FR2532316A1 - HALOGENATED PHOSPHONIC BENZYL ESTERS, THEIR MANUFACTURING METHOD AND THEIR APPLICATION AS FLAME RETARDANTS - Google Patents

Abstract

NEW PHOSPHONATES OF FORMULA (DRAWING CF IN BOPI) IN WHICH X REPRESENTS A CHLORINE OR BROMINE ATOM R REPRESENTS A RADICAL ALKYL OF 1 TO 4 CARBON ATOMS M REPRESENTS THE AVERAGE NUMBER OF ATOMESX SUBSTITUTING THE AROMATIC CORE 0 AND IS COMPRISED AND 5. PROCESS FOR MANUFACTURING PHOSPHONATES BY CONDENSATION OF ONE OR MORE BENZYL HALOGENIDES WITH A 2 HALOGENO ALKOXY 1-3-2 DIOXAPHOSPHOLANE. THE NEW PHOSPHONATES CAN BE USED TO FIRE PLASTIC MATERIALS (FOR EXAMPLE POLYURETHANE FOAMS), ARTIFICIAL TEXTILES, ELASTOMERS, ETC ...

Description

The present invention relates to benzyl phosphonic esters

  halogenated, their preferred method of manufacture and

  their application in the inflamation of inflammatory materials

  ble. A large number of organic compounds containing phosphorus and chlorine or bromine have been proposed in the past as nonfunctional flame retardant additives for plastics, synthetic fibers and various

  other flammable materials Only a few have

naked an industrial realization.

  The best known and probably the oldest is the

  tris (2-chloro-ethyl) phosphate PO (OCH 2 CH 2 Cl) 3.

  It is also possible to mention tris phosphate (chlorine

isopropyl) PO 1 OCH (CH 2 Cl) CH 3.

  Phosphonates, for example bis (2chloroethyl) 2-chloro-ethyl phosphonate C 1 CH 2 CH 2 -PO (OCH 2 CH 2 Ci) 2

  pure or partially polycondensed, have also been commercially

in the same goal.

  All these compounds are easily accessible, but

  the disadvantage of being too volatile and too fluid, which often causes the storage of evaporation losses

  or migration and insufficient permanence of the fire effect.

  fugeant. Higher molecular weight compounds have been proposed to overcome this disadvantage, for example tetrakis (2-chloroethyl) ethylene diphosphate (CH 2 CH 2 0) 2 P (O) -OCH 2 CH However, such a compound as well as other similar compounds are somewhat too soluble in water and / or hydrolyzable, which again is

  detrimental to the permanence of the flame retardant effect.

  Derivatives of 2,2-bis (chloromethyl) -1,3-propane diol escaping the above criticism have also been

  proposed, for example diphosphate (Cl CH 2 CH 0) P (O) -OCH 2

  C (CH 2 C) 2 -CH 2 O (P) O (OCH 2 CH 2 C) 2, but such composites posen C (C 2 i) H 2 -P () OC 2 C 2 Ci 2 'but such Compounds often pose problems in the implementation; for example, in the flame retardancy of polyurethane foams, their too high viscosity makes it difficult for them to be applied by

metering pump.

  Brominated phosphates such as tris (2-3-dibromo-1-propyl) phosphate PO (OCH 2 CH Br CH 2 Br) 3, or chlorobromous such as tris phosphate (1bromo, 3-chloro, 2-propyl)

  PO 10CH (CH 2 Ci) CH 2 Brl 3 have also been proposed or used.

  but these were abandoned when it was recognized

  that they were endowed with carcinogenic properties.

  The halogenated benzyl phosphonates which are the subject of

  The present invention is partially described in US Pat. No. 3,547,842 to "American Cyanamid Company". They largely escape previous criticisms and meet the formula (I) X m.

CH 2 P ORX ()

0 CH -CH X

  in which X represents a chlorine or bromine atom R represents an alkyl radical of 1 to 4 atoms

of carbon.

  The average number m of atoms X substituents of the aromatic ring is between 0 and 5 The position-of the atoms

  chlorine or bromine on the benzene ring is indifferently

  ortho, meta or para. The invention also relates to

  mixtures of two or more phosphonates in the form of

mule (I).

