CA2119570A1 - Stable melamine dispersions in polymer polyols and polyurethane foam therefrom - Google Patents
Stable melamine dispersions in polymer polyols and polyurethane foam therefromInfo
- Publication number
- CA2119570A1 CA2119570A1 CA002119570A CA2119570A CA2119570A1 CA 2119570 A1 CA2119570 A1 CA 2119570A1 CA 002119570 A CA002119570 A CA 002119570A CA 2119570 A CA2119570 A CA 2119570A CA 2119570 A1 CA2119570 A1 CA 2119570A1
- Authority
- CA
- Canada
- Prior art keywords
- melamine
- polymer
- particle size
- dispersion
- percent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/63—Block or graft polymers obtained by polymerising compounds having carbon-to-carbon double bonds on to polymers
- C08G18/632—Block or graft polymers obtained by polymerising compounds having carbon-to-carbon double bonds on to polymers onto polyethers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/38—Low-molecular-weight compounds having heteroatoms other than oxygen
- C08G18/3819—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen
- C08G18/3842—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen containing heterocyclic rings having at least one nitrogen atom in the ring
- C08G18/3851—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen containing heterocyclic rings having at least one nitrogen atom in the ring containing three nitrogen atoms in the ring
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/409—Dispersions of polymers of C08G in organic compounds having active hydrogen
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/34—Heterocyclic compounds having nitrogen in the ring
- C08K5/3467—Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
- C08K5/3477—Six-membered rings
- C08K5/3492—Triazines
- C08K5/34922—Melamine; Derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G2110/00—Foam properties
- C08G2110/0008—Foam properties flexible
Abstract
This invention relates to the preparation of stable melamine dispersions in a polymer polyol. Stable dispersions of melamine particles having a mean particle size of from 10 to 125 microns in a continuous phase preferably comprising an SAN type polymer polyol and an inorganic particulate solid having an average particle size of from 5 to 30 nanometers are disclosed. The stable melamine dispersions are useful in the manufacture of combustion-modified flexible polyurethane foam.
Description
7 a STABLE MELAMINE DISPERSIONS IN POLYMER POLYOLS AND POLYURETHANE FOAM
THEREf ROM ~ ~ t This invention relates to a stable dispersion of melamine in a polymer polyoi and 5 the preparation of a polyurethane foam therefrom.
Polyurethane, by nature of being an organic polymer when subjected to suffi-cient heat in an oxygen- containing environment will burn. For many applicaticns it is desirable to reduce or retard the burning characteristics of such polymer by incorporating a flame retar-dant Commonly employed flame retardants for this purpose include phosphorus and/or .-10 halogen-containing compounds such as, for example, tris(chloroethyl)phosphonate (TCEP) and dimethoxymethyl phosphonate (DMMP) As an alternative to halogen and/or phosphorus-containing flame retardants, certain nitrogen-contain~ng compounds, notably meiamine, may be'used to prepare combustion-modified polyurethanes.
U.S. Patents 4,221,875; 4,258,1~1 and 4,826,844 describe the incorporation of me-15 lamine into foams for imparting resistant to smoldering combustion and flaming combustion.U S. Patent 4,892,893 discloses use of melamine, present in an amount of from 5 to 25 percent based on total weight of the flexible foam, having a mean particle size of from 25 to SOO mi-crometers, and to impart resistance to cigarette smoldering ignition of flexible polyurethane foam. According to these patents, the melamine is incorporated into ~he polyol immediately 20 prior to the manufacture of the foam. If not used almost immediately the melamine has a ten-dency to sediment out giving rise to processing problems. Melamine deposits accumulated via such sedimentation are frequently of a solid cement like nature and generally cannot be redis~
persed.
U S. Patent 4,293,697 discloses a stabilized dispersion of melamine in a polyether 25 polyol and its use in preparing a flexible polyurethane foam. At least 90 percent of the me-lamine particles have a mean size of less ~han 10 micrometers and are stabilized as a dispersion in the polyol by the presence of silicic acids and silicates, salts of perfluorinated alkyl carboxylic acids, salts of alkyl sulfonic acids and perfluorinated alkyl sulfonic acids, polyperfluorate polyols ~ :
and salts of aliphatic alcohol sulphates. Small melamine particle size is not favorable for use SUB~Tl~T~ ~HEET
- ~ 3 ~
where a high loading of melamine in the foam is required to pro\~ide the desirable degree of ~ ~:
flame retardation~ High loadings of small particle sized melamine frequently result in poor quality or unstable foams.
U.S. Patent 4,644,015 discloses stabilized dispersions of melamine in standard S polyether po!yols for use in preparing flexible polyurethane foam. The melamine particles, having a mesh size of greater than 325 that is less than 45 micrometers, being stabilized by the ~ ;.
presence of an amine compound consisting of diethanolamine, ethanolamine or trihexylamine.
The presence of such amine compound in the amounts re~uired to provide a stabilized disper~
sion is not desirable when preparing polyurethane foam especially in the presence of water.
10 Such amine compounds possess catalytic properties leading to system reactivities which are ~oo .-~
quick formanycommercial foamproducers.
The furniture industry, for example, desires foams exhibiting enhanced load bear-ing properties. A convenient means of achieving the desirable load bearing characteristics of flexible foam is to use a filler or polymer polyol in its preparation. Polymer polyols are distin~
15 guishable from conventional polyether polyols in that they have suspended therein a discrete ` ~
organic polymer. Illustrative of polymer polyol types are those wherein the suspended organic -polymer is a styrene:acrylonitrile (SAN) copolymer, a polyu-ea ad~lucl(PHD), a polyisocyanate- ;~
polyamine adduct ~PIPA) or an epoxy resin. In patent publication GB 2,163,762, dispersio~s of -melamine in polyhydra~odkarbonamide and/or polyurea polymer polyols are disclosed. The 20 publication is silent with respect to melamine particle size and storage stability of such disper-sions. The preparation of flexible polyurethane foam from styrene:acrylonitrile (SAN) copoly-rl er polyol-melamine dispersions is disclosed in U.S. Patent 4,745,133 wherein such dispersions are disclosed as containing uncrushed melamine and characterized by the absence of a stabiliz~
ing agent. ` ; ~-The immediate processing of a polyol containing melamine dispersed therein is not always possible and therefore it would be desirable to provide melamine/polyol formula-tions which are stable dispersions. for the purpose of using such dispersions in the préparation of flexible polyurethane foam having attractive physical characteristic including loading bear-ing properties it would be desirable to provide for a stable dispersion of melamine in a polymer 30 polyol.
In a first aspect, this invention is a stable melamine-polyether polyol dispersion in the presence of an inorganic particulate solid characterized in that~
(a) the polyol is a polymer-modified polyether polyol or mixture thereof which contains from 4 to S0 weight percent of ar. organic polymer solid;
35 (bJ the melamine, present in from 20 to 60 percent based on total weight of (a) and (b), has a mean particle size of from at least 25 and up to 125 micrometers; and (c) the inorganic particulate solid, present in from 0.2 tO 5 percent based on the total weight of (a) and (b), is a silicic acid or a fumed silicic acid which has an average particle size of from S tO
30 nanometers ~SUB~;TI~TE St lEET
THEREf ROM ~ ~ t This invention relates to a stable dispersion of melamine in a polymer polyoi and 5 the preparation of a polyurethane foam therefrom.
Polyurethane, by nature of being an organic polymer when subjected to suffi-cient heat in an oxygen- containing environment will burn. For many applicaticns it is desirable to reduce or retard the burning characteristics of such polymer by incorporating a flame retar-dant Commonly employed flame retardants for this purpose include phosphorus and/or .-10 halogen-containing compounds such as, for example, tris(chloroethyl)phosphonate (TCEP) and dimethoxymethyl phosphonate (DMMP) As an alternative to halogen and/or phosphorus-containing flame retardants, certain nitrogen-contain~ng compounds, notably meiamine, may be'used to prepare combustion-modified polyurethanes.
