CA1317603C - Flame retardant higher alkyl bisphenoxy alkanes and their application to abs polymer systems - Google Patents

Abstract

ABSTRACT
Halogenated unsymmetrical higher alkyl bisphenoxy alkanes have utility as non-blooming flame retardant agents. In particular, halogenated unsymmetrical higher alkyl bisphenoxy alkanes along with an enhancing agent may be used to render an ABS
resin flame retardant.

Description

1317~3 FLAME RETARDANT ABS RESIN COMPOSITION
AND ITS APPLICATION TO ABS POLYMER SYSTEMS

BACKGROUND OF THE INVENTION
Field Of The Invention. The present invention relates t~ a plastic additive composition and more particularly to a plastic additive composition comprising halogenated unsymmetrical higher alkyl bisphenoxy alkanes. In addition, this invention relates to a nonblooming flame retardant ABS resin composition incorporating the halogenated unsymmetrical higher bisphenoxy alkanes.
Description Of The Prior Art. Traditionally, plastic additive compositions are an important class of industrial materials. Plastic additives are used to enhance or modify the properties of commercially avail-able polymers. The use of plastic additives allows a ::
relatively small number of commercially available polymers to b tailored to a myriad of uses. Those killed in the art will know that~the selection of an application of a specific pl~astic~additive is unpre-dictable at best. Therefore, additive manufacturers must take a sophistlcated approach~and offer a range of products to achieve the desired~result.
Plastic additive compositions can be used as plasticizers, flame retardants, flow modifiers, or impact modifiers in resin systems, heat transfer fluids, or hydraulic fluids.

::

~3~7~3 One important use of plastic additive compositions is as flame retardant agents in resin systems. Mo~t flam~ retardant agents, although efficient in their function of retarding the rate of combustion in a resin system, have a tendency to affect adversely one or more key properties of the resin. Eor example, many flame retardant additives tend to reduce the impact strength of the resin; to migrate from the resin composition, resulting in a phenomena known as "bloom"; to volatilize from the resin composition; to plasticize the resin composition adversely, and therefore lower the heat deflection temperature; or to degrade when exposad to indoor or outdoor light.
It is, therefore, essential that flame retardant agents be specifically tailored to the resin system so that in addition to their role as flame retardants, they will also enhance the desirable characteristics of the resin composition. Those skilled in the art well know that the selection of such an application specific 20 ~ flame retardant is unpredictable at best. Moreover, even if a given agant may exhibit utility in a partic-ular resin æystem, there is no guarantee that this ; agent will have;any use at all with other resins. One ; ~ type of resin used in the formulation of a flame retardant is acrylonitrile-butadiene-styrene ("ABS") resin. Some of the properties of typical ABS resins :; : :

::

~ 3 ~ 3 are described on pages 1-68 of Harper's Handbook of Plastics and Elastomers published by McGraw-Hill Book Company in 1975.
ABS thermoplastics offer a good balance of physical and mechanical properties such as good abuse resistance, heat resistance, moldability, stain resistance, chemical resistance and surface hardness.
Typically, ABS thermoplastics are used in a wide variety of applications because of their properties and moderate costs. For example, ABS thermoplastics are used by telephone equipment, electronic, and automotive manufacturers who require materials of high impact strength.
A number of flame retardants have been described or ABS re~ins in the art. For example, the following materials have all been used in various ABS systems:
bis(tribromophenoxy)-ethane, bis(pentabromophenoxy)-ethane, octabromodiphenyl oxide, decabromodiphenyl oxideJ tetrabromobisphenol-A, bis(tribromophenoxy-ethyl)-tetra bromobisphenol A ether. Among the prîor art specifically dealing with flame retarding ABS
resins are U.S. Patent No. 4,016,139; and U.S. Patent No. 4,567,218, and the references cited therein. The --foregoing flame retardant agents for ABS plastics have not been entirely satisfactory because of problems of bloom, thermal migration? heat instabilityJ ultraviolet 11 3 ~

light instability, discoloration, or adverse effects on properties such as impact str~ngth and flowability.
Many applications of ABS resins with flame retardant agents reguire that certain key properties be maintained. Examples of key properties include impact strength, light stability and retention of surface aesthetic properties. In particular, manufacturers of computer housings desire a thermoplastic ABS resin which is ~lame retardant, light stable, and resistant to bloom.
It is well known in the art to use various bromine containing compounds as flame retardant agents. The compositions obtained using these various bromine containing compounds have a tendency to change color on expo~ure to light, to develop a reduction in surface gloss, and to form deposits of flame retardant agents on the polymer surface.
Anderson, et al , U.S. Patent No. 3,876,612 disclo6e ABS plastic~compositlons containing s~ymmetrical bi phenoxy flame retardants. The compo~ition of the flame~retardants are depicted by the~following formula: ~ ~

~ ;
Zm ~ O-R-O~ ~Zm ~

' ~ :
:

13~ 7~

where Z is bromine or chlorine; m and m' are integers having a value of 1-5; and i and i' are integers having a value of 0-2; A is a cyano, nitro, lower alkoxy, lower alkyl, fluorine, dialkylamino, phenyl, halo-phenyl, benzyl or halo-benzyl group; and R is chosen from the following group:

t~) CN2- SH(OH) 5U2 ~b) e~2- ~(~20N)-~) (CH2)W- O - (CR2)w ~here w - 1-6 ~2 uh~ro X~H, Cl,~r ) CH2 C(O)_ C~2 n~4 ~) CH2- CH

~ ,.
~ N2 bh~e S - e~r eed : : 20 Anderson, et al., '612 does not disclose the use : of an unsymmetrical higher alkyl bisphenoxy alkane as a flame retardant~agent for the disclosed ABS resin.

