WO2008027780A1

WO2008027780A1 - Preparation of decahalodiphenyl oxide

Info

Publication number: WO2008027780A1
Application number: PCT/US2007/076608
Authority: WO
Inventors: Alvin E. Harkins; James E. Boone
Original assignee: Albemarle Corporation
Priority date: 2006-08-29
Filing date: 2007-08-23
Publication date: 2008-03-06
Also published as: TW200812949A

Abstract

This invention provides a process of preparing reaction-derived decahalodiphenyl oxide of high purity. The process comprises cofeeding separate feeds of (a) diphenyl oxide and/or partially brominated diphenyl oxide and (b) bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine to a refluxing reaction mixture comprising bromine and at least one Lewis acid bromination catalyst so that high purity decahalodiphenyl oxide is formed.

Description

PREPARATION OF DECAHALODIPHENYL OXIDE

TECHNICAL FIELD

[0001] This invention relates to the preparation of decahalodiphenyl oxide products of high purity and their use in flammable materials.

BACKGROUND

[0002] Decabromodiphenyl oxide (DBDPO) is a time-proven flame retardant for use in many flammable macromolecular materials, e.g., thermoplastics, thermosets, cellulosic materials, and back coating applications.

[0003] DBDPO is presently sold as a powder derived from the bromination of diphenyl oxide or a partially brominated diphenyl oxide containing an average of about 0.7 bromine atom per molecule of diphenyl oxide. Such bromination is conducted in excess bromine and in the presence of a bromination catalyst, usually AlCl₃. The operation is typically conducted at 177 °F (ca. 80.5 °C) with a 2 to 3 hour feed time. The powdered products are not 100% DBDPO, but rather are mixtures that contain up to about 98% DBDPO and about 1.5%, or a little more, of nonabromodiphenyl oxide co-product. As a partially halogenated product, this amount of nonabromodiphenyl oxide is considered problematic by some environmental entities.

[0004] It would therefore be desirable to provide process technology enabling preparation of DBDPO products having a higher degree of halogenation which contain less nonabromodiphenyl oxide, such as products comprising (i) at least 96% of DBDPO and (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, preferably not exceeding 0.3%, and still more preferably, not exceeding about 0.2%. It would be especially desirable if such technology could produce DBDPO products comprising (i) at least 99% of DBDPO and (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, preferably not exceeding 0.3%, and still more preferably, not exceeding about 0.2%.

SUMMARY OF INVENTION

[0005] It has now been found possible to directly produce decahalodiphenyl oxide products having a higher degree of halogenation and lower contents of nonabromodiphenyl oxides without recourse to recrystallization or chromatographic purification steps. This can be accomplished by using bromine chloride as the bromination agent, which minimizes the formation of nonabromodiphenyl oxide to amounts less than 0.5%, while forming a DBDPO product containing more than 96% of DBDPO. Thus, a feature of this invention is that it has been found possible to prepare reaction-derived perhalogenated diphenyl oxide products in yields of about 99.5% or more. In these perhalogenated products, the majority of the product is decabromodiphenyl oxide (typically in an amount of about 96% or more), a small amount of the product is nonabromochlorodiphenyl oxide (usually in an amount of 0.3 to about 3%), and a small amount of nonabromodiphenyl oxide (normally an amount of about 0.5% or less) is present in the perhalogenated product.

[0006] An embodiment of this invention is a process of preparing reaction-derived decahalodiphenyl oxide of high purity. The process comprises cofeeding separate feeds of

(a) diphenyl oxide and/or partially brominated diphenyl oxide and

(b) bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine to a refluxing reaction mixture comprising bromine and at least one Lewis acid bromination catalyst so that high purity decahalodiphenyl oxide is formed.

[0007] Another embodiment of this invention is a reaction-derived product containing (i) at least 96% of decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, and (iii) nonabromochlorodiphenyl oxide in an amount of about 0.1% to about 3%.

