||||||||IHIII US005 130345A United States Patent (19) 11) Patent Number: 5,130,345 Li et al. 45) Date of Patent: Jul. 14, 1992

(54) METHOD OF PREPARING FOAM USINGA 4,529,744 7/1985 Wood ...... 521/1.31 PARTIALLY FLUORINATED ALKANE 4,624,970 1 1/1986 Dwyer et al...... 521/13 HAVING ATERTARY STRUCTURE ASA OTHER PUBLICATIONS BLOWENGAGENT "The Perfluoro-ta-butyl Anion in the Synthesis of 75) Inventors: Chien C. Li, East Aurora, NY; Organofluorine Compounds"-Dyatkin et al. pard Sukornick, Cooper City, "How to Fix the CFC Mix', Chemicalweek/Oct. 18, 1989. 73) Assignee: AlliedSignal Inc. Morris Township, Pina Examiner-John Kight, III Morris County, N.J. Assistant Examiner-John M. Cooney, Jr. (21) Appl. No.: 546,173 Attorney, Agent, or Firm-Melanie L. Brown; Jay P. (22 Filed: Jun. 29, 1990 Friedenson CT 51 int.C.' ...... co8J 9/14; cosGC08G 18/00,18/06 A method for ABSTRApreparing polyurethane and 52 U.S.C...... 521/131; 521/98; polyisocyanurate foams which comprises reacting and 521/155; 52 1/163.521/170 foaming a mixture of ingredients which will react to (58) Field of Search ...... 521/131,98, 155, 163, form the polyurethane or polyisocyanurate foams in the 52/170 presence of a blowing agent comprising a partially fluo 5 C rinated alkane having four or five carbon atoms and a (56) References Cited tertiary structure. The method is advantageous because U.S. PATENT DOCUMENTS partially fluorinated alkanes having a tertiary structure 3,183,92 5/1965 Bauer ...... sy have zero ozone depletion potentials, are nonflamma

4,076,644 2/1978 Burnt et al. .... 521/1.31 ble, and have higher solvency toward polyols. 4,177,332 12/1979 Mitschke et al. .. m 521/13 4,417,00 1 1/1983 Suoboda et al...... 521/13 10 Clains, No Drawings 5,130,345 1. 2 earth's protective ozone layer. CFC-11 and CFC-12 are METHOD OF PREPARING FOAM USINGA controlled substances under the Montreal Protocol on PARTIALLY FLUORINATED ALKANE HAVING A Substances that Deplete the Ozone Layer. Mathemati TERTARY STRUCTURE ASA BLOWINGAGENT cal models have substantiated that hydrochlorofluoro carbons are negligible contributors to ozone depletion FIELD OF THE INVENTION and to green-house global warming in comparison to This invention relates to a method of preparing foam the fully halogenated species. using a partially fluorinated alkane having four or five As discussed in "How to Fix the CFC Mix', CHEM carbon atoms and a tertiary structure as the blowing ICAL WEEK 64 (Oct. 18, 1989), alternative blowing agent. O agents for currently used CFC blowing agents include chlorodifluoromethane (known in the art as HCFC-22 CROSS-REFERENCE TO RELATED and which has a boiling point of -40.8 C.), 1,1- APPLICATION dichloro-2,2,2-trifluoroethane (known in the art as Commonly assigned, U.S. Pat. No. 5,059,728 claims HCFC-123 and which has a boiling point of 27.8' C.), partially fluorinated alkanes having a tertiary structure 15 1-chloro-1,2,2,2-tetrafluoroethane (known in the art as and 4 to 9 carbon atoms. HCFC-124 and which has a boiling point of -12 C.), 1,1-dichloro-1-fluoroethane (known in the art as BACKGROUND OF THE INVENTION HCFC-141b and which has a boiling point of 32 C.), The art is continually seeking new fluorocarbons and 1-chloro-1,1-difluoroethane (known in the art as which are useful as blowing agents. Fluorocarbons such 20 HCFC-142b and which has a boiling point of -9.2 C.). as trichlorofluoromethane (known in the art as CFC-11 The use of HCFC-123 as a blowing agent is disadvan and which has a boiling point of 23.7 C.) have been tageous because HCFC-123 has a high molecular used commercially as auxiliary blowing agents for flexi weight; as a result, HCFC-123 is an inefficient blowing ble foams and as primary blowing agents for rigid agent. The use of HCFC-141b or HCFC-142b as a