: U.5. Patent No. 3J883J479 issued to Anderson, et al., discloses pla9tic compositions containing ABS and 25~ symmetrical bisphenoxy compounds. The bisphenoxy : compounds have the formula-~: :
: ~ :

Ai 2 ~ 0 _ (alk~lene) _ 0 ~ ~Zm~

wherein Z is bromine, m and m' are integers having a valua of 1-4, i and i' are integers having a value of 1 or 2. The alkylene is a straight or branched chain alkylene group having from 1 to 6 carbon atoms. A is to be selected from the group consisting of cyano, nitro, lower alkoxy, lower alkyl (defined as CH3J C2H5, C3H7 or C4Hg), fluorine, dialkylamino, phenyl, halo-phenyl, benzyl or halo-benzyl group. Anderson, et al., '479, do not dlsclose the use of an unsymmetrical higher alkyl bisphenoxy alkane as a flame retardant agent.
Anderson, et al., U.S. Patent No. 3,892,710 disclose ABS plastic composltions~containing 20~symmetrical halogenated~alkyl flame retardants. The flame~retardants hav~ the formula:

Zm ~ M _ R; ~ - M' ~ ~n' :~: :

13~7~

where Z is bromine or chlorine; m and m' are integers having a value of 1-5, i and i' are integers having a value of 0 to 2, M and M' are each independent and are from the group consisting of oxygen, nitrogen or sulfur as long as both m and m' are not oxygen. A is chosen from the group consisting of cyano1 nitro, lower alkoxy, lower alkyl, fluorine, diakylamino, phenyl, halo-phenyl, benzyl or halo-benzyl group. Anderson, et al., '710's disclosure on halogenated aryl flame retardants fails to suggest usage of an unsymmetrical higher alkyl bisphenoxy alkane.
In U.S. Patent No. 3,971,758, Anderson, et al., disclose an ABS plastic composition containing symmetrical bisphenoxy flame retardant compounds. The compositions of the flame retardants have the formula:

2~ ~ 0--(N~C~ Zm~

:
~
where Z is bromine or chlorine; m and m' are integers having a vaIue of 1 to 5; i and i' are integers having a value of 0 to 2; HBCA is~a halo-branched alkylene group having from 1 to 6 carbon atoms; and A i~s cyano, nitro, lower alkoxy, lower alkyl (Cl-C4)j fluorine, :
; dialkylamino, phenyl, halo-phenyl, benzyl or ~ halo-benzyl group. Again, Anderson, et al., '758 fail :

1 3 ~

to disclose usage of an un6ymmetrical higher alkyl bisphenoxy alkane as a flame retardant agent.
Anderson, et al., U.S. Patent No. 4,016,137, describe plastic compositions containing ABS and symmetrical bisphenoxy flame retardant compounds, which have the following formula:

~_0- (alkyleAe)-O-~mt where Z is bromine, m and m' are integers having a value between 1 and 5 and the alkylene is a straight or branched alkylene group containing 1 to 6 carbon atoms.
This reference again fails to suggest usage of an unsymmetrical higher alkyI bisphenoxy alkane as a flame ~retardant.
~ Anderson, et al., U.S. Patent No. 4,016,139 disclose a composition containing an ABS polymer, a symmetrical bisphenoxy flame~retardant and a flame retardant enhancing agent. The bisphenoxy flame retardant has the following formula:

Zm~ O T --O ~-Zm~

wherein Z is bromine, m and m' are integers having a value of 1 to 5 so that the total bromine atom content ranges from 6 to 10 atoms, and T is a straight chain or branched chain carbon group having 1 to 4 carbon atoms.
S There 1S a lack of disclosure of an unsymmetrical higher alkyl bisphenoxy alkane compound in Anderson, et al., '139.
Anderson, et al., U.S. Patent No. 4,051,105, disclose a plastic composition. The pla~tic composition contains an ABS polymer and a symmetrical bisphenoxy compound having the formula:

Zm~ o~ lkylene~-O~ Zm' where Z is bromlne, m l~S an integer having~a value of 1 0 ; to 5, and m'~is an~integer~having a value of O to 4, i i an integer~having a;value of 0 to 2,~and i' is an -integer having a value of 1 to 5. The alkylene is a straight or branched chain alkylene group having from 1 to 6 carbon atoms and A is chlorine. Clearly there is 25 ~ no di~closure of unsymmetrical higher alkyl bisphenoxy compound in Anderson, et al, '105.
In overview, the bromine containing compounds for ABS resins described by the Anderson, et al., patent-~

::

