Note: Descriptions are shown in the official language in which they were submitted.
1049030
The invention provides new 1,2-oxaphospholane-5-
phosphonic acid esters, a process for their manufacture, a
method of using them as flameproofing agents for thermoplastic
polymers, polyurethanes, epoxy resins, cellulose and cellulose
derivatives and also, as industrial product, the substrates
protected by them.
The new compounds have the general formula I
R6 7
~ C C - P ORl (I)
R4~1 1 OR2
R5 \ p /
o~! \ OR3
wherein Rl and R2 each represents alkyl with 1 to 18 carbon
: atoms, haloalkyl, alkoxy alkyl, having not more than 18 carbon
: atoms, alkenyl with 3 to 18 carbon atoms, cycloalkyl with 5 to
8 carbon atoms or tetrahydrofurfuryl, R3 represents alkyl with
1 to 8 carbon atoms, cycloalkyl with 5 to 8 carbon atoms, alkenyl
with 3 to 8 carbon atoms alkoxy alkyl with not more than 8
carbon atoms or tetrahydrofurfuryl, R4 represents hydrogen or
: methyl, R5 represents hydrogen, alkyl with 1 to 8 carbon atoms,
phenyl, methyl phenyl, methoxy phenyl or chlorophenyl or furyl,
R6 represents hydrogen or methyl, and R7 represents lower
`~ alkyl with 1 to 8 carbon atoms.
i
~i :
~L
qF
. ~.
~B 2 -
.
1049030
A monovalent aliphatic radical represented
by Rl, R2 or R3 can be a linear or branched alkyl
or alkenyl radical which is unsubstituted or
substituted by halogen or alkoxy groups. Examples
of such radicals are methyl, ethyl, isopropyl,
n-butyl, 2-ethylhexyl, isooctyl, n-dodecyl,
n-octadecyl, allyl, methallyl, oleyl, 2-chloro-
ethyl, 2-bromoethyl, 2,3-dibromopropyl, 2-ethoxy-
ethyl, 2-butoxyethyl or 2-methoxypropyl. Where
these same substituents represent a monovalent
cycloaliphatic or araliphatic radical, such a
radical can be, for example, cyclopentyl,
cyclohexyl, cyclooctyl, benzyl, phenylethyl or
4-chlorobenzyl.
Alkyl radicals represented by R5
or R7 can be linear or branched alkyl radicals,
~ e.g. methyl, ethyl, isopropyl, tert, butyl,
- n-hexyl, 2-ethylhexyl, n-octyl, isooctyl,
n-dodecyl or n-octadecyl. By halogen is
meant in this specification fluorine, chlorine
or bromine.
,
,
,:~ . :'
'~ ~
;'''
-- 3 --
B~
:
. . . ... . .. . ,.... ~ ..
. . . . . . . . . .. . .. .
1049030
Compounds of the formula I which
constitute a special class of these compounds
are thosewherein each of Rl and R2 independently
represents a monovalent aliphatic or cyclo-
aliphatic, R3 is the same as either Rl or R2,
each of R4 and R6 independently represents
hydrogen or methyl, R5 represents alkyl or
phenyl, methylphenyl, methoxyphenyl,
: chlorophenyl or furyl and R7 represents
. alkyl.
To this class of compounds belong
the compounds of the formula I wherein
`;( R3 is the same as either Rl or R2.
';
'"
..
,, ~:
.~'`"` .
~ '
:~`,. .
~, ,.
?
B~ ~ 4 ~
. ~ .
-,
: . - . . . . . .
104gO30
Particularly preferred compounds of
the formula I are those wherein Rl, R2 and R3
are identical and represent linear or branched
alkyl radical with 1 to 8 carbon atoms, alkoxy-
alkyl with 3 to 6 carbon atoms, chloroethyl,
bromoethyl, alkenyl with 3 to 4 carbon atoms,
cyclohexyl or benzyl, R4 represents hydrogen
or methyl, R5 represents hydrogen, methyl -
ethyl, phenyl, chlorinated phenyl or furyl,
R6 represents hydrogen, and R7 represents
methyl or ethyl.