U.S. Patents 4,221,875; 4,258,1~1 and 4,826,844 describe the incorporation of me-15 lamine into foams for imparting resistant to smoldering combustion and flaming combustion.U S. Patent 4,892,893 discloses use of melamine, present in an amount of from 5 to 25 percent based on total weight of the flexible foam, having a mean particle size of from 25 to SOO mi-crometers, and to impart resistance to cigarette smoldering ignition of flexible polyurethane foam. According to these patents, the melamine is incorporated into ~he polyol immediately 20 prior to the manufacture of the foam. If not used almost immediately the melamine has a ten-dency to sediment out giving rise to processing problems. Melamine deposits accumulated via such sedimentation are frequently of a solid cement like nature and generally cannot be redis~
persed.
U S. Patent 4,293,697 discloses a stabilized dispersion of melamine in a polyether 25 polyol and its use in preparing a flexible polyurethane foam. At least 90 percent of the me-lamine particles have a mean size of less ~han 10 micrometers and are stabilized as a dispersion in the polyol by the presence of silicic acids and silicates, salts of perfluorinated alkyl carboxylic acids, salts of alkyl sulfonic acids and perfluorinated alkyl sulfonic acids, polyperfluorate polyols ~ :
and salts of aliphatic alcohol sulphates. Small melamine particle size is not favorable for use SUB~Tl~T~ ~HEET
- ~ 3 ~
where a high loading of melamine in the foam is required to pro\~ide the desirable degree of ~ ~:
flame retardation~ High loadings of small particle sized melamine frequently result in poor quality or unstable foams.
U.S. Patent 4,644,015 discloses stabilized dispersions of melamine in standard S polyether po!yols for use in preparing flexible polyurethane foam. The melamine particles, having a mesh size of greater than 325 that is less than 45 micrometers, being stabilized by the ~ ;.
presence of an amine compound consisting of diethanolamine, ethanolamine or trihexylamine.
The presence of such amine compound in the amounts re~uired to provide a stabilized disper~
sion is not desirable when preparing polyurethane foam especially in the presence of water.
10 Such amine compounds possess catalytic properties leading to system reactivities which are ~oo .-~
quick formanycommercial foamproducers.
The furniture industry, for example, desires foams exhibiting enhanced load bear-ing properties. A convenient means of achieving the desirable load bearing characteristics of flexible foam is to use a filler or polymer polyol in its preparation. Polymer polyols are distin~
15 guishable from conventional polyether polyols in that they have suspended therein a discrete ` ~
organic polymer. Illustrative of polymer polyol types are those wherein the suspended organic -polymer is a styrene:acrylonitrile (SAN) copolymer, a polyu-ea ad~lucl(PHD), a polyisocyanate- ;~
polyamine adduct ~PIPA) or an epoxy resin. In patent publication GB 2,163,762, dispersio~s of -melamine in polyhydra~odkarbonamide and/or polyurea polymer polyols are disclosed. The 20 publication is silent with respect to melamine particle size and storage stability of such disper-sions. The preparation of flexible polyurethane foam from styrene:acrylonitrile (SAN) copoly-rl er polyol-melamine dispersions is disclosed in U.S. Patent 4,745,133 wherein such dispersions are disclosed as containing uncrushed melamine and characterized by the absence of a stabiliz~
ing agent. ` ; ~-The immediate processing of a polyol containing melamine dispersed therein is not always possible and therefore it would be desirable to provide melamine/polyol formula-tions which are stable dispersions. for the purpose of using such dispersions in the préparation of flexible polyurethane foam having attractive physical characteristic including loading bear-ing properties it would be desirable to provide for a stable dispersion of melamine in a polymer 30 polyol.
In a first aspect, this invention is a stable melamine-polyether polyol dispersion in the presence of an inorganic particulate solid characterized in that~
(a) the polyol is a polymer-modified polyether polyol or mixture thereof which contains from 4 to S0 weight percent of ar. organic polymer solid;
35 (bJ the melamine, present in from 20 to 60 percent based on total weight of (a) and (b), has a mean particle size of from at least 25 and up to 125 micrometers; and (c) the inorganic particulate solid, present in from 0.2 tO 5 percent based on the total weight of (a) and (b), is a silicic acid or a fumed silicic acid which has an average particle size of from S tO
30 nanometers ~SUB~;TI~TE St lEET
3~, 780-F
9 ;~
In a second aspect, this invention is a process for preparing a stable dispersion as described in the first aspect.
In a third aspect, this invention is a polyurethane polymer obtainable by contact-ing under reaction conditions an organic isocyanate with an isocyanate reactive composition 5 which contains a stable dispersion as claimed in Claim 1 wherein the organic polyisocyanate is present in an amount to provide from 0.85 to about 1.25 isocyanate groups per isocyanate reac-tive hydrogen atom present characterized in that the polymer has dispersed, based on total weight of polymer, therein: from 2 to 30 percent of melamine that has a mean particle size of from at least 25 and up to 125 micrometers; from 0.1 to 2.5 percent of an inorganic particulate 10 solid being a silicate, a silicic acid or a fumed silicic acid which has an average particle size of from S to 30 nanometers; and from 2 to 25 percent of an organic polymer solid.
Surprisingly, such above-described melamine polymer polyol dispersions are sta-ble. Additionally, such stabilized dispersions can be conveniently processed to provide flexible polyurethane foam exhibiting desirable combustion-modified characteristics and overall com-15 mercially attractive physical properties.
The stable dispersion of this invention has a continuous phase comprising a polyolhaving suspended therein an organic polymer solid and having further dispersed therei n m~-lamine particles and an inorganic particulate solid (sometimes referred to hereinafter as IPS).
By "stable" it is understood that when the dispersion is stored at room temperature, without 20 agitation, the melamine essentially remains dispersed in the continuous phase with little or no sedimentation being observed. If sedimentation should occur the dispersion of this invention may be characterized in that only a minimum of effort is required to redisperse the melamine due to the presence of the IPS. Generally little or no melamine sedimentation will occur within the first 2 weeks after preparation of the dispersion. Depending on the amount of IPS present, 25 frequently little or no melamine sedimentation may occur in the first 12 or even first 20 weeks after preparation of the dispersion.
The continuous phase of the stable dispersion comprises a polyether polyol or mixture of polyether polyols containing from 4 to S0 weight percent of a polymer solid. Prefer-ably such polyol contains the polymer solid in an amount of from 4 to 30, more preferably from 30 5 to 2~ percent. Polyol containing a higher solids content than this will generally be highly vis-cous and difficult to manage; a lower solids content normally will not provide for any notice-able effect when incorporated into a polyurethane polymer. A polyether polyol containing such solid is generally referred to as a "polymer polyol". To provide for a continuous phase having such a polymer solids content as mentioned hereinabove, advantageously the continu-35 ous phase comprises such a polymer polyol in an amount of at least S0, pre-ferably at least 60, and more preferably at least 75 weight percent of the continuous phase. When the continuous phase is not constituted in its entirety by the polymer polyol the remaining percentage may be constituted by other conventional polyoxyalkylene polyols used S~ g~ f 3S,7~0-F
- 211~ ~7~3 in the p!eparation of polyurethane polymers. Suitable polyols containing an organic polymer solid for use in this present invention include SAN-, PHD- and PlPA-type polymer polyols. Pro-cesses for obtaining suitable PHD- and PlPA-type polymer polyols are disclosed in U.S. Patents 4,374,209; 3,325,421; 4,042,537 and 4,093,567. Processes for obtaining suitable SAN copolymer polyols for use in this present inYention are described in U.S. Patents 3,385,351; 3,304,273;
3,523,093 and 3,110,695.
When using the stable dispersion for the preparation of flexible polyurethane foams it is advantageous if the polyol of the continuous phase has an average of from 2 to 4 isocyanate-reactive groups per molecule; an average hydroxyl equivalent weight of from 750 .~ 3000, preferably at least 1000, more preferably at least 1200; and preferably ~t most 2500, more preferably at most 2000. Additionally it is advantageous for the polyol to have a primary hydroxyl content of from at least 10, preferably ~rom at least 30, and more preferably from at least 50 percent of its total hydroxyl content. Use of a polyol having such characteristics gener-ally provides for a flexible polyurethane foam with desirable physical properties. In a preferred 15 embodiment of this invention the continuous phase comprises a SAN polymer polyol, and more p-eferably consists essentially of a SAN polymer polyol. Exemplary of sui table commercially available SAN polymer polyols include those sold by The Dow Chemical Company and include the products designated as VORANOL ~ CP-8020, VORANOL ~ CP-8010, VORANOL'~ CP-8030, and products designated as VORALUX'~ in conjunction with the designation codes HN200 20 through ~o HN206.