[0008] A feature of this invention is that it has been found possible to prepare reaction- derived decabromodiphenyl oxide products containing:

A) (i) at least 96% decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, and (iii) nonabromochlorodiphenyl oxide in an amount of about 0.1% to about 3%.

B) (i) at least 97% decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding about 0.3%, (iii) nonabromochlorodiphenyl oxide in an amount of about 0.1% to about 3%;

C) (i) at least 99% decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding about 0.3% (iii) nonabromochlorodiphenyl oxide in an amount of about 0.1% to about 0.7%; and

D) (i) at least 96% decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, and (iii) nonabromochlorodiphenyl oxide in an amount of about 0.2% to about 2.5%.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Fig. 1 is a copy of a GC trace of the product of Example 1 hereinafter.

[0010] Fig. 2 is a copy of a GC trace of the product of Example 2 hereinafter.

[0011] These and other embodiments and features of this invention will be still further apparent from the ensuing description, accompanying drawings, and appended claims.

FURTHER DETAILED DESCRIPTION OF THE INVENTION

[0012] On the basis of studies conducted in our laboratories, one of the prime difficulties in producing decabromodiphenyl oxide (DBDPO) is the existence of an equilibrium between nonabromodiphenyl oxide and decabromodiphenyl oxide. This equilibrium can be depicted as follows:

Br₉-DPO + Br₂ ^ Br₁₀-DPO + HBr

Reducing hydrogen bromide content in the reactor enables a shift to the right in this equilibrium so that the amount of nonabromodiphenyl oxide is diminished and more of the desired decabromodiphenyl oxide forms and precipitates with less nonabromodiphenyl oxide being coprecipitated within the decabromodiphenyl oxide particles. Pursuant to this invention, using bromine chloride as the bromination agent is believed to reduce the HBr content in the reactor and thus reduce the amount of nonabromodiphenyl oxide in the product. [0013] As used throughout this document, the term "reaction-derived" means that the composition of the product is reaction determined and not the result of use of downstream purification techniques, such as recrystallization or chromatography, or like procedures that can affect the chemical composition of the product. Adding water or an aqueous base such as sodium hydroxide to the reaction mixture to inactivate the catalyst, and washing away of non-chemically bound impurities by use of aqueous washes such as with water or dilute aqueous bases are not excluded by the term "reaction-derived." In other words, the products are directly produced in the synthesis process without use of any subsequent procedure to remove or that removes nonabromodiphenyl oxide and/or other nonahalodiphenyl oxides from decahalodiphenyl oxides. [0014] As used throughout this document, the term "decahalodiphenyl oxide" refers to perhalogenated diphenyl oxides that contain only bromine or contain only bromine and chlorine. Examples of decahalodiphenyl oxides include decabromodiphenyl oxide and nonabromochlorodiphenyl oxide.

[0015] As used throughout this document, the term "high purity" means that the reaction- derived decahalodiphenyl oxide product comprises about 99% or more decahalodiphenyl oxide species, preferably in which nonabromodiphenyl oxide is present in an amount not exceeding about 0.5%. Preferably the processes of the invention form reaction-derived products which comprise (i) at least 99.5% of decahalodiphenyl oxide and (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, preferably not exceeding 0.3%. [0016] For the purposes of this invention, unless otherwise indicated, the % values given for decabromodiphenyl oxide (DBDPO), nonabromochlorodiphenyl oxide, and nonabromodiphenyl oxide are to be understood as being the area % values that are derived from gas chromatography analysis. A recommended procedure for conducting such analyses is presented hereinafter.

