PRODUCT REVIEW
Flame Retardation of Polyurethane Foams in Practice Anthony J. Papa Research and Development Department, Chemicals and Plastics Division, Union Carbide Cmp., South Charleston, W.Va. 96305
Purdne University and worked o,t D u Pontforj5ve years. He has had experience in the areas of fire-resistant polyurethanes, polyurethane foams, synthetic leather, phenolic resins and foams, acylic coatings, and hightemperature polymers.
L i t t l e information has been published describing the flame retardation of polyurethane foams in practice, and most such data are contained in the patent literature. The lack of such information is not surprising, especially, for example, when compared to flameretarding textiles or polyesters, since the commercial production of urethane polymers has become of importance only within about the past 10 years. Figures 1 and 2 illustrate the US.consumption of flameretarded foam as a function of the total domestic consumption from 1962 t o 1970 for rigid and flexible foams, respectively (62, 64-69). During this period rigid foams have been traditionally flame retarded, such modifications accounting for roughly 50% of foam sold. There are several reasons for this, some of which are indefinite. Perhaps utility in areas where low flammability specifications had been set up for some time, e.g., the construction, transportation, and refrigeration industries are part of the reason. On the other hand, there has been little incentive for developing flame-retardant flexihle foams. Only recently have the bedding and transportation industries talked much about setting flameretardant standards. As a result, the growth of flame-retardant flexihle foams has not been especially rapid. However, i t is likely that virtually all flexible foam will be flame retardant t o some extent by 1975. Recent passing of Motor Vehicle Safety Standard No. 302 by the Department of Transportation and activity on setting bedding standards within the Department of Commerce attest t o the concern. The problem of flameretarding polyurethane foams has attracted the attention of many investigators whose results in this field have been summarized in previous reviews (56, 47, 76,84,88). The present review consists basically of two parts. I n the first part, an attempt is made t o classify techniques leading to flame-retardant rigid polyurethanes. In the second, the major types of flame retardants in actual commercial use are covered for both rigid and flexible foams, and an effort is made t o describe the present state of our knowledge of the subject. Flane Tesh
For practical purposes, today's polyurethane foam market emphasizes comparative flame retardancy by several imInd. Eng. Chem. Pmd. Res. Develop., Vol. 11, No. 4, 1972
379
Table 1. Foam Categories from Flammability Ratings
Rigid foams Approach
x
I IS6
100
I
KEY
MVSS Approach
FR Foam
0
Non- FR Foam
L n I >
300
>
> > Flexible Foams
I
I
UL Tunnel
CH,N(CH,CH,OH 1
)2
2
Based on patents issued, other products (51) may be based on analogous chemistry (20,58). Another technique t o aromatic polyols involves direct alkoxylation of the free-amine precursors to polymeric isocyanates. A recent patent issued to Upjohn Co. claims attractive polyols of this type (73). Generally speaking, aromaticderived polyols provide highstrength rigid foams; however, their typically high viscosities have limited their use to formulated systems. For example, diluted blends offer a route to circumvent this problem, but i t detracts from the desirable performance characteristics of the aromatic polyols. Flame-Retarding Flexible Foams
With the issuance of the carpet standard on April 16, 1971, and the children's sleepwear standard on July 30, 1971, the long-expected action by the government on the flammability of plastic materials has become factual. Soon, mandatory standards affecting flexible foams in such markets as bedding, drapery material, and the like, which are being studied by the Department of Commerce, will also be a reality. I n fact, the Department of Transportation has already issued Motor Vehicle Safety Standard No. 302 (MVSS 302) applicable to flammable interior materials in passenger vehicles, trucks, and buses and which is law as of September 1, 1972. Consequently, the foam industry is pursuing with vigor gearing to treat and test flammability of flexible foams. Use of fireretardant materials is expected to mushroom through 1975 with a predicted rate of growth of about 20%. Nonreactive Reagents. Phosphorus-Containing Derivatives. With few exceptions, additive reagents are used exclusively to commercially flame-retard