~3~7~

disclose the usage of symmetrical bisphenoxy alkanecompounds containing nuclear aromatic bromination, alkylation and various other substitutions. The use of these symmetrical bisphenoxy alkane compounds has not been entirely satisfactory in~ the ABS systems. In particular, the symmetrical bisphenoxy compounds such as bis(tribromophenoxy)-ethane tend to bloom or migrate to the polymer surface in ABS systems.
Accordingly, a primary object of this invention is to provide new unsymmetrical higher alkyl halogenated ~bisphenoxy alkanes.
Another object of the invention is to provide halogenated unsymmetrical higher alkyl bisphenoxy alkanes having utility as flame retardant agents.
Yet another object of the invention is to provide halogenated unsymmetrical higher alkyl bisphenoxy alkanes having utility as non-blooming flame retardants.
An additional object of the present invention is to provide an agent capable of flame retarding ABS
resin~compositlons without exhlblting problems of bloom, heat or light instnbllity~or any of the other di advantages of the prior art ABS flame retardant agents.
A further object is to provide flame retardant ABS
res1n compositions that exhibit the desired level of flame retardancy without suffering any deterioration of physical properties.

13:~7~

Yet a furthar object is to utilize halogenatad unsymmetrical higher alkyl bisphenoxy alkane as flame reta dall'c ~gents for ABS resins.
SUMMARY OF THE INVENTION
The foregoing and other objects, advantages and features of this invention may be achieved with new compositions of matter comprising halogenated unsymmetrical higher alkyl bisphenoxy alkanes.
Preferably the bisphenoxy alkane used in accordance with this invention is a brominated unsymmetrical higher alkyI bisphenoxy ethane. The preferred brominated bisphenoxy ethane contains between 40 and 70 percent by weight of bromine. In addition, the invention contemplates incorporating an effective amount of halogenated unsymmetrical higher alkyl bisphenoxy alkane and an enhancing agent into a normally combustible ABS resln to obtain a flame retardant ABS resin composition. The compositions of this invention pre~erably comprise about 50 to 90 percent ABS thermoplastic resin,~about 5 to 30 percent halogenated unsymmetrical~higher alkyl bisphenoxy alkane and about 0.1 to 15 percent enhanciny agent, all by weight of the composition.
DETAILED DESCRIPTION OF THE INVENTION
In accordance w1th this invention, new halogenated unsymmetrical higher alkyl bisphenoxy compounds have been discovered. ~The novel compositions of this invention are distinguished from the known bisphenoxy 1 3 ~

compositions by improved properties. The novel compositions are stab e to light and heat, have good flame retardant properties, and, most importantly, compositions incorporating the novel compounds do not bloom.
The novel compositions of matter are halogenated unsymmetrical higher alkyl bisphenoxy alkanes of the following formula:
~ 2 ~ -O- (R3 ) -0- ~

Xz X
y wherein X i8 bromine or chlorine; z is an integer from 2 to 4; R1 is an alkyl ranging from methyl (CH3) to dodecyl (C12H25); n is O, 1, or 2; y is O, 1, or 2; R2 is an alkyl selected from the group consisting of sec-butyl, (sec C4Hg), pentyl (C5H1l) hexyl (C6H133, ZO ~heptyl (C7Hl5), octyl (C8H17), Y g 19 (ClOH2l), undecyl (C~1H23)~and dodecyl (C12H25). R is a~straight or br~anched alkylene group from methyl ~CH3 to dodecyl (C12H25) such as cyclohexane or example;
and if n is 1, R1 is not R2. The novel composition of matter contains some minor amounts of symmetrical halogenated higher alkyl bisphenoxy alkanes. The minor amount0 in the composition do not effect the utility of the composition as a non-blooming flame retardant :::
~ agent.

~:

1~ 7~

When X is bromine, the bromine content should be between approximately 40 percent and 70 percent by weight. Especially preferred bisphenoxy compounds, for example, are those compounds where x is 3, z is 2, and n is zero. In these most praferred compounds X is bromine, R2 is either octyl (C8H17) or nonyl (CgH19) and R3 is ethylene.
The preferred novel plastic additive compositions, brominated bisphenoxy ethanes are prepared in a two-step synthesis from brominated phenols and dihalogenated ethanes. The synthesis follows standard Williamson ether synthesis techniques, shown below without substitution:

C ~ 0H + NaOH ~ ~ -O Nat+ ~20 ~O ~ O Na+ + X-C~2CH~-Y _ > ~ -O-C~2CH2Y+NaX

N +~ O-CH2CH2Y --~

~ o-CH2-CH2 ~ +NaY
.