[0017] This invention enables the preparation of perhalogenated diphenyl oxide products that are derived from the bromination of diphenyl oxide and/or partially brominated diphenyl oxide with lower contents of nonabromodiphenyl oxide. For example, it is now possible to prepare reaction-derived decabromodiphenyl oxide of a purity of at least 96% while having nonabromodiphenyl oxide in an amount of 0.5% or less. Indeed, it is deemed possible to prepare reaction-derived products that contain at least 99% decabromodiphenyl oxide and that contain amounts of nonabromodiphenyl oxide not exceeding 0.3%. More preferably, the amount of nonabromodiphenyl oxide does not exceed about 0.2%. These reaction products also typically contain nonabromochlorodiphenyl oxide in an amount of about 0.2% to about 3%. Such products can be said to be "reaction-derived" since they are reaction determined and not the result of use of downstream purification techniques, such as recrystallization, chromatography, or like procedures. In other words, the products having such high halogenation are directly produced in the synthesis process apart from use of subsequent purification procedures as applied to the recovered or isolated products. [0018] Bromination of diphenyl oxide and/or partially brominated diphenyl oxides is known in the art. See in this connection U.S. Pat. No. 4,778,933. [0019] Various iron and/or aluminum Lewis acids can be used as the bromination catalyst. These include the metals themselves such as iron powder, aluminum foil, or aluminum powder, or mixtures thereof. Preferably use is made of such catalyst materials as, for example, ferric chloride, ferric bromide, aluminum chloride, aluminum bromide, or mixtures of two or more such materials . More preferred are aluminum chloride and aluminum bromide with addition of aluminum chloride being more preferred from an economic standpoint. It is possible that the makeup of the catalyst may change when contained in the reaction mass . The Lewis acid should be employed in an amount sufficient to effect a catalytic effect upon the bromination reaction being conducted. Typically, the amount of Lewis acid used will be in the range of about 0.06 to about 2 wt%, and preferably in the range of about 0.2 to about 0.7 wt% based on the weight of the bromine being used.

[0020] If desired, a suitable solvent can be included in the reaction mixture. This can be advantageous in that one can have a higher reaction temperature and possibly a lower HBr concentration in the reaction mixture thereby giving higher purity decahalodiphenyl oxides. Among such suitable solvents are methylene bromide (dibromomethane) and bromoform. [0021] In the various embodiments of this invention, diphenyl oxide (DPO; diphenyl ether) itself, one or a mixture of partially brominated diphenyl oxides , or a mixture of DPO and one or more partially brominated diphenyl oxides can be used. Partially brominated DPO, which can be used in the practice of this invention, typically contains in the range of about 0.5 to about 4 atom(s) of bromine per molecule of DPO. Partially brominated diphenyl oxides with more than about 4 atoms of bromine per molecule can be used in the processes of this invention.

[0022] The diphenyl oxide and/or partially brominated diphenyl oxide can be fed as solids, but preferably the feed is in molten form or as a solution in a solvent such as methylene bromide or bromoform. To prevent freeze up in the feed conduit, diphenyl oxide is desirably fed at a temperature of in the range of at least about 28 to about 35 °C. Higher temperatures can be used if desired.

[0023] Throughout this disclosure reference is often made to "bromine chloride", a term commonly used by chemists to describe a substance made by combining bromine and chlorine. This substance is generally represented in the chemical arts by the molecular formula BrCl or Br-Cl. We wish to forestall any quibbling based on hypertechnicalities, to make note of the fact that there is evidence to indicate that "bromine chloride" itself is an equimolar mixture of elemental bromine and elemental chlorine, and further that under ordinary conditions 100% pure BrCl probably does not exist as such, but rather the equimolar mixture itself apparently exists as a mixture of about 60% BrCl, 20% Br₂, and 20% Cl₂. But whatever it is, the substance known to chemists as "bromine chloride" is what is being referred to. And reference herein to a mixture of "bromine chloride and bromine" or a mixture of "bromine chloride and chlorine" simply means that besides the equimolar mixture of bromine and chlorine known to chemists as "bromine chloride", whatever its makeup, there is a an excess amount of bromine or chlorine, respectively, over the equimolar amount of bromine and chlorine. In the practice of this invention, the use of bromine chloride or bromine chloride and bromine is preferred.

