JPS6210162B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an apparatus for the continuous production of polyurethane foam. Apparatus for generating foams are well known and widely used, primarily for applying the foams to textile materials and the like. The foam composition is applied to a substrate, and when it contacts the substrate, the foam ruptures and the composition is absorbed into the substrate. Foaming generally consists of a mechanical stirrer capable of mixing metered amounts of a gas such as air and a liquid chemical composition containing the chemicals to be applied to the substrate and forming the mixture into a foam. It is generated in a device that converts it into However, structurally stable polyurethane foams cannot be produced using prior art foam generators. U.S. Pat. No. 3,821,130 describes a polyether polyol end-capped with at least 2 moles of ethylene oxide per active hydrogen atom, a polyisocyanate-containing material, and a urethane-forming catalyst, foamed with an inert gas. Flexible polyurethane foams made from mixtures are described. The polyether polyol and polyisocyanate are used in amounts such that the NCO:OH ratio is about 0.85:1 to 2.0:1. The patent states that the foam does not require the use of volatile blowing agents or silicone oil foam control agents. The foam of this patent specifies that an inert gas is mechanically introduced into the urethane-forming composition to create a foam, and the foam is applied to a suitable mold or onto a suitable substrate where it is foamed. It is produced by coagulating the mixture into a foamed polyurethane product. This patent teaches that conventional foams obtained by mechanically introducing inert gases into urethane-forming compositions are produced in very small amounts;
That is, it is stated that there is no subsequent significant expansion other than thermal expansion of the inert gas used, which is less than about 1% by volume. Column 3 of this patent specification describes various foam production methods. These methods include mechanically agitating or mixing air or an inert gas into the mixture of urethane-forming components using a mixer with blades designed to mechanically agitate the air into the mixture. That is included. Another method is to feed a stream consisting of a mixture of urethane-forming components, or a separate stream of each urethane-forming component, and a stream of air to a foam-generating mixer, and the foamed composition exiting the mixer into a mold. , or onto a substrate where the foamed composition is thermally cured into a flexible polyurethane.
Yet another method described in this patent includes feeding an inert gas and all urethane forming components other than the catalyst to a foam generating mixer, then adding the catalyst to the foam generating mixer.
The resulting foam is mixed in a mixer, for example a static mixer, and then the foam is introduced into a mold or onto a substrate. Examples 1-13 of this patent specification disclose the use of impellers to foam polyether polyols and isocyanate-containing materials at high speed for a period of time sufficient to agitate air within the mixture, typically 2 minutes. Place in the prepared Hobart mixer. After the foaming is completed, add the catalyst and
The resulting foam is mixed for an additional 45 seconds, then poured into an open container and allowed to harden. However, this patent specification does not describe an apparatus for continuous production of foam. The present invention relates to an apparatus for the continuous production of curable polyurethane foam. The apparatus comprises separate sources for a polyol, an isocyanate, a catalyst and an inert gas; and a supply of the polyol, isocyanate and inert gas separately and under pressure from the sources at controlled flow rates. means including separate conduits for feeding a mixing device having inlet openings for receiving polyol isocyanate and inert gas; means for mixing said polyol, isocyanate and inert gas to produce a foam; , and an outlet opening for the resulting foam; means for conveying the foam from said mixing device to a second mixing device; and a second mixing of the catalyst at a controlled flow rate under pressure. a conduit for feeding a device; means for mixing the foam and catalyst, the mixing device having an inlet opening for receiving the foam and catalyst and receiving the resulting catalytic action; and means for delivering the catalyzed foam from the mixing device onto the substrate. We have found that the apparatus of the present invention produces polyurethane foams that are structurally stable and easily processable at ambient temperatures. The foam has a density of about 18 to about 45 pounds per cubic foot, preferably about 20 to about 35 pounds per cubic foot. The resulting foam form can be used, for example, in adhesives for gluing panels together into frames, in particular for gluing dry wall panels into wooden frames; flame retardant insulation materials; insulating materials; wood repairs; concrete repairs; cinderblock repairs; can be formed into temporary sidewalks or walkways on soft ground; highway medians; filling materials for holes in columns to eliminate contact between the column and the ground; covering, protective and insulating jackets for buried piping; filling materials; repairing holes, dents in vehicles; joints in dry walls; It has uses such as a sealer. The cured polyurethane foam has a substantially closed cell structure. The bubbles are substantially spherical and have a diameter of about 300 microns or less. The bubble diameter ranges from about 5 microns to about 300 microns. The size of the cells forming the skin of the polyurethane foam is substantially equal to the size of the cells in the interior center of the foam. Thus, from surface to surface, the cell size of the polyurethane foam is substantially uniform except for the cells that adhere to and are adjacent to the substrate. Such uniformity reflects the average uniformity found in the center of the polyurethane foam as described above. The density of the cured foam is approximately equal to the density of the foam before curing. Cured polyurethane is resilient, sandable, and easily painted. To more clearly describe the multiple embodiments of the invention, reference is made to FIG. 1, which shows a schematic flow diagram of a preferred embodiment of the invention, and to FIG. 2, which shows a side view of containers 29 and 30 of FIG. In discussing FIGS. 1 and 2, the description herein is purely illustrative and not limiting in any way. Numerous structural modifications and various embodiments will suggest themselves to those skilled in the art to which this invention pertains without departing from its spirit and scope. polyol packages contained in containers 29 and 30 (which polyol packages will hereinafter be referred to as "polyols" for purposes of this discussion), container 2;
The isocyanate contained in 8 and the catalyst contained in vessel 27 are pumped to the mixer by pumps 34, 33 and 32, respectively. These pumps are driven by a motor 35. Since all pumps are positive displacement pumps, the use of one motor to drive each pump ensures a fixed, constant ratio of material from containers 27, 28, 29 and 30. Ru. The polyol is removed from containers 29 and 30 and pumped at a constant rate by pump 34. The output of the pump 34 is fixed to the speed of the drive motor.
The pump is a Moyno unit (Robbins and Meyers).
Corporation). The output can be varied from about 100 to about 200 grams per minute by varying the drive speed and adjusting the component dimensions. Isocyanate is removed from tank 28 through conduit 55 and optionally through filter 57.
