Abstract: The present invention relates to processes of producing transparent foamed plastics, particularly foamed acrylate and methacrylate materials, in the form of e.g. panels, molded articles, or as cores for laminate bodies. Solid beads of transparent polymer material and containing a blowing agent are mixed with a reaction resin, softened by heating or swelling, and expanded to large pore size. During the blowing the beads may be displaced relative to one another. Subsequently the reaction resin is completely polymerized. The so obtained foamed plastics panels, which have large closed cells with contiguous faces and a smooth, non-porous surface, are particularly useful as insulating and building material exhibiting good transparency and protection against loss of heat, especially for greenhouses.

Abstract: A process is provided for forming a plurality of objects simultaneously from a plurality of superimposed sheets of deformable and fusible material comprising the steps of heating said plurality of superimposed sheets until said material in said sheets reaches a temperature sufficient to allow plastic deformation while maintaining time, temperature and pressure conditions at the contiguous faces thereof below those causing fusion of said material and forming said plurality of superimposed sheets simultaneously.

Abstract: A pull strap handle meeting all the standards of the automotive industry is formed economically with molding operations. The handle is formed with a strip 15 of strong resilient material with high tensile strength that serves as a support element. Support element 15 is enclosed within a molded cover having a firm outer side 17 and a soft inner side 18. Soft side 18 is molded of foamed resin material directly onto support element 15 to form a secure bond. Firm side 17 can be molded in a single operation with soft side 18 or can be molded separately, attached to support element 15, and located in a cavity mold that forms soft side 18. The cover can also be molded to support element 15 within a cavity mold that forms both cover sides 17 and 18 or the cover can be extruded onto support element 15 in a continuous operation.

Abstract: A method of forming synthetic articles of polyester resin by resin transfer molding techniques or the like comprising combining a set of reactants including a major base mass of polyester resin in fluid form, at least one polyester cure accelerator, a selected quantity of isocyanate, a surfactant and at least one promoter. The isocyanate is added in sufficient quantity to react with at least one other component in the mixture to produce quantities of carbon dioxide throughout the mixture. The resultant mixture is transferred into a closed mold prior to substantial reaction. The promoter is allowed to react exothermically with at least one other component of the mixture to trigger the isocyanate to react to evolve carbon dioxide gas to generate pressure to fill the mold. Thereafter a curing reaction between the cure accelerator and the polyester occurs to cure and solidify the expanded resin to produce an expanded article.

Abstract: The addition of a small amount of a halogen compound, e.g. chloroethyl phosphate, in a process producing elastomeric polyurethane RIM parts using tertiary amines as the chief catalyst component results in scavenging the residual amines after the part has been cured by annealing. The parts from such a process can be coated with a wide variety of enamels having a high solids content and completely cured to result in a higher degree of adhesive between the coating and the part's surface than those parts from a process without the use of such a halogen.

Abstract: A process of producing a fibre-reinforced shaped article comprising extruding a composition comprising a settable fluid as a carrier for fibres at least 5 mm in length through a die so that relaxation of the fibres causes the extrudate to expand to form an open fibrous structure with randomly dispersed fibres as the extrudate leaves the die characterized in that the porous extrudate is compressed while the carrier is in a fluid condition into a shaped article. The process enables moulded articles to be formed having a random distribution of fibres the majority of which are at least 5 mm long.

Abstract: The invention relates to a process for the continuous manufacture of foamed sheets of thermoplastic material having an extreme width to thickness ratio, small thickness tolerance, a uniform cell structure and, over the whole cross section on both sides of the sheet a thin, non-foamed outer skin. The plastic, which already contains the foaming agent is, on emerging from a wide-slit nozzle, allowed to foam freely without any restriction and cool. The sheet or strip formed in this manner is then heated locally at the surface and calibrated to final dimension.

Abstract: A method for manufacturing a heat insulating pipe having a foamed insulating layer around the outer surface of said pipe. The foamed insulating layer has an expansion ratio of at least 4. It has three integral sub-layers, said sub-layers including a cellular middle foamed sub-layer which is integral with a cellular inner foamed sub-layer and a cellular outer foamed sub-layer, said inner and outer sub-layer being on opposite sides of said middle sub-layer, said cellular inner foamed sub-layer being the innermost sub-layer with respect to said pipe and surrounding the outer surface of said pipe. The cells of said inner and outer sub-layers are smaller than the cells of said middle cellular sub-layer, the ratio .mu..sub.1 /.mu..sub.2 of the cell dimensions of said cellular middle sub-layer are between 0.3 and 0.9, wherein .mu..sub.1 is the average cell dimension measured in the radial direction of said pipe and .mu..sub.2 is the average cell dimension measured in the axial direction of said pipe.

