EP1263866A1

EP1263866A1 - Use of bridged halogenated aryl phosphates as flameproofing agents

Info

Publication number: EP1263866A1
Application number: EP01911544A
Authority: EP
Inventors: Manfred Pieroth; Ottfried Schlak; Gert Jabs
Original assignee: Bayer AG
Current assignee: Bayer AG
Priority date: 2000-02-10
Filing date: 2001-01-29
Publication date: 2002-12-11
Also published as: DE10005768A1; AU2001240553A1; WO2001059001A1

Abstract

The invention relates to the use of bridged, halogenated aryl phosphates as flameproofing agents and to their use in plastics.

Description

Use of bridged halogenated aryl phosphates as flame retardants

The use of phosphorus-containing flame retardants in the production of plastics based on isocyanate, preferably polyurethane plastics including hard and calibration foams, has long been known in the art. Frequently used flame retardants are, for example, trischloroisopropyl phosphate (TCPP) or diphenyl cresyl phosphate (DKP).

Halogen-free phosphate esters such as DKP are often inadequate in their flame retardancy and have to be dosed high, including the mechanical properties of the foams, e.g. the compression hardness suffers.

TCPP has a good flame retardant effect, but migrates easily from the open-cell soft foams due to its high vapor pressure. As a result, it is not possible to use the TCPP in applications with low fogging requirements, for example in the automotive sector.

The use of solid flame retardants such as ammonium polyphosphate has therefore been proposed. However, powdered flame retardants are difficult to incorporate into the often highly viscous starting materials of the polyurethane plastics. In addition, they have to be dosed at a relatively high level and thereby reduce the elongation at break of the foams due to their notch effect, particularly in the case of soft foams.

Accordingly, a liquid flame retardant with a good effect is advantageous, which has a low tendency to migrate, in particular from the open-celled polyurethane flexible foams.

It has now surprisingly been found that tetrakis-haloalkyl-arylene-diphosphate esters of the general formula (I) wherein

Ar for an optionally substituted arylene radical,

n stands for a numerical value between 0.9 and 2,

R represents an optionally substituted alkylene radical, preferably isopropylidene or ethylene, and

Shark represents halogen, preferably chlorine or bromine,

in addition to having a sufficient flame retardancy, also have a low tendency to migrate out of polyurethane plastics.

Preferred compounds of formula (I) are those in which

Ar represents an optionally substituted C 1 -C 4 -arylene radical, for example

n stands for a numerical value between 0.9 and 2.

R for an optionally substituted unbranched or branched

Ci-Cg-alkylene is such as methylene. Ethylene -CH ₂ -CH ₂ -.

Propane-1,3-diyl, isopropylidene , Butane-1,4-diyl,

Isobutane-l, 3-diyl, pentane-l, 5-diyl, isopentane-l, 4-diyl, hexane-1,6-diyl and

Shark represents halogen, preferably chlorine or bromine.

Particularly preferred tetrakis-haloalkyl-arylene diphosphate esters are compounds of the general formula (I)

wherein

stands,

n stands for a numerical value between 0.9 and 2, R for propane-1, 3-diyl or iso-propylidene stands and

Shark stands for chlorine.

Particularly preferred bridged and halogenated aryl phosphate esters according to the present invention are the tetrakis chloropropyl ester of 1,3-phenylene diphosphate (TC-RDP) and the tetrakis chloropropyl ester of bisphenol A diphosphate (TC-BDP), which are used in the Implementation of the corresponding tetrachlorophosphoric diester can be obtained with propylene oxide, resulting in a mixture of tetrakis chloroisopropyl esters and tetrakis chloro-n-propyl esters with a higher proportion of tetrakis chloroisopropyl esters.

Tetrakisphosphonic chlorisopropyl bisphenol A diphosphate

Tetrakis chloroisopropyl 1,3 phenylene diphosphate Tetrakis-haloalkyl-arylene-diphosphate esters have already been used for other purposes. For example, DE-A 2 122 773 describes, among other things, the use of tetrakis-chloroisopropyl-1,3-phenylene diphosphate as an adhesion promoter in composite rubber articles.