The melamine dispersed within the continuous phase is characterized ir that it has an average particle size of frorn 25 to 125 micrometers. The melamine particle size is pref-erably at least 40 and more preferably at least 50 micrometers, and preferably at most 100, more preferably at most 90 micrometers. Melamine having such a particle size is readily avail-25 able commercially and may be obtained and used directly without the need for particle size re-duction through milling, grinding or such like techniques. Use of melamine having a smaller particle size than defined provides mixtures whose viscosity is undesirably high for convenient processing and preparation of polyurethane foam. Use of melamine having an average parti-cle size significantly greater than d~fi ned above is not desirable as when present i n a foami ng 30 process poor quality or collapsed foam may resu!t. The stable dispersion of the present inven-tion comprises the melamine in an amount sufficient to provide for the desired combusti~n modification of flexible polyurethane foams prepared therefrom. The dispersion comprises the melamine in an amount of from 20 to 60, preferably at least 25, and more preferably at least 30, and preferably at most 55, more preferably at most 50, and most preferably at most 35 35 weight per~ent based on total weight of melamine and polyol including polymer solids. When the melamine has a small particle size generally it will be present in a smaller amount than when having a larger particle size.
: 8,~8~
r) o The stability of the melamine dispersed in the continuous phase is provided for by the presence of an inorganic particulate solid (IPS) that has an average particle si~e of from 5 to 30 nanometers. Preferably, the IPS has an average particle size of from S to 20, and more pref-erably from ~ to 14 nanometers. The IPS is present in an amount of from 0.2 to 5, preferably at S least 0.25, more preferably at least 0.5, and preferably at most 3.0, more preferably at most 2.0 percent based on the total weight of rr~elamine and polyol including polymer solids present.
Greater amounts of the IPS generally providing for enhanced storage stability characteristics of the dispersion and ability to redisperse the melamine should any sedimentation occur. Suitable IPS substances for use in the present invention include hydrophilic substances compatible with 10 processes for the preparation of polyurethane polymers such as silicates or especially silicic acids and particularly fumed silicic acids. Exemplary of preferred silicic acid products for use in this present in~ention include substances designated as A~ROSIL'~ 200, Af ROSlL'~ 300 and AERO-SIL'~ 380 available from Degussa GmbH, Germany.
Optionally when preparing the dispersions of this invention a dispersing aid may15 be present. When present, the dispersinS~ aid advantageously is used in an amount of from 0.25 to 1.5, preferably from 0 S to 1.0 percent based on total weight of melamine and continuous phase including polymer solids. Suitable dispersing aids include derivatives of Fatty acids ana particularly amine salts of electroneutral fatty acids. Exemplary of a commercially available and preferred dispersing aid suitable for use in this present invention is TEGO~ISPERS"' 705 avail-20 able from Th. Goldschmidt AG and understood to be an amine salt of a fatty acid.
The stable dispersion described hereinabove can be prepared by contacting andmixing the desired quantity of continuous phase, melamine and IPS and optior:al dispersing aid. The IK and optional dispersing aid may be present in the continuous phase prior to the addition of the melamine, added during the addition of melamine or subsequent to the addi-25 tion of the melamine For flexibility in the preparation of stable dispersions containing variousamounts of melamine, advantageously the continuous phase, IPS and optional dispersing a id are premixed and then in a subseguent step mixed with the melamine. To Facilitate the mixing of the components when preparing the stable dispersion it is desirable to conduct the proce-dure at an elevated temperature. The elevated temperature need not be greater than 60C
30 and preferably is from 3ûC to 60C, more preferably from 40C to 55~C. Depencling on thebatch size of the preparation, components and their amounts, and mixing conditions em-ployed, mixing times may vary from ~en to five hours.
This invention also relates to a polyurethane polymer obtained by contacting andintimately mixing under reaction conditions an organic isocyanate with an isocyanate-reactive 35 composition that comprises the described stable dispersion. The isocyanate-reactive composi-tion comprises the dispersion in a quantity sufficient to provide for an end melamine concen-tration within the polymer that provides for the desired modification of the combustion char-acteristics of the polymer. for this purpose, typically the melamine/polymer polyol 2 1 1 ~ r~ 7 ~
WO 93/07193 PCr/VS92/û83~, dispersion will comprise at least 25, preferably at least 35, and more preferably at least 45 percent by weightof the total isocyanate-reactive composition including dispersion present. In addition to the dispersion, the isocyanate-reactive composition may also contain other isocyanate-reactive compounds especially other polyols, including polyether polyols, polyester 5 polyols, chain-extending agents, and same or different polymer polyols optionally characterized bythe absence of melamine dispersed therein. Suitable additional isocyanate-reactive compoundsthat may be present include polyether polyols having an average functionality of from 1.6, preferably from 1.8, more preferably from 1.9, up to 3.0; an average hydroxyl equivalent weight of from 500 to 5000, preferably from 1000 to 3000, and more 10 preferably from 1500 to 2500; and optionally a primary hydroxyl content of at least 30 and preferably at least 50 percent of its total hydroxyl content. By "average functional ity~ it is understood the average number of isocyanate-reactive hydrogen atomslmolecule. Exemplary of suitable commercially available polyether po!yols for use this invention are those polyether polyol produns designated by the trademark "VORANOl." and include VORANOL CP 4B00 and 15 VORANOL CP-6001 available from The Dow Chemical Company.
The organic polyisocyanates useful in preparing the polyurethane polymer include thcsse containing at least 2 and preferably from 2.0 to 3.0 isocyanate groups per molecule. Suitable isocyanates include aromatic polyisocyanates, aliphatic, cycioaliphatic and heterocyclic poiyisocyanates used alone or in admixture. The preferred isocyanates used in the 20 practice of this invention are aromatic polyisocyariates and include toluene diisocyanate, especially mixturesof the 2,4 and 2,6 isomers in weight ratios of 65:35 or 80:20; and polyisocyanate mixtures comprising 2,4'- or 4,4'-methylene diphenylisocyanate; or isocyanate--terminated prepolymers thereof.
When preparing a polyurethane polymer according to the present invention, the 25 isocyanate is present in an amount to provide from 0.85 to t.25, preferably at least 0.95, more preferably at least 1.0 and most preferably at least 1.02, and preferably at most 1.15, and more preferably at most 1.05 isocyanate groups per isocyanate reactive hydrogen atom present including those of any water present.
To obtain polyurethane polymer having a reduced density it is necessary to 30 prepare the polymer in the presence of a blowing agent. Advantageously, the blowing agent is presentinanamounttoprovidelheresultingpolymerwithanoveralldensityoffrom 10to 100, preferably from 15 to 80, and more preferably from 20 tO 60 kglm3. A preferred blowing agent for general use in the production of the polymer of this invention iswateradvantageously present in proportions of from û.5 to 8, preferably from 1 to 6, and more 35 preferably from 2 to 6 percent based on the total weight of the isocyanate-reactive composition. Non-reactive blowing agents can be used in conjunction with water or less preferably as a total replacement of water. These include substances which are vapori~ed at the temperatures produced by the exotherm of the isocyanatelreactive hydrogen reanion. The 38,7.80~
2 1~ 3 .
variousblowing agents are well known in the art and include certain halogen- and non-halogen-substituted aliphatic or cycloaliphatic hydrocarbons having boiling points ran~ing from -40C to + 100C including methylene chloride, volatile fluorocarbons and chlorofluoro-carbons, e.g. trichlorofluoromethane, dichlorodifluoromethane and 1-chloro-2-fluoroethane 5 and !ow boiling hydrocarbons, e.g. n-propane, cyclopropane, butane, isobutane, pentane, hex-ane, cyclohexane and their mixtures.