foams. Polyurethane foams are manufactured by react 25 ing and foaming a mixture of ingredients comprising in blowing agent is disadvantageous because the vapors of general an organic isocyanate, such as pure or crude HCFC-141b and HCFC-142b are flammable; as a result, toluene diisocyanate or a polymeric diisocyanate, with the shipping, handling, and use of HCFC-141b and an appropriate amount of polyol or mixture of polyols, HCFC-142b have to be carefully controlled due to the in the presence of a volatile liquid blowing agent, which 30 potential flammability. The use of HCFC-22 and vaporizes during the reaction, causing the polymerizing HCFC-124 as blowing agents is disadvantageous be mixture to foam. The reactivity of these ingredients is cause they have such low boiling points. enhanced through the use of various additives such as U.S. Pat. No. 4,624,970 discloses the use of mixtures amine and/or tin catalysts and surfactant materials of CFC-11 and dichlorotrifluoroethane to blow ure which serve to control and adjust cell size as well as to 35 thane type foams. Such blowing agent mixtures were stabilize the foam structure during its formation. found to permit greater amounts of low cost aromatic Flexible polyurethane foams are generally manufac polyester polyols to be used in rigid foam formulations tured using an excess of diisocyanate which reacts with without serious degradation in foam properties. the water also included as a raw material, producing Although hydrochlorofluorocarbon blowing agents gaseous carbon dioxide, causing foam expansion. Flexi have low ozone depletion potentials compared with the ble foams are widely used as cushioning materials in fully halogenated chlorofluorocarbons, a need exists in items such as furniture, bedding and automobiles. Auxil the art for a method of preparing foam with a blowing iary physical blowing agents such as methylene chlo agent which has a zero ozone depletion potential and is ride and/or CFC-11 are required in addition to the nonflammable. water/diisocyanate blowing mechanism in order to 45 It is an object of this invention to provide a method produce low density, soft grades of flexible polyure for the preparation of polyurethane and polyisocyanu thane foam. rate foams. Rigid polyurethane foams are almost exclusively A further object of the invention is to provide envi expanded using CFC-11 as the blowing agent. Some ronmentally acceptable blowing agents for the produc rigid foam formulations do incorporate small amounts tion of rigid and flexible polyurethane and of water in addition to the CFC-11, but the CFC-11 is the major blowing agent component. Other formula polyisocyanurate foams. tions sometimes use small amounts of the more volatile SUMMARY OF THE INVENTION dichlorodifluoromethane (known in the art as CFC-12 The present invention fills the need in the art by and which has a boiling point of -29.8' C.) in addition 55 providing a method of forming polyurethane and to CFC-11 for producing so-called froth-type foams. polyisocyanurate foams by reacting and foaming a mix Rigid foams are closed-cell foams in which the CFC-11 vapor is trapped in the matrix of cells. These foams offer ture of ingredients which will react to form polyure excellent thernal insulation characteristics, due in part thane and polyisocyanurate foams in the presence of a to the low vapor thermal conductivity of CFC-11, and 60 blowing agent comprising a partially fluorinated alkane are used widely in thermal insulation applications such having four or five carbon atoms and a tertiary struc as roofing systems, building panels, refrigerators and ture. The phrase "tertiary structure' as used herein freezers and the like. means a structure with one carbon having three alkyl Currently, fluorocarbons are of particular interest groups and one hydrogen thereon. This method is ad because they are considered to be stratospherically safe 65 vantageous because partially fluorinated alkanes having substitutes for the presently used fully halogenated this tertiary structure have higher solvency toward chlorofluorocarbons. The latter are suspected of caus polyols in addition to having zero ozone depletion po ing environmental problems in connection with the tentials and being nonflammable. 