[0024] In the processes of this invention, bromine chloride (or bromine chloride and bromine, or bromine chloride and chlorine) can be used in various amounts, from significantly less than that theoretically needed to perhalogenate the diphenyl oxide and/or partially brominated diphenyl oxide to an excess relative to the amount theoretically needed to perhalogenate the diphenyl oxide and/or partially brominated diphenyl oxide. More specifically, preferred amounts of bromine chloride (or bromine chloride and bromine, or bromine chloride and chlorine) are in the range of about 30% to about 130% relative to the amount theoretically needed to perhalogenate the diphenyl oxide and/or partially brominated diphenyl oxide; more preferred are in the range of about 50% to about 115% relative to the amount theoretically needed to perhalogenate the diphenyl oxide and/or partially brominated diphenyl oxide. Particularly preferred ranges are about 50% to about 60% and about 90% to about 115% relative to the amount theoretically needed to perhalogenate the diphenyl oxide and/or partially brominated diphenyl oxide. Larger amounts of bromine chloride than 130% of that theoretically needed for perhalogenation are not expected to further decrease the amount of nonabromodiphenyl oxide in the product, while an increase in the amount of chlorine in the product is expected. Less chlorine is observed in the product when less than a stoichiometric amount of bromine chloride relative to that theoretically needed for perhalogenation is used; however, a concomitant increase in the amount of nonabromodiphenyl oxide has been observed. It is possible to use less than the stoichiometric amount of bromine chloride theoretically needed for perhalogenation because, as is known in the art, the bromine present in the reaction mixture acts as both a solvent and as a bromination agent for the diphenyl oxide and/or partially brominated diphenyl oxide. [0025] In this connection, the total amount of halogen in the reaction mixture inclusive of the bromine initially in the reactor and that fed as bromine chloride (or bromine chloride and chlorine or bromine chloride and chlorine) is preferably at least about 15 moles per mole of diphenyl oxide and/or partially brominated diphenyl oxide. When the feed is diphenyl oxide, the reaction mixture typically will contain in the range of at least about 14 moles of total halogen per mole of diphenyl oxide to be fed thereto, and preferably, the reaction mixture contains in the range of about 5 to about 30 moles of total halogen per mole of diphenyl oxide to be fed thereto. It is possible to use more than 30 moles bromine per mole of diphenyl oxide but this offers no advantage. When the feed is partially brominated diphenyl oxide, the reaction mixture preferably contains in the range of about 14 to about 22 moles of total halogen per mole of partially brominated diphenyl oxide. When the feed is a mixture of diphenyl oxide and partially brominated diphenyl oxide, the amount of total halogen in the reaction mixture is preferably in the range of about 5 to about 25 moles of halogen per the combined total amount of moles of diphenyl oxide and partially brominated diphenyl oxide. [0026] The amount of bromine initially in the reactor (before either of the cofeeds is commenced) is generally at least about 5 moles per mole of diphenyl oxide and/or partially brominated diphenyl oxide to be fed, and preferably is 5 to 10 moles or more per mole of diphenyl oxide and/or partially brominated diphenyl oxide to be fed. Amounts of bromine at the higher end of the range are preferred. When the amount of total halogen desired is greater than the combined amount of bromine initially in the reactor and the bromine chloride (or bromine chloride and chlorine or bromine chloride and chlorine) being fed, the additional bromine can be fed as a separate feed or included in the bromine chloride feed (i.e., the bromine chloride feed will be bromine chloride and bromine).

[0027] In the practice of this invention, the bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine may be fed above the surface, at the surface, or below the surface of the reaction mass. It is preferred to feed the bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine subsurface to the reaction mass. Subsurface feeding minimizes the possibility of splattering which can occur when, for example, liquid bromine chloride strikes the surface of the reaction mass. It is to be noted that when the term "subsurface" is used anywhere in this document, including the claims, the term does not denote that there must be a headspace above the reaction mass. For example, if the reaction mass is completely fills a reactor (with equal rates of incoming and outgoing flows), the term "subsurface" means in this case that the substance being fed subsurface is being fed directly into the body of the reaction mass, the surface thereof being defined by the enclosing walls of the reactor.