Production processes for the compounds of the general formula (I) to be used according to the invention are also known in principle. They can be obtained analogously to the preparation of the trischloroisopropylene phosphate by reacting the corresponding tetrachlorophosphoric diester with propylene oxide in the presence of catalysts. A description of the manufacturing process can be found, for example, in Chapter 1.9 of the IUCLID (International Chemical Information Database). Due to the manufacturing process, oligomeric fractions corresponding to n> 1 are unavoidable.

The compounds of general formula (I) to be used according to the invention are preferably used in amounts of 1 to 20% by weight, based on the plastic, preferably isocyanate-based plastics.

The production of isocyanate-based plastics is known and is described, for example, in German Offenlegungsschrift DE-A 44 18 307

References described. The content of DE-A 44 18 307 is included in the present application.

The plastics based on isocyanate are predominantly plastics containing urethane and / or isocyanurate and / or allophanate and / or uretdione and / or urea and / or carbodiimide groups. The compounds of the general formula (I) to be used according to the invention are preferably used in the production of polyurethane, soft and rigid foams.

The following are used to manufacture the isocyanate-based plastics: A.) As starting components ahphatic, cycloaliphatic, araliphatic, aromatic and heterocychic polyisocyanates, as are described, for example, in DE-A 44 18 307, for example those of the general formula (II)

Q (NCO) _m (II)

in the

m represents an integer from 2 to 4, preferably from 2 to 3, and

Q for an aliphatic hydrocarbon residue with 2 to 18 C atoms, preferably with 6 to 10 C atoms, or for a cycloaliphatic hydrocarbon residue with 4 to 15 C atoms, preferably 5 to 10 C atoms, or for an aromatic hydrocarbon residue with 6 to 15 carbon atoms, preferably 6 to 13 carbon atoms or an araliphatic hydrocarbon radical with 8 to 15 carbon atoms, preferably 8 to 13 carbon atoms. For example, such polyisocyanates are used as are described in DE-A 28 32 253, pages 10 to 11.

The technically easily accessible polyisocyanates, for example the 2,4- and 2,6-tolylene diisocyanate (TDI), and any mixtures of these isomers ("TDI"), polyphenylpolymethylene polyisocyanates ("MDI") are generally used with particular preference. as they are produced by aniline-formaldehyde condensation and subsequent phosgenation. Also crude MDI and carbodiimide groups, urethane groups, allophanate groups, isocyanurate groups, urea groups or biuret groups containing polyisocyanates ("modified polyisocyanates"), in particular those modified polyisocyanates which differ from 2,4- and / or 2,6- Toluene diisocyanate or derived from 4,4'- and / or 2,4'-diphenylmethane diisocyanate can be used.

B.) Starting components are also compounds having at least two isocyanate-reactive hydrogen atoms with a molecular weight of generally from 400 to 10,000.

In addition to amino groups, thio groups or compounds having carboxyl groups, this is understood to mean compounds having hydroxyl groups, in particular 2 to 8 hydroxyl groups

Compounds, especially those of molecular weight 1,000 to 6,000, preferably 2,000 to 6,000, e.g. at least 2, usually 2 to 8, but preferably 2 to 6, hydroxyl-containing polyethers or polyesters and polycarbonates or polyester amides, as are known for the production of homogeneous and cellular polyurethanes and as described, for example, in DE-A 28 32 253, pages 11 to 18.

C.) If appropriate, compounds with at least two isocyanate-reactive hydrogen atoms and a molecular weight of 32 to 399 can be used as additional starting components. In this case too, this means compounds containing hydroxyl groups and / or amino groups and / or thiol groups and / or carboxyl groups, preferably compounds containing hydroxyl groups and / or amino groups, which serve as chain extenders or crosslinking agents.

These compounds generally have 2 to 8, preferably 2 to 4, hydrogen atoms which are reactive toward isocyanates. Examples of this are described in DE-A 28 32 253, pages 19 to 20.

D.) If necessary, auxiliaries and additives are used as well a) water and / or volatile organic substances such as pentane or cyclopentane as blowing agents,

b) additional catalysts of the known type in amounts of up to

10% by weight, based on the amounts of starting components as mentioned under B.),

c) surface-active additives, such as emulsifiers or foam stabilizers,

d) reaction retarders, for example acidic substances such as hydrochloric acid or organic acid halides, further cell regulators of the known type such as paraffins or fatty alcohols or dimethylpolysiloxanes as well as pigments or dyes and other flame retardants of the known type, for example tricresyl phosphate, diphenylcresyl phosphate, melamine, ammonium polyphosphate, red phosphorus,

e) furthermore stabilizers against aging and weather influences,

Plasticizers and fungistatic and bacteriostatic substances as well as fillers such as barium sulfate, diatomaceous earth, soot or sludge chalk.