. Examples of individual compounds of
~ the formula I are the following 1,2-oxaphospholane
i derivatives:
2-oxo-2-methoxy-5-methyl-S-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-ethoxy-5-methyl-5-diethylphosphono-1,2- i ~:
,~ oxaphospholane ~ '
2-oxo-2-iospropoxy-5-methyl-5-di-isopropylphosphono-
1,2-oxaphospholane
.'' `~
,;
~ '
" .
. _ 5 _
B~
.... . ~. . . ........ . .
.. . . . .
10490i~0
2-oxo-2-butoxy-5-methyl-5-dibutylphosphono-1,2-oxaphospholane
2-oxo-2-octoxy-5-methyl-5-dioctylphosphono-1,2-oxaphospholane
2-oxo-2-(2-ethyl-hexyloxy)-5-methyl-5-di-(2-ethylhexyl)-phosphono-
1,2-oxaphospholane
2-oxo-2-octadecyloxy-5-methyl-5-di-octadecylphosphono-1,2-oxaphos-
pholane
2-oxo-2-(2-chloroethyloxy)-5-methyl-5-di-(2-chloroethyl)-phosphono-
1,2-oxaphospholane
2-oxo-2-(2-methoxyethyloxy)-5-methyl-5-di-(2-methoxyethyl)-phosphono-
1,2-oxaphospholane
2-oxo-2-benzyloxy-5-methyl-5-di-benzylphosphono-1,2-oxaphospholane
2-oxo-2-(4-chlorobenzyloxy)-5-methyl-5-di-(4-chlorobenzyl)-phos-
:. phono-1,2-oxaphospholane
2-oxo-2-(4-bromobenzyloxy)-5-methyl-5-di-(4-bromobenzyl)-phosphono-
1,2-oxaphospholane
2-oxo-2-methoxy-5-ethyl-5-dimethylphosphono-1,2-oxaphospholane
2-oxo-2-ethoxy-5-ethyl-5-diethylphosphono-1,2-oxaphospholane
2-oxo-2-methoxy-5-phenyl-5-dimethylphosphono-1,2-oxaphospholane
2-oxo-2-ethoxy-5-phenyl-5-diethylphosphono-1,2-oxaphospholane
2-oxo-2-methoxy-3,5-dimethyl-5-dimethylphosphono-1,2-oxaphospholane
; 2-oxo-2-ethoxy-3,5-dimethyl-5-diethylphosphono-1,2-oxaphospholane
2-oxo-2-methoxy-3,4-dimethyl-5-dimethylphosphono-1,2-oxaphospholane
2-oxo-2-ethoxy-3,4-dimethyl-5-diethylphosphono-1,2-oxaphospholane
2-oxo-2-methoxy-3,3,5-trimethyl-5-dimethylphosphono-1,2-oxaphos-
pholane
2-oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphospholane
2-oxo-2-isopropoxy-3,3,5-trimethyl-5-di-isopropylphosphono-1,2-
oxaphospholane
2-oxo-2-butoxy-3,3,5-trimethyl-5-dibutylphosphono-1,2-oxaphospholane
2-oxo-2-(2-ethylhexyloxy)-3,3,5-trimethyl-5-di-(2-ethylhexyl)-
phosphono-1,2-oxaphospholane
2-oxo-2-(2-chloroethoxy)-3,3,5-trimethyl-5-di-(2-chloroethyl)-
- 6 -
1049030
phosphono-1,2-oxaphospholane
2-oxo-2-benzyloxy-3,3,5-trimethyl-5-dibenzylphosphono-1,2-oxaphos-
pholane
2-oxo-2-cyclohexyloxy-3,3,5-~rimethyl-5-dicyclohexylphosphono-1,2-
oxaphospholane
2-oxo-2-methoxy-3-phenyl-5-methyl-5-dimethylphosphono-1,2-oxaphos-
pholane
2-oxo-2-ethoxy-3-phenyl-5-methyl-5-diethylphosphono-1,2-oxaphos-
pholane
