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
  • C08G18/08—Processes
  • C08G18/16—Catalysts
  • C08G18/18—Catalysts containing secondary or tertiary amines or salts thereof
  • C08G18/1825—Catalysts containing secondary or tertiary amines or salts thereof having hydroxy or primary amino groups
• • 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
  • C08G18/08—Processes
  • C08G18/16—Catalysts
  • C08G18/18—Catalysts containing secondary or tertiary amines or salts thereof
  • C08G18/1875—Catalysts containing secondary or tertiary amines or salts thereof containing ammonium salts or mixtures of secondary of tertiary amines and acids

Definitions

• This invention relates to the field of polyurethane chemistry. More specifically, the invention relates to a method of manufacturing a polyurethane foam using a catalyst as a co-polyol.
• Polyurethane foams may be rigid, semi-rigid, or flexible and have densities ranging from less than one pound to greater than fifty pounds"*per cubic foot. These foams have excellent strength, durability, light color, uniform cell size, and good heat-insulating properties and can be used in cushions, bedding, and fabric backing.
• Urethanes or polyurethanes can be formed by a reaction of di- or polyfunctional hydroxyl compounds, for example, hydroxyl-terminated polyesters or polyethers with di- or polyfunctional isocyanates.
• the repeating unit of a linear polyurethane derived from a dihydroxy compound, HOROH, and a diisocyanate, OCNR'NCO, can be represented by the general formula:
• the isocyanates disclosed in the several above-listed patents may be selected from a broad group of compounds, including toluene- 2,4-diisocyanate, 2,4-dimethyl-1,3-phenylene iisocyanate, 2,6- diisocyanate-benzofuran, and 2,4,6-toluenetri- isocyanate.
• Typical polyols may include pentaerythitol, ethoxylated trimeth lolpropane, or diethanolamine.
• Suitable surfactants include silicone glycol copolymers, and the blowing agent is often trifluorochloro ethane or dichloro- methane.
• Catalysts are selected from a group including quaternary ammonium bases, alkali metal salts, and organic quaternary ammonium salts.
• the methods of polyurethane foam ' manuf cture disclosed in the above patents all require that both a conventional polyol and a conventional catalyst be used, and the catalyst does not act as a polyol in the reaction.
• This invention comprises a novel method for the manufacture of a polyurethane foam, comprising blending the isocyanate with a polyol and a catalyst, the catalyst acting as a co-polyol in the reaction and being of the general formula:
• x is an integer between 1 and 10
• R4 is either -H
• R2, and R3 are selected from the group including
• aliphatic radical means alkyl and alkenyl groups having from 1 to 22 carbon atoms inclusive.
• alkyl groups are methyl, propyl, pentyl, octyl, decyl, tridecyl, octadecyl, and isomeric forms (for the longer groups) thereof.
• alkenyl are pentenyl, heptenyl, nonenyl, dodecenyl, hexadecenyl, octadecenyl, and isomeric forms thereof.
• the polyurethane foams may be manufactured with smaller amounts of the polyol than- is otherwise required by using a novel catalyst that has as a substituent one or more of the radicals selected from the group including propoxy, ethoxy, or styrene oxide.
• the "B" component mix is a iscible blend having a relatively long shelf life.
• An object of the present invention is thus a method of manufacturing a polyurethane foam using a catalyst that is novel in that it initiates the reaction and also reduces the amount of polyol required for the formation of a given amount of foam.
• This invention concerns rigid polyurethane foams and particularly rigid polyurethane foams which are generally made by reacting. an isocyanate and a hydroxy- terminated or polyhydric compound, i.e., a polyol, in the presence of a surfactant, catalyst and blowing agent.
• "Rigid" polyurethane foams are in contrast to “flexible” foams and “semi-rigid” foams. A good measure of rigidity is not generally available or definable, but the differences between the foams of various rigidities are recognized in the art.
• the polyurethane foams in accordance with the present invention are prepared simply by mixing together, in proportions and ranges specified below, the "A” and “B” components.
• the "B” component comprises a polyhydric alcohol, or a hydroxy-ter inated or polyhydric compound, the catalyst, surfactant, and blowing agent, which is reacted with the "A” component comprising the isocyanate or -NCO containing compound.
• the polyol may thus be selected from a group including, for example: polyalkylene ether glycols, triols, and so forth having up to eight hydroxyl groups; branched-chain polyols of hydroxyl terminated condensation products of propylene oxide or of mixed ethylene and propylene oxides or other alkylene oxides with polyhydric alcohols of 2 to 8 hydroxyl groups such as ethylene glycol, glycerol, pentaerythritol, sorbitol, sucrose, and methyl glucoside; linear polyols such as dipropylene glycol, tripropylene glycol, or polypropylene ether glycol.