  Phosphonates described in US Patent

  mentioned above are synthesized by the so-called

  Arbuzov between a benzyl halide and a phosphite of 3-trialkyl according to the reaction: * R: R

R 2

  CH 2 X + P (OR 1) 3 CH 2 OR 1) + R 1 X

II O

  But this path simultaneously gives other

  Phosphorus compounds, in particular the phosphonate R 1 P (OR 1) 2, i O and subproduces a halogenated hydrocarbon and the yield of the product of the invention is not very high Furthermore, this route does not allow to obtain the compounds of the invention such that the two ORX groups of the formula (I) are different A preferred method, also subject of the invention, consists in reacting a cyclic phosphite of ethylene (II-) with a benzyl halide (III) to -emperatures from 80 to 2000 C. (i>) X mxx O 'm CHO It m 2 CPORX Q CH-P-ORX

CH 2 X + 2

C 2 O-CH 2 -CH X

2 2

(III 1) (II)

  im) (i It was found in fact unexpectedly, that

  MICHAELIS-ARBUZOV condensation of chlorides and bromine

  Benzyl (III) resins with cyclic phosphites (II) occurred selectively with ring opening-according to the equation

  (1), that is to say without appreciable participation in the reaction

  (2) which seemed a priori also possible:

(2) X I OCH 2

m -

(III) + (II) A Q 2 H - + XRX

OCH (IV)

  The competing reaction (2) was highly inde-

  on the one hand because it would have by-produced a hydro-

  dihalogenated carbide, with lowering of the weight yield of MICHAELIS-ARBUZOV condensation and unnecessary loss in the final product of two halogen atoms, which are useful for the flame retardant activity sought; on the other hand because a cyclic phosphonate of ethylene such as (IV) is in general

  extremely sensitive to hydrolysis.

  The cyclic phosphite (II) can be obtained by one of the known conventional methods; for example by condensing a molecule of alkylene oxide with a molecule of chloro or bromo phosphite of cyclic ethylene (V) (also called 2-halogeno 1,3,2-dioxaphospholane), itself directly accessible through reaction of trichloride or phosphorus tribromide with glycol:

CH O + CH 2 CH R '

2 HX 2 \ O O

(3) PX 3 + HOCH 2 CH 20 H P-X (II)

CH 2 (V)

R 'being H, CH 3, C 2 H 5.

  Benzyl halides (III) involved in

  reaction (1) can be easily obtained by

  tion or bromination of toluene with or without a

  distillation is preferred. Preference is given to halogens

  nures (III) for which m is between 1 and 3 o Even

  the benzyl halides (III) used to

  to contain, as impure inert but not embarrassing,

  up to 5% polyhalogeno toluenes.

  New halogenated benzylphosphonates objects

  of the invention can be used as flame retardant

  in a large number of plastics such as polyurethanes, polystyrene, ABS, vinyl resins, epoxy resins, in elastomers, synthetic textile fibers,

  such as polyester, polyamide, acrylic fibers or

  crylics, used alone or in combination with other synthetic or natural fibers, in paints,

  adhesives or other combustible materials that it may be

  to protect against the risk of fire.

  The flame retardant properties of these products are

  particularly interesting in polyurethane foams.

  thanes with a remarkable permanence of flame retardant effect

  highlighted when carrying out aging tests

accelerated.

EXAMPLE 1

  In a balloon, 1,180 parts of trichlo-

  phosphorus solution is introduced in 2 hours at room temperature

  462 μl of ethylene glycol is allowed to react for 2 hours, then

  distilled under a vacuum of 2 399.80 Pa at 501 C the 2-chloro 1,3,2-

  dioxaphospholane; we collect 563 p; we charge this

  0.2 g of aluminum isopropoxide is added to the reaction flask and then 220 g of ethylene oxide are gradually added and the mixture is cooled to 20 ° -30 ° C. and distilled under a vacuum of 133.32 Pa at 570 ° C. (2-chloroethoxy) 1,3,2-dioxaphospholaneo 550 g is collected. This product is loaded into a flask and 592 g are added.

  of dichlorobenzyl chloride (a mixture of isomers

  2-4, 2-5 and 3-4) Heated for 16 hours at 160 ° C. A liquid is obtained whose acidity is 0.05 equivalents per kg.

  treated with 18 μ of ethyl orthoformate at 120 ° C. for 30 minutes.

  The mixture is sprayed at 160 OC under 1999.83 Pa.

  11% of a clear liquid consisting of bis (2-

  chloroethyl) dichlorobenzyl phosphonate.

  acidity: 0.01 equivalents per kg, refractive index n D = 1.5395 (cl) 2 O CH 2 CH Cl x

NMR: 2

  CH 2 CH 2 Cl b c H: 6.97 7.42 (H); 3.43 (Ha); 4.25 (Hb) and 3.65 ppm a (Hr 13: 30.0 30.5 (Ca), 65.7 (Cb) and 42.75 ppm (Cc) C

External reference Si (CH 3) 4.

EXAMPLE 2

We load in a balloon:

317 μl of phosphorus trichloride.

  Introduced in 2 hours at room temperature

124 μl of ethylene glycol.