flexible foams. The mainstays of this business are phosphate esters, most of which are presented in Table IX. Their inexpensive nature, high flame-retarding efficiency, and easy processability in foams are especially advantageous. A particularly desirable structural feature, which is common to all the reagents, is the presence of both phosphorus and halogen in rather high concentrations which contribute to their high effectiveness. The individual merits of chemicals falling in this category will be considered below. Tris(2-chloroethy1)phosphate and tris(2-chloropropy1)phosphate are made from the catalyzed reaction of ethylene and propylene oxide with phosphorus oxychloride, respectively (31, 90). Common effective catalysts are halides of titanium and zirconium (16). The product obtained by this method when propylene oxide is used in the reaction is usually a mixture of isomers including tris(2-chloropropy1)phosphate, t~ris(2-chloro-l-methylethyl)phosphate, and 2-chloropropyl and 2-chloro-1-methylethyl groups mixed on one phosphate ester. These compounds are exceptionally useful because of their solubility in a broad variety of reagents, thereby lending both to their frequent use as a coupling agent between slightly compatible components and in rigid foam systems where
Table IX. Some Commercial Nonreactive Flame Retardants for Flexible Foams Chemical name
p,
Structure
Tris (2-chloroethy1)phosphate
Tris(2-chloropropy1)phosphate Tris(2,3-dichloropropyl)phosphate Tris(2,3-dibromopropyl)phosphate Tris (1,3-dichloropropyl)phosphate
/
\
10 8
Table X. Slab Stock Foam Formulations and Foam Properties Containing Tris(2-Chloroethyl)Phosphate~
100
0 4.0
5 4.0
0.1 1.0 0.35
0.1 1.0 0.35
100 10 4.0 0.1 1.0 0.35
100 15 4.0 0.1 1.0 0.35
50.7 50.7 50.7 50.7 107 107 107 107 1.58 1.51 1.54 1.44 15.4 18.0 17.8 18.1 210 220 200 210 2.3 2.2 2.3 2.4 42 73 25
% 4.9 Resiliency, yo rebound 49 Air porosity, ft3/min/ft2 83 Humid aging, yo load loss, 5 hr a t 250°F 13.6 Flammability by ASThl D 1692-6iT Rating B Burning extent, in. ... Burning rate, in./min 6,5 a Taken from Reference 101.
Br,
%
68 7 491 27
35 2
[CHZOPO(OCH~CH~C~)~]Z
viscosity lowering is also desired. For maximum long-term storage stability, the phosphates should be incorporated into the isocyanate portion of formulations. They do not react with isocyanates (99). Also, the materials are moderately resistant to hydrolysis, probably because of their lack of solubility in water (especially the propyl derivative), and have proved satisfactory in applications involving moderate temperature and moisture conditions. However, because of their volatility, fogging can be a difficulty with concomitant loss in fire resistance of the base article. I n flexible foams many flame-retardant additives tend to cause foam scorch. With tris(2-chloroethy1)phosphate and
100
5 2 4 2
%
37 2 325 491
(CHzC1)z
C
Monsanto’s 2XC-20
CI,
8
(OCHzCHzC1)z 15
bfonsanto’s Phosgard C-22-R
NIAX Poly01 LG-56, parts Tris(2-chloroethy1)phosphate, parts Water, parts NIAX catalyst A-1, parts Silicone L-540, parts Stannous octoate, parts Toluene diisocyanate (80/20), parts T D I index Density, lb/ft3 Tensile strength, psi Elongation, yo Tear resistance, lb/in. 4-In. ILD, lb/50 25Y0 Deflection 65Y0 Deflection 25% Return 90% Compression set,
70
10 9 7 4 7
PO(OCHzCHzC1)3 PO [OCHzCH(CH3)C1]3 PO(OCH2CHC1CH2C1)3 PO(OCHzCHBrCH2Br)3 PO [OCH (CHzCl)2 1 3
37 67 25
37 66 24
34 63 22
5.6 49 77
5.7 49 84
5.2 50 85
14.4
18.8
18.6
B ... 4.0
SE 3.3 2.3
SE 2.1 1, 7
tris(2-chloropropyl)phosphate, this tendency is noticeably diminished (32, 100). Particularly in the case of the latter compound, this phenomenon is attributed to greater resistance to nucleophilic displacement of chloride ion (52). Generally, foams containing these products do not suffer much of a loss in properties, whereas only low concentrations of the additives produce vast improvement in fire-retardant characteristics. Their greatest drawback is being nonpermanent to dry heataging conditions of 14OOC for 22 hr (XSTM 01564-69). I n general, most suitable amounts of these materials are from about 5 to 15% on the weight of the polyurethane foam. Larger amounts may provide additional flame resistance but may also adversely affect physical properties. The data of Tables X and X I show typical formulations and physical properties for slab stock and molded flexible foams containing tris(2-chloroethyl) phosphate. *\nother equally important and popular additive is tris(2,3-dibromopropyl)phosphate. It can be prepared either by ~~
Table XI. Effect of Tris(2-Chloroethyl)Phosphate in Molding Flexible Formulation.