Filter 57 removes all impurities and previously reacted materials. Pump 33 may be a gear type unit manufactured by Zenith Corporation;
This output, as measured by the speed of the drive motor 35, is between 30 and 60 g/min or more. This discharge is distributed through conduits 59, 61 and 64 and valve 62.
carried through. At various times during the foam generation process, it may be desirable to interrupt the isocyanate flow without interfering with the flow of other systems. This capability is realized by valves 62 and 66 and conduits 67 and 65. By blocking flow through valve 62, the output of pump 33 reaches a pressure of approximately 100 psi, which opens check valve 66 and allows fluid to flow into conduit 65. This fluid is then passed through the drive motor 3
Recirculate through filter 57 and pump 33 until 5 stops or valve 62 reopens. Similarly, catalyst is removed from tank 27 through conduit 77, pumped by single piston pump 32, and metered. By closing valve 81, a flow of about 0.5 to about 5 g/min of effluent can be recirculated. This allows conduit 8
4 and 83, at which time the pressure of the discharge automatically opens check valve 85. Chemical supply tanks 27, 28, 29 and 30
is pressurized to minimize the possibility of contamination and to reduce the power output required by motor 35. This connects gas from tank 1 to a set of pressure reducing valves 5 and 9 and control valve 1.
1 and into the top of each tank through conduit 20. In this way, the chemical fluid reaches the same pressure as conduit 20, approximately 60 psi, facilitating fluid flow to each pump through the inlet conduit, thus minimizing cavitation and unreliable metering. Foam generation is accomplished mechanically by a mixer 47 driven by a motor 48. Air is removed from tank 1 through valves 5, 18, 70 and 73 and conduits 17, 68, 69, 72 and 74 such that a constant flow rate is maintained. The air and polyol are introduced into the mixer through conduit 46. The isocyanate is added via conduit 64, mixing the polyol with air and then stirring to form a foam. Conduit 64 has a small diameter to maintain high fluid velocities and minimize any backflow of reactants that could cause blockages. The urethane foam is sent via conduit 75 to catalyst injector 76 . Catalyst flows to the catalyst injector via conduit 82. Conduit 82 has a small diameter to facilitate consistent system operation.
operation) to minimize conduit and fluid elastic effects. The foam and catalyst pass to a static mixer 86;
The mixer mixes the ingredients to a uniform homogeneity. The curable foam can be applied directly to the substrate or can be applied by an applicator 87. The purpose of application with this applicator is to distribute the foam in the desired form. In particular, in FIG. 1, container 1 is a source of dry gaseous material, preferably dry nitrogen or dry air.
Gas from vessel 1 passes through conduits 2 and 4 under a pressure of about 2700 psig and then passes through pressure reducing valve 5 where it is reduced to about 200 psig. A portion of the gas passes through conduits 6 and 7 to pressure reducing valve 9, which reduces the pressure to approximately 60 to 70 psig. The other part of the gas passes through conduits 6 and 17 to pressure reducing valve 18;
The pressure reduction valve reduces the pressure to about 100 to 150 psig. A pressure switch 8 monitors the gas supply level. Gauge 3 displays gas pressure. Gas from pressure reducing valve 9 passes through conduit 10 to control valve 11 and then via conduits 12 and 20, partly through conduit 26 to create pressure on the contents of container 27 and partly through conduit 26. Container 2 via 25
Pressure is applied to the contents of conduits 21 and 2.
applying pressure to the contents of the container 29 via step 2;
A portion applies pressure to the contents of container 30 via conduits 21 and 24. In an optional embodiment, gas flows from valve 11 via conduits 12 and 14 through pressure reducing valve 15 where it is reduced in pressure to 5 psi and then through conduit 16 where it pressurizes the contents of vessel 93. .
The contents of container 93 consist of a cleaning or cleaning solvent. When the operation is started, the containers 29 and/or 3
The polyol in vessel 28, the isocyanate in vessel 28 and the catalyst in vessel 27 are pumped to the mixer by pumps 34, 33 and 32, respectively. The pumps are driven by a motor 35. In particular, the polyol contained in containers 29 and 30 are contained in conduits 36 and 31, respectively.
, then through conduits 37 , 38 and 41 , through pump 34 and conduits 42 and 46 to mixer 47 . The mixer is driven by a motor 48. The polyols in containers 29 and 30 can be used simultaneously or sequentially. In a preferred embodiment, the container 29
and 30 are floating pistons 52 and 53
has. These pistons assist in completely emptying the container (especially when using viscous polyols). Additionally, the piston cuts off the polyol supply when the container is empty, allowing flow to begin from the second container. Pressure switch 54 detects the pressure difference and indicates that both tanks are empty. Container 40 is a receptacle for the polyol. It is a 1 quart bladder accumulator. When pumping is initiated, polyol from either vessel flows into the accumulator 40 and fills it. When both containers 29 and 30 are empty of polyol, pressure switch 54 is actuated and the polyol from container 40 flows under reduced pressure into pump 34 and mixer 47 as previously described, resulting in continuous work interruptions. Prevent cavitation during use. Isocyanate is transferred from container 28 to conduits 55 and 5.
6, optionally through filter 57, via conduit 58 and through pump 33 to conduits 59 and 6.
1, valve 62 and then pumped via conduits 63 and 64 to mixer 47. Sometimes it is preferable to interrupt the flow of isocyanate without stopping the flow of other components. In this optional scheme, flow is interrupted by closing valve 62, thereby allowing the output of pump 33 to reach a pressure of approximately 100 psi, which opens valve 66, passing the isocyanate into conduit 65. . The isocyanate is then passed through the filter 57 and the pump 33, the motor 35 is stopped, and the
Alternatively, recirculate until valve 62 reopens. Air is supplied to mixer 47 to produce foam. Air flows from tank 1 to conduits 2 and 4, valve 5, conduits 6 and 17, pressure regulator 18, conduits 68 and 69, directional control valve 70, conduit 72, flow rate regulating valve 7
3, through conduit 74, where the air
3 with the polyol from conduit 42;
Both substances then pass through conduit 46 to mixer 47
leading to. At the same time, isocyanate flows into mixer 47 as described above. The generated foam is transferred from the mixer 47 to the conduit 75.
It is sent to the catalyst injector 76 via. The catalyst is passed from vessel 27 through conduits 77 and 78, through pump 32, through conduits 79 and 80 to valve 8.
1 and then via conduit 82 to catalyst injector 76. In an optional embodiment, valve 8
1 is closed, which causes valve 85 and conduits 83 and 78 to open automatically when the pressure causes valve 85 to open automatically.
Recirculation can be achieved by creating a flow through. A preferred catalytic injector is B. ``Apparatus for Mixing Chemical Components'' filed by B.Pinkston on January 8, 1980 and assigned to the same assignee as the present invention.