  It is allowed to react for 2 hours, 0.06 p of aluminum isopropoxide is added.

  then gradually 86% ethylene oxide in cooling

between 20 and 30 C.

Then add

  305 μl of dichlorobenzyl chloride (mixture of isomers).

  It is heated for 14 hours at 160 ° C. It is allowed to cool to 120 ° C. It is treated with 10 μl of ethyl orthoformate for 30 minutes. The product obtained is then heated at 160 ° C. under 1399.83 Pa.

  600 p of a clear liquid consisting for the most part of the

from example 1.

-7-

EXAMPLE 3

  Flexible polyurethane foam blocks are prepared by using the following formulation: polyol UGIPOL 1120 (molecular weight triol-4,000 ry) water amine catalyst (N, N-dimethyl ethanolamine) metal catalyst (based on stannous octoate) commercial silicone surfactant additive flame retardant toluene diisocyanate LILENE T 80 (index 106) 00 parts 3,5 'e

0.30 "

  The density of the blocks obtained in free expansion is about 30 kg / m 3.

  The reaction to fire of foams is evaluated at

  yen conventional laboratory tests following measurement of oxygen index standard-NFT 51 071 standard horizontal combustion test- ASTM D 16927 T 4

  The measurement of the oxygen index consists in determining

  -miner, on a vertical test tube of section 12.5 x 12.5 mm, the minimum oxygen concentration of an oxygen + nitrogen mixture, allowing the maintenance of combustion during a

  lasting at least 3 minutes (or 75 mm in length).

  It is recognized that the improvement of the reaction to fire is even more important than the value of the index

oxygen is higher.

  * ASTM D 1692-74 provides for exposure to the

  a gas flame, the end of a horizontal test tube

  zontale (dimensions 50 x 150 x 13 mm) supported by a wire mesh, for a period of 30 seconds The test consists of 8 - measuring the length destroyed by the combustion (at maximum up to a mark located at 127 mm from the exposed end) and the duration of the combustion If the combustion stops spontaneously before the complete destruction of the specimen, and on 5 test pieces, the material is classified as self-extinguishing ("self-extinguishing").

  extinguishing "5 E) under the conditions of the test.

  The fire reaction tests are carried out before and after accelerated aging of the test pieces (in the enclosure

  at 90 ° C., 90% relative humidity for 5 or 24 hours).

  The products of Examples 1 and 2 are evaluated together

  two flame retardant additives available commercially

cially:

  one based on esters of 2-chloroethyl

  phosphonic acid (ANTIBLAZE 7 B from MOBIL CHEMICAL),

  the other constituted by the phosphate of tris (2-

chloroethyl) or TCEP.

  The overall results are given in the table

  next Accelerated aging tests include

  particularly highlight the benefits of the products of the

  vention (permanence of the flame retardant effect).

  Without aging Aging 5 H Aging 24 h

ADDITIVE

  Index Standard ASTM D 1692 Index Standard ASTM D 1692 Index Standard ASTM D 1692 Oxygen Oxygen Oxygen Rating i Rank to 1 Rank Witness 17.1 56 127 Burn 18.6 72 127 Br Ole 17.8 89 127 br Ole Example 1 22.7 36 42 SE 23.3 40 40 SE 23.2 42 42 SE Example 2 23.1 42 40 SE 23.0 34 41 SE 23.7 35 44 SE Antiblaze 78 22.6 40 44 SE 22 , 6 47 57 SE 22.2 76 127 br Ole TCEP 21.6 53 55 SE 21.0 117 127 br Ole 21.0 78 127 brel t = time of 1 = average combustion length in seconds br Average oil in mm (destruction total 127 average values over mm) 5 test pieces L Jn ON I% MI -

Claims (1)

New halogenated benzylphosphonates having the formula (I) wherein X represents a chlorine or bromine atom R represents an alkyl radical of 1 to 4 carbon atoms m represents the average number of substituent X atoms of the aromatic ring and is between 0 and 5. 2 Phodphonates according to claim 1, wherein ma is 1, 2 or 3. Phosphonates according to claim 1, wherein ma is 2. Phosphonates according to claim 1, wherein X is chlorine. Phosphonates according to claim 1, in which E R is CH 2 CH 2 -. Mixtures of two or more phosphonates according to Claims 1 to 5. Process for the production of the phosphonates according to Claims 1 and 6, in which one or more benzyl halides C 6 H 5 X CH 2 X are reacted. with the 6 '5-M m 2 cyclic phosphite of formula (II) CH O | P_ O RX. CH -0 (II) 8 Application of the phosphonates according to claims 1 to 6 to the flame retardancy of different synthetic materials: plastics, thermosets, elastomers, textiles. Application of phosphonates according to the claims   1 to 6-flame retardant polyurethane foams