N A X Poly01 60-58, parts
Tris(2-chloroethyl)phosphate, parts
100 100 0 10 4.0 4.0 0.075 0.075 0.225 0.225 1.3 1.3 0.075 0.16 49.6 49.6 2.25 2.35 22.6 22.9 260 240 3.5 3.2
Water, part’s S I A X catalyst A-1, parts Dabco 33LV, parts Silicone L-540, parts Stannous octoate, parts Toluene diisocyanate (80/20), parts Density, lb/ft3 Tensile strength, psi Elongation, yo Tear resistance, lb/in. 13/4-In. ILD, lb/50 in.2 36 32 25y0 Deflection 87 80 65% Deflection 27 24 25y0 Return Compression set, 70 50% Deflection 6.0 9.4 90% Deflection 3.9 21.8 Flammability by ASThl D1692-67T Rating B SE ... 2.9 Burning extent, in. a Taken from Reference 102. LIolding conditions: type mold, aluminum; mold temperature at pour, 115°F; cure cycle, 5-min soak in hot mold and I-hr post cure at 250’F.
Ind. Enr. Chem. Prod. Res. Develop., Vol. 1 I . No. 4, 1972
385
Table XII. Phosgard C-22R in Slab-Stock Flexible Foam.
NIAX Poly01 LG-56, parts Phosgard C-22R, parts Water, parts NIAX catalyst -4-1, parts Silicone L-540, parts Stannous octoate, parts Toluene diisocyanate (80/20), parts T D I index Density, pcf Tensile strength, psi Elongation, % Tear resistance, lb/in. 4-In. ILD, lb/50 h 2 25% Deflection 65% Deflection 25% Return Resiliency, yo rebound 90% Compression set,
100 0 4 0.1 1.0 0,30
100 5 4
0.1 1.0 0,35
100 10 4 0.1 1.0 0.35
100 15 4 0.1 1.0 0.20
50.7 50.7 50.7 50.7 107 107 107 107 1.44 1.47 1.50 1.55 18.1 21.5 20.5 18.1 210 260 250 200 2.3 2.9 2.7 2.3 42 73 25 49
% 5 Air porosity, ft3/min/ft2 83 Humid aging, % load loss, 5 hr a t 250'F 14 Flammability by ASTM D1692-67T Rating B Burning extent, in. ... Burning rate, in./min 6.5 a Taken from Reference 101.
34 63 22 46
34 63 22 44
33 61 21 39
10 60
15 42
20 29
22
25
30
B ...
5.0
SE 2.7 3,2
SE 1.6 2.6
Table XIII. Reactive Flame-Retardant Reagents for Flexible Foam Name
Dibromoneopentyl glycol Trans-2,3-dibromo-2butene- 1,4-diol Brominex l60P Brominex 161P F R E-7067
OH no.
Br,
%
%
P,
...
428
61
456 47.0 66 23
. .. 65 36.0 2.5 24.0 2.3 17.6 8.0 (Cl, 17.8)
386
Ind. Eng. Chem. Prod. Res. Develop., Vol. 1 1 , No. 4, 1972
Dow GXF Swift Swift Stauffer
aldehyde (IS, 14). Of the additive types, this reagent has also reached significant importance in rigid as well as flexible foams. Typical data obtained in slab shock flexible formulations are given in Table XII. The results sholv that excellent flameretardant properties are procured, but the high phosphorus content causes thermal degradation of the polymer during aging tests. Use of this additive increases the possibility of foam scorch and gives softer foam with lower compression set's. Narrower and lowered tin operating range and longer gelation times, as compared to control foam, are also seen. Another more recent high-molecular-weight' product promoted as especially useful as a nonfugitive flame retardant' is Phosgard 2XC-20 ( 7 1 ) . This 2-chloroalkyl phosphate is readily prepared by treating the intermediate dichlorophosphate resulting from t'he reaction of neopentyl chloride and phosphorus oxychloride with ethylene oxide (15) Additionally, Fyrol 99 also has a phosphorus and chlorine base, and its high molecular weight makes it less volatile, giving longer lasting flame retardancy without appreciably reducing end-product properties (91). It is recommended for both rigid and flexible foams (91). .ilthough the structure has not been disclosed, a recently issued foreign patent may bear on its synthesis (105). Organohalides. There is evidence in the literature of \vork, primarily a t the development st'age, on strictly halogenated materials of high molecular Iyeight for use in flexible foams. Major emphasis appears to be on highly brominated derivaatives of benzene and polyphenyls such as hexabromobiphenyl (24)and hesabromobenzene (67). Several commercial products \yhich provide permanent effective flame retardance in flexible foams are believed to belong to this family of materials (58, 59). The effectiveness of aromatic bromides as flame retardants in flexible polyurethane foams has interesting mechanistic implications. Reactive Reagents. Because of several recent major and fatal fires in modern buildings, considerable study of the flammability problem by city authorities and insurers is being actively pursued. As a case in point, the Xeiy York Port Authority now requires all plastic furnishings to exhibit a flame-spread index not exceeding 100 by the XSTM E84 tunnel test or XSThl. E162-67 radiant panel test. The selfextinguishing property must also be an inherent part' of the properties of the material (80, 87). As a result of such action, other city authorities are following a similar course ( 1 ) . Consequently, a recent surge in search of highly efficient', durable reactive flame retardants has been initiated. IIajor industrial activity to date has been to develop phosphorus and/or bromine-containing polyols. However, for one reason or another, such as limit,ed processability-primarily narrow tin range, poor foam physical properties, foam scorching, odor, I