No. 115,623 entitled ``Component.'' The apparatus described in said Patent Application Serial No. 115623 is an apparatus for producing a mixture of chemical compositions, the apparatus comprising: (a) extending through a housing;
(b) one or more inlet means for supplying a species component into the tube so that said component flows from the inlet means to an outlet means at the other end of the tube; an inlet means for supplying at least one component that is either reactive with component (a) or catalyzes the reaction of two or more components of (a); (c) means for distributing the component from the annular groove to a plurality of grooves in the conical member; In one embodiment, said channel comprises an elongated housing having said means for directing said component into the flow of component (a) within said tube. A static mixer 86 mixes the catalyst and the foam. The foam is then deposited onto the substrate by an applicator 87. Applicator 87 can arrange the foam into a desired shape. In an optional embodiment of the invention, a solvent may be used to perform the cleaning described below. Conduit 64 transporting material from the isocyanate container; Conduit 75 transporting foam from mixer 47; Catalyst injector 76; Mixer 86; and Applicator 87. Air is transferred from the control device 11 to the conduit 12 and the tee 1
9, through the conduit 14 and the control device 15, to the control device 1
5 reduces the pressure to approximately 5 psi as necessary, conduit 16
through the container 93 and the solvent therein is pressurized to create pressure on the contents of the container 93. Conduit 101 in preparation for use with a solvent cleaning method
directing air from the air into conduit 104 by valve 103;
Cavity 94 in cylinder 105 (cylinder 105 has a 2 inch hole) is filled and pressurized. This moves the piston rod assembly 95,
This increases the volume of cavity 96 within cylinder 108. (Cylinder 108 has a 4 inch bore.) As the volume increases, solvent is withdrawn through conduit 88, check valve 90 and conduit 107 to fill cavity 96. This system is easy to clean. If it is desired to clean the system,
Air from conduit 101 now enters conduit 102 and electrically drives valve 103 to another position so as to fill and pressurize cavity 97. The pressure used in cavity 97 then reduces the volume of cavity 96 and the solvent therein passes through conduit 109, check valve 110 and conduits 111 and 64 and enters mixer 47, washing the material therein. to clean downstream components present through the mixer and ultimately the applicator 87. Preferred solvents are halogenated hydrocarbons such as methylene chloride or ketones such as acetone or methyl ethyl ketone. The total end-to-end travel of piston rod assembly 95 is 3 inches. Figure 2 is used to hold the polyol package. Figure 2 is a side view of the containers shown as 29 and 30 in Figure 1; Tank cylinder 201 is 7
It is a gallon aluminum tube with a top 207
, to which a handle 208 is attached. The top can be removed and the polyol added. O-rings 205 provide a seal to prevent material from leaking between the top and sides of the cylinder. Air inlet 203 receives air under pressure and creates pressure on piston 206 to force it against the contents of the container;
The contents are forced through the suction tube 202 and into the system through the outlet 204. When the cylinder is emptied, piston 206 is in the piston A state, sealing the system by sealing suction tube 202. If the catalyst is injected into the foam and then mixed with the foam in a mixer, the curing time of the foam is greatly reduced. Using this foam catalytic technique, most of the curing takes about 90 seconds in bulk and about 30 to about 50 seconds in thin layers.
Can occur within minutes. Moreover, the addition of the catalyst, in addition to promoting curing, prevents gelation or the accumulation of highly viscous or gelled materials on the walls of the hose, thereby prolonging the operational life of the foam in the hose. maintain. The hose transports the foam from the mixer onto the substrate on which it is deposited. Additionally, the addition of catalyst minimizes secondary foaming after the foam has been applied to a substrate, such as a joint formed by two adjacent wall panels. When the isocyanate reacts with moisture to produce CO ₂ , secondary foaming occurs resulting in an uneven surface. As mentioned above, the addition of catalyst accelerates curing as the foam is applied through the hose to the substrate, thereby allowing secondary foaming when using sufficiently low hygroscopic polyol(s). is virtually eliminated. B. January 1980 by B. Barth et al.
“A Frothable Polyurethane Composite and Cellular Foam Produced Therefrom” filed on 28th April 2013 and assigned to the same applicant as the present invention.
Polyurethane Composition and Cellular Foam
Co-pending U.S. Patent Application Ser. The curable foam by mixing air or other gaseous substances with a polyol (including a thixotrope and one or more optional ingredients) and an isocyanate, as described in said patent application. is manufactured. Preferably, the catalyst is added to the foam made by mixing the gas, the polyol (including the thixotrope and one or more optional ingredients), and the isocyanate. Suitable gaseous substances for use in the present invention include any gaseous element that exists in a gaseous state at standard temperature and pressure, i.e. 25° C. and 1 atm;
Compounds or mixtures thereof, such as helium, nitrogen, oxygen, carbon dioxide and air, or mixtures thereof. provided that they do not react with or significantly dissolve in any of the urethane forming components. In particular, in preparing the curable foam, an isocyanate, a thixotrope-containing polyol, and one or more optional ingredients are used.
Weigh separately and proportioned into a mixer, preferably an SKG or Oaks continuous mixer. The gaseous substance under pressure is either a polyol or an isocyanate stream,
or both, or directly into the mixer containing the polyurethane-forming components. A dense foam is formed in the mixer at pressures above atmospheric and from about 40 to about 150 psig.
The foam is then fed from the mixer into a delivery tube. As the foam progresses toward the outlet of the delivery tube, the volume of the foam expands (i.e., its density decreases) as the entrained air bubbles expand as the pressure decreases.