5,130,345 3 4. Other objects and advantages of the invention will may then be hydrogenated to form 2-fluoromethyl become apparent from the following description. 1, 1,4,4-tetrafluorobutane. Preferably, each R in the Formula above is the same. DETALED DESCRIPTION OF THE When each R is CHF2 and R' is CF3, the compound is PREFERRED EMBODIMENTS 2-difluoromethyl-1,1,1,3,3-pentafluoropropane. When Preferably, in the present method, the blowing agent each R is CHF2 and R' is CH2F, the compound is 2 comprising a partially fluorinated alkane having four or fluoromethyl-1,1,3,3-tetrafluoropropane. When each R five carbon atoms and a tertiary structure is of the For is CHF2 and R' is CH3, the compound is 2-methyl mula: 1,1,3,3-tetrafluoropropane. When each R is CH2F and R" is CHF2, the compound is 2-fluoromethyl-1,1,3-tri fluoropropane. The 2-difluoromethyl-1,1,1,3,3-pentafluoropropane may be prepared by fluorinating commercially available 1,1,1,3,3-pentachloro-2-propanone to form 1,1,1,3,3- 15 pentafluoro-2-propanone which may then be reacted wherein each R is the same or different and is selected with CF2 carbene to form 2-difluoromethyl-1,1,3,3,3- from the group consisting of CF3, CHF2, CH2F, and tetrafluoro-1-propene. The 2-difluoromethyl-1,1,3,3,3- CH3CF2-, and R' is selected from the group consisting tetrafluoro-1-propene may then be hydrogenated to of CF, CHF2, CH2F, CH3, CFCF2-, CF3CHF-, form 2-difluoromethyl-1,1,1,3,3-pentafluoropropane. CF3CH2-, CHFCF2, CHF2CHF-, CHF2CH2-, 20 The 2-fluoromethyl-1,1,3,3-tetrafluoropropane may CH2FCF-, CH2FCHF-, CH2FCH2-, CH3CF2-, be prepared by fluorinating commercially available and CH3CHF- with the proviso that when one of the 1,1,3-trichloro-2-propanone to form 1,1,3-trifluoro-2- three alkyl groups has two carbons, each of the other propanone which may then be reacted with CF2 car two alkyl groups has one carbon. bene to form 2-difluoromethyl-1,1,3-trifluoro-1-pro Illustrative examples of the blowing agents follow. In 25 pene. The 2-difluoromethyl-1,1,3-trifluoro-1-propene the Formula above, when one R is CF3, the other R is may then be hydrogenated to form 2-fluoromethyl CHF2, and R' is CH3, the compound is 2-methyl 1,1,3,3-tetrafluoropropane. 1,1,1,3,3-pentafluoropropane. When one R is CF3, the As another example, 2-methyl-1,1,3,3-tetrafluoropro other R is CHF, and R' is CH3, the compound is 2 pane may be prepared by fiuorinating commercially methyl-1,1,1,3-tetrafluoropropane. When one R is CF3, 30 the other R is CH2F, and R' is CHF2CHF-, the com available 1,1-dichloro-2-propanone to form 1,1- pound is 2-fluoromethyl-1,1,1,3,4,4-hexafluorobutane. difluoro-2-propanone which may then be reacted with When one R is CHF2, the other R is CH2F, and R' is CF2 carbene to. form 2-difluoromethyl-1,1-difluoro-1- CH3, the compound is 2-methyl-1,1,3-trifluoropropane. propene. The 2-difluoromethyl-1,1-difluoro-1-propene When one R is CHF2, the other R is CH2F, and R' is 35 may then be hydrogenated to form 2-methyl-1,1,3,3-tet CHF2CH2-, the compound is 2-fluoromethyl-1,1,4,4- rafluoropropane. tetrafluorobutane. As another example, the 2-fluoromethyl-1,1,3-tri The novel compounds used in the present method fluoropropane may be prepared by oxidizing commer may be prepared by adapting known methods for pre cially available 1,3-difluoro-2-propanol to 1,3-difluoro paring hydrofluorocarbons. For example, 2-methyl 2-propanone which may then be reacted with a CF2 1,1,1,3,3-pentafluoropropane may be prepared by react carbene to form 2-fluoromethyl-1,1,3-trifluoro-1-pro ing commercially available 1,1,1-trifluoro-2-propanone pene. The 2-fluoromethyl-1,1,3-trifluoro-1-propene with CF2 carbene to form 2-trifluoromethyl-1,1- may then be hydrogenated to form 2-fluoromethyl difluoro-1-propene which may then be hydrogenated to 1,1,3-trifluoropropane. form 2-methyl-1,1,1,3,3-pentafluoropropane. 