2-oxo-2-methoxy-3-(4-chlorophenyl)-5-methyl-5-dimethylphosphono-
1,2-oxaphospholane
; 2-oxo-2-methoxy-3-~4-bromophenyl)-5-methyl-5-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-methoxy-3-(4-methylbenzyl)-5-methyl-5-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-methoxy-3-(4-methoxyphenyl)-5-methyl-5-dimethylphosphono-
~ 1,2-oxaphospholane
2-oxo-2-methoxy-3-(furyl-2)-5-methyl-5-dimethylphosphono-1,2-
oxaphospholane :
2-oxo-2-methoxy-3-(thienyl-2)-5-methyl-5-dimethylphosphono-1,2-
. oxaphospholane
2-oxo-2-methoxy-3-(pyridyl-2)-5-methyl-5-dimethylphosphono-1,2-
. oxaphospholane
i 2-oxo-2-methoxy-3-methyl-5-phenyl-5-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-methoxy-3-methyl-5-(4-chlorophenyl)-5-dimethylphosphono-
1,2-oxaphospholane
2-oxo-2-methoxy-3,5-diphenyl-5-dimethylphosphono-1,2-oxaphospholane
~: 2-oxo-2-ethoxy-3,5-diphenyl-5-diethylphosphono-1,2-oxaphospholane
. 30 2-oxo-2-methoxy-3-(4-chlorophenyl)-5-phenyl-5-dimethylphosphono-
. 1,2-oxaphospholane
- 2-oxo-2-methoxy-3,5-di-(4-chlorophenyl)-5-dimethylphosphono-1,2-
.
.
~0490;~0
oxaphospholane
2-oxo-2-methoxy-3-phenyl-5-(4-chlorophenyl)-5-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-methoxy-3-(4-methylphenyl)-5-phenyl-5-dimethylphosphono-
1,2-oxaphospholane
2-oxo-2-methoxy-3-(4-methoxyphenyl)-5-phenyl-5-dimethyl-phosphone-
1,2-oxaphospholane
2-oxo-2-methoxy-3-phenyl-5-(4-methylphenyl)-5-dimethylphosphono-
1,2-oxaphospholane
2-oxo-2-methoxy-3-(phenyl-2)-5-phenyl-5-dimethylphosphono-1,2-
oxaphospholane
2-oxo-2-allyloxy-3,3,5-trimethyl-5-diallylphosphono-1,2-oxaphos-
pholane
2-oxo-2-tetrahydrofurfuryl-3,3-5-trimethyl-5-di-(tetrahydrofurfuryl)-
phosphono-(1,2-oxaphospholane)
The surprising discovery has been made that it is possible to manu-
facture the compounds of the formula I, in which R3 is the same as Rl or R2,
by a novel process which comprises reacting an a,~-unsaturated ketone of the
formula II
2Q 4 \ R6 (II)
R5
with atleast2 moles of a phosphite of the formula III
~0 /
H - P \ (III)
. OR2
in the presence of a base, with or without the addition of a solvent.
Examples of a,B-unsaturated ketones of the formula II are methyl
. .~
S vinyl ketone, ethyl vinyl ketone, phenyl vinyl ketone, mesityl oxide, methyl
isopropenyl ketone, benzalacetone, benzalacetophenone or 4-chlorobenzalace-
tone. Such ketones can be manufactured by known methods, for example by
condensation of the appropriate methyl ketones with aldehydes or ketones.