do. Catalyst was injected into the foam at a point downstream of the delivery tube and dispersed by passing the foam/catalyst mixture through an in-line mixer. The catalyzed foam was then directed onto the substrate. The compositions suitable for use in the present invention and described in the aforementioned U.S. Patent Application Ser. The density of the cured foam is substantially the same as the density of the foam composition when cured with at least one side of the foam exposed to the atmosphere. The composition can be used to react with (a) a polyol, (b) a polyisocyanate, (c) a thixotropic agent, (d) an inert gas, and (e) a polyisocyanate, but only if the composition is cured. The foamed polyurethane contains an amount of water that is less than the amount that results in a foamed polyurethane having a density that is essentially different from that of the foamed composition. The composition comprises a catalyst and optionally a surfactant,
It may contain one or more of hygroscopic materials, fillers, flame retardants, dyes, pigments, or any other ingredients that do not introduce significant amounts of moisture into the composition. Compositions such as those described in said U.S. Patent Application Ser. It is preferable to use the catalyst package in the form of an isocyanate package containing a catalyst for catalyzing the urethane production reaction and a solvent for the catalyst. An inert gas is used to generate the foam. Suitable polyols or polyol mixtures useful in the present invention have the following characteristics: an average hydroxyl number as low as possible, not greater than about 300;
The viscosity at 25°C is about 5000 or less, preferably about
2000 centipoise or less; organolepticity equal to or greater than 2, preferably equal to or greater than 3; hygroscopicity (30 g sample placed in a 25/8 x 7/8 inch circular metal dish at relative humidity of 90 Weight increase (%) when left in a humidity control room at 26°C for 24 hours) is about 7 or less, preferably about 1 or less. Polyols contain active hydrogen-containing components, such as: hydroxyl-terminated polyhydrocarbons (U.S. Pat. No. 2,877,212); hydroxyl-terminated polyformals (U.S. Pat. No. 2,877,212);
2870097); fatty acid triglycerides (US Pat. Nos. 2833730 and 2878601); hydroxyl-terminated polyesters (US Pat. Nos. 2698838, 2921915, 2591884,
No. 2866762, No. 2850476, No. 2602783, No.
No. 2729618, No. 2779689, No. 2811493 and No.
2621166); hydroxymethyl-terminated perfluoromethylene (U.S. Pat. No. 2911390 and 2902473; British Patent No. 733624); polyalkylene arylene ether glycol (U.S. Pat. No. 2808391); Alkylene ether triol (U.S. Patent No. 2866774)
No. Specification). Particularly preferred polyhydroxyl-containing materials are polyether polyols obtained by chemical addition of alkylene oxides with water or polyhydric organic compounds, said alkylene oxides being, for example, ethylene oxide, propylene oxide and mixtures thereof, and said polyhydric organic compounds For example: ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol,
1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,2-hexylene glycol, 1,10-decanediol, 1,
2-cyclohexanediol, 2-butene-1,
4-diol, 3-cyclohexene-1,1-dimethanol, 4-methyl-3-cyclohexene
1,1-dimethanol, 3-methylene-1,5-
Pentanediol, diethylene glycol, (2
-hydroxyethoxy)-1-propanol, 4
-(2-hydroxyethoxy)-1-butanol, 5-(2-hydroxypropoxy)-1-pentanol, 1-[2-hydroxyethoxy]-
2-hexanol, 1-(2-hydroxypropoxy)-2-octanol, 3-allyloxy-
1,5-pentanediol, 2-allyloxymethyl-2-methyl-1,3-propanediol, 3
-(o-propenylphenoxy)-1,2-propanediol, 4,4'-isopropylidenebis(p-phenyleneoxy)diethanol, glycerol, 1,2,6-hexane-triol,
1,1,1-trimethylolethane, 1,1,1
-trimethylolpropane, 3-(2-hydroxypropoxy)-1,2-propanediol,
2,4-dimethyl-2-(2-hydroxyethoxy)-methylpentanediol-1,5;1,
1,1-tris[(2-hydroxyethoxy)methyl]-ethane, 1,1,1-tris[(2-hydroxyethoxy)methyl]ethane, 1,1,1
- Tris[(2-hydroxypropoxy)methyl]propane, dipropylene glycol, pentaerythritol, sorbitol, sucrose, lactose, alpha-methyl-glycoside, alpha-hydroxyalkyl glucoside, novolac resin, phosphoric acid, benzene phosphoric acid, polyphosphorus Acids such as tripolyphosphoric acid and tetrapolyphosphoric acid, ternary condensation products, caprolactone, etc. The alkylene oxides used to make polyoxyalkylene polyols usually have 2 to 4 carbon atoms.
Propylene oxide and mixtures of propylene oxide and ethylene oxide are preferred. The polyols mentioned can themselves be used as active hydrogen compounds. The preferred class of polyether polyols used in the present invention can be generally represented by the formula: R [(OC _o H _2o ) _z OH] _a [wherein R is hydrogen or a polyvalent hydrocarbon group; a is an integer equal to the valence of R (for example, from 1 or 2 to 6 to 8); Yes, any n
is an integer from 2 to 4 (preferably 3), and any z is from 2 to about 200, preferably 15
is an integer having a value between 100 and 100]. Other active hydrogen-containing materials are polymers of cyclic esters with reduced viscosities of at least about 0.15, preferably from about 0.2 to about 15 and higher.
Preferred cyclic ester polymers have a reduced viscosity of about
It has a value of 0.3 to about 10. These polymers are homopolymers or copolymers characterized by containing units of the formula: [wherein each R ₁ is individually hydrogen, alkyl, halo or alkoxy, A is an oxy group, and x
is an integer from 1 to 4, c is an integer from 1 to 4, b is an integer from 0 to 1, and x+c
+b is at least 4 and not greater than 6, and R ₁ groups include methyl, ethyl, isopropyl, n-butyl, sec-butyl, tert-butyl, hexyl, chloro, bromo, iodo, methoxy, ethoxy, n-butoxy, n-hexoxy, 2-ethylhexoxy, dodecoxy, etc.].
Preferably, each R ₁ is individually hydrogen; lower alkyl, such as methyl, ethyl, n-propyl, isobutyl; and/or lower alkoxy, such as methoxy, ethoxy, propoxy, n-butoxy, and the like. Furthermore, it is preferred that the total number of carbon atoms in the R ₁ substituent does not exceed 8. In one embodiment, preferred cyclic ester polymers contain both repeating structural units and repeating units of the formula: [wherein each R' is individually hydrogen, alkyl, cycloalkyl, aryl or chloroalkyl,
Alternatively, the two R' groups together with the ethylene portion of the oxyethylene chain of the unit contain 4 to 8 carbon atoms.