Advantageously, to promote the formation of urea and/or urethane linkages of the polymer, advantageously catalysts are present. Suitable catalysts are those known to those skilled in the art of preparing polyurethane polymers and include tertiary amines and metallic 10 compounds. Useful tertiary amines include N-alkylmorpholines, such as N-ethylmorpholine, N,N-dialkylcyclohexylamines where the alkyl groups are methyl, ethyl, propyl and butyl, trialky-lamines such as triethylamine, tri propylamine, tributylamine and triamylamine, triethylenedia-mine, bis~2-dimethylaminoethyl~ ether, N,N-dimethylaminoethyl--N',N'-dimethylaminopropyl ether, and othertertiary amineswell known in the art. Useful 15 metal compounds include those of bismuth, lead, titanium, iron, antimony, uranium, cadmium, cobalt, aluminum, mercury, zinc, nickel, cerium, vanadium, copper, manganese, zirconium and tin. Tin compounds are particularly useful, examples including stannous octoate, (stannous-2-ethylhexoate) and dibutyltin dilaurate The levels of catalyst used are conventional, typically ranging from 0.01 to 3 parts by weight per 100 parts of isocyanate-reactive composition.
To promote the formation of foam of desirable quality and cell structure ad~anta-g~ously at least one surfactant and/or cell reguiating agent is present when preparing the poly-urethane. Suitable surfactants include non-silicone containing surfactants, such as poly(alkyleneoxides) and the diverse silicone surfactants, preferably those which are block co-polyrners of a polysiloxane and a polyoxyalkylene as described in U.S. Patent 3,629,308. Exem-25 plary of such surfactants are the products designated as DC-193 and Q4-3667 available from Dow Corning and TEGOSTAB'~ B4113 and ~868~ available from Th. GoldschmidtAG. Theamount of surfactants advantageously employed is from 0.1 to 3, preferably from 0.2 to 1 .S
percent by total weight of the isocyanate-reactive composition.
In addition to the above-mentioned components, other components or additives 30 which advantageously may be present when preparing polyurethane foam include fillers; pig-ments; antistatic agents and flame re-tardants, for example, tris~chloroethyl)phosphonate (TCEP) and dimethoxymethyl phosphonate ~DMMP).
The polymers according to this invention can be prepared by any of the methods known in the art, including prepolymer and quasi-prepolymer methods though preferred are 35 one-shot procedures. Typical of a suitable manufacturing procedure is that as disclosed in U S.
Pat~nt 3,874,988. Other suitable manufacturin~ procedures are such as described in, for exam-ple, "Polyurethanes Handbook" by Gun-ter Oertel Hanser Publishes Munich ISBN 0-02-948920-2 (1985).
9 ;~
In a second aspect, this invention is a process for preparing a stable dispersion as described in the first aspect.
In a third aspect, this invention is a polyurethane polymer obtainable by contact-ing under reaction conditions an organic isocyanate with an isocyanate reactive composition 5 which contains a stable dispersion as claimed in Claim 1 wherein the organic polyisocyanate is present in an amount to provide from 0.85 to about 1.25 isocyanate groups per isocyanate reac-tive hydrogen atom present characterized in that the polymer has dispersed, based on total weight of polymer, therein: from 2 to 30 percent of melamine that has a mean particle size of from at least 25 and up to 125 micrometers; from 0.1 to 2.5 percent of an inorganic particulate 10 solid being a silicate, a silicic acid or a fumed silicic acid which has an average particle size of from S to 30 nanometers; and from 2 to 25 percent of an organic polymer solid.
Surprisingly, such above-described melamine polymer polyol dispersions are sta-ble. Additionally, such stabilized dispersions can be conveniently processed to provide flexible polyurethane foam exhibiting desirable combustion-modified characteristics and overall com-15 mercially attractive physical properties.
The stable dispersion of this invention has a continuous phase comprising a polyolhaving suspended therein an organic polymer solid and having further dispersed therei n m~-lamine particles and an inorganic particulate solid (sometimes referred to hereinafter as IPS).
By "stable" it is understood that when the dispersion is stored at room temperature, without 20 agitation, the melamine essentially remains dispersed in the continuous phase with little or no sedimentation being observed. If sedimentation should occur the dispersion of this invention may be characterized in that only a minimum of effort is required to redisperse the melamine due to the presence of the IPS. Generally little or no melamine sedimentation will occur within the first 2 weeks after preparation of the dispersion. Depending on the amount of IPS present, 25 frequently little or no melamine sedimentation may occur in the first 12 or even first 20 weeks after preparation of the dispersion.
The continuous phase of the stable dispersion comprises a polyether polyol or mixture of polyether polyols containing from 4 to S0 weight percent of a polymer solid. Prefer-ably such polyol contains the polymer solid in an amount of from 4 to 30, more preferably from 30 5 to 2~ percent. Polyol containing a higher solids content than this will generally be highly vis-cous and difficult to manage; a lower solids content normally will not provide for any notice-able effect when incorporated into a polyurethane polymer. A polyether polyol containing such solid is generally referred to as a "polymer polyol". To provide for a continuous phase having such a polymer solids content as mentioned hereinabove, advantageously the continu-35 ous phase comprises such a polymer polyol in an amount of at least S0, pre-ferably at least 60, and more preferably at least 75 weight percent of the continuous phase. When the continuous phase is not constituted in its entirety by the polymer polyol the remaining percentage may be constituted by other conventional polyoxyalkylene polyols used S~ g~ f 3S,7~0-F
- 211~ ~7~3 in the p!eparation of polyurethane polymers. Suitable polyols containing an organic polymer solid for use in this present invention include SAN-, PHD- and PlPA-type polymer polyols. Pro-cesses for obtaining suitable PHD- and PlPA-type polymer polyols are disclosed in U.S. Patents 4,374,209; 3,325,421; 4,042,537 and 4,093,567. Processes for obtaining suitable SAN copolymer polyols for use in this present inYention are described in U.S. Patents 3,385,351; 3,304,273;
3,523,093 and 3,110,695.
When using the stable dispersion for the preparation of flexible polyurethane foams it is advantageous if the polyol of the continuous phase has an average of from 2 to 4 isocyanate-reactive groups per molecule; an average hydroxyl equivalent weight of from 750 .~ 3000, preferably at least 1000, more preferably at least 1200; and preferably ~t most 2500, more preferably at most 2000. Additionally it is advantageous for the polyol to have a primary hydroxyl content of from at least 10, preferably ~rom at least 30, and more preferably from at least 50 percent of its total hydroxyl content. Use of a polyol having such characteristics gener-ally provides for a flexible polyurethane foam with desirable physical properties. In a preferred 15 embodiment of this invention the continuous phase comprises a SAN polymer polyol, and more p-eferably consists essentially of a SAN polymer polyol. Exemplary of sui table commercially available SAN polymer polyols include those sold by The Dow Chemical Company and include the products designated as VORANOL ~ CP-8020, VORANOL ~ CP-8010, VORANOL'~ CP-8030, and products designated as VORALUX'~ in conjunction with the designation codes HN200 20 through ~o HN206.
The melamine dispersed within the continuous phase is characterized ir that it has an average particle size of frorn 25 to 125 micrometers. The melamine particle size is pref-erably at least 40 and more preferably at least 50 micrometers, and preferably at most 100, more preferably at most 90 micrometers. Melamine having such a particle size is readily avail-25 able commercially and may be obtained and used directly without the need for particle size re-duction through milling, grinding or such like techniques. Use of melamine having a smaller particle size than defined provides mixtures whose viscosity is undesirably high for convenient processing and preparation of polyurethane foam. Use of melamine having an average parti-cle size significantly greater than d~fi ned above is not desirable as when present i n a foami ng 30 process poor quality or collapsed foam may resu!t. The stable dispersion of the present inven-tion comprises the melamine in an amount sufficient to provide for the desired combusti~n modification of flexible polyurethane foams prepared therefrom. The dispersion comprises the melamine in an amount of from 20 to 60, preferably at least 25, and more preferably at least 30, and preferably at most 55, more preferably at most 50, and most preferably at most 35 35 weight per~ent based on total weight of melamine and polyol including polymer solids. When the melamine has a small particle size generally it will be present in a smaller amount than when having a larger particle size.
