Abstract: An apparatus for mixing and dispensing two or more reactive liquids in a homogeneous stream. The device includes a mixing chamber with two or more inlets for introducing separate liquid components into the chamber, a recycle port associated with each inlet for directing unmixed components back to their source, and an outlet for dispensing mixed liquid components from the chamber. Replaceable insert nozzles direct the stream of liquid components into the chamber at a desired angle away from the outlet. A piston purges the mixing chamber of mixed fluids. A reciprocating sleeve coaxial with the shaft of the purge piston includes axial slots disposed to direct the flow of unmixed components from each inlet to its associated recycle port during purging of the mixing chamber.

Abstract: Malfunctions of plunger (15) in the mixhead (10) of a system for mixing a plurality of fluids such as polyol and isocyanate for the manufacture of polyurethane foam, which plunger induces variations in fluid pressures as the mixhead operates, are monitored by a method that includes the steps of measuring the upstream pressure of at least one fluid and generating a signal responsive thereto, and comparing the pressure responsive signal to a preselected pressure responsive signal and generating an alarm if the pressure responsive signal comparison falls outside preselected limits.

Abstract: A mixing head has a holding body, in which there is tightly supported a rotary body having inlet ducts for the materials to be mixed, leading to a mixing chamber. A delivery duct extends from the mixing chamber for delivering the mixed materials and the inlet ducts are selectively coupled to both plastic material inlet openings and to a washing fluid inlet chamber.

Abstract: An improved chemical injection assembly is disclosed of the type in which a hollow cylindrical housing with an outer surface defines an outer diameter and an inner surface defines an inner diameter. The hollow portion or bore defined by the inner surface in turn defines a cylindrical mixing chamber along the axis of the housing. At least one entry port assembly is positioned within the cylindrical housing prependicularly to the housing's axis. The port assembly comprises an entry opening that extends through the housing to form a path of fluid communication through the housing to the mixing chamber, and an entry fitting positioned in the entry opening. The fitting has front and rear coaxial portions with a common axial opening therethrough. The rear portion is adjacent to the housing and the front portion is adjacent to the cylindrical mixing chamber.

Abstract: An L-shaped mixing head for reaction injection molding apparatus comprises a first chamber wherein a plurality of reactive molding components are impingement mixed under high pressure. A second chamber intersecting with the first chamber quiets the resulting stream of mix product prior to its exiting the mixing head. The outlet end of the second chamber is defined by the inner surface of a sleeve, the material of which has a yield strength less than that of the materials of the mixing head body and the second plunger. Most preferably, the sleeve material is also chemically nonreactive with and nonadherent to the reactive molding components to be used therewith, both individually and as mixed.

Abstract: The present invention is directed to a process and apparatus for production liquid reaction mixtures. The invention includes a mix head with a mixing chamber which receives reactants through nozzle openings. The key feature resides in placing an impingement surface between at least one of the nozzle openings of the mix head and the mixing chamber itself.

Abstract: A mixing head for high pressure mixing of reactive chemicals defines a mixing chamber for receiving and mixing oppositely directed impinging chemicals and having an outlet through which the chemicals are discharged after mixing. A separate tubular nozzle assembly for each chemical is replaceably mounted in the body of the mix head and has an inlet for receiving one of the chemicals and an orifice communicating with the mixing chamber. Each nozzle assembly includes a nozzle body and an annular sleeve or ring shaped orifice member of abrasion resistant material defining the orifice and a tubular support fabricated from a non-metallic material, e.g., an internally lubricated super polyamide, snugly spacing the annular orifice member from portions of the nozzle body defining the associated passage and also interfitting with the annular orifice member in supporting relation.

Abstract: A two-component thermosetting polymer system is formed and dispensed by adding a foaming agent to one of two components of the polymer system. A solution of the foaming agent in the first component is formed in a supply tank. The foaming agent and first component solution is then mixed with a second component at a dispensing head or nozzle. By adding the foaming agent to only one of the two components and, in particular, by forming a solution of the foaming agent in the first component one is able to very carefully control the foam density of the cured end product.

Abstract: A cylindrical mixing chamber opens into a subsequent cylindrical quieting chamber at an acute angle alpha against its direction of outflow to avoid spattering during the output of a plastic mixture formed of a reactive plastic components from a mixing apparatus.

Abstract: An apparatus for continuously charging a liquid reactant with a gas is provided. The gas is dispersed in the reactant through a hollow stirrer in a gassing tank. The quantity of gas introduced per unit time is kept constant.