, preferably 5 to 6, and w is an integer of 1 or more, preferably 1 to 10]. Preferably, the repeat unit contains 2 to 12 carbon atoms. Examples of R' groups include: methyl, ethyl, n-propyl, isopropyl, tert-butyl, hexyls, dodecyls, 2-chloroethyl, phenyl, phenethyl, ethyl phenyl, cyclopentyl, cyclohexyl, cycloheptyl. Such. R' is preferably hydrogen; lower alkyl, such as methyl, ethyl, n-propyl, isopropyl; chloroalkyl, such as 2-chloroethyl. The repeating unit () is connected to the carbonyl group of the second unit through the oxy group (-O-) of one unit. It is connected with. In other words, this linkage is a direct bond between two carbonyl groups: Does not include. On the other hand, cyclic ester polymers with relatively low molecular weights, such as those with a reduced viscosity of about 0.3 or less, are characterized in that their terminal groups can be hydroxyl or carboxyl. Cyclic ester polymers having an average molecular weight of about 500 are preferred for use herein. The production of cyclic ester polymers is well supported in the patent literature, for example, US Pat. Nos. 3,021,309-3,021,317; US Pat. Simply stated, this method:
A mixture containing at least one cyclic ester monomer is polymerized with or without a functional polymerization initiator, such as the polyols described above or the polyols described in the patent specifications, and a suitable catalyst. The catalyst is selected depending on whether or not a polymerization initiator is present. Suitable cyclic monomers that can be used to make cyclic ester polymers are best represented by the following formula: [In the formula, R ₁ , A, x, c and b have the meanings given in the units above]. Typical cyclic ester monomers contemplated are, for example, delta-valerolactone; epsilon-caprolactone, zeta-enantholactone; monoalkyl delta-valerolactones, such as monomethyl-monoethyl- and monohexyl-delta-valerolactone. . In the absence of added functional polymerization initiators, the polymerization reaction is carried out under effective conditions and in the presence of an anionic catalyst, as described in U.S. Pat. desirable. When reacting a mixture of cyclic ester monomers and a functional polymerization initiator having at least one active hydrogen substituent, such as carboxyl or hydroxyl, U.S. Pat.
No. 2878236, No. 2890208, No. 3169945 and No.
It is desirable to use the catalysts described in each of the No. 3,284,417 specifications under the effective conditions discussed therein. Suitable polyol initiators and polycarboxylic acid initiators include those listed in U.S. Pat. It is a carboxyl compound. Cyclic ester polymers are also described in U.S. Pat.
It can be produced by the method described in No. 2962524. Cyclic ester/alkylene oxide copolymers also include cyclic ester monomers and alkylene oxide monomers, surfactants such as solid, relatively high molecular weight poly(vinyl stearate) or lauryl methacrylate/pinyl chloride copolymers. The mixture (equivalent viscosity in cyclohexanone at 30° C. from about 0.3 to about 1.0) is prepared in the presence of an inert, usually liquid, saturated aliphatic hydrocarbon vehicle, such as heptane, and phosphorus pentafluoride as a catalyst.
It can be prepared by reacting at an elevated temperature, for example about 80° C., for a sufficient time to form a cyclic ester/alkylene oxide copolymer. When a cyclic ester polymer is produced from a mixture containing a cyclic ester monomer and a small amount of a cyclic comonomer copolymerizable therewith, such as a cyclic carbonate and a cyclic ether, such as alkylene oxide, oxetane, tetrahydrofuran, etc. , the polymer chain of the resulting copolymer product comprises the repeating linear units and repeating linear units (which represent the alkylene oxide comonomer polymerized therein) and/or in the monomer mixture. characterized by repeating linear units corresponding to other polymerizable cyclic comonomers in When the comonomer is an alkylene oxide, the resulting copolymer product contains both repeating and repeating linear units in its copolymer chain. The connection between the linear units described above is a direct bond of two oxy groups, that is, -O-
It does not contain or occur O-. In other words, the oxy group (-O-) of the repeating linear unit is the carbonyl group of the repeating linear unit. or to the alkylene moiety of the second oxyalkylene unit (). The cyclic ester polymers described above are useful in making polyurethane products having relatively high strength and elongation. As mentioned above, the intended cyclic ester polymer is expressed by its reduced viscosity value. As is well known in the art, reduced viscosity values are a measure or indication of the molecular weight of a polymer. The term "equivalent viscosity" is the specific viscosity divided by the concentration of polymer in the solvent, measured in grams of polymer per 100 ml of solvent. The specific viscosity is obtained by dividing the difference between the viscosity of the solution and the viscosity of the solvent by the viscosity of the solvent. Unless otherwise specified, reduced viscosities as used herein are at a concentration of 0.2 g of polymer in 100 ml of solvent (e.g. cyclohexanone, benzene, chloroform, toluene or other common organic solvents).
Measured at 30℃. Another type of active hydrogen-containing material useful in the present invention is ethylenically inert in polyols, as described in British Patent No. 1,063,222 and US Pat. No. 3,383,351, which are incorporated herein by reference. It is a polymer/polyol composition obtained by polymerizing saturated monomers. Monomers suitable for making such compositions include acrylonitrile,
Vinyl chloride, styrene, butadiene, vinylidene chloride and other ethylenically unsaturated monomers are described in the aforementioned British and US patents. Suitable polyols include those mentioned above and those described in this British and US patent specification. The polymer/polyol composition contains from about 1 to about 70 monomers polymerized in the polyol.
% by weight, preferably from about 5 to about 50%, and most preferably from about 10 to about 40%. Such compositions are prepared by subjecting the monomers to a free radical polymerization catalyst, such as a peroxide, in a selected polyol at a temperature of 40°C to 150°C.
Conveniently, they are prepared by polymerization in the presence of persulfate, percarbonate, perborate and azo compounds. Details of this composition and method of manufacture are described in the aforementioned British and US patent specifications. The resulting composition is believed to be a complex mixture including free polyol, free polymer, and graft polymer/polyol complex. Preparation 1 of said British patent specification is particularly preferred. A mixture of the active hydrogen-containing compounds can be used as a reactant with a polyisocyanate to form a polyurethane. For example, mixtures of diols such as propylene glycol, polymer/polyol compositions and cyclic ester polymers can be used. Other examples of such mixtures include mixtures of polyether polyols;
Mixtures of polyols, dipropylene glycol and cyclic ester polymers; mixtures of polyether polyols, dipropylene glycol and polymer/polyols; mixtures of polyether polyols and dipropylene glycol, and the like. Preferably, the polyol is selected from castor oil, polybutadiene polyol and ethylene oxide terminated polyether polyol. The polyol is used with the isocyanate in an amount such that the isocyanate index is from about 70 to about 150, preferably from about 90 to about 120. Isocyanates suitable for use in the present invention have the following characteristics: liquid between about 20°C and about 40°C;
Viscosity less than about 2000 centipoise measured between about 20°C and about 40°C, functionality (NCO groups per molecule) equal to or greater than about 2; if polyol and catalyst are used, capable of curing at about 5°C to about 40°C to a film about 10 mils thick with no residual tack within about 5 hours;
Be miscible with the polyol by mixing for about 10 minutes at a temperature of 30 to about 40°C. The isocyanate includes any suitable polymeric isocyanate composition. This includes one or more such isocyanates. An example of a polymeric isocyanate is US Pat. No. 2,683,730 to Seeger et al., issued July 31, 1954.