wherein X and Y are independently bromine or chlorine.
The preferred method of synthesis is to react the phenate salt containing the least alkyl content with a large excess of 1,2-dibxomoethane (24 moles/mole phenate) in a polar, high-boiling solvent such as propylene glycol. The excess dibromoethane is then preferably removed by distillation before reacting the intermediate with the second phenate salt.
The compounds lieted in Table 1 are examples of compounds synthesized by the preferred synthesis method. The list is not intended to be exhaustive or to limit the scope of the invention. The brominated alkyl phenols were produced from commercially available alkyl phenols using techniques known in the art.
Table 1 TGA, C % 8r C~eY~ _ Z Y _~ n~ 5~ Z5;~ 50i~ Theory Found A 3 2 -- 0 C9H19 ~ 315 365 389 54.4 54.1 20 ~ 2 " C8H~7 302; 353 ~ 376 55.4 55.5 :
C~ " 2 -- ~ C5H11 ~ 309 35~ 382 5A.9 58.7 D ~ ~ 2 __ C12H25 336 386 408 51.4 51.3 E~' 2 CH3 2 ~ CnC17 315 358 379 53.3 53.8 G 4 2 CN3 1 C9H~9 3Z8 382 4n8 57.9 57.6 2 5 N 4 2 CH3 I C12H25 363 411 4Z9 55.1 55.1 I 5 Z -- 0 C9H~g 361 409 426 62.6 62.0 ~ 3 2 -- 0 Sec 313 363 387 60 59.5 :: C ~7 ~::: 4 9 :;

13~7~J

The halogenated unsymmetrical higher alkyl bisphenoxy alkanes can be used individually or in conjunction with other additives in plastics formulations. When the preferred brominated bisphenoxy ethane is used in a plastic formulation, it should be employed in amounts of 0.5 to 30 percent by weight of plastic ~ormulation. The most preferred weight percent of brominated bisphenoxy ethane in the plastic formulation is 5 percent to 20 percent.
This invention also encompasses use of unsymmetrical bisphenoxy compounds in an ABS resin.
Halogenated unsymmetrical higher alkyl bisphenoxy alkanes are useful in the preparation of non-blooming flame retardant ABS resins. The novel compositions of this invention are d1stinguished from known f].ame retardant ABS compositions by improved properties.~
Preferred novel flame retardant ABS
compositions may be prepared by admixing from aboùt 50%~to about 90%~by weight~thermoplastlc ABS resin;
from ab~out 5% to~about 30% by~we1ght halogented unsymmetrical higher alkyl bisphenoxy alkane com-pounds; from about 0.1% to about 15% by weight ;~ 25 enhsncing agent, where the percentages are based on the total weight of the resulting admixture of these three components. Most desirably, the compositions of this invention comprise about 60 to 90% ABS
~: :

~::
.

13~ ~J~

resin; about 10 to 30% halogenated unsymmetrical higher alkyl bisphenoxy alkane compound; and about 2 to 10% enhancing agent.
The ABS resin may be any thermoplastic resin formed by blending a styrene/acrylonitrile copolymer with butadiene-based rubber, or by grafting butadiene-based rubber with styrene/acrylonitrile chains; or by copolymerizing styrene, acrylonitrile and butadiene monomers. Thus, substantially any ~uitable acrylonitrils-butadiene-styrene composition may be used, containing each component of the terpolymer in substantially any proportion. The ABS
may contain or may be substantially free of other additives such as stabilizers, plasticizers, dyes, pigments, fillers and the like.
The preferred plastic composition additives in the preparation of non-blooming flame retardant ABS
resins are all unsymmetrical, that is Rl is not R~
where n is 1. The preferred additives in accordance with this invention include:
l-(tribromophenoxy)-2-(dlbromononylphenoxy)-ethane;
l-(tribromophenoxy)-2-(dibromooctylphenoxy)-ethane;
: l-(tribromophenoxy)-2-(dibromopentylphenoxy)-ethane;
l-(trlbromophenoxy)-2-(dibromododecylphenoxy)-ethane;
1-(tetrabromomethyIphenoxy)-2-(dibromooctylphenoxy)-ethane;
l-(tetrabromomethylphenoxy)-2-(dlbromononylphenoxy)-ethane; or l-(pentabromophenoxy)-2-(dibromononylphenoxy)-ethane.

~ 3~ 7~

The ABS flame retardant compositions of this invention also desirably incorporate one or more enhancing agents. Enhancing agents useful in accordance with this invention comprise the oxides and halides of groups IV-A and V-A of the periodic table; organic or inorganlc compounds of phosphorous, nitrogen, boron or sulfur; and oxides and halides of, for example, zinc, magnesium and titanium, all as disclosed in U.S. Patent No. 4,016,139.
Preferred enhancing agents in accordance with this invention are the oxides of antimony, arsenic and bismuth, with the oxides of antimony being éspecially preferred. Antimony trioxide is the most preferred enhancing agent used in the compositions of this invention. As noted, the enhancing agent is supplied at the level of about 0.1-15 percent by weight. Preferably, the enhancing agent is used at a level of about 2-10 percent by weight.
The scope of the present invention includes the ; ~incorporation o other additlves in: the composition so far as to produce a particular end result. Such :
additives include, without limitation, heat stabllizers, light stabi~lizers, plasticizers, pigment~, preservatives, ultraviolet light stabilizers, fillers, antioxidants, antistatic ~agents and other materials well known to those ~ killed in the art, for example, as described in ::

1 3 ~

Modern Plastics EncYclopedia, Vol. 63, No. lOA, McGraw-Hill, Inc. (1986~.
The following preparations and examples are given to illustrate the invention and should not be construed as limiting its scope. All parts are by weight.