: 8,~8~
r) o The stability of the melamine dispersed in the continuous phase is provided for by the presence of an inorganic particulate solid (IPS) that has an average particle si~e of from 5 to 30 nanometers. Preferably, the IPS has an average particle size of from S to 20, and more pref-erably from ~ to 14 nanometers. The IPS is present in an amount of from 0.2 to 5, preferably at S least 0.25, more preferably at least 0.5, and preferably at most 3.0, more preferably at most 2.0 percent based on the total weight of rr~elamine and polyol including polymer solids present.
Greater amounts of the IPS generally providing for enhanced storage stability characteristics of the dispersion and ability to redisperse the melamine should any sedimentation occur. Suitable IPS substances for use in the present invention include hydrophilic substances compatible with 10 processes for the preparation of polyurethane polymers such as silicates or especially silicic acids and particularly fumed silicic acids. Exemplary of preferred silicic acid products for use in this present in~ention include substances designated as A~ROSIL'~ 200, Af ROSlL'~ 300 and AERO-SIL'~ 380 available from Degussa GmbH, Germany.
Optionally when preparing the dispersions of this invention a dispersing aid may15 be present. When present, the dispersinS~ aid advantageously is used in an amount of from 0.25 to 1.5, preferably from 0 S to 1.0 percent based on total weight of melamine and continuous phase including polymer solids. Suitable dispersing aids include derivatives of Fatty acids ana particularly amine salts of electroneutral fatty acids. Exemplary of a commercially available and preferred dispersing aid suitable for use in this present invention is TEGO~ISPERS"' 705 avail-20 able from Th. Goldschmidt AG and understood to be an amine salt of a fatty acid.
The stable dispersion described hereinabove can be prepared by contacting andmixing the desired quantity of continuous phase, melamine and IPS and optior:al dispersing aid. The IK and optional dispersing aid may be present in the continuous phase prior to the addition of the melamine, added during the addition of melamine or subsequent to the addi-25 tion of the melamine For flexibility in the preparation of stable dispersions containing variousamounts of melamine, advantageously the continuous phase, IPS and optional dispersing a id are premixed and then in a subseguent step mixed with the melamine. To Facilitate the mixing of the components when preparing the stable dispersion it is desirable to conduct the proce-dure at an elevated temperature. The elevated temperature need not be greater than 60C
30 and preferably is from 3ûC to 60C, more preferably from 40C to 55~C. Depencling on thebatch size of the preparation, components and their amounts, and mixing conditions em-ployed, mixing times may vary from ~en to five hours.
This invention also relates to a polyurethane polymer obtained by contacting andintimately mixing under reaction conditions an organic isocyanate with an isocyanate-reactive 35 composition that comprises the described stable dispersion. The isocyanate-reactive composi-tion comprises the dispersion in a quantity sufficient to provide for an end melamine concen-tration within the polymer that provides for the desired modification of the combustion char-acteristics of the polymer. for this purpose, typically the melamine/polymer polyol 2 1 1 ~ r~ 7 ~
WO 93/07193 PCr/VS92/û83~, dispersion will comprise at least 25, preferably at least 35, and more preferably at least 45 percent by weightof the total isocyanate-reactive composition including dispersion present. In addition to the dispersion, the isocyanate-reactive composition may also contain other isocyanate-reactive compounds especially other polyols, including polyether polyols, polyester 5 polyols, chain-extending agents, and same or different polymer polyols optionally characterized bythe absence of melamine dispersed therein. Suitable additional isocyanate-reactive compoundsthat may be present include polyether polyols having an average functionality of from 1.6, preferably from 1.8, more preferably from 1.9, up to 3.0; an average hydroxyl equivalent weight of from 500 to 5000, preferably from 1000 to 3000, and more 10 preferably from 1500 to 2500; and optionally a primary hydroxyl content of at least 30 and preferably at least 50 percent of its total hydroxyl content. By "average functional ity~ it is understood the average number of isocyanate-reactive hydrogen atomslmolecule. Exemplary of suitable commercially available polyether po!yols for use this invention are those polyether polyol produns designated by the trademark "VORANOl." and include VORANOL CP 4B00 and 15 VORANOL CP-6001 available from The Dow Chemical Company.
The organic polyisocyanates useful in preparing the polyurethane polymer include thcsse containing at least 2 and preferably from 2.0 to 3.0 isocyanate groups per molecule. Suitable isocyanates include aromatic polyisocyanates, aliphatic, cycioaliphatic and heterocyclic poiyisocyanates used alone or in admixture. The preferred isocyanates used in the 20 practice of this invention are aromatic polyisocyariates and include toluene diisocyanate, especially mixturesof the 2,4 and 2,6 isomers in weight ratios of 65:35 or 80:20; and polyisocyanate mixtures comprising 2,4'- or 4,4'-methylene diphenylisocyanate; or isocyanate--terminated prepolymers thereof.
When preparing a polyurethane polymer according to the present invention, the 25 isocyanate is present in an amount to provide from 0.85 to t.25, preferably at least 0.95, more preferably at least 1.0 and most preferably at least 1.02, and preferably at most 1.15, and more preferably at most 1.05 isocyanate groups per isocyanate reactive hydrogen atom present including those of any water present.
To obtain polyurethane polymer having a reduced density it is necessary to 30 prepare the polymer in the presence of a blowing agent. Advantageously, the blowing agent is presentinanamounttoprovidelheresultingpolymerwithanoveralldensityoffrom 10to 100, preferably from 15 to 80, and more preferably from 20 tO 60 kglm3. A preferred blowing agent for general use in the production of the polymer of this invention iswateradvantageously present in proportions of from û.5 to 8, preferably from 1 to 6, and more 35 preferably from 2 to 6 percent based on the total weight of the isocyanate-reactive composition. Non-reactive blowing agents can be used in conjunction with water or less preferably as a total replacement of water. These include substances which are vapori~ed at the temperatures produced by the exotherm of the isocyanatelreactive hydrogen reanion. The 38,7.80~
2 1~ 3 .
variousblowing agents are well known in the art and include certain halogen- and non-halogen-substituted aliphatic or cycloaliphatic hydrocarbons having boiling points ran~ing from -40C to + 100C including methylene chloride, volatile fluorocarbons and chlorofluoro-carbons, e.g. trichlorofluoromethane, dichlorodifluoromethane and 1-chloro-2-fluoroethane 5 and !ow boiling hydrocarbons, e.g. n-propane, cyclopropane, butane, isobutane, pentane, hex-ane, cyclohexane and their mixtures.
Advantageously, to promote the formation of urea and/or urethane linkages of the polymer, advantageously catalysts are present. Suitable catalysts are those known to those skilled in the art of preparing polyurethane polymers and include tertiary amines and metallic 10 compounds. Useful tertiary amines include N-alkylmorpholines, such as N-ethylmorpholine, N,N-dialkylcyclohexylamines where the alkyl groups are methyl, ethyl, propyl and butyl, trialky-lamines such as triethylamine, tri propylamine, tributylamine and triamylamine, triethylenedia-mine, bis~2-dimethylaminoethyl~ ether, N,N-dimethylaminoethyl--N',N'-dimethylaminopropyl ether, and othertertiary amineswell known in the art. Useful 15 metal compounds include those of bismuth, lead, titanium, iron, antimony, uranium, cadmium, cobalt, aluminum, mercury, zinc, nickel, cerium, vanadium, copper, manganese, zirconium and tin. Tin compounds are particularly useful, examples including stannous octoate, (stannous-2-ethylhexoate) and dibutyltin dilaurate The levels of catalyst used are conventional, typically ranging from 0.01 to 3 parts by weight per 100 parts of isocyanate-reactive composition.