No. 5,001,300, the entire disclosure of which is incorporated herein by reference. A typical polymeric isocyanate is of the following formula: [In the formula, R′ ₁ is hydrogen and/or lower alkyl,
Examples are methyl, ethyl, propyl and butyl]. Preferred polymeric isocyanates defined by the formula are those in which n' ranges from 2.1 to 4.0 and R' ₁ is hydrogen and/or methyl. A particularly preferred polymeric isocyanate is polymethylene polyphenyl isocyanate (ie, in the formula R' ₁ is hydrogen), which is commercially available under the trademark "PAPI". These are usually supplied in the form of polyisocyanate mixtures with an average NCO functionality of 2.2 to 3.5, and more commonly 2.3 to 3.0. Of course, the terms "polymeric isocyanate" and "polymethylene polyphenyl isocyanate" as used herein encompass mixtures containing one or more such polyisocyanates. Further details regarding polymeric isocyanates and their preparation are provided in the Seeger et al. patent, supra. Also suitable for use herein are 2,4- and 2,6-toluene diisocyanates and mixtures thereof. Liquid methylene bis(phenyl isocyanate) described in US Pat. No. 3,384,653; 4,
4′-methylenebis(phenyl isocyanate);
2,4'-methylene bis(phenyl isocyanate); mixture of 4,4'- and 2,4'-methylene bis(phenyl isocyanate); crude 4,4'-methylene bis(phenyl isocyanate); isomers of xylene isocyanate and mixtures thereof; each isomer of phenylene diisocyanate and mixtures thereof;
Isomers of naphthalene diisocyanate and mixtures thereof; substituted methylene bis(phenyl isocyanate) (substituents include, for example, 3-alkoxy, 3,
3'-dimethyl and 3,3'-dimethoxy); substituted 2,6-toluene diisocyanates [substituents include p-methoxy, pi-propyl, p-
CN, p-methyl, p-CO-alkyl, p-N
(alkyl) ₂ ]; halogenated isocyanate,
For example, monochloro 2,4-toluene diisocyanate, monochloro 2,6-toluene diisocyanate; terphenyl isocyanate: for example 4,4',4''-triisocyanatometa-terphenyl;4,4'-diisocyanate diphenyl oxide, 4,4 '-diisocyanatodiphenyl sulfide, 4,4'-diisocyanatodiphenylethylene-1,2,4,4'-diisocyanatonaphthalene disulfide and 4-isocyanatophenylsulfonylisocyanate; aliphatic Isocyanate:
For example, 3-isocyanatomethyl-3,5,5-
Trimethylcyclohexyl isocyanate; 1,
6-hexamethylene diisocyanate; 1,4-
Tetramethylene diisocyanate; 1,4-butylene (-2-) isocyanate; diisocyanatocyclohexane; triisocyanatocyclohexane, norbornane diisocyanate described in U.S. Patent Nos. 3493330 and 3470248; U.S. Patent No. 357942 Bis(2-isocyanatoethyl) fumarate described in US Pat. No. 3,370,077
Dimerized fatty acid diisocyanates described in U.S. Pat. No. 3,455,883; U.S. Pat.
1,2-bis (p-
(2-isocyanatoethyl)phenyl-1-isocyanatomethylethane; 1,4-bis(isocyanato)-1 described in U.S. Pat. No. 3,455,981
-Phenyltetrahydronaphthalene; hydrogenated aryl isocyanates, such as 2,4-(p-isocyanatocyclohexylmethylene)-1-isocyanatocyclohexane; 4,4'diisocyanatodicyclohexylmethane; 2,3-bis(difluoroamino) -1,4-diisocyanatobutane;
4,4'-bis(2-isocyanatohexafluoropropyl)diphenyl oxide; U.S. Patent No.
Acylated urea polyisocyanates as described in U.S. Pat. No. 3,383,400; Biuret polyisocyanates as described in U.S. Pat.
Silicon-containing polyisocyanates as described in US Pat. No. 3,519,579. Prepolymers derived from the following can also be used in the present invention: the aforementioned diisocyanates and glycols in a molar ratio of about 3:
greater than 1; the diisocyanate and polyol having an NCO:OH molar ratio of about 7:
1; the above-mentioned polymeric isocyanate and polydiol having an NCO:OH ratio of about 7:1 or greater. In the present invention, polymeric isocyanates are preferred.
This is due to the following reason. i.e. low viscosity;
Low vapor pressure; sufficient compatibility with polyols; flame retardancy due to aromatic structure; high rigidity and strength due to aromatic structure; low price and low toxicity. More preferred are polymeric isocyanates with a high ortho content because they are more miscible with polyols and have better color than polymeric isocyanates with a high para content. Isocyanates, together with polyols, NCO:
OH molar ratio is about 0.70:1.50, preferably about 0.9:
Used in 1.20. Any thixotrope can be used in the compositions of the invention. For example, colloidal silica, hydrogenated castor oil, bentonite clay, etc. A preferred thixotrope is hydrogenated castor oil. The amount of thixotrope used is approximately 1 per 100 parts of polyol by weight.
from about 15 parts, preferably from about 2 to about 10 parts. When using a catalyst in the composition, various urethane producing catalysts can be used. Catalysts having the following properties are preferred. i.e. high activity for the reaction between isocyanates and organic hydroxyl groups; low activity for the reaction between isocyanates and water; high solubility in polyols; viscosity increase after mixing the catalyst into the foam. can be significantly retarded; at temperatures of about 5°C to about 40°C, the catalytic effect is briefly delayed (from about 30 seconds to about 120°C).
second delay times are preferred); high solubility in diluents. These catalysts include: dialkyltin carboxylates such as dibutyltin dilaurate, dioleate, diacetate, or di-2-ethylhexoate; dimethyltin dithiolaurate, stannous octoate, Stannous oleate, potassium octoate, potassium acetate, phenylmercuric propionate, iron () acetylacetonate, copper () acetylacetonate, zinc octoate, zinc acetate, cobalt acetate (), manganese acetate (), isopropyl titanate, tri acrylic isopropyl titanate,
Lead naphthanate, cobalt naphthanate, bismuth nitrate, iron chloride (), sodium silicate, aluminum acetylacetonate, zinc acetylacetonate, nickel () acetylacetonate, methyl titanate and zinc stearate. Particularly effective catalysts are those with tin-sulfur bonds, such as dibutyltin sulfide, and dialkyltin dithiodialkylidene diesters of the formula: [wherein R ₂ and R ₃ are independently 1 to about 20 carbon atoms]
alkyl, arylalkyl and alkylaryl, d is an integer from 1 to 8, and d' is an integer from 1 to 10]. In the above formula, preferably R ₂ and R ₃ are 1 to 8 carbon atoms.