45 More preferably in the Formula above, each R is As another example, 2-methyl-1,1,1,3-tetrafluoropro CF3 and R' is selected from the group consisting of CF3, pane may be prepared by reacting commercially avail CHF2, CH3, CF3CF2-, CF3CHF-, and CHF2CH2-. able methacrylic acid with hydrogen fluoride to form The names of the preceding preferred hydrofluorocar 2-methyl-3-fluoropropanoic acid which may then be bons are 2-trifluoromethyl-1,1,1,3,3,3-hexafluoropro fluorinated to form 2-methyl-1,1,1,3-tetrafluoropro pane; 2-difluoromethyl-1,1,1,3,3,3-hexafluoropropane; pane. 2-methyl-1,1,1,3,3,3-hexafluoropropane; 2-tri As another example, 2-fluoromethyl-1,1,1,3,4,4-hexa fluoromethyl-1,1,1,3,3,4,4,4-octafluorobutane; 2-tri fluorobutane may be prepared by fluorinating commer fluoromethyl-1,1,1,3,4,4,4-hexafluorobutane; and 2-tri cially available 3-chloropropionic acid to form 1,1,1,3- fluoromethyl-1,1,1,4,4-pentafluorobutane. tetrafluoropropane which may then be reacted with 55 The 2-trifluoromethyl-1,1,1,3,3,3-hexafluoropropane CHF2CF carbene to form 2-fluoromethyl-1,1,1,3,4,4- of the present invention is known. It may be prepared hexafluorobutane. by any known method including reacting commercially As another example, 2-methyl-1,1,3-trifluoropropane available hexafluoropropene with hydrogen fluoride to may be prepared by reacting commercially available form 1,1,1,2,3,3,3-heptafluoropropane which may then fluoroacetone with a CF2 carbene to form 2 be heated at 475'-700' C. in the presence of activated fluoromethyl-1,1-difluoro-1-propene which may then carbon as taught by commonly assigned U.S. Pat. No. be hydrogenated to form 2-methyl-1,1,3-trifluoropro 2,981,763 which is incorporated herein by reference; or pane. As another example, 2-fluoromethyl-1,1,4,4-tetra reacting perfluoroisobutene with hydrogen fluoride in fluorobutane may be prepared by oxidizing commer the presence of catalytic amounts of ammonium fluo cially available 3-fluoro-1,2-propanediol to form a prod 65 ride or triethylamine as taught by B. L. Dyatkin et al., uct which may then be reacted with a CF2 carbene to "The Perfluoro-t-butyl Anion in the Synthesis of Or form 2-fluoromethyl-1,1,4,4-tetrafluoro-1,3-butadiene; ganofluorine Compounds", RUSSIAN CHEMICAL the 2-fluoromethyl-1,1,4,4-tetrafluoro-1,3-butadiene REVIEWS 45(7), 607 (1976). 5,130,345 5 6 As another example, 2-difluoromethyl-1,1,1,3,3,3- 2-trifluoromethyl-1,1,1,3,3,3-hexafluoropropane may be hexafluoropropane may be prepared by treating com used as a replacement for CFC-11. mercially available hexafluoropropene with hydrogen The use of 2-methyl-1,1,1,3,3,3-hexafluoropropane is fluoride as taught by commonly assigned U.K. Patent advantageous in the present method because 2-methyl 902,590 to form 1,1,1,2,3,3,3-hexafluoropropane. The 1,1,1,3,3,3-hexafluoropropane has a zero ozone deple 1,1,1,2,3,3,3-hexafluoropropane may then be heated at tion potential, is nonflammable, and has a boiling point 475-700' C. in the presence of activated carbon as which is calculated to be about 30' C. As such, 2-meth taught by commonly assigned U.S. Pat. No. 2,981,763 yl-1,1,1,3,3,3-hexafluoropropane may be used as a re which is incorporated herein by reference to form 