Abstract: This apparatus is used to improve the heat distribution on the cavity surface in foam molding dies where a smooth finish on the resin filled foam molded plastic product manufactured by an injection molding process is desired. This invention improves the method for heating the mold cavity using a condensing vapor in a molding die by a channel and slit type orifice means in the mold around a portion of the periphery of the part to be molded. Another channel and slit type orifice means around the remaining periphery is included in the die for removing the condensing vapor or condensate from the mold cavity. During the heating process when condensing vapor is introduced into the mold the sprue opening to the extruder is sealed by a valve means to prevent condensate from collecting therein.

Abstract: The invention comprises a method to quickly heat a mold cavity surface or portions thereof just prior to the injection of a foamable plastic resin. The apparatus comprises one or more thin metal surface sheets or bands of high electrical resistivity in the mold cavity covering those portions of the mold where a smooth surface finish on the product is desired. In an alternative form the surface sheets may be plated or sprayed metal of high resistivity on a layer of thin electrically non-conducting plastic in turn adhered to the mold cavity surface.The thin metal surface sheet is resistance heated approximately 300.degree. F. in a few seconds or less by a low voltage high current source of electric power just prior to the injection of the foamable plastic. The high current passing through the metal of high resistivity causes conversion of electrical energy into sensible heat very quickly to accomplish quick heating of the mold cavity surface sheet.

Abstract: A sewer pipe, transport pipeline, or other circumferentially enclosed passageway is lined by inserting into and along it a flexible tubular material of given diameter, with its corresponding circumference being less than the inside perimeter of the passageway. The tubular material is a laminate having a dimensionally stable skin layer facing the interior of the passageway and a contiguous layer of a composition foamable to form an expanded cellular structure. After insertion of the tubular material the contiguous layer is foamed to expand cellularly so as to fill the space between the inner skin and the inside wall of the passageway and to solidify in place. The tubular material may have an expansible outer skin layer also.

Abstract: The thermally insulated conduit includes an internal pipe, an external pipe, and an insulating foam which fills the interspace formed between these pipes. An electric grid, consisting of a wire heater, extends through the tubular space and is attached to the outer periphery of the internal pipe. The insulating foam used is made from a base of epoxy resins which are polymerized and hardened by an exothermic chemical reaction. The electric grid is used to heat the fluid contained in the internal pipe when the conduit is operated.

Abstract: A deformable and durable polyurethane foam molding is made from the reaction product of a polyether polyol component and a polyisocyanate component. The polyether polyol component is a polyether having at least two hydroxyl groups, a molecular weight of from 400 to 10,000 and at least 10 wt. % hydroxyl groups which are primary hydroxyl groups. The polyisocyanate component is a mixture of from 60-90 wt. % 4,4'-diphenyl methane diisocyanate and from 3-30 wt. % 2,4'-diphenyl methane diisocyanate. Such reaction mixture is prepared in each of at least two mixing heads. The index of reaction mixture is different from that in the other mixing head. The mixture is then introduced into associated zones of a mold cavity where the mixture is allowed to foam. The molding is subsequently removed from the mold cavity. These polyurethane foam moldings are particularly useful in making seat cushions.

Abstract: A strong foam core structural member having an integral skin and a method of forming the foam core structure using conventional tooling, such as a clamshell mold. The method includes injecting a fluid foamable resin reaction mixture under pressure in a mold between a pair of pervious, absorbant, flexible sheets, preferably each including a nonresilient open mesh skrim. The sheets are thus expanded against the mold faces by the foaming reaction mixture, which saturates the sheets and forms a smooth skin integral with the foam core. The pervious sheets permit entrapped gasses to escape, forming a smooth integral skin on the foam core, which substantially improves the strength of the structure. The structure may also be strengthened by adding perforated reinforcement plates and injecting the fluid resin reaction mixture through and around the plates. The reinforcement plates thus become integral with the foam core.

Abstract: This invention relates to a process for the production of optionally cellular, elastic, shaped articles having an impervious surface layer of polyurethane-polyurea elastomers by reacting a reaction mixture of organic polyisocyanate, ethylene oxide-tipped polyoxyalkylene polyols, propylene oxide-tipped polyoxyalkylene polyols, catalysts, amine chain extenders and optionally surfactants and blowing agents by the reaction injection molding (RIM) technique.