To promote the formation of foam of desirable quality and cell structure ad~anta-g~ously at least one surfactant and/or cell reguiating agent is present when preparing the poly-urethane. Suitable surfactants include non-silicone containing surfactants, such as poly(alkyleneoxides) and the diverse silicone surfactants, preferably those which are block co-polyrners of a polysiloxane and a polyoxyalkylene as described in U.S. Patent 3,629,308. Exem-25 plary of such surfactants are the products designated as DC-193 and Q4-3667 available from Dow Corning and TEGOSTAB'~ B4113 and ~868~ available from Th. GoldschmidtAG. Theamount of surfactants advantageously employed is from 0.1 to 3, preferably from 0.2 to 1 .S
percent by total weight of the isocyanate-reactive composition.
In addition to the above-mentioned components, other components or additives 30 which advantageously may be present when preparing polyurethane foam include fillers; pig-ments; antistatic agents and flame re-tardants, for example, tris~chloroethyl)phosphonate (TCEP) and dimethoxymethyl phosphonate ~DMMP).
The polymers according to this invention can be prepared by any of the methods known in the art, including prepolymer and quasi-prepolymer methods though preferred are 35 one-shot procedures. Typical of a suitable manufacturing procedure is that as disclosed in U S.
Pat~nt 3,874,988. Other suitable manufacturin~ procedures are such as described in, for exam-ple, "Polyurethanes Handbook" by Gun-ter Oertel Hanser Publishes Munich ISBN 0-02-948920-2 (1985).
. $~~r ~r ~ .
The Qolyurethane polymer obtained according to this invention comprises the melamine in an amount sufficient to provide the polymer with the desired modification of the combustion characteristics of the polymer~ Typically the polyurethane polymer contains me-lamine particles from 2 to 30 and more typically ~rom 5 to 25 percent of total polymer weight S including melamine. These percentages are lower than those of the melamine content of the stable dispersion due to dilution by other reactive components such as the po!yisocyanate em-ployed to prepare the polyurethane polymer. Accordingly the polyurethane polymer will also contain the organic polymer solid and IPS in corrffpondingly lower amounts. The IPS typically being present in an amount of from 0.1 to 2.5, more typically from 0.2 to 1.5 percent of total 10 polymer weight including melami-ne present. The organic polymer solid typically being present in an amount of from 2 to 25, and more typically from 2 to 15 percent of total polymer weight.
The polyurethane polymers, particularly foams, prepared from the dispersion of this invention are useful in the pre3aration of articles such as upholstery materials, packing ma-terials and insulation for sound or :-eat, and automotive applications such as, for example, 15 head rests and steering wheels.
In the following exa- 1ples, all amounts are given as parts by weight. The exam-ples according to the invention are :llustrative, but not limitative. The materials used in the~x amples are identified as follows:
20 Melamine A melamine, ave 3ge particle size 90 micrometers, supplied by DSM;
Melamine B melamine, ave ,ge particle size 10 micrometers, supplied by DSM;
Continuous phase Polyol A SAN copolyme - polyol (10% solids), VORANOL ~ CP-8020 supplied by The DowChemica ~ompany;
2; Polyol 8 SAN copolymer polyol (15% solids), VORALUX ~ HN 202 supplied by The Dow Chemical Company;
Inorganic Fumed silicic a.id, AEROSIL ~ 200, supplied by Degussa; with an particulate solid average particle si~e of 12 nanometers;
(IPS) 30 DispersingAid TEGODlSPER~705suppliedbyTh.GoldschmidtAG~;
THERMO~IN ~ 101 a halogen/phosphorus flame retardant additivesupplied by Olin S.A.r Catalyst a combination of DABCO ~ 33LV supplied by Air Products; NIAX~ A-1 sup-plied by Union Carbide Corporation; and dibutyltin dilaurate, weight ratio 28: 12:60 respectively;
35 Surfanant TEGOSTAB ~ B8681 supplied by Th; Goldschmidt AG.;
TDI-80 Toluene diisocyanate (2,4-/2,6- -isomer ratio 80:20).
~2~ls~7a WO 93/07193 PCl /US92tO836 Reported properties of foams as obtained are determined according to the following procedures; tensile strength and elongation - DiN 53571; compression load deflection (CLD)- DIN 53577; and for indentation load deflection (ILD)- DIN 53576. Flame retardant, hereinafter F.R., performance of foam is observed according to Crib 5 as specified in 5 BS 5852, part 2. The reported flame retardancy performance is representative of that to be obtained with such foam but should not be considered as reflecting the performance under actual fire conditions.
ExamDle 1 The following dispersions are prepared with components as indicated in Table 1.
Melamine is added to the continuous phase, the polyol, in the presence of the inorganic particulate solid and optional dispersing aid as indicated. The mixture is mechanically stirred until a temperature of 50C is reached and then allowed to cool to 25C before measuring the viscosity. Stability of the resulting dispersion is monitored by observing the time elapsed until 15 the first visual observation of sedimentation is noted. Longer time periods being considered indicative of better storage stability characteristics.
From the data presented in Table 1 it is determined that the presence of the IPSprovides for the stability of the dispersion. Comparison of Dispersion 6 with Dispersion 1 indicates that the observation of enhanced stability is not merely an artifact of increasing 20 viscosity of the sygem.
2~19S7 3 `
WO 93/07193 PCl/US92/0~s36 C ~ _ o o o o _ o U o ~C
_ 'c~ o _ o o _ _ o~ o~v _ _ i:~ o _ _ o o o o ~J A 3 c~ ~ o _ _ o o _ r~ ~0 A
Q o o ~ -.~ _ 0 0 _ O _ U~ ~ ~ 3 _ . . _ l -I ~Q~ ~ - ~ ~ ~
Q~ ~ - ~ ~ - O~ ~
c~ u~ o _ o _ o o ~ o A 3 ~ ~ o _ o _ o o o ", A 3 v.
'c~ o _ oO _ o. _ - ~o ~o ~ .~ .
_ _ ~ ~
2 ~, o _ o _ _ _ o "1 A 3 .c n o _ o _ -o _ o ~ ~ _._ _ _ .
o o ~1: C 'O .~ >~ ~ X
3 o `J s E ~ .~ ~o E --o c O ~, ~11 9 ~ I ~
WO 93/071~ PCT/USg2/08 Example 2 A stable dispersion of melamine in a PHD polymer polyol is prepared, which in the absence of an inorganic particulate solid is also observed not to possess desirable stability 5 characteristics. A similar lack of dispersion stability is also observed for melamine dispersed in a PIPA polymer polyol when an IPS is absent.
Table ?
Dispersion Dispersion Dispersion parts by weight 1 1 C~ D~
_ PHD-polymer 100 100 polyol O
_ . _.
PlPA-polymer / / 100 polyol (~ _ .
Melamine A 100 100 100 . 1.5-_ .
Dispersing aid / / /
.
Initial viscosity 53680 9720 17300 (mPasl2 1 C) Stability > 12 wks 0 wks 0 wks ~ Desmophen 7652, supplied by Bayer * Not an example of thi~ invention-It can also be seen from this example that use of a PHD polymer polyol provides dispersions which have an undesirably higher viscosity than like dispersions prepared from a SAN polymer polyol of comparable solids content, see Example 1, Dispersion 2 and Dispersion A.
. 35 . 2 ~ 7 a WO 93/07193 PCl/US92/0836-ExamPle 3 Polyurethane foam is prepared from Dispersions 4 and 10. The formulation used to prepare the foam and the physical properties of the resulting faarn is given in Table 3.
5 Comparative foam A is prepared from similar components but wherein the melamine is mixed directly in the isocyanate-reactive composition and used immediately in the preparation of a polyurethane foam. Processing and physical properties of the resulting foams are seen to be essentially equivalent with the exception of results form the F.R. testing. Comparative foam A
is observed to have a significantly inferior F.R. performance compared to Foam 1 A further 1O advantage observed when preparing polyurethane foam with the stable dispersion of this invention by a continuous foaming process is the enhanced reproducibility/consistency of the F.R. performance of the foam. During the continuous preparation of foam, the concentration of melamine in the foam can vary depending on whether the foam sample considered is produced at an early or late stage o~f the continuous foaming process. The variance in 15 melamineconcentrationcanbeobservedthroughpoorreproducibilityoftheF.R.performance observed for different samples of the foam. Non or poor stability of the dispersed melamine is considered to result in a non uniform distribution of melamine.