Abstract: A method of producing a polyurethane foam comprising the steps of dissolving rapidly and substantially completely a non-condensible non-reactive gas in a liquid isocyanate component or a liquid polyol component or both while the isocyanate and polyol components are maintained separate from one another, while controlling the flow of the non-reactive gas to maintain a predetermined dissolved gas to liquid ratio, and while maintaining the component in which the nucleating agent is being dissolved under pressure sufficient to maintain the gas in solution and to hold substantially constant the dissolved gas to liquid ratio and mixing the previously separated isocyanate and polyol components together while reducing the pressure to nucleate the dissolved gas in the isocyanate and polyol components and while impinging liquid streams of the composition together thereby enhancing mixing and permitting the mixture to foam so as to form a fine celled polyurethane foam.

Abstract: An improved static mixer for use in a plural component dispensing apparatus is disclosed having a spacer intermediate a plurality of mixing elements to enhance the mixing and blending of the plural components. The static mixer may employ an air assist to increase the mixing energy within static mixer.

Abstract: The present invention relates to an improved apparatus for the production of a flowable mixture which reacts to form foam from flowable components stored in storage containers, wherein prior to metered introduction into a mixing zone, at least one of the components is charged with a defined quantity of gas, by (i) introducing said one component and gas separately into a gasification chamber equipped with a hollow stirrer, (ii) sucking gas into said component through the hollow shaft of the hollow stirrer, and (iii) stirring the gas into the component, until the desired value is attained, the improvement wherein (a) the component is circulated from the storage container through the gasification chamber and back into the storage container, (b) the gas sucked through the hollow shaft of the hollow stirrer being maintained at pressure at least equal to the pressure prevailing in the storage container, and (c) the component fraction remaining in the storage container is homogenized during those periods in which ga

Abstract: The present invention is directed to an apparatus for introducing gas into one of at least two free-flowing components which are subsequently mixed to provide a foam-forming free-flowing mixture by transferring the component to have gas dispersed therein from a supply container to a gas loading area, loading the component with gas and returning the component to the supply area, wherein the gas used in the gas loading area is obtained from a gas cushion maintained in the supply container and wherein the gas is compressed to a pressure higher than the pressure in the gas loading area before it is dispersed into the free-flowing component.

Abstract: The present invention is directed to a novel process and apparatus for charging a liquid reactant with a gas. In the process, the liquid reactant which is as yet uncharged with gas is introduced into the gassing tank at a point just below the substantially constant liquid level of the reactant. When the reactant has been charged with gas, it is removed at a point below the region where gassing takes place. A three-layered arrangement is thereby established and maintained in the gassing tank so that the layer of gas is separated from the layer of gas charged component by the layer of uncharged component. The gas charged component is thus maintained at a density corresponding to the desired gas content, taking into account any significant starting conditions, such as the original density, the temperature and the pressure. If necessary, this density is maintained by suitably varying the stirrer speed.

Abstract: A closed loop feedback control for a high pressure impingement mixing system. The high pressure impingement mixing device is equipped with a circulation loop containing both a pressure sensor and a flow volume meter. Constant pressure and flow volume is achieved by continuous closed feedback loop monitoring of the pressure and flow volume to effect a change in an adjustable pump setting and servo displaceable nozzle needle. The nozzle needle adjustment allows maintaining the appropriate pressure and volume on a continuous spaces. It also allows altering component ratios and/or flow volumes during a shot in order to affect a change in material or flow characteristics of a produced part.

Abstract: The present invention relates to an improved process for the production of a flowable mixture which reacts to form foam from flowable components stored in storage containers, wherein prior to metered introduction into a mixing zone, at least one of the components is charged with a defined quantity of gas, by (i) introducing said one component and gas separately into a gasification chamber equipped with a hollow stirrer, (ii) sucking gas into said component through the hollow shaft of the hollow stirrer, and (iii) stirring the gas into the component, until the desired value is attained, the improvement wherein (a) the component is circulated from the storage container through the gasification chamber and back into the storage container, (b) the gas sucked through the hollow shaft of the hollow stirrer being maintained at a pressure at least equal to the pressure prevailing in the storage container, and (c) the component fraction remaining in the storage container is homogenized during those periods in which ga

Abstract: In order to keep the reversing times from circulation of the reaction components to mixing and vice versa as short as possible for the purpose of good mixing in the initial and end phases in the preparation of flowable reaction mixtures by high-pressure mixing, the holding pressure applied to the flow reversing element is maintained by a releasable non-return valve until the full hydraulic reversing pressure has built up on the opposite side, and only then is the non-return valve released.

