process, a polymer blend comprising at least 50% by weight of a styrenic polymer and up to 50% by weight of an acrylic polymer which has an average molecular weight which is less than 90% of that of the styrenic polymer and a hydrocarbon blowing agent are supplied to a heated extruder where the blend is formed and the blowing agent incorporated to form a molten mixture from which the foamed article is formed on release from the extruder.

Abstract: Foamed polymeric materials exhibiting improved heat resistant properties and improved mechanical properties, as compared with known foamed styrene polymer materials, are obtained by expanding a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart enhanced heat resistant properties to the blend.

Abstract: The present invention aims to improve soundproof and heat insulating properties of a foamed plastic by reducing internal cells pressure inside foamed resins. A base polymer such as a polyester-based polyol and a volatile foaming agent having an conjugate unsaturated group (i. e., conjugate double carbon bonds and/or triple carbon bonds) such as chloroprene (bp. 51.degree. C.) and calcium stearate were blended and then mixed with a hardening agent such as hexamethylene diisocyanate. The volatile foaming agent existing in open cells of the foamed plastic sealed in the Al laminated film and between the film and the foamed plastic, i.e., gap, possesses an unsaturated group, such as isoprene. Thus polymerization may occur by irradiating with electron rays, and the inside of the foams and the gap region may be reduced in pressure while the bag of the laminated film retains its shape.

Abstract: Disclosed is an extruded, open-cell microcellular alkenyl aromatic polymer foam useful in insulating applications. The foam has an open cell content of about 70 percent or more. The foam has an average cell size of about 70 micrometers or less. The foam is particularly useful in evacuated or vacuum insulation panels. Further disclosed is a process for making the open-cell foam. Further disclosed is a fabricated foam article.

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: Disclosed is an extruded, open-cell microcellular alkenyl aromatic polymer foam useful in insulating applications. The foam has an open cell content of about 70 percent or more. The foam has an average cell size of about 70 micrometers or less. The foam is particularly useful in evacuated or vacuum insulation panels. Further disclosed is a process for making the open-cell foam. Further disclosed is a fabricated foam article.

Abstract: Disclosed is an evacuated and unevacuated microcellular foam containing an infrared attenuating agent (IAA). The evacuated foam has an average cell size of about 70 micrometers or less. The unevacuated foam has an average cell size of 1.0 micrometers or less. The IAA provide a greater proportional reduction in foam thermal conductivity in these foams than in foams of larger cell size. Further disclosed is a method of using the foams.