.
7 a WO 93/07193 PC'r/US92/0836, Table 3 .
Comparative S pans by weight Foam 1 Foam 2 Foam A*
Dispersion 4 60.3 /
Dispersion 10 / 60.2 Polyol A 70 70 100 o Melamine A / / 30 Diethanolamine 1.25 1.25 1 .10 Surfactant _0.6 0.6 0.6 Catalyst 0.42 0.42 0.42 . Thermolin 101 5.0 5.0 5.0 W~r ~3 5 3.5 3.5 Index 105 wtA~ melamine 20 20 20 in PU polymer .
20 (kglm3) 32.4 31:5 28.1 ..
Elongation (%) 145 115 139 Tensile Strength81 77 84 F.R. 49 33 > 60 . 2s performance, weight loss _ *Not an example of the invention 3s
The Qolyurethane polymer obtained according to this invention comprises the melamine in an amount sufficient to provide the polymer with the desired modification of the combustion characteristics of the polymer~ Typically the polyurethane polymer contains me-lamine particles from 2 to 30 and more typically ~rom 5 to 25 percent of total polymer weight S including melamine. These percentages are lower than those of the melamine content of the stable dispersion due to dilution by other reactive components such as the po!yisocyanate em-ployed to prepare the polyurethane polymer. Accordingly the polyurethane polymer will also contain the organic polymer solid and IPS in corrffpondingly lower amounts. The IPS typically being present in an amount of from 0.1 to 2.5, more typically from 0.2 to 1.5 percent of total 10 polymer weight including melami-ne present. The organic polymer solid typically being present in an amount of from 2 to 25, and more typically from 2 to 15 percent of total polymer weight.
The polyurethane polymers, particularly foams, prepared from the dispersion of this invention are useful in the pre3aration of articles such as upholstery materials, packing ma-terials and insulation for sound or :-eat, and automotive applications such as, for example, 15 head rests and steering wheels.
In the following exa- 1ples, all amounts are given as parts by weight. The exam-ples according to the invention are :llustrative, but not limitative. The materials used in the~x amples are identified as follows:
20 Melamine A melamine, ave 3ge particle size 90 micrometers, supplied by DSM;
Melamine B melamine, ave ,ge particle size 10 micrometers, supplied by DSM;
Continuous phase Polyol A SAN copolyme - polyol (10% solids), VORANOL ~ CP-8020 supplied by The DowChemica ~ompany;
2; Polyol 8 SAN copolymer polyol (15% solids), VORALUX ~ HN 202 supplied by The Dow Chemical Company;
Inorganic Fumed silicic a.id, AEROSIL ~ 200, supplied by Degussa; with an particulate solid average particle si~e of 12 nanometers;
(IPS) 30 DispersingAid TEGODlSPER~705suppliedbyTh.GoldschmidtAG~;
THERMO~IN ~ 101 a halogen/phosphorus flame retardant additivesupplied by Olin S.A.r Catalyst a combination of DABCO ~ 33LV supplied by Air Products; NIAX~ A-1 sup-plied by Union Carbide Corporation; and dibutyltin dilaurate, weight ratio 28: 12:60 respectively;
35 Surfanant TEGOSTAB ~ B8681 supplied by Th; Goldschmidt AG.;
TDI-80 Toluene diisocyanate (2,4-/2,6- -isomer ratio 80:20).
~2~ls~7a WO 93/07193 PCl /US92tO836 Reported properties of foams as obtained are determined according to the following procedures; tensile strength and elongation - DiN 53571; compression load deflection (CLD)- DIN 53577; and for indentation load deflection (ILD)- DIN 53576. Flame retardant, hereinafter F.R., performance of foam is observed according to Crib 5 as specified in 5 BS 5852, part 2. The reported flame retardancy performance is representative of that to be obtained with such foam but should not be considered as reflecting the performance under actual fire conditions.
ExamDle 1 The following dispersions are prepared with components as indicated in Table 1.
Melamine is added to the continuous phase, the polyol, in the presence of the inorganic particulate solid and optional dispersing aid as indicated. The mixture is mechanically stirred until a temperature of 50C is reached and then allowed to cool to 25C before measuring the viscosity. Stability of the resulting dispersion is monitored by observing the time elapsed until 15 the first visual observation of sedimentation is noted. Longer time periods being considered indicative of better storage stability characteristics.
From the data presented in Table 1 it is determined that the presence of the IPSprovides for the stability of the dispersion. Comparison of Dispersion 6 with Dispersion 1 indicates that the observation of enhanced stability is not merely an artifact of increasing 20 viscosity of the sygem.
2~19S7 3 `
WO 93/07193 PCl/US92/0~s36 C ~ _ o o o o _ o U o ~C
_ 'c~ o _ o o _ _ o~ o~v _ _ i:~ o _ _ o o o o ~J A 3 c~ ~ o _ _ o o _ r~ ~0 A
Q o o ~ -.~ _ 0 0 _ O _ U~ ~ ~ 3 _ . . _ l -I ~Q~ ~ - ~ ~ ~
Q~ ~ - ~ ~ - O~ ~
c~ u~ o _ o _ o o ~ o A 3 ~ ~ o _ o _ o o o ", A 3 v.
'c~ o _ oO _ o. _ - ~o ~o ~ .~ .
_ _ ~ ~
2 ~, o _ o _ _ _ o "1 A 3 .c n o _ o _ -o _ o ~ ~ _._ _ _ .
o o ~1: C 'O .~ >~ ~ X
3 o `J s E ~ .~ ~o E --o c O ~, ~11 9 ~ I ~
WO 93/071~ PCT/USg2/08 Example 2 A stable dispersion of melamine in a PHD polymer polyol is prepared, which in the absence of an inorganic particulate solid is also observed not to possess desirable stability 5 characteristics. A similar lack of dispersion stability is also observed for melamine dispersed in a PIPA polymer polyol when an IPS is absent.
Table ?
Dispersion Dispersion Dispersion parts by weight 1 1 C~ D~
_ PHD-polymer 100 100 polyol O
_ . _.
PlPA-polymer / / 100 polyol (~ _ .
Melamine A 100 100 100 . 1.5-_ .
Dispersing aid / / /
.
Initial viscosity 53680 9720 17300 (mPasl2 1 C) Stability > 12 wks 0 wks 0 wks ~ Desmophen 7652, supplied by Bayer * Not an example of thi~ invention-It can also be seen from this example that use of a PHD polymer polyol provides dispersions which have an undesirably higher viscosity than like dispersions prepared from a SAN polymer polyol of comparable solids content, see Example 1, Dispersion 2 and Dispersion A.
. 35 . 2 ~ 7 a WO 93/07193 PCl/US92/0836-ExamPle 3 Polyurethane foam is prepared from Dispersions 4 and 10. The formulation used to prepare the foam and the physical properties of the resulting faarn is given in Table 3.
5 Comparative foam A is prepared from similar components but wherein the melamine is mixed directly in the isocyanate-reactive composition and used immediately in the preparation of a polyurethane foam. Processing and physical properties of the resulting foams are seen to be essentially equivalent with the exception of results form the F.R. testing. Comparative foam A
is observed to have a significantly inferior F.R. performance compared to Foam 1 A further 1O advantage observed when preparing polyurethane foam with the stable dispersion of this invention by a continuous foaming process is the enhanced reproducibility/consistency of the F.R. performance of the foam. During the continuous preparation of foam, the concentration of melamine in the foam can vary depending on whether the foam sample considered is produced at an early or late stage o~f the continuous foaming process. The variance in 15 melamineconcentrationcanbeobservedthroughpoorreproducibilityoftheF.R.performance observed for different samples of the foam. Non or poor stability of the dispersed melamine is considered to result in a non uniform distribution of melamine.
.
7 a WO 93/07193 PC'r/US92/0836, Table 3 .