These auxiliary substances and additives, which may also be used, are described, for example, in DE-A 27 32 292, pages 21 to 24.

References to further references for examples of surface-active additives and foam stabilizers which may also be used according to the invention, and cell regulators, reaction retarders, stabilizers, flame-retardant substances, plasticizers, dyes and fillers, and fungistatic and Bacteriostatically active substances and details of the use and mode of action of these additives can also be found in DE-A 44 18 307.

The production of isocyanate-based plastics is known. In the production of polyurethane plastics, for example, the reaction components are reacted according to the known one-step process, the prepolymer process or the semi-prepolymer process, machine equipment often being used, for example those described in US Pat. No. 2,764,565.

Corresponding references are also given in DE-A 44 18 307 for details about processing devices which are suitable according to the invention.

Of course, foams can also be produced by block foaming or by the known foam molding process.

The tetrakis-haloalkyl-arylene-diphosphate esters can generally be used in plastics to reduce flammability. They are preferably used in polyurethane plastics or in polyurethane foams. The tetrakis haloalkyl arylene disphosphate esters are therefore particularly suitable for use as upholstery material in the automotive and residential sectors. Rigid foams with the products to be used according to the invention can also be used, for example, as insulation and insulation material in the construction sector.

For the purposes of this invention, it is not only possible to use compounds of the general formula (I) alone but also in a mixture with other flame retardants in plastics. The present invention therefore also relates to flame retardants which, in addition to other flame retardants, contain an effective proportion of tetrakis-halogenoalkyl-arylene-diphosphate esters in plastics and significantly reduce their flammability. Examples

Flexible polyurethane foams were produced according to the formulations described below both with the tetrakis-halogeno-alkyl-arylene-phosphate esters of the general formula (I) to be used according to the invention, such as the known trischloroisopropyl phosphate, and compared them in terms of fire behavior and migration rate :

As a result, with a dosage of the compounds according to the invention that was less than the equivalent weight of the TCPP used, an equally good flame retardant effect is achieved with surprisingly significantly lower fogging values.

Claims

claims

1. Use of tetrakis-haloalkyl-arylene-diphosphate esters of the general formula (I)

in which

n stands for a numerical value between 0.9 and 2,

Ar represents an optionally substituted arylene radical,

R represents an optionally substituted alkylene radical and

Shark represents halogen,

as a flame retardant in the manufacture of plastics.

2. Use according to Anspmch 1, characterized in that tetrakis chloropropyl 1,3-phenylene diphosphate is used.

3. Use according to Anspmch 1, characterized in that tetrakis chloropropyl bisphenol A diphosphate is used.

4. Use of tetrakis-haloalkyl-arylene diphosphate esters of the general formula (I) according to Claim 1 as flame retardants in the production of plastics based on isocyanate.

5. Use according to Anspmch 4, characterized in that the compounds of general formula (I) are used in amounts of 2 to 20% by weight, based on the isocyanate-based plastic.

6. Process for reducing the flammability of plastics, characterized in that compounds of the general formula (I) according to

Claim 1 uses.

7. The method according to Anspmch 6, characterized in that the plastics are polyurethane plastics or polyurethane foams.

8. Use of tetrakis-haloalkyl-arylene diphosphate esters of the general formula (I) according to Claim 1 for the production of flame-retardant plastics as upholstery material for the automotive and residential sectors.

9. Use of tetrakis-haloalkyl-arylene diphosphate esters of the general formula (I) according to Claim 1 for the production of rigid foams as insulating and insulating material in the construction sector.

10. Plastics containing an effective proportion of tetrakis haloalkyl arylene diphosphate esters to reduce flammability.

11. Plastics containing, in addition to other flame retardants, an effective proportion of tetrakis-halogenoalkyl-arylene-diphosphate esters according to formula (I) in Claim 1.