ExamPle 1 Step 1. 2,4,6-Tribromophenol (856 grams, 2.6 moles), phenol (6 grams), sodium carbonate (180 grams, 1.7 moles) and propylene glycol (1036 grams) are combined in a five-liter reactor equipped with a mechanical stirrer. The mixture is brought to 100C
with agitation and held for one hour.
1,2-Dibromoethane (1950 grams, 10.4 moles) is added to the reactor all at once. The temperature is returned to 100C and held for an additional three hours with high agitation. Without allowing the reaction mixture to cool, agitation is discontinued, . .
the phases are allowed to separate. Methanol (6 :
liters) is placed in a 12-liter reactor with mechanical stirrer. With the methanol being vigorously agltated, the lower phase from the :
S~ er reactor is added~to the methanol while :
keeping the lower phase warm enough to avoid :~ :
25~ ~olidification before the additlon is complete. The resulting methanol slurry i~ filtared to recover the product (~-bromoethyl-2,4,6- tribromophenyl etherJ
Compound Q). After drying in a vacuum oven at room 1~76~

--19~

temperature, 995 grams (87% of theory) of product with greater than 98% purity and less than one percent 1,2-bis(tribromophenoxy)-ethane are obtained.
Step II. Dibromononylphenol (860 gramsl 2.25 moles), phenol (5 grams), sodium carbonate (127 grams, 1.2 moles~ and propylene glycol (2100 grams) are combined in a S-liter reactor with mechanical stirrer. The mixture is heated slowly to 150C with agitation. Compound Q (995 grams, 2.25 moles) is added to the reaction portion-wise over one hour at 150C With vigorous agitation. The temperature and agitation are maintained for an additional four hours. With the agitation off, the reaction is allowed to cool. The upper phase is decanted and the lower phase is dissolved in methylene chloride (1 liter). After washing with dilute hydrochloric acid, the olvent is distilled, and volatile components are removed using~a wiped film evaporator 20 at 200C and 1.0 torr vacuum. The product, Compound A, weighs 1530 grams ~92.5%) of theory. Combined yield for the~two steps is about 80% of theory.
ExamPIe_2 ~
Step !. Dibromononylphenol (2270 grams, 6.0 25 mo;les)~ phenol (16 qrams), sodium carbonate (382 grams, 3.6 moles) and propylene glycol (3700 grams) are combined in a 12-liter reactor equipped with a mechanical stirrer and a Dean-Stark trap. The mixture is 13~ 7~ ~.33 slowly heated to 100C (30-60 minutes) with agitation and held at 100C for one hour. 1,2-Dibromoethane (4410 grams, 24.0 moles) is added to the reactor all at once. With vigorous agitation the mixture is heated to 130C and held for four hours. After cooling the reaction to 90-95C, water ~300 grams) is added and the mixture heated to reflux (~95C). The dibromoethane and water azeotrope is collected in the Dean-Stark trap. The dibromoethane is removed and the water returned to the reactor until no additional dibromoethane is recovered. The water is then also removed. If during the azeotropic distillation the pH of the water becomes acidic, the situation is corrected by adding additional sodium 15~ carbonate to the reaction mixture.
Step II. 2,4,6-Tribromophenol (1985 grams, 6.0 moles), phenol (14 grams), sodium carbonate (382 grams, 3.6 moles) and propylene glycol (2500 grams) are combined in a 5-liter reactor e~uipped with a `
~20~ mechanical stirrer. The mixture is heated slowly to 100C (30-60 minutes~) and~held for one hour with agitation. The reactlon mlxture from Step I lS
heated to 145C, and the contents o the 5-llter reactor are added to it. After~returning the 25~ temperature to 145C, the mixture is held at 145C
with~vigorous agitation for four hours. With the stirrer off, the reactor is cooled to 35C and the upper phase decanted. The lower phase is dissolved 13~7~

in methylene chloride (2.5 liter). After washing with dilute hydrochloric acid, the solvent is distilled, and volatile components are removed using a wiped film evaporator at 200C and 1.0 torr vacuum. The product, Compound A, weighs 3,480 grams, which is approximately 79% of its theoretical yield.
Example 3 Step I. Dibromononylphenol (983 grams, 2.6 moles), sodium carbonate (180 grams, 1.7 moles), 1,2-dibromoethane (1950 grams, 10.4 moles), tris(2-(2-methoxyethoxy)ethyl) amine or TDA-l (84 grams) are combined in a 3-liter reactor equipped with a mechanical stirrer and Dean-Stark trap. The mixture is heated to 130C and held for four hours.
After cooling, the mixture is filtered, and the excess dibromoethane is removed using a wiped film evaporator at 100C and 20 torr vacuum.
Step II. The product from Step I which is ::
predominantly ~-bromoethyl-dibromononylphenyl ether and TDA-l is combined with 2,4,6-tribromophenol (860 grams, 2.6 molesj~and aodlum carbonate ~180 grams, 1.7 ~; ~ moles) in a 3-liter reactor equipped with mechanical stirrer and Dean-Stark trap. The mixture is heated :
to l30C and held for five hours. Methylene chloride (2 liters) is placed in a 5-liter reactor eguipped with mechanical stirrer and reflux : :