the addition of bromine to triallyl phosphate or by the reaction of 2,3-dibromopropanol with phosphorus oxychloride (25, 7 4 ) . I t s exceptionally high flame-retardant efficiency and 4% phosphorus and 69% bromine for a reasonable price are enticing features. Concentrations of about 5-10 wt yo in the polyurethane provide substantial flame resistance (18, 23). Surprisingly, unlike the 2-~hloroalkylphosphates, this compound does not suffer in permanency of self-extinguishing properties in time b u t does have limited utility where scorching is a problem. Minimal effects on physical properties are seen, although sometimes a tendency to increase compression sets is noted. The characteristic odor of bromine can be detected in foam bearing this derivative. Other available dihalo phosphates are the tris(dich1oropropy1)phosphates. These comprise a mixture of tris(2,3and 1,3-dichloropropyl)phosphatesprepared by the reaction of epichlorohydrin and phosphorus oxychloride. Because of high chlorine content, they are higher boiling and less soluble in water and, therefore, exhibit much less hydrolysis, as compared to the monochloro derivatives. However, about twice as much of this mixture is required to give comparable selfextinguishing properties to tris(2,3-dibromopropyl)phosphate, and flame-retardant properties tend not to be ret'ained after heat aging. Foam processing and physical properties are not affected. Increased permanency with nonreactive reagents has been achieved by the use of certain polymeric phosphorus derivatives. The earliest in this category to reach commercial significance was Phosgard C-22-R (70). The structure is given in Table IX. X colorless and odorless chlorine and phosphonate-bearing liquid, Phosgard C-22-R can be made by the reaction of phosphorus trichloride, ethylene oxide, and acet-
Source
~
and the like-the reactive flame-retardant approach has not been commercially successful to date. Several new reactive intermediates have evolved from research efforts in recent years. Most are shown in Table X I I I . The tabulation shows most reagents having a plurality of hydroxyl functionality and bound bromine in common. I n a few cases, phosphorus is also present. The first reactive candidates are being offered on a commercial scale under the Brominex trade name (93-95). Recent patents describe materials produced from the addition of elemental bromine to castor oil with subsequent introduction of phosphonate groups by means of an Arbuzov reaction with a trialkyl phosphite (55, 106-108). Analysis for elemental phosphorus and bromine and hydroxyl number determination affords average values from a multitude of possible products. Because bromine atoms of brominated castor oil are extremely labile, hydrogen bromide evolved during heating in the Arbuzov reaction may replace hydroxyl groups and generate carbon-bromine groups, thereby producing a product with lower hydroxyl number and a relatively stable C-Br bond. The products can be easily formulated in flexible foams without compromising the flexibility or resiliency of the base system and are recommended for use in automotive and aircraft industries (86). A new reactive diol containing 61% bromine was recently introduced by Dow Chemical Co. The new product, FR-1138 (36), replaced the former SA-1138 (37), dibromoneopentyl glycol, a polyester flame retardant which was not commercialized owing to high production costs (33).The most recent introduction is predominantly dibromoneopentyl glycol (>80y0) , with the remainder comprising primarily monobromoneopentyl triol and tribromoneopentyl alcohol (36). Unlike bypica1 halogen-containing flame retardants which contain either ordinary aliphatic or aromatic carbon-bromine bonds, this reagent possesses the unique features attributable to neopentyl systems. For example, it has excellent heat resistance and photochemical stability (54). Consequently, in addition to excellent flame retardancy and permanency, FR1138 is soluble in typical foam polyols and does not tend to cause scorching. -4significant increase in self-extinguishing properties can be obtained when FR-1138 is used in conjunction with phosphorus-containing polyols (82). Processing prove-out is underway. Another recent introduction which combines bromine and chlorine with phosphorus in a poly01 for permanent flame retardance is a product designated E-7067 (92). This material is self-extinguishing by ASTM D1692-67T which is retained after dry heat aging for 22 hr a t 140’C. Although the acid number is rather high a t 2.1 mg KOH/g (92) and is the cause for some difficulty in processing, this is not a major problem. Somewhat more serious is the odor imparted to foams. Cold Cure (High Resiliency). Aside from the foregoing, published reports do not indicate, as yet, other widely adopted commercial methods of flame-retarding flexible foams. However, prominent among approaches now under consideration are basic modifications in the foam chemistry. A promising approach which is receiving considerable attention is the new “cold cure or high resiliency” foams (60). Basically, this new technology provides flexible foams with a combination of properties unobtainable in conventional polyurethane or latex foams by use of highly reactive polyols with blends of T D I with specialty isocyanates of high functionality such as M D I and T D I residue products (82, 83). Besides attractive properties such as high resiliency, good load ratio, low hysteresis loss, and latex feel, usefulness resides in their
Table XIV. Sample Formulation and Properties of Molded Cold Cure Foam.