Abstract: The invention relates to a method of moulding a tire for a wheel rim by means of a mould having mould parts, said mould parts being movable between a closed working position in which they enclose a mould cavity with the shape of the tire and an open position in which said mould parts are spaced apart, wherein in the open position of the mould parts a hollow tire core is positioned in the mould cavity while being receivable with respect to said parts, wherein the mould parts are moved into the working position, in which a residual cavity not occupied by the tire core is left free in the mould cavity, said residual cavity. Preferably the tire core is arranged on the wheel rim before being positioned with respect to the mould parts. The invention also provides a device for moulding a tire and a tire obtained with the aid of the method and device.

Abstract: A method for making closures resembling natural cork for sealing liquid product containers is described. A strand of expandable plastic material is injected into each mold cavity and is permitted to collect in that cavity in randomly oriented groups of coils which expand to fill the cavity and coalesce to create randomly oriented grain lines on the surface of the closure resembling the appearance of natural cork. Also described are methods of molding the closures which preclude the formation of leakage channels on the closure surface and preferred blends of plastic resins and pigment particles used to achieve the cork-like appearance.

Abstract: A process for producing a highly expanded polyolefin insulated cable comprising the steps of feeding a compound of polyolefin, nucleating agent and volatile liquid to an extruder, heat extruding said compound through said extruder onto an inner conductor passing through said extruder to cover the outer periphery of said inner conductor thereby forming an insulation layer of highly expanded polyolefin foam having a foaming ratio in excess of 2.5 times (60% expansion degree) tightly adhered to said inner conductor.

Abstract: A molded object having a sponge-like interior surrounded by a skin, molding composition from which it is produced, and the method for producing the article. Copolymers of vinyl-substituted aromatic compounds containing from 8-18 carbon atoms copolymerized with conjugated diene having from 4-12 carbon atoms and polymer chosen from among solid resinous polymers of vinyl-substituted aromatic compounds present in amounts ranging from about 10 to about 75 parts by weight per 100 parts by weight of the copolymer and solid resinous copolymers of ethylene present in an amount of about 5 to about 50 parts by weight per 100 parts by weight of the copolymer are blended with a sufficient amount of polarizing agent to achieve rapid heating through response to microwave treatment, blowing agent in an amount sufficient to provide a sponge-like, rubbery porosity to an article molded therefrom, and, optionally, cellular control agent.

Abstract: Polymer foam is extruded as a tube or sheet into a cooling liquid which is maintained at a temperature up to about 85.degree. C. Either one or both surfaces of the polymer are cooled as the extrudate emerging from the die orifice passes through the liquid. Styrenic polymer foam extrudate produced by such a method exhibits excellent puncture resistance and tensile properties.

Abstract: A scrap-free, substantially solid phase, relatively low temperature economical process for rapidly making plastic articles from resinous powders wherein the resultant articles can comprise various polymers including oriented polymers; polymers with a high practical heat distortion temperature; expanded polymers; ultra high molecular weight polymers; blended structures of two or more materials; or multilayered structures. The resinous powders are initially compressed into briquettes, which briquettes are heated to a temperature in the range from about the alpha transition temperature to less than the melting point or melt temperature of the polymer therein to both somewhat soften and sinter the briquettes. The sintered briquettes are forged under conditions which permit substantial plug flow deformation into preforms whereby fusion of the sintered resin powder particles occurs.

Abstract: A hand grip for a hand-held implement, e.g., a golf club, that consists of a rigid cap and a one-piece flexible foam tubular sleeve. The cap is structured to cooperate with the implement's handle shaft for locating and retaining the grip on that shaft, and for protecting the end of the shaft and the outer end of the foam sleeve. The one-piece flexible foam sleeve, preferably with an outer skin thereon to resist abrasion, provides a cushioned grip to the user. A novel method is also provided by which the rigid cap and foam sleeve grip are fabricated.

Abstract: This invention relates to a mold for molding prefoamed material of thermoplastic synthetic resin, in which the foamed product is provided with a smoothened superficial skin layer on the overall surface thereof, a beautiful external appearance and a remarkable strength. The mold according to this invention consists of a pair of molds each of which is provided with an internal wall facing to a cavity and an external wall not facing to the cavity, and either one of or each of which is provided with at least one heating chamber including a steam inlet and a steam outlet both of which are mounted in the external wall. And either one of or each of the two molds is provided with a plurality of steam passages and a surface-heating chamber independent thereof both of which are mounted in the internal wall.