13~7~

condenser. The still-hot product in the 3-liter reactor is slowly added to the methylene chloride.
This mixture is then washed with diluted hydrochloric acid. After distilling the methylene chloride, volatile components are removed using a wiped film evaporator at 200C and 1.0 torr vacuum.
The product, Compound A, weighs 1,410 grams which i5 approximately 74% of its theoretical yield.
ExamPle 4 Step I. 2,4,6-Tribromophenol (1,160 grams, 3.5 moleæ), lithium hydroxide monohydrate (7.5 grams), and ethylene glycol (2000 grams) are combined in a 5-liter reactor equipped with mechanical stirrer and subsurface gas inlet tube. The mixture is heated to 120C and ethylene oxide is introduced subsurface at a rate of three to four grams per minute with vigorous stirring. The pH of the reaction mixture is monitored with dampened pH indicator paper.
After approximately one hour, depending on the rate of ethylene oxide addition, the pH will change from slightly acidic to strongly basic. At this point, the ethylene oxide addltlon lS discontinued.
Between 180 grams and 200 grams of ethylene oxide will have been used. When the reaction has cooled below 100C, water (750 grams) is added. With the temperature at or still slightly above 70C, the ~; heavy slurry is filtered on a laboratory filtering centrifuge and washed on the filter cloth with 70C

13~ 7~

water (10 liter). The product is dried in a forced draft oven at 80C to constant weight. The product, ~-hydroxyethyl-2,4,6- tribromophenyl ether, weighs 1190 grams, which is approximately 91% of the theoretical yield.
Step II. Product from Step I (940 grams, 2.5 moles), and pyridine (3 liters) are combined in a 5-liter reactor equipped with mechanical stirrer.
After cooling the mixture to <5C, benzenesulfonyl chloride (883 grams, 5 moles) is added dropwise over one hour while keeping the temperature at ~5C. The mixture is allowed to slowly warm to room temperature after stirring for 16 hours at ~5C.
After filtering off the solids formed, the mixture is slowly added to a 12-liter reactor half-full With an ice/water slurry with vigorous agitation. The product is recovered by filtration and dried in a vacuum oven to constant weight. The product, 2-(2,4,6-tribromophenoxy)- ethyl benzene-sulfonate weighs 1,210 grams which is about 94% of the theoretical yield.
Step III. Same as Step~II of Example 1 except (2,4,6-tribromophenoxy~-ethyl benzenesulfonate ; ~ (1,1~60 grams, 2.25 moles) i~s used in place of Compound Q. The product, Compound AJ weighs 1540 gramB which is 93% of theory. Combined yield of the three steps is approximately 79% of its theoretical yi e ld .

1 3 ~

-2~-Example 5 A flame retardant composition was prepared by blending 20.0 parts halogenated unsymmetrical higher alkyl bisphenoxy alkane (Compound A); 69.0 parts ABS
resin, which is available from Borg-Warner Corporation as CYCOLAC GSM 1000; 5.0 parts chlorinated polyethylene, which is available from The Dow Chemical Company as TYRIN CPE-4213S, 5.0 parts antimony trioxide, which is available from M &
T Chemical Company as THERMOGUARD S; 0.5 parts stabilizer, which is available from Ciba Geigy *

Corporation as TINUVIN 770; and 0.5 parts antioxidant, which is available from Ciba Geigy Corporation as Irganox 1076.
Compound A is l-(tribromophenoxy)-2-(dibromononylphenoxy)-ethane, a halogenated unsymmetrical higher alkyl bisphenoxy alkane prepared in accordance with Example 1.
The resultant mixture was blended in a prep-center bowl (Model R6, C-.W.~ Brabender Instruments,~Inc., S. Hackensack, NJ~ at 200C until a~homogeneous mass developed. The admlxture was cooled, ground into chlps, and molded into test specimens. The chips were injection molded in a one~ounce injection molder~(ModeI HI-30 RS, Newbury Industries, Inc., Newbury, OH). Conditions for injection molding are givan in Table II. The ; resulting mixture had a bromine content of 10.8% by weight.

~6~k5 13~ 7~ 3 TABLE II

INJECTION MOLDING MACHINE PARAMETERS

Stock Temperature 430F
Mold Temperature 100F
Initlal Ram Pressure1900 psi : Secondary Ram Pressure 1000 psi : Total In~ection Time5 sec Cycle Time 25 sec :
:
Bloom observations were made on molded test plaques which were aged at 70C for at least 2 to 6 weeks. Periodic visual insPections were used to : 15 detect the presence of deposits on the speci~en surface.
EXAMPLES 6-ll Flame retardant compositions were prepared using the method o Example 5,; except that Compound 20 ~ A was replaced by bisphenoxy alkanes Compound B, Compound C, Compound D,~ Compound~E)~Compound G, and Compound~I, respectively in~prop~ortlon so as to maintain a ~10~. 8 percent by weight bromlne concentration in the result~ing polymer composition. The identity for these compounds are listed~i:n~Table III.