Comparative S pans by weight Foam 1 Foam 2 Foam A*
Dispersion 4 60.3 /
Dispersion 10 / 60.2 Polyol A 70 70 100 o Melamine A / / 30 Diethanolamine 1.25 1.25 1 .10 Surfactant _0.6 0.6 0.6 Catalyst 0.42 0.42 0.42 . Thermolin 101 5.0 5.0 5.0 W~r ~3 5 3.5 3.5 Index 105 wtA~ melamine 20 20 20 in PU polymer .
20 (kglm3) 32.4 31:5 28.1 ..
Elongation (%) 145 115 139 Tensile Strength81 77 84 F.R. 49 33 > 60 . 2s performance, weight loss _ *Not an example of the invention 3s
Claims (10)
1 A stable melamine-polyether polyol dispersion in the presence of an inorganic particulate solid characterized in that:
(a) the polyol is a polymer-modified polyether polyol or mixture thereof which contains from 4 to 50 weight percent of an organic polymer solid;
(b) the melamine, present in from 20 to 60 percent based on total weight of (a) and (b), has a mean particle size of from at least 25 and up to 125 micrometers; and (c) the inorganic particulate solid, present in from 0.2 to 5 percent based on the total weight of (a) and (b), is a silicic acid or a fumed silicic acid which has an average particle size of from 5 to 30 nanometers.
(a) the polyol is a polymer-modified polyether polyol or mixture thereof which contains from 4 to 50 weight percent of an organic polymer solid;
(b) the melamine, present in from 20 to 60 percent based on total weight of (a) and (b), has a mean particle size of from at least 25 and up to 125 micrometers; and (c) the inorganic particulate solid, present in from 0.2 to 5 percent based on the total weight of (a) and (b), is a silicic acid or a fumed silicic acid which has an average particle size of from 5 to 30 nanometers.
2 A dispersion as claimed in Claim 1 wherein the organic polymer solid comprises a styrene:acrylonitrile (SAN-), a polyurea (PHD-), or polyisocyanate-polyamine (PIPA-) polymer.
3 A dispersion as claimed in Claim 1 wherein the melamine has an average particle size of from 25 to 100 micrometers.
4 CANCELLED.
5. A dispersion as claimed in any one of Claims 1 to 3 wherein the inorganic particulate solid is a fumed silicic acid that has an average particle size of from 5 to 20 nanometers.
6. A dispersion as claimed in any one of Claims 1 to 3 wherein the inorganic particulate solid is present in an amount of from 0.25 to 3.0 weight percent.
7. A dispersion as claimed in Claim 1 wherein:
(a) the organic polymer solid, present in 5 to 20 weight percent, is a SAN polymer;
(b) the melamine has a mean particle size of from 25 to 100 micrometers; and (c) the inorganic particulate solid, present in from 0.25 to 3.0 percent, based on the total weight of (a) and (b), is a fumed silicic acid that has an average particle size of from 5 to 20 na-nometers.
(a) the organic polymer solid, present in 5 to 20 weight percent, is a SAN polymer;
(b) the melamine has a mean particle size of from 25 to 100 micrometers; and (c) the inorganic particulate solid, present in from 0.25 to 3.0 percent, based on the total weight of (a) and (b), is a fumed silicic acid that has an average particle size of from 5 to 20 na-nometers.
8. A dispersion as claimed in any one of the preceding claims further comprising a dispersing aid.
9. A process for preparing a stable dispersion which comprises contacting:
(a) a polymer-modified polyether polyol or mixture thereof containing from 4 to 50 weight percent of an organic polymer solid;
(b) melamine having a mean particle size of from at least 25 and up to 125 micrometers; and (c) an inorganic particulate solid which has an average particle size of from 5 to 30 nanometers and being a silicate, a silicic acid or a fumed silicic acid, characterized in that (b) is present in from 20 to 60 percent based on total weight of (a) and (b);
and in than (c) is present in from 0.2 to 5 percent based on total weight of (a) and (b).
(a) a polymer-modified polyether polyol or mixture thereof containing from 4 to 50 weight percent of an organic polymer solid;
(b) melamine having a mean particle size of from at least 25 and up to 125 micrometers; and (c) an inorganic particulate solid which has an average particle size of from 5 to 30 nanometers and being a silicate, a silicic acid or a fumed silicic acid, characterized in that (b) is present in from 20 to 60 percent based on total weight of (a) and (b);
and in than (c) is present in from 0.2 to 5 percent based on total weight of (a) and (b).
10. A polyurethane polymer obtainable by contacting under reaction condi-tions an organic isocyanate with an isocyanate reactive composition which contains a stable dis-persion as claimed in Claim 1 wherein the organic polyisocyanate is present in an amount to provide from 0.85 to about 1.25 isocyanate groups per isocyanate reactive hydrogen atom present characterized in that the polymer has dispersed, based on total weight of polymer, therein: from 2 to 30 percent of melamine that has an average particle size of from at least 25 and up to 125 micrometers; from 0.1 to 2.5 percent of an inorganic particulate solid being a sili-cate, a silicic acid or a fumed silicic acid which has an average particle size of from 5 to 30 na-nometers; and from 2 to 25 percent of an organic polymer solid.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US77347891A | 1991-10-09 | 1991-10-09 | |
| US07/773,478 | 1991-10-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2119570A1 true CA2119570A1 (en) | 1993-04-15 |
Family
ID=25098417
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002119570A Abandoned CA2119570A1 (en) | 1991-10-09 | 1992-09-30 | Stable melamine dispersions in polymer polyols and polyurethane foam therefrom |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0607312A1 (en) |
| CA (1) | CA2119570A1 (en) |
| WO (1) | WO1993007193A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19642246A1 (en) * | 1996-10-12 | 1998-04-16 | Basf Ag | Process for the preparation of a stable dispersion of melamine in polyol components |
| DE102005003299A1 (en) * | 2005-01-24 | 2006-07-27 | Goldschmidt Gmbh | Nanoparticles for the production of polyurethane foam |
| EP2565214A1 (en) * | 2011-09-02 | 2013-03-06 | Basf Se | Dispersion consisting of a liquid and a solid phase |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2932304A1 (en) * | 1979-08-09 | 1981-02-26 | Basf Ag | STABLE FILLER-POLYOL DISPERSIONS, A METHOD FOR THE PRODUCTION THEREOF AND THE USE FOR THE PRODUCTION OF POLYURETHANE PLASTICS, WHICH MAY BE FOAMED |
| GB8421967D0 (en) * | 1984-08-30 | 1984-10-03 | Hickory Springs Mfg Co | Polyurethane foams |
| GB2177405B (en) * | 1985-06-28 | 1989-08-23 | Basf Corp | Flame retardant polyurethane foams |
| US4644015A (en) * | 1986-05-08 | 1987-02-17 | Ashland Oil, Inc. | Stable polyol-melamine blend for use in the manufacture of fire retardant flexible urethane foam |
| GB8826727D0 (en) * | 1988-11-15 | 1988-12-21 | Bp Chem Int Ltd | Melamine/urea containing polymer polyols |
| AT394049B (en) * | 1989-04-04 | 1992-01-27 | Chemie Linz Gmbh | MELAMINE PREPARATION, STABLE DISPERSION OF MELAMINE IN POLYETHEROLS, METHOD FOR THE PRODUCTION AND THEIR USE |
| AT394565B (en) * | 1990-01-30 | 1992-05-11 | Chemie Linz Gmbh | MELAMINE PREPARATION CONTAINING CYANURIC ACID OR ITS DERIVATIVES AND STABLE DISPERSION OF MELAMINE IN POLYETHEROLS, METHOD FOR THE PRODUCTION THEREOF AND THEIR USE |
-
1992
- 1992-09-30 EP EP92921915A patent/EP0607312A1/en not_active Ceased
- 1992-09-30 CA CA002119570A patent/CA2119570A1/en not_active Abandoned
- 1992-09-30 WO PCT/US1992/008367 patent/WO1993007193A1/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| WO1993007193A1 (en) | 1993-04-15 |
| EP0607312A1 (en) | 1994-07-27 |
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