Abstract: A method for the continuous fabrication of blankets or sheets of expanded phenolic resin displaying a hard skin on each of their sides, according to which a mixture, comprising in particular a resole resin, a blowing agent and a hardening catalyst is placed on an essentially flat surface of a moving element, is brought to foam and is conformed between two parallel surfaces entrained in the same direction, the lower surface being situated in the same plane as the surface of the moving component, characterized in that, in a first stage, the mixture is brought into free air towards the conformation surfaces by being submitted to a heating so as to have it expand and then the expanded mass is conformed by exerting a pressure on its free side, at the moment of entry between the conformation surfaces, and the hardening of the resin is completed while maintaining the pressure and the heating.

Abstract: A resilient synthetic resin toilet seat which includes a preformed stiffening portion having an internal foamed core. The core is enveloped in an unfoamed self-skin. A cushioning portion is molded thereon and has an internal foamed core enveloped in a tough but resilient self-skin unitarily extending from the top and sides of said stiffening portion. A resilient synthetic resin toilet seat lid having an internal foamed core enveloped in an unfoamed skin, a method of making the seat and lid by molding, as well as molds for use in such molding, are also disclosed.

Abstract: A molding apparatus in which a slider is slidable in an inclined channel into which a passage opens at one side for communication with a mold cavity while a pair of passages open at the opposite side for communication with a plasticating (worm) cylinder and a further cylinder provided with a plunger or piston. The slider has a U-shaped passage, the arms of which are positioned to interconnect both of the passages on the other side of the channel in a position of the slider in which the passage to the mold is blocked but which connects only the accumulating cylinder passage through the bight of the U-shaped passage to the mold in another position of the slider. A check valve is provided in the passage of the worm cylinder.

Abstract: The invention relates to a method of producing molded bodies of expanded plastic having a predetermined density, based on a starting material in granulate form to which a blowing agent and optionally a cross-linking agent have been added, said starting material being introduced into an injection molding machine/press in which it is heated and injected/pressed into a mold. In order to obtain an efficient production process without loss of raw material and a product whose density can be determined in advance, the material in the injection molding machine/press is heated to a temperature which is below the temperature required to initiate the reaction of the blowing agent/cross-linking agent, and the blank thus formed is subsequently transferred to an expansion mold having the shape of the desired final product, but larger, than the blank. The blank is caused to expand in the expansion mold and final expansion takes place outside the expansion mold.

Abstract: An improved article made of foamed glass or similar materials and method of manufacture is disclosed. Thus, a construction panel may be formed to bear weight, withstand weather and take reasonable impact and abuse, because of a tempered outer skin supported inside by a skeletal network of solid poreless material formed about low density pockets of substantially constant size and frequency.These panels are made by continuous pulling of the panels through a heat controlled mold in contact with the surface skin from a continuously fed molten mass into which is injected from the bottom size and frequency controlled foaming agents or gaseous bubbles which rise in the molten mass to a position where they are frozen in place.

Abstract: Disposable contraceptive intravaginal cervical barriers of one, two, three, four, or five layers in the form of standard pessaries with at least one layer impervious to the passage of sperm, with a medicament such as spermicide, germicide, or an abortion inducing agent either impregnated into a foam plastic layer or in the form of a layer of gel or powder, said medicament being activatable upon contact with an aqueous solution.Methods of producing disposable contraceptive barriers either as a wet foam plastic method wherein medicament is added to liquid foam and the resulting mixture is formed in a mold with any subsequent layers then added, or as a dry foam plastic method wherein layers including a layer of medicament in the form of a gel or a powder are superposed in sequence and formed in a die.

Abstract: A refrigerator cabinet having an outer shell with an opening at the front thereof, an inner liner within and spaced from the shell and bonded thereto by a body of foamed plastic insulating material. A rigid foam member is located in the space between the shell and liner between the insulating material and the outer shell opening. The rigid foam member has a passage for venting air from the insulation space during foaming of the insulation material and that passage is undulated sufficiently to prevent the foam insulation material from passing therethrough.

Abstract: The instant invention is directed to a process for filling a cavity with a flowable reaction mixture through an inlet opening located at the bottom of the cavity. The process broadly comprises injecting a relatively small amount of reaction mixture into the cavity to cover the inlet opening with reaction mixture. The injection process is then briefly interrupted. Thereafter, the remaining amount of reaction mixture is injected into the cavity. The invention also relates to apparatus useful in performing the above-described process.

