FR2532317A1 - NOVEL HALOGENATED BENZYL PHOSPHONIC ESTERS, THEIR MANUFACTURING METHOD AND THEIR APPLICATION AS FLAME RETARDANTS - Google Patents

Abstract

NEW PHOSPHONATES OF FORMULA (CF DRAWING IN BOPI) IN WHICH X REPRESENTS A CHLORINE OR BROMINE ATOM M AND N REPRESENT THE AVERAGE NUMBERS OF X ATOMS SUBSTITUTE OF THE AROMATIC NUCES AND ARE INCLUDED BETWEEN 0 AND 5. PROCESS FOR MANUFACTURING THE PHOSPHONATES CONDENSATION OF ONE OR MORE BENZYL HALOGENIDES WITH 2,2 '1,2 ETHANE DIYL BIS (1,3,2 DIOXAPHOSPHOLANE). THE NEW PHOSPHONATES CAN BE USED TO FIRE PLASTIC MATERIALS (FOR EXAMPLE POLYURETHANE FOAMS), ARTIFICIAL TEXTILES, ELASTOMERS, ETC ...

Description

1 - The present invention relates to new esters

  halogenated benzyl phosphonic compounds, their pre-

  and their application in the intignation of

  flammable. 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

  very flammable materials Only a few have known

an industrial realization.

  The best known and probably the oldest is the

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

2 2 3

  Tris phosphate (chlorine) may also be mentioned

  isopropyl) PO 10CH (CH 2 Cl) CH 313.

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

  pure or partially polycondensed, have also been

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 (Cl CH CH 0) P (O) OCH 2 CH 2 O P (O) ( OCH 2 CH 2 Ci) 2 but such a compound, as well as other analogous compounds are a little too soluble in water and / or hydrolysable, 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 CHO) P (O) OCH -

222 2

  -2 - C (CH 2 C 1) 2 CH 2 O (O) OCH 2 CH 2 Cl) 2, but such compounds often pose problems in the implementation; for example in the flameproofing of polyurethane foams, their too high viscosity makes it difficult for them to be operated 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 have been abandoned when it was recognized

  that they were endowed with carcinogenic properties.

  The new halogenated benzyl phosphonates which are the subject of the present invention largely escape criticism

  and are particularly distinguished by the perma-

  These phosphonates correspond to formula (I),

X O O X

  Xm il il m CH 2 P OCH-CH-O P CH 2 (I)

I 2 2

0 CH-CH X 0-CH CH X

2 2 2 2

  wherein X represents a chlorine or bromine atom.

  The average numbers m and N identical to or different from the substituent X atoms of the aromatic rings are between 0 and 5. The position of the chlorine or bromine atoms on the (or) ring (s) benzene (s) is indifferently ortho, meta or para The invention also relates to mixtures of

  two or more phosphonates corresponding to formula (I).

  The preferred method of preparing these phosphonates

  ts, also subject of the invention, consists in reacting the cyclic diphosphite of ethylene (II) with one or

25323 17

  several benzyl halides (III) at temperatures

from 80 to 200 C.

(1) o X m

\ ^ <CH 2

(III) X n

X + CH 2 X

{II) 2

(III)

CH -O 0-CH

2 / i 2

+, P-OCH 2-CH 2-0-P 2

CH 20 0-CH

(2b 2) (II) x m

\ Q> CH 2 -P OCHCH -0

2 2 2

OCH 2 CH 2 X

P CH

O 1 C 2

CH -CH

  It was unexpectedly found that the MICHAELIS-ARBUZOV condensation of chlorides and benzyl bromides (III) with cyclic phosphite (II) occurred selectively with opening of the ring according to equation (1).

  that is, without appreciable participation in the reaction

  currente (2), which seemed a priori also possible

ble: m m 10 OCH

CH 2 P |

OCH (IV):

+ X-CH 2-CH 2-X

  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 Xn * n (2) X

2 (III) + (II) -2

  4 - the condensation of MICHAELIS-ARBUZOV and unnecessary loss in the final product of two halogen atoms, very useful for the flame retardant activity sought; on the other hand because a cyclic ethylene phosphonate such as (IV) is generally extremely sensitive to hydrolysis. The cyclic diphosphite (II) can be synthesized, for example by transesterifying two molecules of triethyl or triphenyl phosphite by three molecules of ethylene glycol or by reacting 2 molecules of 2-halogeno-1,3,2

  dioxaphospholane with an ethylene glycol molecule

  the presence of two tertiary amine molecules.

  Benzyl halides (III) involved in

  reaction (1) can easily be obtained by

  tion or bromination of toluene, whether or not followed by

  distillation is preferred. Preference is given to halogens

  Nures (III) for which m or N are between 1 and 3.

  Optionally, the benzyl halides (III) used may contain, as an inert impurity but not a nuisance,

  up to 5% polyhalogeno toluenes.

  The new halogenated benzylphosphonates which are the subject of the invention can be used as flame retardant additives

  in a large number of plastics such as poly-

  urethanes, polystyrene, ABS, vinyl resins, epoxy resins, in elastomers, synthetic textile fibers,

  such as polyester, polyamide, acrylic fibers or

  crylics, alone or in combination with other

  synthetic or natural paints, paints,

  or other combustible materials that it may be desirable

  protect against the risk of fire.

  * 30 The flame retardant properties of these products are

  particularly interesting in polyurethane foams.

  born with a remarkable permanence of flame retardant effect

  highlighted when carrying out aging tests

accelerated.