- 8 -
' ''
10'19030
The phosphites of the formula III are known compounds of industrial
availability. Examples thereof are dialkyl phosphites, e.g. dimethyl, di-
ethyl or dioctyl phosphite, dicycloalkyl phosphites, e.g. dicyclohexyl
phosphite, diaralkyl phosphites, e.g. dibenzyl phosphite, and mixed phos-
phites, e.g. methyl butyl phosphite, methyl benzyl phosphite or isopropyl
cyclohexyl phosphite.
In the reaction there are used 2 moles, preferably 205 to 3.5
moles, of a compound of the formula III for each mole of the compound of the
formula II.
Examples of bases which catalyse the reaction are principally
alkali metals, alkali metal or alkaline earth metal alkoxides, alkali metal
amides and hydrides. Particularly effective are the metals sodium and
potassium, sodium methoxide, potassium tert. butoxide, lithium amide and
calcium hydride; but the two metals are particularly suitablefor the purpose.
Normally, catalytic amounts of these bases suffice to initiate the reaction.
; It is sometimes advantageous to add further amounts of base during the reac-
tion.
If the process according to the invention is carried out with the
addition of a solvent, then suitable solvents are primarily hydrocarbons,
e.g. benzene, toluene, xylene, ligroin, hexane or heptane, also alcohols,
e.g. methanol, ethanol or isopropanol, or ethers, e.g. diethyl ether, dioxan
or tetrahydrofuran.
The reaction can be carried out by dissolving the ketone of the
formula II and adding dropwise a portion of the phosphite of the formula III
and the base. Upon onset of the reaction, the remainder of the phosphite and,
if necessary, further amounts of base, are addedby gradual amounts. It is
also possible to premix the phosphite with the catalyst and to add the ketone
of the formula II dropwise.
In another embodiment, the compounds of the formula II and III
and optionally the solvent are first mixed and then the base, which can also
be dissolved in the solvent, is added to this mixture and the reaction is
brought to completion by heating.
_ g _
1049030
The oxaphospholanes of the formula I are isolated by customary
methods, for example by distillation. Desirably the base is neutralised be-
fore the isolation by an equivalent amount of an acid, for example acetic
acid.
The reaction of dialkyl phosphites with a,B-unsaturated ketones
has already been thoroughly investigated by various experts. It has hitherto
been considered the rule that in the reaction only 1 mole of phosphite is
added to the double bond forming the y-ketophosphonates (see Houben-Weyl,
Methoden der Organischen Chemie, vol. 12/1, pages 465-467, G. Thieme Verlag,
Stuttgart, 1963). If diphosphonates were also obtained, these occurred in
moderate yield in addition to the monophosphonates (A.N. Pudovik, Zhurnal
Obshch. Khim. 22 (1952), 1371, ref. Chem. Abstr. 47 (1953), 4837). It was
therefore surprising that in the process described herein 2 moles of phosphite
are added easily. It was furthermore surprising that the ~-phosphono-a-
hydroxyphosphonates evidently formed as intermediate cyclise under the reaction
contitions rapidly and virtually completely to give the 1,2-oxaphospholane-
5-phosphonates.
It has furthermore been found that oxaphospholane derivatives of
the formula I can also be manufactured from the known y-ketophosphonates by
addition of dialkyl phosphites. This is an indication that the reaction
discussed above probably proceeds via the stage of the y-ketophosphonates. It
is therefore possible to carry out the reaction in two partial steps, the
first being the known addition of 1 mole of phosphite to a,B-unsaturated
ketones to form the y-ketophosphonates and the second being the reaction with
a second mole of phosphite to form the oxaphospholanes. This second step is
just as surprising and novel as the single step main process.
The invention therefore also provides a process for the manu-
facture of compounds of the formula I, which comprises reacting a compound
of the formula IV
0 R4 R6 j
(R30)2P- C- CH -C -R7 (IV)
- R5
- 10 -
1049030
with at least one mole of a phosphite of the formula III in the presence of
a base, with or without the addition of a solvent. In the formula IV, the
substituents R3 to R7 have the same meanings assigned to them as in respect
of the compounds of the formula I. The catalysts and solvents suitable for
use in this process are the same as those for the single step main process
described hereinbefore, and the reaction and isolation of the products are
carried out in the same way.