alkyl, and d is an integer from 1 to 4. Tertiary amines can also be used as catalysts. These tertiary amines can be represented by the following formula: [In the formula, R ₆ , R ₇ and R ₈ are independently aryl, alkylaryl, arylalkyl, alkyl,
cycloalkyl, alkenyl groups (wherein aryl, alkylaryl and arylalkyl groups contain about 6 to about 20 carbon atoms; alkyl groups contain 6 to 18 carbon atoms; alkenyl (containing about 3 to 18 carbon atoms) and saturated 5- and 6-membered heterocyclic groups containing 1 to 3 nitrogen atoms, where a' is an integer from 1 to 5; be〕. [In the formula, R ₉ , R ₁₀ and R ₁₁ are independently,

[Formula] or an optionally substituted monofunctional hydrocarbon group, provided that at least one of R ₉ , R ₁₀ or R ₁₁ is

[Formula] where R ₉ and R ₁₀ are selected from C ₁ -C ₆ alkyl, C ₂ -C ₆ hydroxyalkyl, and e is from 0 to 10. Examples of optionally substituted hydrocarbon groups include morpholinoalkyl; piperidinoalkyl;
Alkylaminoalkyl; hydroxyalkyl;
Mention may be made of alkoxyalkyl and alkylcarbonyloxyalkyl. These triazine-containing compounds are described, for example, in U.S. Pat.
It is known in the art, as shown in US Pat. No. 3,884,917. Amines suitable for use in the present invention include: triethylenediamine, N,N-
Dimethylcyclohexylamine, triethylamine, N-ethylmorpholine, N-methyl-2,2
-Dialkyl-1,3-oxazolidine, N-alkylpiperazine, N,N'-dialkylpiperazine, tetramethyl-1,3-butanediamine,
Dimethylethanolamine, bis-dimethylamino diethyl ether, imidazole, N, N',
N″-tris(3-dimethylaminopropyl)-
S-hexahydrotriazine. It is also possible to use mixtures of the aforementioned catalysts. The catalyst is 0.01 based on the weight of the polyol.
It is used in amounts as low as 0.50 parts by weight. The amount of catalyst used depends on the temperature of the foam into which the catalyst is injected, the amount and alkalinity of filler present, the reactivity of the polyol, and the temperature of the substrate to which the foam is applied. For example, the temperature of the foam is approximately 40°C and the temperature of the substrate (e.g. wall panel) is approximately
At 25°C, a catalyst such as dialkyltindithioalkylidene is used in an amount of only about 0.1 part. If the foam temperature is below about 40°C and the substrate temperature is below about 25°C, use greater than 0.1 parts by weight of catalyst per 100 parts of polyol, and even higher amounts such as 0.50 parts by weight. is possible. Catalysts are generally added in a solvent. This solvent can be selected from a wide variety of substances. The solvent may be, for example, a polyol or polyamine as described above, or a surfactant as described below, or a plasticizer such as a dialkyl phthalate. Generally, the catalyst is dissolved in about 10 to about 100 parts of solvent per part of catalyst. The catalyst can be mixed with a solvent and this mixture added to and mixed with the foam foam. When the catalyst is added in this manner, it is dissolved in the solvent. This indicates the preferred method of adding catalyst. Alternatively, relatively large amounts of catalysts insoluble in the polyol, such as bismuth-containing and silicate-containing catalysts, especially Bi(NO ₃ ) ₃ and Na ₂ SiO ₃ , are mixed into the polyol and subsequently ethylene glycol, Simple glycols such as propylene glycol, or glycerin, or mixtures thereof can be added for solubilization. Since the catalyst is insoluble in the polyol,
No gelation occurs in the hose applying the foam. If the catalyst is dissolved in the polyol and added to the polyol package, gelation will occur within the processing equipment and block it. Compositions of the invention may optionally contain one or more of the following ingredients: surfactants,
Moisture removers, fillers, flame retardants, dyes, pigments, etc. Preferably, the surfactant is an organosilicon copolymer described in, for example, US Pat. No. 3,772,224 and US Pat. No. 4,022,722. Other organosilicon surfactants are partially crosslinked siloxane-polyoxyalkylene block copolymers and mixtures thereof, where the siloxane and polyoxyalkylene blocks are bonded by silicon-carbon bonds or silicon-oxygen-carbon bonds. has been done. The siloxane blocks consist of hydrocarbon-siloxane groups and have at least two silicon valences per block attached to the bonds. At least a portion of the polyoxyalkylene block consists of oxyalkylene groups and is a polyatomic group. That is, each block bonded to the bond has at least two valences of carbon and/or oxygen bonded to carbon. The remaining polyoxyalkylene block consists of an oxyalkylene group and is monovalent. That is, each block attached to the bond has only one valence of carbon or oxygen bonded to carbon. Additionally, conventional organopolysiloxane polyoxyalkylene block copolymers, such as U.S. Pat.
Those described in the specifications of No. 2917480 and No. 3957901 can be used. Other surfactants that can be used in the present invention are:
U.S. Pat. No. 4,022,722, incorporated herein by reference.
A high molecular weight linear non-hydrolyzable (AB) _siloxane -polyoxyalkylene block copolymer as described in No. These block copolymers described in U.S. Pat. No. 4,022,722 have the following average formula: [In the formula, R ₁₄ and R' ₁₄ independently represent a monovalent hydrocarbon group containing no aliphatic unsaturation, and n is 2 to 4.