~ :

: ~ :
:

::

1~7~
-.~6-TABLE III

A l-(Tribrom~phenoxy)-2-(dibromononylphenoxy)-ethane B l-(Tribromophenoxy)-2-(dibromooctylphenoxy)-etharle C l-(Tribromophenoxy)-2-(dibromopentylphenoxy-ethane D l-(Tribromophenoxy)-2~(dlbromododecylphenoxy)-ethane : E l-(Tetrabromomethylphenoxy)-2-(dibromooctylphenoxy)-ethane F bis-(Dibromononylphenoxy)-ethane : . G l-(Tetrabromomethylphenoxy)-2-(dibromononylphenoxy)-ethane I l-(Pentabromophenoxy) 2-(dibromononylphenoxy)-ethane J bis-tTribromophenoxy)-ethane K bis-tTetrabromomethylphenoxy)-methane L bis-tTribromophenoxy)-decane Flame retardant compositioDs were prepared using the method of Example S, except that Compound A was replaced:by Compound J, Compound F, Compound K, and Compound L, respectively in a proportion so :
: 20 as to maintain a 10.8 percent by weight bromine , concentration in the resulting polymer composition.
Identlty for these Compounds J, F,~ K, and L are listed in Table II~
Flame retardancy and~physical:properties of the 25~ ~va~rlou~ lnjected molded~samples obtalned from Examples S-ll are reported~in Table IV which identifiPs the test procedures employed, all of ;which are well known to~those skilled in the art.

:

~ 3 ~

TABLE I V

Example Notched Heat Flamma- Tensile Elonga- Flexural Flexural Izod Deflec- bility Strength tion Strength Modulus ft-lb~ln tion UL-94 p3i ~ psi 10 psi ASTM F ASTM ASTM ASTM AST~

:
4.2156 V-0 4aoo40 7900 Z.60 6 3.9~53 V-0 510037 8400 2.~0 7 4.1~51 V-0 550021 9100 3.00 8 3.415~ V-0 450036 7400 2.50 9 3,7156 V-0 5200230 8000 2.80 4.6~56 V-0 490050 8100 2.70 ~ ~ 11 4.9 158 V-0 5100 55 8400 Z.80 `: Comp 1 2.5 151 V-05400 12 9400 3.20 : Co~p~2 3.8 140 V-0 3300 4 : 3600 1.90 ~Comp~ 3 Comp:4 4.0 150 ~ V-0: 4800 ~ 52 B300 3.09 :: ~ ~ : :~ : :
Ex ple ~ ~elt Hardn 9 Bloom Light ~ Yollo~ne~ Yollowness Flow R-Scal- 70 C ~Stabllity lndex-~ ~ Index g A 0 ~in ~ ~5~e ~ : D-lta~E~ ~initlal 300 br~
25~ text) ASTn ASTM ~: AST~
; AS~ ASTM ASIM~ ~ ASTM ~ ASTM
;D-1238 D-785 D-2565 ~D-15t5 D-19Z5 :: : : ; :

-28- 13~.7~

TABLE IV I CON~INUEI) 3 _ _ _ 2.2 80 No 1.0 16.7 18.6 6 2.0 84 No 0.7 16.6 18.1 7 3 . 4 86 No 8 2 . 3 73 No 1. 3 17. 2 ZO . O
9 2.G 73 No 0.2 16.2 16.4 : :
2 . 3 84 No 3 . 8 17 . 0 ~ 25 . 2 O ~ 1 . 8 ~5 No ~ 6 . 0 17 . 0 30, 0 Comp ~I Z.l 93 Yes 0.9 16.4 ~17.7 Con p 2 -- 36 Yes 0 . 3 17 . 6 17 . 8 :
Comp 3 Yes Comp 4 1. 6 75 Yes ~ . 2 ~: 15 Table IV shows the results o the experimental evaluati~ns o various test specimens and may be summarized as follows.
Example 5 illustrates a flame retardant ABS .-formulation incorporating halogenated unsymmetrical higher aikyl bisphenoxy alkane in accorda~ce:with thl~ invention.:~A~flammablllty rating of ~-O~was achieved, and bloom~was not~observed. : :~
Comparatlve Examp~le~s~1-4~ehow that prior;art 25:~symmetrica~blsphenoxy~compound,~ when uaed~in~V-O
formulation, migrate:~(bloom)~from ABS resin.
Examples;6-11;illustrate;flame~retardant :: : formulations incorporating other~halogenated : : :

' :~ :
:::

1 31 7~

unsymmetrical higher alkyl bisphenoxy alkanes within the scope of this invention.
It is especially important to note that ABS
resins incorporating halogenated unsymmetrical higher alkyl bisphenoxy alkanes of this invention do not bloom whereas symmetrical bisphenoxy alkanes do bloom or tend to migrate from the resin compoæitions. It is to be noted that ABS resins incorPorating the halogenated unsymmetrical higher alkyl bisphenoxy alkanes of this invention exhibit excellent resistance to light instability, to thermal migration of flame retarding agents, and have improved physical properties, such as impact strength and tensile elongation.

Flame retardant compositions were prepared using the method of Example 5, except that Compound A was partially replaced by Compound J in proportion as specified in Table V, so as to maintain a constant weight of bromine-containing flame retar-dant.

A flame retardant composi~tion was prepared ` using the method of Example;5, except that Compound ` 25 A was replaced by Compound J in proportion as : ~ specified in Table V.