This modification is principally of importance for the manufacture
of those compounds of the formula I in which R3 is different from Rl and R2.
The compounds of the formula I are outstanding flameproofing
agents for thermoplastic polymers, polyurethanes, epoxy resins, cellulose and
also for cellulose derivatives. It has long been known to use phosphorus-
containing compounds as flameproofing agents for polymers, but it is normally
necessary to use the phosphorus compounds in high concentrations, which results
as a rule in a deterioration of the physical and technological properties of
the polymers.
The surprising discovery has now been made that the new 1,2-oxa-
phospholanes of the formula I impart an adequate flame resistance to the
; polymers even in relatively low concentrations. Moreover, on account of their
considerable heat stability they have only a minute influence on the physical
properties of the substrates. Further they are also usable in reactive systems,
such as in polyurethane foams or in epoxy resins which,both in their manu-
facture and use, are highly sensitive towards additives.
Examples of thermoplastic polymers which can be flame-protected
with the compounds of the formula I are:
1. Polymers which are derived from simply or doubly unsaturated hydrocarbons,
such as polyolefins, e.g. polyethylene, polypropylene, polyisobutylene,
' polymethylbutene-l, polymethylpentene-l, polybutene-l, polyisoprene, poly-
butadiene, polystyrene, polyisobutylene, copolymers of the monomers based on
the cited homopolymers, such as ethylene-propylene comonomers, propylene-
butene-l copolymers, propylene-isobutylene copolymers, styrene-butadiene co-
polymers, and terpolymers of ethylene and propylene with a diene, eOg.
- - 11 -
~049030
hexadiene, dicyclopentadiene or ethylidene norbornene; mixtures of the above
mentioned homopolymers, e.g. mixtures of polypropylene and polyethylene,
polypropylene and polybutene-l, polypropylene and polyisobutylene.
2. Halogen-containing vinyl polymers, e.g. polyvinyl chloride, polyvinylidene
chloride, polyvinyl fluoride, but also polychloroprene and chlorinated
rubbers.
3. Polymers which are derived from a,~-unsaturated acids and derivatives
thereof, e.g. polyacrylates and polymethacrylates, polyacrylamides and poly-
acrylonitrile and copolymers thereof with other vinyl compounds, such as
acrylonitrile/butadiene/styrene, acrylonitrile/styrene and acrylonitrile/
styrene/acrylic ester copolymers.
4. Polymers which are derived from unsaturated alcohols and amines and their
acryl derivatives or acetals, such as polyvinyl alcohol, polyvinyl acetate,
polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral,
and copolymers thereof with other vinyl compounds, e.g. ethylene/vinyl
acetate copolymers.
5. Polyacetals, e.g. polyoxymethylene and polyoxyethylene, and also those
polyoxymethylenes that contain ethylene oxide as comonomer.
6. Polyphenylene oxides.
7. Polycarbonates.
8. Polysulphones.
9. Polyamides and copolyamides which are derived from diamines and dicarboxy-
lic acids and/or aminocarboxylic acids or from the corresponding lactams,
e.g. polyamide 6, polyamide 6/6, polyamide 6/lO, polyamide ll, polyamide 12.
` 10. Polyesters which are derived from dicarboxylic acids and dialcohols
and/or the corresponding lactones, e.g. polyethylene glycol terephthalate,
polybutyrene terephthalate, poly-1,4-dimethylol-cyclohexane terephthalate~
` The flameproofing of cellulose and cellulose derivatives is
possible in those cases where the polymer is processed from solution or from
the melt, so that the flameproofing agent can be added to this solution or
melt. The cellulose xanthogenate solutions which are known as viscose
solutions and which are used for the manufacture of fibres and sheets of
- 12 -
:
. . .. ... ..