[0028] The processes of this invention comprise cofeeding (a) diphenyl oxide and/or partially brominated diphenyl oxide and (b) bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine and as separate feeds to a refluxing reaction mixture of bromine and at least one Lewis acid bromination catalyst. That the feeds of the diphenyl oxide and/or partially brominated diphenyl oxide and the bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine are cofeeds means that there is overlap in their occurrence, i.e., the cofeeds are conducted concurrently or substantially concurrently. The cofeeds do not need to begin at the same instant in time; either feed may be commenced before the other with no materially adverse effect. Similarly, the cofeeds need not end at exactly the same instant in time; one feed or the other may be stopped before the other, again without materially adverse effect. Interruptions in either feed, or both feeds, are permissible in the practice of this invention as long as such interruptions do not have a materially adverse effect. It is recommended and preferred that the feed of diphenyl oxide and/or partially brominated diphenyl oxide is initiated first when the feeds are not initiated at the same time in order to minimize the extent of chlorination of the diphenyl oxide and/or partially brominated diphenyl oxide. It is also recommended and preferred that the feed of diphenyl oxide and/or partially brominated diphenyl oxide is stopped first when the feeds are not stopped at the same time, again to minimize the extent of chlorination of the diphenyl oxide and/or partially brominated diphenyl oxide.

[0029] The processes of this invention may be conducted at atmospheric, subatmospheric, or superatmo spheric pressure. Operation at atmospheric or superatmo spheric pressure is preferred; more preferable is operation at atmospheric pressure. The temperature required for refluxing to effect the halogenation will vary with the pressure and the concentrations of diphenyl oxide, partially halogenated diphenyl oxides, nonabromodiphenyl oxide, and decabromodiphenyl oxide present in the reaction mass. [0030] Termination of the bromination reaction is typically effected by deactivating the catalyst with water and/or an aqueous base such as a solution of sodium hydroxide or potassium hydroxide.

[0031] The decahalodiphenyl oxide products produced by the processes of this invention are compositions of this invention. As mentioned above, these products comprise at least 96% decabromodiphenyl oxide, nonabromodiphenyl oxide in an amount not exceeding 0.5%, and nonabromochlorodiphenyl oxide, often in an amount of about 0.1% to about 3%. Preferably, the nonabromochlorodiphenyl oxide is present in an amount of about 0.2% to about 2.5%. The presence of such small amounts of chlorine in the decahalodiphenyl oxide products is not considered deleterious.

[0032] The decahalodiphenyl oxide products formed in proces ses of this invention are white or slightly off-white in color. White color is advantageous as it simplifies the end-users task of insuring consistency of color in the articles that are flame retarded with the DBDPO products.

[0033] The decahalodiphenyl oxide products formed in the processes of this invention may be used as flame retardants in formulations with virtually any flammable material. The material may be macromolecular, for example, a cellulosic material or a polymer. Illustrative polymers are: olefin polymers, cross-linked and otherwise, for example homopolymers of ethylene, propylene, and butylene; copolymers of two or more of such alkene monomers and copolymers of one or more of such alkene monomers and other copolymerizable monomers, for example, ethylene/propylene copolymers, ethylene/ethyl acrylate copolymers and ethylene/propylene copolymers, ethylene/acrylate copolymers and ethylene/vinyl acetate copolymers; polymers of olefinically unsaturated monomers, for example, polystyrene, e.g. high impact polystyrene, and styrene copolymers, polyurethanes; polyamides; polyimides; polycarbonates; polyethers; acrylic resins; polyesters, especially poly(ethyleneterephthalate) and poly(butyleneterephthalate); polyvinyl chloride; thermosets, for example, epoxy resins; elastomers, for example, butadiene/styrene copolymers and butadiene/acrylonitrile copolymers; terpolymers of acrylonitrile, butadiene and styrene; natural rubber; butyl rubber and polysiloxanes. The polymer may be, where appropriate, cross-linked by chemical means or by irradiation. The decahalodiphenyl oxide products of this invention can be used in textile applications, such as in latex-based back coatings. [0034] The amount of a decahalodiphenyl oxide product of this invention used in a formulation will be that quantity needed to obtain the flame retardancy sought. It will be apparent to those skilled in the art that for all cases no single precise value for the proportion of the product in the formulation can be given, since this proportion will vary with the particular flammable material, the presence of other additives and the degree of flame retardancy sought in any give application. Further, the proportion necessary to achieve a given flame retardancy in a particular formulation will depend upon the shape of the article into which the formulation is to be made, for example, electrical insulation, tubing, electronic cabinets and film will each behave differently. In general, however, the formulation, and resultant product, may contain from about 1 to about 30 wt%, preferably from about 5 to about 25 wt% decahalodiphenyl oxide product of this invention. Masterbatches of polymer containing decahalodiphenyl oxide, which are blended with additional amounts of substrate polymer, typically contain even higher concentrations of decahalodiphenyl oxide, e.g., up to 50 wt% or more.