is an integer of at least 6, and c′ is an integer of at least 6;
f is an integer of at least 4, g is an integer of at least 4, B represents a divalent organic group bonded to the adjacent silicon atom by a carbon-silicon bond and to the polyoxyalkylene block by an oxygen atom; However, one Y group is present in the molecule], and the average molecular weight of each siloxane block is about 500 to about 10,000; the average molecular weight of each polyoxyalkylene block is about 300 to about 10,000; About 20 to about 50 of the copolymer
the polyoxyalkylene blocks constitute from about 80 to about 50 percent by weight of the copolymer; and the average molecular weight of the block copolymer is at least about 30,000. Surfactants can be used in amounts of 1 to about 10, preferably about 1 to about 4 parts by weight per 100 parts of polyol. Hygroscopic materials that can be used in the present invention include: molecular sieves of the zeolite type, silicates such as ethyl silicate, oxazolidines, carbodiimides, inorganic materials such as magnesium sulfate, sulfuric acid. Calcium, calcium chloride and any other inorganic salts that can be hydrated with water. Molecular sieves are preferred. The hygroscopic material can be used in an amount of about 1 to about 15, preferably about 3 to about 7 parts by weight per 100 parts of polyol. Suitable fillers that can be used include, for example, barium sulfate, calcium carbonate, alumina trihydrate, and the like. Fillers with low hygroscopicity are preferred. In the present invention, the filler can have a catalytic effect. Fillers can be used in amounts up to about 250 parts by weight, preferably from about 100 to about 200 parts by weight per 100 parts of polyol. Flame retardants can be added to the composition if it is desired to produce a flame retardant cured polyurethane foam. Suitable flame retardants include alumina trihydrate;
Phosphorus-containing compounds, including, for example, tricresyl phosphate; halogenated phosphates, including, for example, tris(dichloropropyl) phosphate. In the practice of this invention, the density of the uncured foam is from about 18 to about 45 lbs./ft ³ . The density of the foam is approximately equal to the density of the foamed polyurethane formed. The selection of the components of the composition is based on the amount of water in the composition.
The composition is cured to less than the amount that will result in a foamed polyurethane having a density that is not substantially the same as the density of the foamed composition. The composition of the present invention forms a foamed polyurethane that is essentially free from secondary foaming. The moisture content of the composition can be made as low as possible by ensuring that each component does not introduce significant amounts of moisture into the composition. This is achieved, for example, by choosing a polyol with the lowest possible average hydroxyl number (low hygroscopicity) and by choosing an isocyanate that can be cured with the polyol in the shortest possible time. A urethane forming catalyst can be added to speed up the curing rate. If a high hydroxyl number or highly hygroscopic polyol is chosen, a hygroscopic material can be added to the composition. Thus, it can be seen that by relating the components, a composition with the lowest water content is obtained. Although the following examples specifically illustrate the practice of the invention, they are not intended to limit the scope of the invention in any way. In the examples below, foams were produced using the equipment shown in FIGS. 1 and 2. Example 1 57.7 pounds of castor oil, 14.4 pounds of a propylene oxide adduct of an 80/20 mixture of sorbitol and propylene glycol, the polyol having a hydroxyl number of 490, 4.3 pounds of thixotropic, or hydrogenated castor oil, of the formula ( AB) _o (hereinafter referred to as surfactant A), where A is a block of dimethyl silicone units, B is a block of oxyalkylene units, and n is greater than 20. , 3.6 pounds of 3A molecular sieve and 72.1 pounds of trihydrated alumina 2,2-dichloro-1,3-
Propanediyltetrakis (2-chloroethyl)
A polyol package was prepared by mixing 72.2 pounds of phosphate flame retardant in a sealed one gallon container under a nitrogen atmosphere. The ingredients were mixed until the temperature reached 60°C, at which point it was cooled under a nitrogen atmosphere. The material is then heated under pressure with nitrogen (approximately 30 to
70psi back pressure) was fed into an SKG continuous mixer. Nitrogen was fed into the polyol tube just before the stream entered the continuous mixer. A stoichiometric amount of liquid polymethylene polyphenyl isocyanate was also pumped through another conduit into the continuous mixer by a Zenith metering pump. The resulting foam was passed through a static mixer (Stata Tube) through an 8 foot long 1/2 inch ID hose.
20-65, 3/4 inch apparent diameter, 221/2 inches long]. Immediately before the static mixer, in a polyol consisting of a propylene adduct of glycerin having a hydroxyl number of 240, the formula A catalyst which is a dialkyl dimercaptide carboxylic acid ester having the formula [wherein R ₂ and R ₃ are -CH ₃ , n is equal to 2, and m is an integer from 1 to 10] [UL-24. Witco Chemical Company
Chemical Company] was injected using a micro-metering pump at a rate that provided 0.1 weight of catalyst per 100 parts of polyol. The catalyst was dispersed into the foam by passing through the static mixer. The catalyzed foam was deposited onto the wallboard joint and spread with a steel blade to form a smooth seam. The density of the foam was 32 pounds per cubic foot. The seamed joints were cured vertically at a temperature of 26°C and 90% relative humidity. No sagging or secondary foaming of the seams occurred. The foam reached the gelling stage within 33 minutes and a blade could be drawn over the surface within 45 minutes without damaging the surface. Example 2 A polyol package was capped with ethylene oxide to increase the hydroxyl value.
A polyol consisting of a propylene oxide adduct of glycerin with a hydroxyl number of 30 and 27
The procedure of Example 1 above was repeated, except that it was prepared with: . A foam was prepared according to the procedure described in Example 1 above. depositing the foam onto the wallboard joint;
A steel blade was spread over the joint to form a smooth seam. The density of the foam was 32 pounds per cubic foot. The spliced joints were cured vertically at a temperature of 26° C. and 90% relative humidity. No seam sagging or secondary foaming occurred. The foam is 28
The gelation stage was reached within minutes and the blade could be drawn over the surface without damaging it within 50 minutes.

[Brief explanation of the drawing]

FIG. 1 is a flow diagram overview of a preferred embodiment of the invention. FIG. 2 is a side view of containers 29 and 30 of FIG.

Claims (1)

Claims: 1. Separate sources of polyol, isocyanate, catalyst and inert gas; said polyol, isocyanate and inert gas separately and under pressure at controlled flow rates from said sources; means including separate conduits feeding a mixing device having inlet openings for receiving said polyol, isocyanate and inert gas; means for mixing said polyol, isocyanate and inert gas to produce a foam; and an outlet opening for the foam obtained; means for conveying the foam from the mixing device to a second mixing device;
a conduit for supplying catalyst under pressure at a controlled flow rate to said second mixing device; means for mixing said foam and catalyst; said mixing device mixing said foam and catalyst; said means having an inlet opening for receiving and an outlet opening for the produced catalyzed foam; and means for delivering said catalyzed foam from said mixing device onto a substrate. An apparatus for continuously producing a curable polyurethane foam, characterized in that: 2. The device of claim 1, wherein the source of polyol is a container containing a piston that creates pressure on the polyol. 3. Apparatus according to claim 1, including a source of solvent and means for supplying said solvent under pressure to a mixing device. 4. Apparatus according to claim 3 for maintaining the solvent under pressure in the source.