Abstract: Asymmetric reverse osmosis membranes are made from synthetic aromatic polyimides having a relatively high predominance of polar groups in the polymer backbone. A polar/non-polar group ratio of from 2:2 to 2:7 per imidized nitrogen link is required. Such membranes can be fabricated using conventional casting equipment by providing a solution of the polyimide in a good solvent and a poor solvent, the poor solvent being compatible with solution components at poor solvent/good solvent ratios of at least 1:1 up to about 7:1, casting a film of such solution, and partially evaporating the exposed surface of the cast film for 100.+-.30 seconds prior to gelation.

Abstract: Low density, lightweight foam articles may be provided with certain portions or regions thereof, that are reinforced, having higher density and strength, obtained by compression of the foam in these locations, during or after formation of the foam. Such locations may be made sufficiently strong and dense to allow the article to be attached in place by fastening means, imbedded therein. The increase in density can be as much as from 5 pcf to 10 pcf or higher, depending upon the particular application.Many foam materials, capable of being molded, extruded, or otherwise shaped to a predetermined configuration, may be made with this combination of high and low density, including foams of styrenic polymer or copolymer compositions, urethanes, vinyls, and even non-thermoplastic based materials, such as phenolic foams.

Abstract: A projection screen is disclosed having a surface formed by a plurality of irregularly distributed microstructural elements shaped like the outer surface of contiguous bubbles. Also disclosed is a method for making such projection screens.

Abstract: A process for preparing an innersole for footwear by means of molding and curing. The molding and curing is conducted under pressure in a silicone rubber mold by means of electromagnetic radiation. By means of this process, a composite board is fused to a polymeric base to form the innersole.

Abstract: The invention provides means for producing a moulded plastics ball having the appearance of a conventional ball with a continuous curved seam. In order to make the moulding seam (parting-line) as inconspicuous as possible, the invention provides a mould assembly comprising two mould members, having mutually confronting surfaces each surrounding a part-cavity, a generally spherical mould cavity being defined when the confronting surfaces are in contact with one another, lip portions of said surface defining a continuous parting line around a diametral zone of the cavity, said parting line having four portions, comprising two substantially S-shaped portions with two at least substantially straight-line portions, said portions being arranged alternately around the diametral cavity zone, each portion of the line meeting its adjacent portion to include an angle of not substantially less than a right-angle.

Abstract: Injection moldings have excellent surface gloss and freedom from sink marks are obtained using a pressurized mold and molding composition containing a volatile fluid foaming agent, a thermally decomposable foaming agent and a finely divided nucleating agent.

Abstract: A method for the fabrication of high density smooth walled composite members laminated of resin impregnated fibers, and characterized by hydraulic pressure applied by a smooth surfaced core member comprised of noninterconnected cells subjected to heat and expanded thereby in opposition to a complementary mold with a lay-up therebetween simultaneously cured to establish a wall or skin of the product part formed thereby.

Abstract: A polyolefin filter for tobacco products and the like was prepared. The extruded element is an open-cell foamed polyethylene or polypropylene having a TPM filtration efficiency greater than 20%. The filter rod can be made by extruding polyethylene containing less than 0.2 moles of a volatile blowing agent per 100 grams of resin at a melt temperature between 130.degree. C. and 150.degree. C., the temperature of the die being between 120.degree. C. and 136.degree. C. Higher melt temperature and die temperature are required for polypropylenes.

Abstract: Expandable thermoplastic polymer beads are introduced into a tank and are agitated therein in a heated moisture-free condition. The beads are pressurized within the tank with a hot gaseous medium to soften them and are then subjected within the tank to a selected degree of vacuum to expand the beads or particles. The vacuum is removed and atmospheric pressure is re-established in the tank. The expanded hot moisture-free particles are introduced into a mold where they are fused into an integral mass, followed by cooling of the fused mass within the mold to form an outer skin on the mass. The fused mass is ejected from the mold.

Abstract: The process for producing a surface covering having a randomly embossed wear surface which comprises incorporating a blowing agent into a resinous composition, forming the resinous composition into a layer, heating to partially fuse the layer, printing a design on the surface of the layer, randomly distributing flakes of resinous composition containing an inhibitor for the blowing agent onto the printed surface of the layer, applying a clear wear layer thereto and heating the assembly to the decomposition temperature of the blowing agent.