2-tri placement for CFC-11. fluoromethyl-1,1,1,3,3,3-hexafluoropropane or nona O Other methods for preparing the partially fluorinated fluoroisobutane. The nonafluoroisobutane may then be alkanes are disclosed in commonly assigned U.S. Pat. treated with commercially available benzoyl chloride in No. 5,059,728 which is incorporated herein by refer the presence of commercially available triethylamine as eace. taught by B. L. Dyatkin et al., "The Perfluoro-t-butyl The partially fluorinated alkane having a tertiary Anion in the Synthesis of Organofluorine Compounds", 15 structure may be used as an auxiliary or primary blow Russian Chemical Reviews 45(7), 607 (1976) to form ing agent for the preparation of polyurethane foams. perfluoroisobutene. The perfluoroisobutene may then Polyurethanes are polymers of polyols and isocyanates. by hydrogenated to form 2-difluoromethyl-1,1,1,3,3,3- A wide variety of polyols may be employed as disclosed hexafluoropropane. in the prior art, such as polyether polyols and polyester As another example, 2-methyl-1,1,1,3,3,3-hexafluoro 20 polyols. Illustrative suitable polyether polyols are poly propane may be prepared by reacting commercially oxypropylene diols having a molecular weight of be available hexafluoropropene with elemental sulfur and tween about 1,500 and 2,500, glycerol based polyoxy commercially available potassium fluoride in commer propylene triols having a molecular weight of between cially available dimethylformamide under substantially about 1,000 and 3,000, trimethylol-propane-based triols atmospheric pressure and at temperatures between 25 having a hydroxyl number of about 390, sorbitol-based 25'-100' C. as taught by commonly assigned U.S. Pat. hexol having a hydroxyl number of about 490, and No. 4,326,068 which is incorporated herein by reference sucrose-based octols having a hydroxyl number of to form hexafluorothioacetone dimer. The hexafluoro about 410. Illustrative suitable polyester polyols are the thioacetone dimer may than be reacted with commer reaction products of polyfunctional organic carboxylic cially available formaldehyde as taught by commonly 30 acids such as succinic acid, adipic acid, phthalic acid assigned U.S. Pat. No. 4,367,349 which is incorporated and terephthalic acid with monomeric polyhydric alco herein by reference to form hexafluoroisobutylene. The hols such as glycerol, ethylene glycol, trimethylol pro hexafluoroisobutylene may then be hydrogenated to pane, and the like. form 2-methyl-1,1,1,3,3,3-hexafluoropropane. A wide variety of isocyanates may be employed as As another example, 2-trifluoromethyl-1,1,1,3,3,4,4,4- 35 disclosed in the prior art. Illustrative suitable isocya octafluorobutane may be prepared by reacting caesium nates are the aliphatic isocyanates such as hexamethyl fluoride and perfluoro-3-methylbut-1-ene in moist sul ene diisocyanate, aromatic isocyanates such as toluene pholan as taught by Robert N. Haszeldine et al., "Fluo diisocyanate (TDI), preferably the isomeric mixture ro-olefin Chemistry. Part 11. Some Reactions of Per containing about 80 weight percent of the 2,4 isomer fluoro-3-methylbut-1-ene under Ionic and Free-radical and 20 weight percent of the 2,6 isomer, crude TDI, Conditions", J. Chem. Soc. 565 (1979). crude diphenylmethane diisocyanate and polymethyl As another example, 2-trifluoromethyl-1,1,1,3,4,4,4- polyphenyl isocyanate. hexafluorobutane may be prepared by reacting com The amount of partially fluorinated alkane having a mercially available 1,1-difluoroethylene according to tertiary structure to be employed as the blowing agent the procedure of George L. Fleming et al., "Addition of 45 will depend on whether it is to be used as a primary or Free Radicals to Unsaturated Systems. Part XX. The auxiliary blowing agent