Abstract: An impingement mixing device is provided comprising a mixing chamber housing, a control piston axially displaceable with said mixing chamber housing between an extended position and a retracted position, a mixing chamber within the housing defined by an end face of the control piston when in the retracted position and a mixing chamber discharge outlet coextensive with an end face of said control piston when in the extended position, means to feed first and second components to the mixing chamber in opposing relationship, a discharge tube housing defining a quieting chamber having an opening at a discharge end and in fluid communication with the mixing chamber, with said discharge tube housing including a sealing means adapted to at least partially close the opening of the quieting chamber at the discharge end.

Abstract: An apparatus for proportioning reaction mixtures, particularly for the manufacture of hard polyurethane foam. The apparatus includes two proportioning cylinders each for proportioning one of the components to a mixing head. The pistons of the two proportioning cylinders can be operated alternatingly for filling the cylinders with the compound and subsequently ejecting the component from the cylinders. Double-acting hydraulic cylinders driven by a common hydraulic pump operate independently from each other the proportioning pistons of the two proportioning cylinders. A servo-controlled proportional valve is provided in each of the connecting lines between the hydraulic cylinders and the hydraulic pump. The control cycles of the proportional valves determining the ejection of the two cooperating proportioning cylinders are adjusted relative to each other so as to temporarily overlap.

Abstract: A device for preparing a chemically reacting mixture and for ejecting the mixture into a mold, the mixture comprising at least two components, in particular a mixture of isocyanate and a polyol that reacts completely to form polyurethane, the device having a mixing head with an outwardly opening bore, and a reciprocable ram coupled to the head. The ram has an ejector rod axially movable in the bore for therewith defining a mixing chamber and for ejecting the mixture from the chamber. The head has inlet passages for inletting the components into the chamber for preparing the mixture. The ram is coupled to a rotational drive for rotating the rod about its longitudinal axis continuously during the preparation of the mixture to avoid any adherence of the mixture to the rod and/or to the wall of the bore. Alternatively, the rod may be oscillated about its longitudinal axis, or along its longitudinal axis.

Abstract: A mixing apparatus having a mixing chamber which has inlet ports of resin components to be mixed and an outlet port of a mixture thus obtained, comprising a flow varying member which moves across the mixing chamber to selectively occupy a retracted position in which it is retracted from the mixing chamber and a forward position in which the flow varying member interrupts the flow of the resin components to change the directions thereof, an immovable key member which defines a restriction passage together with the flow varying member which occupies the forward position, and a chamber block which is opposed to the flow varying member to laterally move in order to selectively occupy a forward position in which it defines a part of the mixing chamber and a retracted position in which the chamber block defines a flow varying chamber together with the key member and the flow varying member which occupies the forward position.

Abstract: An improved mixing device for mixing at least two of a plurality of pressurized liquids, the device consisting of hollow tubular member defined as having a longitudinal axis, one or two open ends and an interior wall member, one of the open ends having at least two cut-out portions generally symmetrically disposed about the axis, a segmental slot member generally radially disposed in the hollow tubular member between each of the cut-out portions for receiving a supporting projection in locking engagement therewith, and an envelope mounted on and extending about each of the cut-out portions for receiving and encompassing a conduit member terminating at and within each of the cut-out portions, each envelope being disposed, constructed and arranged for directing one of the plurality of pressurized liquids onto a proximate area of the interior wall means thereof.

Abstract: A mixing head of an injection molding machine has an injection plunger for opening and closing a plurality of orifices and a spool plunger for opening and closing a plurality of circular passageways. The plunger and the spool are disposed parallel to each other.

Abstract: A closed loop feedback control for a high pressure impingement mixing system. The high pressure impingement mixing device is equipped with a circulation loop containing both a pressure sensor and a flow volume meter. Constant pressure and flow volume is achieved by continuous closed feedback loop monitoring of the pressure and flow volume to effect a change in an adjustable pump setting and servo displaceable nozzle needle. The nozzle needle adjustment allows maintaining the appropriate pressure and volume on a continuous spaces. It also allows altering component ratios and/or flow volumes during a shot in order to affect a change in material or flow characteristics of a produced part.