[0035] It is advantageous to use the decahalodiphenyl oxide products of this invention in combination with antimony-based synergists, e.g., Sb₂O₃. Such use is conventionally practiced in all decahalodiphenyl oxide applications. Generally, the decahalodiphenyl oxide products of this invention will be used with the antimony based synergists in a weight ratio ranging from about 1 : 1 to 7 : 1 , and preferably of from about 2: 1 to about 4:1. [0036] Any of several conventional additives used in thermoplastic formulations may be used, in their respective conventional amounts, with the decahalodiphenyl oxide products of this invention, e.g., plasticizers, antioxidants, fillers, pigments, UV stabilizers, etc. [0037] Thermoplastic articles formed from formulations containing a thermoplastic polymer and DBDPO product of this invention can be produced conventionally, e.g., by injection molding, extrusion molding, compression molding, and the like. Blow molding may also be appropriate in certain cases.

RECOMMENDED GAS CHROMATOGRAPHIC PROCEDURE

[0038] The gas chromatography is on a Hewlett-Packard 5890 gas chromatograph using a 12QC5 HTS capillary column, 12 meter, 0.15μ film thickness, 0.53mm diameter, part number 054657, available from SGE, Inc, (SGE Inc., 2007 Kramer Lane, Austin, Texas 78758). Conditions were: 1:10 split injection, column head pressure 9 psig (ca. 1.63xlO⁵ Pa), injector temperature 325 °C, flame ionization detector temperature 350 °C, and column temperature 300 °C isothermal. The carrier gas was helium. Samples were prepared by dissolving, with warming, 0.05 grams in 10 mL of dibromomethane and injection of 1 microliter of this solution. The integration of the peaks was carried out using Target Chromatography Analysis Software from Thru-Put Systems, Inc. (5750 Major Blvd., Suite 200, Orlando FL 32819; currently owned by Thermo Lab Systems). However, other and commercially available software suitable for use in integrating the peaks of a chromatograph may be used. [0039] The GC procedure described above provides a trace having several peaks. The first peak is deemed to be the meta- and para-hydrogen isomers of nonabromodiphenyl oxide. The second peak is deemed to be the ortho-hydrogen isomer of nonabromodiphenyl oxide. The third and fourth peaks are deemed to be nonabromochlorodiphenyl oxides. The main peak, of course, is decabromodiphenyl oxide.

[0040] The following examples are presented for purposes of illustration, and are not intended to impose limitations on the scope of this invention.

EXAMPLE 1

[0041] To a 250 mL pressure bottle were added 274.3 g of Br₂ and 105.5 g of Cl₂ (2.97 equivalents of BrCl, 10% excess). The pressure bottle was equipped with a Vβ-inch (outer diameter) diptube. A reactor was configured from a 1 -liter Morton flask with a mechanical stirrer, thermocouple, Friedrich condenser (2° C cooling water on condenser), a diptube (for diphenyl oxide feed) having an inner diameter of 1/32-inch (ca. 0.08 cm), and another diptube (for BrCl feed) having an outer diameter of Vβ-inch (ca. 0.32 cm), and heated with a heating mantle.