and the nature of the foams Direction of Radical Addition of Heptafluoro-2-iodo desired, i.e., whether flexible or rigid foam is desired. propane to Vinyl Fluoride, Trifluoroethylene, and The amount of partially fluorinated alkane having a Hexafluoropropene", J.C.S. Perkin I, 574 (1973) to form tertiary structure employed as the blowing agent can be a product which may then be fluorinated to form 2-tri readily determined for each foaming system by persons fluoromethyl-1,1,1,2,3,4,4,4-octafluorobutane. The 2 of ordinary skill in the art. Generally, about 1 to about trifluoromethyl-1,1,1,2,3,4,4,4-octafluorobutane may 15 weight percent based on the polyurethane forming then be dehydrohalogenated and then hydrogenated to reaction mixture of the blowing agent is employed and form 2-trifluoromethyl-1,1,1,3,4,4,4-hexafluorobutane. preferably, between about 5 to about 10 weight percent. As another example, 2-trifluoromethyl-1,1,1,4,4-pen 55 As is well known in the art, the urethane-forming tafluorobutane may be prepared by reacting commer reaction requires a catalyst. Any of the well known cially available 1,1-difluoroethylene according to the urethane-forming catalysts may be employed. Illustra procedure of George L. Fleming et al., supra, to form a tive organic catalysts are the amino compounds such as product which may then be hydrogenated to form 2-tri triethylenediamine N,N,N',N'-tetramethylethylenedia fluoromethyl-1,1,1,2,4,4-hexafluorobutane which may mine, dimethylethanolamine, triethylamine and N then be dehydrohalogenated and then hydrogenated to ethyl-morpholine. Inorganic compounds such as the form 2-trifluoromethyl-1,1,1,4,4-pentafluorobutane. non-basic heavy metal compounds as illustrated by The use of 2-trifluoromethyl-1,1,1,3,3,3-hexafluoro dibutyl tin dilaurate, stannous octoate and manganese propane is advantageous in the present method because acetyl acetonate may also be used as catalysts. In gen 2-trifluoromethyl-1,1,1,3,3,3-hexafluoropropane has a 65 eral, the amount of catalyst present in the foam forming zero ozone depletion potential, is nonflammable, and mixture ranges from about 0.05 to about 2 parts by has a reported boiling point of 11-12" C. according to weight per 100 parts by weight of the polyol compo commonly assigned U.S. Pat. No. 2,981,763. As such, ment. 5,130,345 7 8 As is well recognized in the art, a variety of other additives may be incorporated in the foam-forming TABLE I-continued mixtures including stabilizers, such as silicone oils; Example R R cross-linking agents such as 1,4-butanediol, glycerol, 22 CF, CHF CFCH2 23 CF, CHF CHFCF2 triethanolamine methylenedianiline; plasticizers, such as 24 CF, CHF CHFCHF tricresyl phosphate and dioctyl phthalate; antioxidants; 25 CF, CH2F CHFCH fame retardants; coloring material; fillers; and antis 26 CF, CHF CHFCF corch agents. 27 CF3, CHF CHFCHF 28 CF, CHF CHFCH Polyurethane foams are prepared according to the 29 CF, CHF CH3CF invention by reacting and foaming a mixture of ingredi O 30 CF, CHF CH3CHF ents which will react to form the foams in the presence 31 CF, CH3CF, CFs of the blowing agent, a partially fluorinated alkane 32 CF, CH3CF CHF: 33 CF, CH3CF CH2F having a tertiary structure, according to the invention. 