Abstract: Viscous liquids containing polymeric materials which will interact with one another upon contact and generate gas for foam expansion are intimately and homogeneously mixed in a very short period of time by passing them successively and continuously through first and second rotary dynamic shearing mixers, the first mixer being considerably smaller than the second mixer, and the mixture experiencing a brief period of respite from shearing between the two mixers. The mixture experiences a much higher degree of shear in the first mixer, where the heat necessary for promoting the reaction is provided through the shearing action but without creating localized hot-spots. The process is particularly well suited for the preparation of foamed polydiorganosiloxanes, on a continuous, commercial scale.

Abstract: The apparatus for mixing multicomponent plastics, in particular polyurethane, has a steadying attachment 1 which is arranged at the outlet orifice 12 of a mixing head 10. The steadying attachment is equipped with a plurality of lamellae 3 which are movable in the region of the emerging mixture of components and run in the direction of flow of the said mixture. Advantageously, the lamellae can be moved forward and back in a guide housing which has webs 2 which occupy the space between the lamellae and thus ensure cleaning. Steadying is achieved by greater friction with the wall and an increase in the outflow cross-section.

Abstract: The invention refers to a high-pressure mixing device, for at least two chemical components to be mixed, in particular of the type having a movable mixing chamber, in which the mixing chamber communicates with an outlet duct for discharging the mixture therefrom through a lateral passage and in which the component inlet apertures open directly into the mixing chamber but are oriented so as to face away from the lateral passage in a direction which is opposite to the flow of the mixture in the outlet duct.

Abstract: A RIM apparatus has a separate hydraulically actuated monomer dispensing system associated with one of at least two different fluid chemical monomers to be mixed and molded. Each system is connected with a separate hydraulic fluid delivery cylinder (one for each monomer) for receiving hydraulic fluid therefrom and is operable for dispensing the associated monomer to a RIM mixing head and mold at a rate proportional to the rate that said hydraulic fluid is delivered thereto from the connected delivery cylinder. Each delivery cylinder is supported at a preselected position with its axis spaced radially from a reference axis and at least one thereof is bodily adjustable radially with respect to said reference axis and to the axis of another delivery cylinder. Each delivery cylinder discharges hydraulic fluid at a rate proportional to the rate of movement of an associated piston therein.

Abstract: An improved process for producing a molded microcellular elastomer with a reduced number of voids from at least two liquid reactants and a gas, which process comprises introducing into at least one reactant a gas to form an admixture; passing the admixture through a static mixer at superatmospheric pressure; then immediately mixing the admixture with the other reactant at superatmospheric pressure to form a reaction mixture; introducing the reaction mixture into a mold in which the pressure is substantially below the superatmospheric pressures used above; and curing the reaction mixture in the mold to produce a molded microcellular elastomer with a reduced number of large voids.

Abstract: The device of the present invention is used for the production of a reaction mixture. The device has a housing with a guide bore provided therein for an injection piston. Feed lines with entry openings and recirculation lines are provided. The device is also provided with a rotary slide valve which contains a mixing chamber through which the ejection piston can pass. The slide valve is movable to a position that frees the entry openings to the mixture chamber and to a position that connects the entry openings (through flow channels provided in the rotary slide valve) with the recirculation lines.

Abstract: A mixing head is created for mixing two plastic-forming components, having a mixing chamber and an ejection piston guided in a passage of the same cross section, in which, while retaining the mechanical self-clearing of the exit passage and mixing chamber by the eject piston and an intensive mixing of the reaction components, a quieting of the liquid component mixture after leaving the mixing chamber is achieved by providing a transversely movable choke member at the downstream end of the mixing chamber. When the choke member is in the choke position, one side of it situated in the exit passage forms a choke gap expanding diffuser-like toward the exit opening of the exit passage, and in a cleaning position, a cavity which it contains is brought into alignment with the exit passage, so that the eject piston can perform its passage clearing stroke.

Abstract: The invention relates to a nozzle for mixing at least two flowable (and in particular foam-forming) reaction components comprising a housing; component supply pipes leading into the housing; a housing bore arranged in the housing having a coaxial outlet channel in its end face; at least one needle casing arranged coaxially in the housing bore; an injection needle guided coaxially in the needle casing; a first chamber arranged between the wall of the housing bore and the needle casing with one of the component supply pipes opening into said first chamber; a second chamber arranged between the needle casing and the injection needle, with another component supply pipe opening into said second chamber; wherein in the closed state, said injection needle forms a tight fit with the internal end face of the needle casing, and the external end face of said needle casing forms a tight fit with the internal end face of the housing bore; and wherein in the open state, said injection needle frees a coaxial nozzle opening

Abstract: A portable foam generator is provided for admixing air under pressure with a foamable liquid under pressure in order to foam the liquid and the foamed liquid is supplied to a spray nozzle for spray applying the foamed liquid to differently oriented surfaces which are to be cleaned and/or disinfected. The foam generator incorporates a feature which enables the "wetness" of the foam discharged from the nozzle to be varied and to thereby enable the foamed liquid applied to downwardly facing surfaces, inclined surfaces and vertical surfaces to experience extended liquid to surface to contact time.