:
, , ~3~7~

TABLE V
BROMINE-CONI'AINING COMPOUND, pbw EXI~MPLECOtlPOVND A COMPOUND J E~LOOM

20.0 0.0 N0 IZ 19.0 1.0 N0 1~ 18.0 2.0 N0 14 16.0 4.0 N0 10 COMP 5 0 . O 20 . O YES
COtSP 6 0 . 0 1. 0 YES

Table V~shows the results of experimental evaluation of the various test specimens and may be summarized as follows:
Use of the halogenated unsymmetrical higher alkyl bisphenoxy alkanes of this invention in ABS
: ; resin formulations also suppresses bloom. In the case of bis(tribromophenoxy)-ethane~(Compound J), severe bloom was noted in high (Comparative Example;5) and low~(Comparative Example 6) loading :~ : : levels. Examples 12-14:show no evidence of bloom in~compositions comprlslng mixtures of the agent=
: of this invention~with~:bis(tribromophenoxy)-ethane 29 (Compound J:). Thu~ the:;pre~sence of Compound A
retards or suppress~es the blooming that would : : otherwise occur due to the presence of : bis(trlbromophenoxy~-ethane~(Compound J).

: ~

1 3 ~

From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and without departing from the spirit and scope thereof can S make various changes and modifications of the invention to adopt to its various usages and condltlons.

:

~:: :

:
:
:

Claims (13)

1. A halogenated unsymmetrical higher alkyl bisphenoxy alkane of the structure wherein X is bromine or chlorine; R1 is straight or branched alkyl from methyl to dodecyl (C1 to C12); z is an integer from 2 to 5; n is 0, 1, or

2; R2 is straight or branched alkyl selected from the group consisting of sec-butyl, (sec C4H9), pentyl (C5H11), hexyl (C6H13), heptyl (C7H15) octyl (C8H17), nonyl (C9H19), decyl (C10H21), undecyl (C11H23) and dodecyl (C12H25); y is 0, 1, or 2; R3 is a straight or branched alkylene group from methyl to docedyl (C1 to C12); and if n is 1, R1 is not R2.
2. A composition as claimed in claim 1 wherein X
is bromine.

3. A composition as claimed in claim 2 wherein R2 is octyl (C8H17).

4. A composition as claimed in claim 2 wherein R2 is nonyl (C9H19).

5. A composition as claimed in claim 4 wherein R3 is ethylene.

6. A halogenated unsymmetrical higher alkyl 10 bisphenoxy alkane of the structure:

7. A halogenated unsymmetrical higher alkyl bisphenoxy alkane of the structure:

8. A halogenated unsymmetrical higher alkyl bisphenoxy alkane of the structure:

9. A non-blooming flame retardant acrylonitrile-butadiene-styrene resin composition comprising: a normally flammable acrylonitrile-butadiene-styrene resin; as a flame retardant agent, an effective amount of halogenated unsymmetrical higher alkyl bisphenoxy alkane to render the composition flame retardant, the bisphenoxy alkane being a compound of the structure:

wherein X is bromine or chlorine; R1 is straight or branched alkyl from C1 to C12; z is an integer from 2 to 4; n is 0, 1, or 2; R2 is straight or branched alkyl selected from the groups consisting of sec-butyl (sec C4H9), pentyl (C5H11), hexyl (C6H13), heptyl (C7H15), octyl (C8H17), nonyl (C9H19), decyl (C10H21), undecyl (C11H23), and dodecyl (C12H25); y is 0, 1, or 2;
R3 is straight or branched alkylene from C1 to C12; and if n is 1, R1 is not R2; and a flame retardant enhancing agent.

10. A composition, as claimed in claim 9, wherein the composition comprises about 50 to about 90 percent acrylonitrile-butadiene-styrene resin, about 5 to about 30 percent halogenated unsymmetrical higher alkyl bisphenoxy alkane and about 0.1 to about 15 percent enhancing agent, all by weight of the flame retardant ABS composition.

11. A composition, as claimed in claim 9 wherein the enhancing agent is selected from the group consisting of the oxides and halides of groups IV-A and V-A of the periodic table; organic or inorganic compounds of phosphorous, nitrogen, boron or sulfur; or oxides and halides of zinc, magnesium and titanium.

12. A composition as claimed in claim 9, wherein the enhancing agent is antimony trioxide.

13. A composition as claimed in claim 9, wherein the halogenated unsymmetrical higher alkyl bisphenoxy alkane is selected from the group consisting of:
1-(tribromophenoxy)-2-(dibromononylphenoxy)-ethane;
1-(tribromophenoxy)-2-(dibromooctylphenoxy)-ethane;
1-(tribromophenoxy)-2-(dibromopentylphenoxy)-ethane;
1-(tribromophenoxy)-2-(dibromododecylphenoxy)-ethane;
1-(tetrabromomethylphenoxy)-2-(dibromooctylphenoxy)-ethane;
1-(tetrabromomethylphenoxy)-2-(dibromononylphenoxy)-ethane;
1-(pentabromophenoxy)-2-(dibromononylphenoxy)-ethane.