EXAMPLE 1

  310 μl of triphenyl phosphite (93 μl) of ethylene glycol (0.25 μ) of sodium methoxide are charged into a flask. The mixture is heated for 1 hour 30 minutes at 150 ° C.

  the phenol produced by transesterifica-

  and then the residue is distilled under a vacuum of 133.32 Pa at

  123 C is obtained 90 p of 2,2 'li, 2 ethane diyl bis (1,3,2

  dioxaphospholane) l This product is loaded into a flask,

  add 142 p of dichlorobenzyl chloride (isomeric mixture

  essentially 2-4, 2-5 and 3-4).

  1600 C; the mixture is heated to 1600 ° C. under 1999.83 Pa.

  holds 225 p of a neutral clear liquid corresponding to the

  the: (Cl) OCH CH Cl OCH-CH Cl (c) 2 O) 22 j 2 c 2 2 (21)

CH 2 O CH 2 CH 2 OCH Q

a I b I

O O O

  Refractive index N = 1.5565 D NMR: 1H: 3.39 (Ha); 4.20 (Hb, Hc) and 3.65 ppm (Hd) H 1 C: 30.2 B 30.77 (Ca); 65.14 66.55 (Cb, Cc) and C 42.9 ppm (Cd) External reference Si (CH 3) 4

EXAMPLE 2

  Charge in a flask as in Example 1: 310 p triphenyl phosphite 93 p ethylene glycol

0.25 μ of sodium methoxide.

  The phenol produced by transesterification was distilled under a vacuum of 1,999.83 Pa for 1 h 30 min. Dichlorobenzyl chloride (mixture of isomers) is added directly to the flask. The mixture is heated for 20 hours at 160 ° C. It is allowed to cool to C. It is treated with 15 μ of ethyl orthoformate for 1 min to neutralize the slight acidity of the product. The product obtained is then prilled at 160 ° C. under 1999.83 Pa. a clear liquid consisting for the most part of the product

of Example 1.

EXAMPLE 3

  Blocks of flexible polyurethane foam are prepared

  by the use of the following formulation: UGIPOL 1120 polyol (molecular weight triol 4,000) 100 parts water 3,5 "amine catalyst (N, N-dimethylethanolamine) 0.30" metal catalyst (d stannous octoate) 0.25 "commercial surfactant silicone 0.80" flame retardant additive 10 "toluene diisocyanate LILENE T 80 (index 106) 43" The density of the expanding blocks

free is about 30 kg / m.

  The reaction to fire of foams is evaluated at

  yen the following standard laboratory tests: Oxygen index measurement: NFT standard 51 071 horizontal combustion test: ASTM D 1692-74 7-

  The measurement of the oxygen index consists in determining

  net, on a vertical test tube 12.5 x 12.5 mm, the minimum oxygen concentration of a mixture of oxygen and nitrogen, allowing the maintenance of combustion for a period of at least 3 minutes (or on a length of 75 mm). It is recognized that improving 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 flame

  a gas turbine, the end of a horizontal test-tube

  (dimensions 50 x 150 x 13 mm) supported by a metallic cloth

  For a period of 30 seconds, the test consists of measuring the length destroyed by combustion (at maximum up to a mark 127 mm from the exposed end) and the duration of the combustion If combustion ceases spontaneously before the complete destruction of the specimen, and on 5 specimens, the material is classified auto = extinguishing ("Oself = extinguishing")

SE) under the conditions of the test.

  Reaction to fire tests are carried out before and after aging accelerate-specimens (in pregnant

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

  The products of Examples 1 and 2 are evaluated together

  in contrast to two flame retardant additives available

cially:

  one based on esters of 2-chloroethylphosphoric acid

  phonic (ANTIBLAZE 78 of MOBIL CHEMICAL),

  the other consisting of tris phosphate (2-chloro

roethyl) or TCEP.

  The overall results are given in the table

  next Accelerated aging tests are particularly

  firstly, the advantages of the products of the invention

  (permanence of the flame retardant effect).

  Without aging Aging 5 h Aging 24 h

INDEX

  Index Standard ASTM D 1692 Index Standard ASTM D 1692 Index Standard ASTM D 1692 FLAME RETARDANT Oxygen Oxygen F% At 1 Rank t 1 Rank t 1 Rank Witness 17.1 56 127 br Ole 18.6 72 127 br Ole 17, 8 89 127 br Ole Example 1 22.7 33 40 SE 23.8 34 40 SE 23.4 30 33 SE Example 2 23.0 35 44 SE 22.9 39 48 SE 23.4 37 47 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 br Ole i __ ,, iii t = tem Average Bps of combustion in seconds 1 = length br Average burnt in mm (destruction) average values over total 127 mm) 5 test pieces ll -9-

Claims (1)

1 New halogenated benzylphosphonates corresponding to the formula (I) wherein X represents a chlorine or bromine atom m and N, which are identical or different, represent the average numbers of Substitutent X atoms of the aromatic compounds and are from 0 to 5. 2 Phosphonates according to claim 1, wherein m and N are 1, 2 or 3. 3 Phosphonates according to claim 1, wherein -m and N have the value 2. 4. Phosphonates according to claim 1 wherein X represents a chlorine atom. Mixtures of two or more phosphonates according to Claims 1 to 4. Process for the production of the phosphonates according to Claims 1 and 5 in which one or more benzyl halides C 6 H 5 m X x CH 2 X and C 6 are reacted. ## STR1 ## 5 to the flame retardancy of various synthetic materials: plastics, thermosets, elastomers, textiles 8 Application of the phosphonates according to the claims   1 to 5 for the fireproofing of polyurethane foams.