Abstract: A high-pressure mixing head for at least two fluid components to be mixed together.The mixing head comprises a movable mixing chamber, defined by a cylindrical hole whose longitudinal axis is parallel to the axis of an outlet duct; the mixing chamber is provided in a slider movable in a guide channel at right angles to and crossing the outlet duct for the mixture. The slider is movable from a first operative position in which the chamber is disposed on one side of the outlet duct, in correspondence with the nozzles for injecting the components to be mixed, and in which the outlet aperture of the mixing chamber communicates with the outlet duct, to a second position in which the injectors communicate with component recycling ducts, and in which the mixing chamber is axially aligned with the outlet duct and with a sliding cleaning member.

Abstract: A high pressure mixing head for mixing reactive components in reaction injection molding includes a mixing chamber discharging into a quieting chamber and an injection valve for injecting reactive component into the mixing chamber. Recirculation passages for the reactive component are provided in the mixing chamber and internally of the injection valve. The recirculation passage internally of the injection valve is selectably opened and closed as is the outlet from the injection valve into the mixing chamber. Both the injection valve outlet and the recirculation passage internally of the injection valve are selectably throttleable.

Abstract: An impingement mixing device for preparation of plastic parts or objects including cellular foam from at least two reactive synthetic components and an auxiliary component such as liquid foaming agent and including at least two injection ports and a third port for input of the auxiliary component. Inert gas optionally and a foaming agent and further additives are mixed at a point in the cylindrical wall of the component mixing chamber located in or near the vicinity of the radial plane passing through the component openings. The introduction of the inert gas, foaming agent, coloring agent, or further additives is controlled by a cleaning piston which also simultaneously cleans the mixed plastic material penetrated therein from the opening area of the inert gas feeder line. The cleaning piston is part of a control piston, which with its rear segment is located in a metering chamber for the inert gas and optionally also for the foaming agent and the additives.

Abstract: The invention relates to a mixing head for the mixing of at least two components forming a synthetic material, the mixing head comprising a mixing chamber and a discharging channel which is guided in a guide channel having a symmetrical cross-section. The mixing head is operable to provide mechanical self-cleaning of the discharging channel and mixing chamber by a discharging piston. An intensive mixing of the reaction components is achieved along with stabilization of the liquid mixture of the components after the mixture has left the mixing chamber in that a throttle member provided at the downstream end of the mixing chamber, is movable in and out of the cross-section of the channel and forms in its throttling position, a throttle slit which is flared towards the outlet opening of the discharging channel like a diffusor.

Abstract: Disclosed is a high-pressure mixing head for the mixing of at least two reactive plastics material components and the foaming of these components, the mixing head comprises a mixing chamber (18) which has opening thereinto nozzle orifices (22; 24; 41) for the plastics material components and a blowing agent, and in which a metering plunger (20) is mounted for reciprocating movement. The mixing chamber (18) opens into a discharge section (16) of greater dimensions which, thus, acts as a stabilizing zone. On the mixing chamber outlet (26), a variable damper element (purging plunger 12; damping plunger 40) is provided which provides for variable restriction of the mixing chamber outlet (26). The damper element greatly reduces the mixing turbulence within the mixing chamber, such that, in combination with the discharge section of greater dimensions, the plastic foam mixture flows out from the mixing head so smoothly that spatter-free foaming even in open molds becomes possible.

Abstract: The mixing head is provided with a flow restrictor 5 which can be driven into the mixing chamber 2 downstream of the inlet orifices 3, and whose front face (for 6) is matched to the contour of the mixing chamber to avoid leaving any space here which cannot be purged by the purging plunger. When the flow restrictor is pushed forward into its working or restricting position, it is simultaneously rotated, the extent of rotation being no more than 90.degree. by the time the restricting position has been reached. This makes it possible to drive the flow restrictor much further into the mixing chamber than when no rotation is effected. The tongues or projections 6 produced as a result of matching the front face to the contour of the mixing chamber only come into contact with the sections of the mixing chamber wall which are opposite the flow restrictor.