NIAX Poly01 11-27 70 XIAX Poly01 3 4 2 8 30 2 7 Water Solid dabco 0 1 KIAX catalyst -4-1 0 06 0 8 AT-Ethyl morpholine Dibutyl tin dilaurate 0 03 Silicone Y-6550 1 0 Isocyanates T D I (80/20)/NIXX AFPI (80/20 ratio, 44.9% free S C O ) 34 3 Index 105 Density (core), pcf 2 4 60 Resilience, % ball rebound ILD, lb/50 ine2 25yc Deflection 24 0 65% Deflection 64 9 Return value, % 81 0 Load ratio 2 7 14 4 Compression set, 75yC, yo Tensile strength, psi 26 0 Elongation, yo 230 Tear resistance, lb/in. 2 90 14 3 5-Hr humid aged load loss, yo 26.9 50% Humid aged compression sets, yo Flammability, by MVSS 302 SE* a Taken from Reference 103. Molding conditions involved an Admiral machine (25 lb/min) with two component streams at 7 5 4 0 ° F and an aluminum mold a t 130°F with 8-min demolding time. b Did not burn beyond the first bench mark.
inherent flame resistance. This provides an alternate route to the use of reactive flame-retardant reagents in conventional hot cure foam to classify as self-extinguishing. Although the high functionality of the isocyanates might be expected to increase the heat resistance of the foams ( 7 7 ) ,it is puzzling to ascertain the requirement of only certain ratios of T D I to polymeric isocyanate for maximum thermal stability and fire resistance (82, 85).Nevertheless, foams made by this process easily pass MVSS 302 and ASTM D1692-67T. h typical formulation and properties of a cold cure foam are listed in Table XIV. =inother significant characteristic of cold cure foam is the low smoke generated during combustion. Post Treatment of Foams. Still another recently developed approach involves post treatment of flexible foams with various inorganic flame-retardant compounds in the presence of binding agents (82, 83). Flame retardants such as MgNH4PO4 and CaNH4P04 with polyvinyl acetate binder are used as impregnants. The process is ordinarily carried out by soaking the foams in an aqueous suspension of the ingredients and drying. The effect is said to give excellent flame retardancy which is permanent with only slight effect on physical properties. However, loadings of 70-130yc are required. Polyester-Urethane Foams
The foregoing discussion was concerned only with flameretarding polyether-urethane foams. Large markets also exist for flame-retarded polyester-urethane foams, for example, as rug and drapery backing material. Because of the differences in end-use, the problems associated with permanently flame-retarding flexible polyether vs. polyesterurethanes are varied. For example, polyester-based urethanes are expected to maintain flame-retardant characteristics through laundering and dry cleaning procedures. When the articles are subjected to alkali, such as laundering with deInd. Eng. Chem. Prod. Res. Develop., Vol. l l , No. A , 1972
387
tergents, it is doubtful that brominated flame retardants will survive. This will pose severe limitations on the types of effective materials. Recently, the availability of a polyesterurethane foam capable of passing ASTM D1692-671‘ and UL-94 under the trade name of Pyre11 was announced (89). Acknowledgment
The author extends special acknowledgment to W. R. Proops of Isocyanate Products Division of Witco Corp. and P. E. Burgess, Jr., of Panacon Corp. for invaluable discussions which led to the foregoing review. literature Cited ( I ) Abbott, J . C., Fire J., 88 (July 1971). (2) Anderson, J. J., Camacho, V. G. (to Mobil Oil Corp.), U S .