34 CF, CH3CF2 CH3 In practice, the foam forming ingredients are blended, 35 CHF, CH2F CF allowed to foan, and are then cured to a finished prod 15 36 CHF, CHF CHF uct. The foaming and curing reactions, and conditions 37 CHF, CHF CHF therefor are well-known in the art and do not form a 38 CHF, CHF CH3 39 CHF, CH2F CFCF part of this invention. Such are more fully described in 40 CHF CHF CFCHF the prior art relating to the manufacture of polyure 41 CHF, CHF CFCH thane foams. Thus, for example, the polyether may first 20 42 CHF, CHF CHFCF be converted to a polyether-polyisocyanate prepolymer 43 CHF2, CHF CHFCHF 44 CHF, CHF CHFCH by reaction in one or more stages with an excess amount 45 CHF, CHF CHFCF of isocyanate at temperatures from about 75-125 C. or 46 CHF, CH2F CHFCHF by reacting the polyol and the isocyanate together at 4. CHF2, CHF CHFCH room temperature in the presence of a catalyst for the 25 48 CHF2, CH2F CH3CF 49 CHF CHF CH3CHF reaction such as N-methylmorpholine. The prepolymer SO CHF2, CH3CF, CF3 would then be charged to the foam-forming mixture as 51 CHF2, CH3CF CHF the foam producing ingredient with or without the 52 CHF2, CH3CF CHF addition of additional isocyanate and foamed in the 53 CHF2, CH3CF2 CH3 30 S4 CHF, CH3CF, CFs presence of the blowing agent, optionally with addi 55 CHF, CH3CF CHF tional polyol cross-linking agents and other conven 56 CH2F, CH3CF2 CHF tional optional additives. Heat may be applied to cure 57 CHF, CH3CF, CH3 the foam. If a prepolymer is not employed, the poly 58 CF, CFs CF3 ether, isocyanate, partially fluorinated alkane having a 59 CF, CFs CHF 35 60 CF, CF CHF tertiary structure blowing agent, and other optional 6 CF, CF CH3 additives may be reacted simultaneously to produce the 62 CF, CF CFCF foam in a single stage. 63 CF, CFs CFCHF A premix of the polyol and partially fluorinated al 64 CF, CF3 CF3CH2 65 CF, CF CHFCF kane having a tertiary structure blowing agent may also 66 CF, CF3 CHFCHF be used. This premix has enhanced stability due to the 67 CF, CF CHFCH2 partially fluorinated alkane having a tertiary structure. 68 CF, CF CHFCF The present invention is more fully illustrated by the 69 CF, CF CH2FCHF following non-liniting Examples. 70 CF, CF3 CH2FCH2 7 CF, CF CH3CF EXAMPLES 1-102 72 CF, CF CH3CHF 45 73 CHF2, CHF CF A rigid polyurethane foam is prepared by using each 4. CHF, CHF CHF 75 CHF, CHF CHF of the blowing agents of the Formula above having the 76 CHF CHF CH3 R and R' groups as indicated in Table I below. 77 CHF, CHF CFCF TABLE I 78 CHF, CHF CFCHF 79 CHF, CHF CFCH Example R R 80 CHF, CHF CHFCF CF, CHF CF 8 CHF, CHF CHFCHF 2 CF, CHF CHF 82 CHF, CHF CHFCH 3 CF, CHF CHF 83 CHF, CHF CHFCF 4. CF, CHF CH3 84 CHF CHF CHFCHF s CF, CHF CFCF 55 85. CHF, CHF CH2FCH 6 CF, CHF CFCHF 86 CHF, CHF CHCF 7 CF, CHF CFCH 87 CHF, CHF CHCHF 8 CF, CHF CHFCF 88 CH2F, CHF CF 9 CF, CHF CHFCHF 89 CHF, CHF CHF O CF, CHF CHFCH 90 CH2F, CHF CHF CF, CHF CHFCF 91 CHF, CHF CH3 2 CF, CHF CHFCHF 92 CHF, CHF CFCF 3 CF, CHF CHFCH 93 CH2F, CHF CFCHF 4. CF, CHF CH3CF2 94 CHF, CH2F CFCH2 15 CF, CHF CH3CHF 95 CH2F, CHF CHFCF 16 CF, CHF CF 96 CH2F, CHF CHFCHF 7 CF3, CHF CHF 65 97 CH2F, CHF CHFCH 8 CF, CH2F CHF 98 CH2F, CH2F CHFCF 9 CF3, CH2F CH3 99 CH2F, CHF CHFCHF 20 CF, CHF CFCF 100 CH2F, CHF CH2FCH2 21 CF, CHF CFCHF 0. CHF, CHF CH3CF2 5,130,345 9 10 foaming a mixture of ingredients which will react to TABLE I-continued form the polyurethane and polyisocyanurate foams in Example R R the presence of a blowing agent comprising a partially O2 CHF, CHF CH3CHF fluorinated alkane having four or five carbon atoms and a tertiary structure wherein said partially fluorinate Free-rise rigid polyurethane foam is prepared from alkane has the formula the formulation specified in Table II below using a Martin Sweets Co. Modern Module III urethane foam machine at a delivery rate of 15 lbs./min. This polyure thane formulation is one example of a pour-in-place 10 rigid polyurethane formulation which might be used as an appliance insulation. wherein each R is the same or different and is selected TABLE II from the group consisting of CF3, CHF2, CH2F, and Rigid Polyurethane Formulation 15 CH3CF2-, and R' is selected from the group consisting Component Parts by Weight of CF, CHF, CH2F, CH3, CFCF-, CF3CHF-, Pluracol 1114 (420-OH #) 00. CF3CH2-, CHF2CF2-, CHF2CHF-, CHF2CH2-, (trademark) CH2FCF-, CH2FCHF-, CH2FCH2-, CH3CF2-, Silicone L-5340 1.5 Thancat TD-33 0.5 and CH3CHF- with the proviso that when one of the (trademark) 20 three alkyl groups has two carbons, each of the other Thancat DME 0.2 two alkyl groups has one carbon. (tradenark) 2. The method of claim 1 wherein each R of said Catalyst T-12 0. Blowing Agent 33.24. partially fluorinated alkane is the same. Lupranate M20S6 (1.29 Index) 29. 