Abstract: A piston metering device for the production of a plastic material from at least two flowable reaction components. This device is basically composed of (a) a hydraulic driving mechanism, (b) two piston cylinder units, (c) a mixer head and, optionally, (d) a control device common to at least one of the piston cylinder units. This device permits rapid and simple adjustment of the metering ratio of reaction components by adjustment of throughput. Such adjustment is accomplished by means of regulating elements made of hydraulic motors rigidly coupled to one another.

Abstract: A high pressure mix-head for use in reaction injection molding systems includes a full cross section plunger and a piston valve assembly selectively positioned in response to recirculation and pour cycles to control flow through recirculation passages formed on the O.D. surface of a mix-head sleeve.

Abstract: A process and apparatus for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and simultaneously recovering the foaming agent volatilized from the thermoplastic resin particles by discharging the foaming agent out of the space in the low-pressure vessel with controlling the pressure in the low-pressure vessel to substantially a given pressure. According to the process, the release of the volatile foaming agent into the air is prevented.

Abstract: A process and apparatus for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel and the space is sealed with an aqueous medium which exists in the lower portion of the vessel and communicates with the outside of the vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and sinking the resulting pre-expanded particles under the aqueous medium by means of a rotary impeller provided in the pressure vessel so that the pre-expanded particles are taken out of the low-pressure vessel through the aqueous medium towards the outside of the vessel, while recovering the foaming agent volatilized from the thermoplastic resin par

Abstract: The mixing pistol for reactive multiple component materials includes a self rotating mixing rotor in a mixing chamber, and several valves controling the injection of a component into the mixing chamber. Additionally there are valves for the injection of cleansing solution and compressed air. While cleansing the mixing chamber, in order not to have to remove the used cleansing solution by way of the outlet of the mixing pistol, which would be connected with the removal of dangerous and harmful fumes and gases, there is an additional outlet valve arranged at the mixing chamber by means of which the removal of the used cleansing solution is accomplished. The cleansing solution is driven in the mixing chamber in a closed circulation and never comes into contact with the outer region of the mixing pistol.

Abstract: A mixing and dispensing gun comprising a body having spaced inlets for receiving two components of an adhesive or reactive fluid, a dispensing valve in the gun, an outlet nozzle and a motionless mixer interposed between the dispensing valve and the outlet nozzle for directing the fluids in a sinuous path and mixing the fluids.

Abstract: An insulating foam and a process for producing insulating foam, wherein a foamable first component may be made of alkyl sulfate, half ester of maleic anhydride and acrylic resin in an aqueous solution is mechanically foamed with air, and to that foam is added an aqueous solution of magnesium oxide, dispersant, acrylic resin, perlite and/or precipitated calcium carbonate. To those components is added an aqueous solution of at least one of aluminum chloride, magnesium sulfate, magnesium chloride, zinc chloride, sulfamic acid, sodium silicate, zinc oxide, barium metaborate, vinyl alcohol, magnesium carbonate, calcium chloride and vinyl acetate. In another embodiment a polyvinyl alcohol and dispersant first portion is foamed with air and mixed with a second cementitious portion comprising magnesium oxide and barium metaborate.

Abstract: The foam is produced by mixing an isocyanate with a polyalcohol from a tight storage tank with two compartments, each of which contains one of the aforementioned products, the upper part of the tank being provided with a solid propellant trip or starter, which generates a pressurization gas form the tank. In the lower part of the storage tank, there is a pressure threshold mixer, whose operation is automatically controlled by the pressure prevailing in the tank and which has a mixing chamber entered (under the effect of the same pressure) by the isocyanate and the polyol via lateral injection nozzles, which produce a rotation of the mixture, the polyols being previously emulsified by a neutral gas (such as air or nitrogen) from a pressurized storage container.

Abstract: A mixing method and apparatus for preparing multi-component plastic materials, especially polyurethanes, which are mixed before being fed into a mold. According to the invention, a first and at least a second main component are mixed by feeding them into a limited area of a mixing chamber through lateral inlet apertures symmetrically arranged with respect to a plane comprising the longitudinal axis of the chamber and in which a third or secondary component to be mixed is fed through a channel, opening in the chamber upstream of said inlet apertures and orientated so as to direct the flow of the third or secondary component towards said mixing area in the direction of flow of the mixture. A control member is moved toward an advanced position so that it closes the inlet apertures to interrupt feeding of the first and second main components and a coloring agent through respective inlet apertures after a mixing operation.

Abstract: A high pressure mix-head for use in reaction injection molding systems includes a full cross section control piston and body slots and primary pour orifices for establishing pressure balance during recirculation and pour cycles.