Patent 3,565,812 (February 23, 1971). (3) Anderson, J. J. (to Mobil Oil Corp.), British Patent 1,094,489 (December 13, 1967). (4) Ashida. K.. Petrol. Petrochem.. 13 (9). 84 (1969). ( 5 ) Arvidson, 8. C., Blake, N. (to E. ’I. du Pont de Nemours & Co.), U.S. Patent 2,999,839 (September 12, 1961). (6) ASTM Method D2863-70, Book ASTM Stand., 27, 719 \( -i ”~.7 -,.n )
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(10) Belgium Patent 705,441 (to Lankro Chemicals) (October 21, 1966). (11) Belgium Patent 742,564 (to Dow Chemical Co.) (December 4, 1968) (U.S. Appl. 781,261/68). (12) Belgium Patent 742,565 (to Dow Chemical Co.) (December 4, 1968) (U.S. Appl. 781,261/68). (13) Birum, G. H. (to Monsanto Chemical Co.), U.S. Patent 3,014,956 (December 26, 1961). (14) Birum, G. H. (to Monsanto Chemical Co.), U.S. Patent 3,042,701 (July 3, 1962). (15) Birum, G. H. (to Monsanto Chemical Co.), U.S. Patent 3,192,242 (July 29, 1965). (16) British Patent 701,794 (to Union Carbide Corp.) (January 6, 1954). (17) British Patent 954,792 (to Virginia-Carolina Chemical Corp.) (April 8, 1964). ’ (18) British Patent 964,266 (to Union Carbide Corp.) (July 22, 1964). (19) Biitish Patent 999,588 (to Virginia-Carolina Chemical Corp.) (July 28, 1965). (20) British ‘Patent 1,002,272 (to Jefferson Chemical Co.) (August 25, 1965). (21) British Patent 1.147.941 (to Standard Oil Co.), (April 10, ’ 1969). (22) Camacho. V. G.. Anderson. J. J.. Bvrd. W. M. (to Mobil ‘ Oil Corp.), U.S. Patent 3,465,068 (Septcmber 2, 1969). (23) Carroll, W. G., Crook, J. W., Harris, G. A. (to Im erial Chemical Industries), British Patent 1,226,757 (Marc1 31, I
,
1071) * ” . -,.
(24) Chem. Eng. News, 49 (20), 1 (May 17,1971). (25) Chem. Week, 69-72 (December 1969). (26) Chem. Week, “Rigid Urethane Builds a Growth Market” (December 3, 1966). (27) Chem. Process, 33 (5), 55 (1970). (28) Cox, E. F., Cook, W. H., Hostettler, F. (to Union Carbide Corp.), U.S. Patent 3,186,969 (June 1, 1965). (29) Cox, E. F., Cook, W. H., Hostettler, F. (to Union Carbide Corp.), U.S. Patent 3,245,924 (April 12, 1966). (30) Cox, E. F., Knopf, R. J. (to Union Carbide Corp.), U.S. Patent 3,436,373 (April 1, 1969). (31) Crook, J. W., Haggis, G. A. (to Imperial Chemical Industries, Ltd.), British Patent 1,168,544 (July 16, 1969). (32) Crook, J. W., Haggis, G. A., J . Cell. Plast., 5, 119 (1969). (33) “Daily News Record,” p 3, Fairchild Publications, New York, N.Y., Tuesday, October 5, 1971. (34) Davis, B. D., Jones, E. E., Morgan, R. E. (to Dow Chemical Co.), U.S. Patent 3,598,771 (August 10, 1971). (35) Delman, A. D., J . Macromol. Sci., Rev. Macromol. Chem., 3 (2), 281 (1969). (36) Dow Chemical Co., Technical Bulletin, FR-1138, September 10, 1971. (37) Dow Chemical Co., Technical Bulletin, SA-1138 Dibromoneopentyl Glycol. (38) Edwards, G. D., Rice, D. >I., Soulen, R. L. (to Jefferson Chemical Co.), U.S. Patent 3,297,597 (January 10, 1967). 388
Ind. Eng. Chern. Prod. Res. Develop., Vol. 1 1 , No. 4, 1972
(39) Fenimore, C. P., Martin, F. J., Combust. Flame, 10 (2), 135 (1966). (40) Frey, H. E. (to Standard Oil Co.), U.S. Patent 3,300,420 (January 24, 1967). (41) Friedman, L. (to Weston Chemical Corp.), U.S. Patent 3.009.939 (November 21. 1961). (42) Friedman, L. (to WeBton Chemical Corp.), U.S. Patent 3,081,331 (March 12, 1963). (43) Friedman, L. (to Weston Chemical Corp.), U S . Patent 3,092,651 (June 4, 1963). (44) Friedman. L. (to Union Carbide CorD.,), U.S. Patent 3,139,450 (June30.