3. The method of claim 2 wherein each R of said (trademark) 25 partially fluorinated alkane is CF3. BASF Wyandotte Corp. . polyether polyol 4. The method of claim 1 wherein said partially fluo Union Carbide Corp. - silicone surfactant Texaco Inc. .33% triethylene diamine in propylene glycol rinated alkane is selected from the group consisting of Texaco Inc. - N,N-dimethylethanolamine 2-difluoromethyl-1,1,1,3,3,3,-hexafluoropropane; 2 Metal & Thermit Co.. dibutyl dilaurate methyl-1,1,1,3,3,3-hexafluoropropane; 2-trifluorometh BASF Wyandotte Corp. - polymethylene polyphenylisocyanate 30 yl-1,1,1,3,4,4,4-hexafluorobutane; and 2-trifluorometh yl-1,1,1,4,4-pentafluorobutane. EXAMPLES 103-204 5. The method of claim 1 wherein said blowing agent is 2-methyl-1,1,1,3,3,3-hexafluoropropane, A flexible polyurethane foam is prepared by using 6. A premix of a polyol and a blowing agent compris each of the blowing agents of the Formula above hav 35 ing the R and R" groups as indicated in Table I above. ing a partially fluorinated alkane having four or five Free-rise flexible polyurethane foam is prepared from carbon atoms and a tertiary structure wherein said par the formulation specified in Table III below using a tially fluorinated alkane has the formula Martin Sweets Co. Modern Module III urethane foam machine at a delivery rate of 15 lbs./min. This polyure thane formulation is one example of a formulation which might be used in furniture. TABLE III Flexible Polyurethane Formulation wherein each R is the same or different and is selected Component Parts by Weight 45 from the group consisting of CF3, CHF2, CH2F, and Pluracol 924 100. CH3CF2-, and R' is selected from the group consisting (trademark) of CF3, CHF2, CH2F, CH3, CF3CF2-, CF3CHF-, Water 3.5 Silicone DC-190 1.5 CF3CH2-, CHF.CF2, CHF2CHF-, CHF2CH2-, Thancat TD-33 0.3 CH2FCF-, CH2FCHF-, CH2FCH2-, CH3CF2-, (trademark) and CH3CHF- with the proviso that when one of the Dabco T-9 0. three alkyl groups has two carbons, each of the other Blowing Agent S.0 Lupranate T-80 (1.05 index) 43.7 two alkyl groups has one carbon and with the proviso (trademark) that when each R is CF3, R' is not CF3CF2- or CF3. BASF Wyandotte Corp.. polyether polyol 55 7. The premix of claim 6 wherein each R of said Union Carbide Corp. . silicone surfactant partially fluorinated alkane is the same. Texaco Inc. - 33% triethylene diamine in propylene glycol Air Products - stannous-2-ethylhexoate 8. The premix of claim 7 wherein each R of said BASF Wyandotte Corp. - polymethylene polyphenylisocyanate partially fluorinated alkane is CF3. 9. The premix of claim 6 wherein said partially fluori Having described the invention in detail and by refer nated alkane is selected from the group consisting of ence to preferred embodiments thereof, it will be appar 2-difluoromethyl-1,1,1,3,3,3,-hexafluoropropane; 2 ent that modifications and variations are possible with methyl-1,1,1,3,3,3-hexafluoropropane; 2-trifluorometh out departing from the scope of the invention defined in yl-1,1,1,3,4,4,4-hexafluorobutane; and 2-trifluorometh the appended claims. yl-1,1,1,4,4-pentafluorobutane. What is claimed is: 10. The premix of claim 6 wherein said blowing agent 1. A method for preparing polyurethane and 65 is 2-methyl-1,1,1,3,3,3-hexafluoropropane. polyisocyanurate foams which comprises reacting and k