Abstract: The densified area commonly formed during the manufacture of blocks of pliable polyurethane foam on a web of continuous material in a foaming tunnel is eliminated by controlled heating of the conveyor belt in the tunnel to a range between the densification temperature and the cracking temperature of the foam during the reaction period. An improved apparatus for this purpose comprises an enclosed, insulated housing and means for heating the conveyor belt such as hot air, infrared radiation, steam coils or electrical resistors. A preferred embodiment comprises heating the bottom of the foam block after it emerges from the foaming tunnel to a temperature considerably higher than that in the foaming tunnel. This eliminates completely any need for trimming off irregularities after removal of the web of continuous material.

Abstract: A permselective membrane comprising a thin permselective film of a polymeric material, said polymeric material being prepared by cross-linking a polyaddition product between a polyepoxy compound and a polyamino compound having at least two amino groups capable of reacting with epoxy groups with a polyfunctional compound selected from the group consisting of aromatic, heterocyclic and alicyclic compounds containing at least two functional groups selected from acid halide, sulfonyl halide, isocyanate and acid anhydride groups; and a process for producing the same. The permselective membrane of this invention is especially useful for desalination of saline or brackish water by reverse osmosis.

Abstract: A composite fiber or filament comprising a core or substrate coated with a cellular foam, and an outer circumference characterized by a substantially continuous, microcellular breathable and abrasion-resistant aspect.

Abstract: Mold, particularly for rigid polyurethane foam articles having finished textured surfaces on all sides thereof comprising a female mold having a recess into which the unreacted and unblown resin system is deposited and a cover for closing the mold together with a release sheet structure disposed therebetween exhibiting sufficient gas porosity to enable complete venting of air displaced by the rising foam in the production of a finished surface thereat and method of molding therewith.

Abstract: A process is disclosed for molding a foamed thermoplastic article characterized by a foamed core, a non-foamed exterior shell and a surface that reproducibly and faithfully replicates a predetermined portion of the inner surface of the mold in which the article is made, wherein a foamable mixture comprising molten thermoplastic material and blowing agent is introduced through a nozzle into a mold cavity defined by said inner surface of said mold and expands and is rigidified while in said mold cavity.

Abstract: A method for the continuous fabrication of blankets or sheets of expanded phenolic resin displaying a hard skin on each of their sides, according to which a mixture, comprising in particular a resole resin, a blowing agent and a hardening catalyst is placed on an essentially flat surface of a moving conveyor, is completely expanded, and is conformed eventually between two parallel surfaces entrained in the same direction, the second surface being located above and substantially parallel to and able to move at the same speed as the moving surface, characterized in that, in a first stage, after having been distributed at the surrounding temperature and in the liquid state along the whole width of the surface of the transport component, in such a way so as to comprise a blanket of expandable liquid mixture essentially uniform in thickness, the expandable mixture is conveyed in the open air towards the conformation surfaces while being submitted to a heating so that it expands, the degree of heating and the lengt

Abstract: A thermally and dimensionally stable structural foam plastic product having a cellular core and an integral solid skin on the surface thereof. The structural foam product is produced by injection molding and comprises a thermoplastic resin and from 1 to 30% by volume of flake mica as a filler.

Abstract: The pore size distribution of a microporous separation medium, such as a membrane or gel, is modified so as to provide it with a sharp upper cut-off of preselected molecular size. The modification is effected by first filling the pores of the separation medium with a volatile liquid, and then evaporating a controlled amount of the volatile liquid to form voids at the entrances to the pores. A concentrated solution of a cross-linkable or polymerizable pore-blocking agent, such as a protein, enzyme or polymeric material, is then applied to the surface of the separation medium. The pore-blocking agent is a material which is insoluble in the volatile liquid and whose molecular size distribution has a lower limit corresponding to the preselected molecular size, whereby the pore-blocking agent selectively enters only those pores larger than the preselected size and remains in the voids at the entrances to the pores.

Abstract: A method is disclosed comprising in-mold coating a structural foam part made from a thermoplastic aromatic polycarbonate resin or a thermoplastic ABS polymer resin with a thermosetting in-mold coating composition at a pressure of from about 25 to 50 p.s.i. and at a temperature not in excess of about 200.degree. F. for from about 1 to 10 minutes, preferably for from about 1 to 3 minutes, to provide hard, smooth and adherent coatings, said thermosetting in-mold coating composition comprising an ethylenically unsaturated polyester resin and an ethylenically unsaturated monomer(s) catalyzed with an organic perioxide initiator including an accelerator for the initiator.