[0042] The reactor was charged with 3.16 g of AlCl₃ and 711 g of bromine. Diphenyl oxide (46.1 g, 0.271 mol) and the Br₂/Cl₂ mixture (BrCl) were cofed to the reactor during 124 minutes at 55 ° C to 57 °C. The rate of addition was at a proportion of about 8.2 g Br₂/Cl₂ mixture (BrCl) per gram of DPO, such that the addition of both was completed at the same time. The mixture in the reactor was refluxed for 10 minutes after the cofeeds had ended, and deionized H₂O was added. The reactor was set for distillation. The halogen (mostly Br₂, but also comprised of BrCl and Cl₂) was distilled off. When most of the halogen was gone, more deionized water was added. The remaining halogen was distilled off to 100⁰C. The remaining mixture was cooled to 6O⁰C, and 30 mL of 25% NaOH was added to pH 13-14. The resultant mixture was filtered and washed well with deionized water. A sample was subjected to GC analysis. The GC trace showed the product to contain 0.26% Br₉DPO (meta and para hydrogen isomers only), 2.52% Br₉ClDPO, and 97.2% Br₁₀DPO. None (less than 0.02%) of the ortho hydrogen isomer of Br₉DPO was detected. The sample was oven dried. [0043] The drawings show illustrative GC traces formed using the recommended gas chromatographic procedure described hereinabove. In these traces, the abscissa is time in minutes and the ordinate is the detector response. A copy of the GC trace of the product formed in Example 1 appears as Fig. 1. In Fig. 1, the peak at 1.358 represents the area percentage of what is deemed to be the meta and para isomers of nonabromodiphenyl oxide. No peak for the ortho-isomer of nonabromodiphenyl oxide was observed. The peaks at 2.103 and 2.200 were deemed to be Br₉ClDPO isomers. The peak at 2.649 represents the area percentage of decabromodiphenyl oxide.

EXAMPLE 2

[0044] Example 1 was repeated, with the following differences. A Vigreux column was placed between the reactor and the condenser. The amounts of the reagents were 302 g of Br₂ and 53.1 g of Cl₂ in the pressure bottle, 3.4 g Of AlCl₃ and 698 g of bromine charged to the reactor, and 47.4 g of diphenyl oxide. Diphenyl oxide (2 grams) was added to the reactor before the BrCl addition was begun, after which the diphenyl oxide and BrCl were added at rates such that addition of both was completed at about the same time. Reaction temperature was 56 °C throughout the additions. The mixture was refluxed 4 minutes longer, and then worked up as in Example 1. The GC trace showed the product to contain 0.31% Br₉DPO (0.17% combined of the meta and para hydrogen isomers, and 0.14% of the ortho hydrogen isomer), 0.40% Br₉ClDPO, and 99.29% Br₁₀DPO.

[0045] Fig. 2 is a copy of the GC trace of the product formed in Example 2. As in Fig. 1, the abscissa is time in minutes and the ordinate is the detector response. In the trace of Fig. 2, the peak at 1.356 represents the area percentage of what is deemed to be the meta and para isomers of nonabromodiphenyl oxide. The peak at 1.456 represents the area percentage of the isomer deemed to be the ortho isomer of nonabromodiphenyl oxide. The peaks at 2.124 and 2.198 were deemed to be Br₉ClDPO isomers. The peak at 2.649 represents the area percentage of decabromodiphenyl oxide.

[0046] The use of the term "concurrent" does not exclude the possibility of inconsequential interruptions taking place during the cofeeds, provided that the time intervals are of sufficiently short duration to cause no material adverse effect upon the overall process. Nor does the term "concurrent" imply that the cofeeds must start at exactly the same moment in time.