• polyalkylene ether glycols triols, and so forth having up to eight hydroxyl groups
• branched-chain polyols of hydroxyl terminated condensation products of propylene oxide or of mixed ethylene and propylene oxides or other alkylene oxides with polyhydric alcohols of 2 to 8 hydroxyl groups such as ethylene
• the surfactant may be selected from the group including silicone glycol copolymers with direct silicone-carbon bonds such as surfactants DC-195 or DC-193, sold by the Dow Corning Corporation. Minor amounts of such conventional surfactants, including silicone oils and soaps and siloxaneoxyalkylene block copolymers, in quantities up to about 2 parts by weight of the surfactant per 100 parts of the polyol, are usef l in improving the cell structure of the polyurethane foam in that they stabilize the cell structure during foam rise and prevent slumping, collapsing, and ripping of the cells.
• the blowing agent also known as the foaming agent, may include many of those known in the art, including fluorocarbons which can be used for blowing polymer mixtures into cellular polymers.
• fluorocarbons which can be used for blowing polymer mixtures into cellular polymers.
• blowing agents are low-boiling (less than 110°C) liquids which vaporize under the influence of the exothermal polymerization reaction and which are inert towards the isocyanate.
• halogenated hydrocarbons such as ethylene chloride, trichlorofluoromethane, dichlorodifluoromethane, dichloromono- fluoromethane, dichlorotetrafluoroethane, ethyl chloride, methylene chloride, chloroform, carbon tetrachloride, and 1,1,2-trichloro-l,2,2-trifluoroethane. Mixtures of these low- boiling liquids and/or mixtures of these liquids with other substituted or unsubstituted hydrocarbons can also be used.
• halogenated hydrocarbons such as ethylene chloride, trichlorofluoromethane, dichlorodifluoromethane, dichloromono- fluoromethane, dichlorotetrafluoroethane, ethyl chloride, methylene chloride, chloroform, carbon tetrachloride, and 1,1,2-trichloro-l,2,2-trifluoroe
• the appropriate amount of low-boiling, liquid blowing agent for the manufacture of foamed polyurethane materials is a function of the desired foam density. Generally, quantities of 5 to 40 percent by weight relative to 100 parts by weight of isocyanate provide satisfactory results. ⁇
• O PI Suitable catalysts include compounds having the formula:
• R4 is either -H, C5H5 ⁇ , -CH2O-C6-H5CH3, or an unsubstituted or halogen substituted C1-C4 alkyl group
• R]_, R2, and R3 are selected from the group including -(CH2CHR4 ⁇ ) x H, and aliphatic radicals having between 1 and 22 carbon atoms, and wherein Y® is an anion.
• Suitable anions for example, may include the borate (H2BO3"-), phosphate (H2P04-), and acetate (CH3COO—) anions.
• Suitable catalysts therefore include the quaternary ammonium compounds: polyoxyethylene (5) cocoammonium borate, which may be obtained from the Ar ak Company (300 South acker Drive, Chicago, Illinois 60606) as Ethoquad® CD/15 Borate; tetraethanol ammonium borate, also known as Armak's Ethoquad® TEA/11 Borate; polyoxyethylene (4) ditallow- ammonium borate, also known as Armak's Ethoquad® 2T/14 Borate; polyoxyethylene (15) cocoammonium borate, available as Armak's Ethoquad® C/25 Borate; methylpolyoxyethylene (15) octadecyl-ammonium borate, available as Armak's Ethoquad® " 18/25 Borate; polyoxyethylene (4) cocoammonium borate, available as Armak's Ethoquad® CD/14 Borate; polyoxyethylene (4) cocoammonium phosphate, available as Armak's Eth
• the "A” component comprises the isocyanate (polyisocyanate) to be reacted with the "B” component.
• suitable isocyanates or reactive -NCO containing compounds which may be employed in practicing the invention include: 2,4-tolylene diisocyanate; diphenylmethane diisocyanate; butylene-l,4-diisocyanate; octamethylene diisocyanate; benzene triisocyanate; 4-bromo-l,3-phenylene- diisocyanate; 4-ethoxy-l,3-phenylene- diisocyanate; 2,4-diisocyanatostilbene; 2,5-fluorenediisocyanate; 2,6-diisocyanatobenzofuran; 2,4,6-toulenetriisocyanate; and other organic pol isocyanates conventionally and previously employed in the art for this purpose.