‘19&). (45) Fhedman‘, L. (to Union Carbide Corp.), U.S. Patent 3,261,814 (July 19, 1966). (46) Frisch, K. C., Patel, K. J., Marsh, R. D., J . Cell. Plast., 6,203 (1970). (47) Hilado, C. J., Burgess, P. E., Proops, W. R., ibid., 4, 67 (1968). (48) Hilado, C. J., Patten, W., ibid., 7,3 (1971). (49) J . Cell. Plast., 3, 13 (1967). (50) Ibid., “Cellular Plastics Industry News,” 3, 13 (January 1967). (51) Zbid., 4 (lo), 369 (1968). (52) Ibid., 5 , 16 (1969). (53) Lanham, W. M. (to Union Carbide Corp.), U.S. Patent 3,099,676 (July 30, 1963). (54) Larsen, E. R., 158th ACS National Meeting, Prepr. 375, New York, N.Y., 1969. (55) Lewis, M. (to Swift and Co.), U.S. Patent 3,534,073 (October 13. 1970). (56j Lewii, Jr.,-W. W., Pizzini, L. C. (to Wyandotte Chemicals Corp.), U.S. Patent 3,585,185 (June 15, 1971). (57) Michigan Chemical Corp., Technical Data, “Firemaster HBB,” May 1971. (58) Michigan Chemical Corp., Technical Data, “Firemaster FF-1 ” May 1971. (59) Michigan Chemical Corp., Technical Data, “Firemaster FF-2.” Mav 1971. (60) Mod. Pllst., 48 (6), 44 (1971). (61) Zbid., 47 (ll),68 (1970). (62) Zbid. (10). 68 (1970). (63) Ibid. (3),’26 (1970).’ (641 Ibid.. 46 (9). 94 (1969).
gard C-22-R Flame Retardant,” Form 10635-1. (71) LMonsanto Chemical Co;: Technical Data Sheet “Phosgard 2XC-20 Flame Retardant, March 1970. (72) Naturman, L. J., S P E J . , 965 (1961). (73) Odinsk, A., Re more, Jr., H. E., Sayigh, A. A. R. (to Upjohn Co.), U.S. Satent 3,499,009 (March 3, 1970). (74) Overbeck, D. E., Nametz, R. C. (to Michigan Chemical Corp.), U.S. Patent 3,046,297 (July 24, 1962). (75) Papa, A. J., Ind. Eng. Chem. Prod. Res. Develop., 9 (4), 478 (1970). (76) Papa, A. J., unpublished results, Union Carbide Corp., S. Charleston, W.Va., 1971. (77) Parrish, D. B., Pruitt, R. M., J . Cell. Plast., 5 (6), 348 (1969). (78) Patton, J. T., Austin, R. J. (to Wyandotte Chemicals Corp.), U.S. Patent 3,350,389 (October 31, 1967). (79) Pelletier, P. E., Pelletier, F. (to Wyandotte Chemicals Corp.), U.S. Patent 3,402,132 (September 17, 1968). (80) Port of New York Authority, “Specifications Governing the Flammability of Upholstery Materials and Plastic Furniture,” Inspection and Safety Division, Operations Services Department, October 1970. (81) PPG Industries Information Bulletin, “Selectrofoam 644365058, ‘l?yo-Component, Fire-Retardant Rigid Urethane Foam System, August 24, 1970. (82) Pruitt, R. M., “Self-Extinguishing Characteristics of FlameResistant Flexible Urethane Foams,” SPI Meeting, Automotive Section, Detroit, Mich., February 24, 1970. (83) Pruitt, R. M., J . Cell. Plast., 6 (6), 262 (1970). (84) Robitschek, P., ibid., 1,395 (1965). (85) Rosenberg, R. H., Cooper, R. S. (to Stauffer Chemical Co.), U.S. Patent 3,294,710 (December 27, 1966). (86) Rubber Age, 102, 88 (August 1970). (87) Rubber Plast. News, 1 (3), 6 (September 13, 1971). (88) Schmidt, W. G., Trans. J . Plast. Inst., 33 (log), 247 (1965). (89) Scott Paper Co. Technical Information Bulletln, Form No. 3665, “Scott Pyfell Foam, A Fire Retardant, Flexible Polyurethane Foam, 1970. (90) Smith, A. L. ( t o Celanese Corp. of America), U.S. Patent 3,100,220 (August 6, 1963). ~
(91) Stauffer Chemical Co., Application Data, “Fyrol 99, Fire Retardant, Use of Fyrol99 in Urethane Foams,” 1971. (92) Stauff er Chemical Co., Technical Bulletin, “Preliminary Data Sheet. Flame Retardant E-7067. A New Reactive Flame Retardant Containing Chlorine, Bromine and Phosphorus,” July 31, 1970. (93) Swift Chemical Co., Technical Bulletins, “Brominex 9113, 9115, and 9117” Nos. 727, 728, and 729, May 1969. (94) Swift Chemical Co., Technical Bulletin, “Brominex 16OP” No. 737, February 1971. (95) Swift Chemical Co., Technical Bulletin, “Brominex 161P” No. 738. Februarv 1971. (96) Theupjohn do., CPR Division Bulletin 8a/Cp, “Urethane Insulation,” Form No. CPR SWT K9. (97) The UDiohn Co.. CPR Division Bulletin, “CPR 421,” De~ember~l”970. (98) Unarco Industries, Inc., Chembest Division, “Unarco Rigid Urethane Foam Data,” October 1, 1967. (99) Union Carbide Corp. Product Information Bulletin, “NIAX Flame Retardant 3CF for Urethane Use, No. F-42625, 10/69-8M. (100) Union Carbide Corp. Technical Service Report, “NIAX Flame Retardant 3CF,” No. F-677. ~