[0047] A feature of this invention is the concurrent cofeeding referred to above. It is again to be emphasized that the term "concurrent" does not imply that the cofeeds must start at exactly the same time or that they must stop at exactly the same moment in time. It should also be understood that while the concurrent cofeeds are preferably continuous concurrent feeds, slight interruptions in one or both feeds are acceptable provided that the duration of the interruption is sufficiently small as to cause no material disruption in the reaction. Thus as used herein, the terms "concurrent" and "continuous" should be understood to embrace the minor departures just referred to. Naturally, those skilled in the art will strive to utilize concurrent cofeeds with as little nonconcurrence as possible. Likewise, those skilled in the art will of course seek to maintain the cofeeds continuously with as few interruptions as possible under the given circumstances in which the operation is being conducted. [0048] It is to be understood that the reactants and components referred to by chemical name or formula anywhere in this document, whether referred to in the singular or plural, are identified as they exist prior to coming into contact with another substance referred to by chemical name or chemical type (e.g., another reactant, a solvent, or etc.). It matters not what chemical changes, transformations and/or reactions, if any, take place in the resulting mixture or solution or reaction medium as such changes, transformations and/or reactions are the natural result of bringing the specified reactants and/or components together under the conditions called for pursuant to this disclosure. Thus the reactants and components are identified as ingredients to be brought together in connection with performing a desired chemical operation or reaction or in forming a mixture to be used in conducting a desired operation or reaction. Also, even though an embodiment may refer to substances, components and/or ingredients in the present tense ("is comprised of", "comprises", "is", etc.), the reference is to the substance, component or ingredient as it existed at the time just before it was first contacted, blended or mixed with one or more other substances, components and/or ingredients in accordance with the present disclosure.

[0049] Also, even though the claims may refer to substances in the present tense (e.g.,

"comprises", "is", etc.), the reference is to the substance as it exists at the time just before it is first contacted, blended or mixed with one or more other substances in accordance with the present disclosure.

[0050] Except as may be expressly otherwise indicated, the article "a" or "an" if and as used herein is not intended to limit, and should not be construed as limiting, the description or a claim to a single element to which the article refers. Rather, the article "a" or "an" if and as used herein is intended to cover one or more such elements, unless the text expressly indicates otherwise.

[0051] Each and every patent or other publication or published document referred to in any portion of this specification is incorporated in toto into this disclosure by reference, as if fully set forth herein.

[0052] This invention is susceptible to considerable variation within the spirit and scope of the appended claims.

Claims

1. A process of preparing reaction-derived decahalodiphenyl oxide of high purity, which process comprises cofeeding separate feeds of

(a) diphenyl oxide and/or partially brominated diphenyl oxide and

2. A process as in Claim 1 wherein (a) is diphenyl oxide.

3. A process as in Claim 1 wherein (b) is bromine chloride or bromine chloride and bromine.

4. A process as in Claim 1 wherein (a) is diphenyl oxide, and wherein (b) is bromine chloride or bromine chloride and bromine.

5. A process as in Claim 1 wherein said process is conducted at atmospheric pressure.

6. A process as in Claim 1 wherein said feeding is subsurface to the liquid mixture.

7. A process as in Claim 1 wherein said process is conducted at atmospheric pressure, and wherein said feeding is subsurface to the liquid mixture.

8. A process as in Claim 1 wherein (a) is diphenyl oxide, wherein (b) is bromine chloride or bromine chloride and bromine, and wherein said feeding is subsurface to the liquid mixture.

9. A process as in Claim 1 wherein (b) is in an amount of about 30% to about 130% relative to the amount theoretically needed to perhalogenate (a).

10. A process as in Claim 1 wherein (a) is diphenyl oxide, wherein (b) is bromine chloride or bromine chloride and bromine, wherein said feeding is subsurface to the liquid mixture, and wherein (b) is in an amount of about 50% to about 115% relative to the amount theoretically needed to perhalogenate (a).

11. A reaction-derived product containing (i) at least 96% decabromodiphenyl oxide, (ii) nonabromodiphenyl oxide in an amount not exceeding 0.5%, and (iii) nonabromochlorodiphenyl oxide in an amount of about 0.1% to about 3%.

12. A flammable macromolecular material containing a flame retardant amount of a reaction-derived product of Claim 11.

13. A material as in Claim 12 wherein the macromolecular material is a thermoplastic polymer, a thermoset polymer, or a latex-based coating.