• Mondur MR is the preferred organic polyisocyanate.
• Mondur MR is a polymeric polyaryl- polyisocyanate prepared by phosgenation of aniline and formaldehyde in a mineral acid.
• the polyisocyanate has 31.5-32% active -NCO groups and a viscosity of about 200 cps at 25°C.
• the general procedure is to weigh in a container, such as an unlined paper cup, the compounds of the "B" component.
• the "B” component will comprise one or more polyols, as for example Voranol® 490, Voranol being the tradename of Dow Chemical Company for polyether polyols; a surfactant, such as Silicone, DC-193, a silicone-glycol copolymer available from Dow Corning; a blowing agent, such as Freon R-ll-A, DuPont's tradename for its trifluorochloro- methane; and the catalyst/co-polyol.
• a co-polyol is a compound contributing to the hydroxy content of the "B" component.
• the compounds comprising the "B" component are then blended together using, for example, a high speed air-driven mixer equipped with a stirrer blade. Some of the blowing agent may be lost by evaporation during blending; the mixer is stopped, additional blowing agent is added until the amount of blowing agent in the blend is back to the desired amount, and the mixer is restarted.
• foams (A, B, and C) manufactured in accordance with the present invention.
• the polyurethane foams were prepared using three different catalyst/co-polyols, namely, either Ethoquad® CD/15 Borate,
• the "NCO/OH ratio" is indicative of the number of equivalents of the isocyanate used per equivalent of polyol.
• the ratio is determined by using the formula: hydroxyl equiv. of isocyanate x weight of isocyanate used
• NCO/OH ratio hydroxyl number of polyol x weight of polyol used
• the "cream time” is also known as the "initiation time”, and is the interval between the blending of the “A” and “B” components and the turning of that mixture to a creamy color or to its commencing to rise or expand.
• the “gel time” is also known as the “string time”, and is the interval between the blending of the "A” and “B” components and the point at which it is possible to draw a five to ten inch-long string or whisker when the surface of the foam is touched with a wooden spatula.
• “rise time” is the interval between the blending of the "A” and “B” components and the time at which the foam stops rising in an open container. As the last few percent of this rise may be time-consuming and difficult to discern, a “95% rise time” is sometimes quoted.
• “Tack-free time” is the interval between the blending of the "A” and “B” components and the time a wooden spatula touched to the foam surface no longer sticks to it.
• Component B is a compound having Component B:
• Component B is a compound having Component B:
• foams (F-H) were prepared in accordance with the general procedures set forth hereinabove, using Ethoquad® CD/15 Borate as the catalyst/co-polyol. TABLE 3
• Component B is a compound having Component B:
• the hydroxyl content is maintained by using a fixed weight of polyol and catalyst.
• the sum of the mass of polyol and catalyst was a constant 132.9 +/- 0.1 g.
• the tack-free time dropped significantly.
• foams (I-J) were prepared in accordance with the general procedures set forth hereinabove, using Ethoquad® CD/14 Borate and Ethoquad® CD/14 Phosphate as the catalyst/co-polyol.
• Component B is a compound having Component B:
• foams (Q and R) were manufactured in accordance with the general procedures set forth herein- above, except that foam Q used a conventional catalyst instead of the present catalyst.
• Foam R used a reduced amount of the polyol Voranol 575; the reduction was on a one-for-one basis, i.e., for each gram of Ethoquad® T/14 Borate used in Foam R, one gram less of Voranol 575 (as compared with Foam Q) was used.
• Voranol 575 A one-for-one reduction of Voranol 575 was made because the hydroxyl number of Ethoquad® T/14 Borate (600) is virtually identical to that of Voranol 575 (604); hence, a one-for-one substitution retains constant both the hydroxyl content of the blend and the NCO/OH ratio.
• Polycat 8 is a di e thylcyclohexylamine .
• Polycat is a tradename of Abbott Laboratories .
• the mass of foam formed remains approximately constant when a conventional, prior art catalyst is replaced by the present catalyst and the amount of polyol reduced by the amount of the present catalyst/co-polyol added.
• the present catalyst therefore replaces a conventional catalyst and reduces the amount of polyol required with no loss in foam production.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Polyurethanes Or Polyureas (AREA)

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• 1983
  • 1983-03-25 EP EP19830901532 patent/EP0104251A4/fr not_active Withdrawn
  • 1983-03-25 JP JP50162183A patent/JPS59500521A/ja active Pending
  • 1983-03-25 WO PCT/US1983/000453 patent/WO1983003415A1/fr not_active Application Discontinuation

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