(101) .Union Carbide Corp. Technical Service Report, “Comparison of Three Flame Retardant Additives,” No. F-693. (102) Union Carbide Corp. Technical Service Report, “NIAX Flame Retardant 3CF Addition to a Flexible Molding Formulation,” No. F-698. (103) Union Carbide Corp. Technical Service Bulletin, Research and Developme,$ Department, “Highly Resilient Molded Urethane Foam. (104) Walsh, E. N., Uhig, E. H., Beck, T. M., Division of Organic Coatings and Plastics, ACS, Prepr., 23 (I), 1 (1963). (105) Weil, E. D. (to Stauffer Chemical Co.), West German Patent 1,947,224 (June 4, 1970). (106) West German Patent 2,045,428 (to Swift and Co.) (May 27, 1971). (107) West German Patent 2,046,073 (to Swift and Co.) (Februar 18,1971). (108) est German Patent 2,046,074 (to Swift and Co.) (February 2, 1971). (109) Wyandotte Chemicals Corp. Technical Bulletin U-07R, “Pluracol 601 Spray S stem for Rigid Urethane Foams with UL Rated 25-Or-Less Frame Spread,” September 11, 1970. RECEIVED for review April 14, 1972 ACCEPTED July 18, 1972
6’
Catalytic Disproportionation of 1-Octene Akira Uchida,’ Kiyotaka Kobayashi, and Sumio Matsuda Department of Petroleum Chemistry, Faculty of Engineering, Osaka University, Yamadakami, Suita, 565, Japan
1 -0ctene was treated with Et3AI-WCIa in degassed chlorobenzene. No reaction products were detected in the reaction mixture immediately after mixing of the reagents. After one day, however, ethylene, tetradecene, and alkanes were found in the reaction mixture. 1-Octene treated with EtSAI-WCIG in chlorobenzene containing dissolved oxygen quickly gave olefins ranging from ethylene to tetradecene and alkanes. In both cases, no alkyl chlorobenzene was detected in the reaction products. The formation of two types of active species was proposed. In the absence of oxygen, one caused disproportionation of 1 octene without migration of the double bond, and the other caused oligomerization of the olefin. In the presence of oxygen, one caused migration of the double bond followed by disproportionation to various olefins, and the other caused oligomerization of the olefin. With the same catalyst in degassed benzene, alkanes were formed, but no alkylbenzene could be detected. Thus, formation of a Friedel-Crafts catalyst in this system probably does not occur. However, alkylbenzenes were formed by addition of water or oxygen to this system.
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T h e catalyst system composed of triethyl aluminum (Et3A1)tungsten hexachloride (WClG)-benzene (or toluene) is active for the disproportionation of 2-pentene and has lower activity as a Friedel-Crafts catalyst than monoethyl aluminum dichloride-WC18-benzene (or toluene). Attempts to disproTOwhom correspondence should be addressed.
portionate a-olefins with t h e former catalyst system failed except in a special case, and the reaction products were usually oligomers of olefins, alkylates of solvents, or a mixture of both (Uchida e t al., 1971b). The system WClo-Et,Al-benzene was inactive for the disproportionation of a-olefins, but addition of oxygen to Ind. Eng. Chem. Prod. Res. Develop., Vol. 1 1 , No. 4, 1972
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