1049030
regenerated cellulose are one example. Solutions of cellulose acetate in
organic solvents are another example.
Polyurethanes which can be given a flameproof finish with the
compounds of the formula I can be both linear and branched polyurethanes such
as are used for the manufacture of films, fibres, brushes, coatings, elastic
materials and rigid and soft foam plastics. The flameproofing of polyurethane
foam plastics is of particular importance since such foams, like all materials
having a large surface area, burn more easily than compact materials.
It is common knowledge that such polyurethane foams or coating
compositions are manufactured from polyhydroxy compounds, e.gO polyesters or
polyethers which contain hydroxy groups on the one hand and polyisocyanates,
- e.g. toluylene diisocyanate, on the other. The introduction of flameproofing
agents of the formula I can be accomplished by adding them to the starting
components mentioned hereinbefore, i.e. simultaneously with the manufacture
of the polyurethanes, since the oxaphospholane derivatives scarcely influence
the pot life and curing time. Non-inflammable polyurethane foam plastics
or coatings with excellent mechanical properties and very good resistance to
ageing are thereby obtained.
The same applies to the flameproofing of epoxy resins. These
resins are usually manufactured by mixing an epoxide component with a hardener
component, whereupon a poly-addition reaction takes place between the two
components. The flameproofing agents of the formula I can be mixed both with
` the epoxide and with the hardener component since they are compatible with
both and such mixtures are storable. But it is also possible to add the
flameproofing agent only during the manufacture of the resin as third com-
ponent so long as the resin is still liquid and not yet formed.
Epoxy resins are used frequently in those cases where a high
` thermal stability of a resin under load is required~ Many organic flame-
proofing agents, for example phosphorus esters of chloroparaffins, effect a
perceptible reduction in the thermomechanical stability of epoxy resins.
However, such small amounts of the compounds of the formula I are required
for an effective flameproofing of epoxy resins that the thermomechanical
- 13-
, .
1049030
stability of these latter is not noticeably impaired.
The compounds of the formula I are normally added to the cited
substrates in an amount of 2 to 30% by weight, preferably 2 to 10% by weight,
based on the substrate. The addition can be carried out before or during the
manufacture of the substrate by polymerisation; but frequently the compounds
are added to the finished polymers before or during their processing.
In addition to the flameproofing agents of the formula I, it is
also possible to add to the polymeric substrates other flameproofing agents,
e.g. organic halogen compounds, antimony oxide or other phosphorus compounds.
It is furthermore possible to add other customary and known additives, e.g.
antioxidants, heat stabilisers, UV absorbers, fluorescent brighteners, anti-
static agents, lubricants, softeners, emulsifiers, pigments, carbon black,
asbestos, kaolin, talcum, glass fibres or other fillers and reinforcing agents.
The manufacture and utility of the oxaphospholanes of the formula
I are illustrated in re detail in the following Examples.
Example 1
Preparation of 2-Oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphos-
pholane
, .,
10 ml of diethyl phosphite are added to a solution of 98.1 g
(1 mole) of mesityl oxide in 300 ml of benzene and the mixture is then heated
to 80C. About 200 mg of metallic sodium are added to the almost boiling
solution, whereupon an exothermic reaction commences. The reaction is brought
to completion over the course of 10 minutes by gradual addition of altogether
345.0 g (2.5 moles) of diethyl phosphite and 402 g of sodiw. The reaction
mixture is stirred for further 10 minutes, neutralised with 11 g of glacial
acetic and evaporated in vacuum. The residue is distilled in a high vacuum.
The main fraction distills as an almost colourless oil at 136-139C and
; 0.035 mm Hg. After analysis, nuclear magnetic resonance and mass spectrum
this fraction is 2-oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-
oxaphospholane of the empirical formula C12H2606P2 (M = 328029).
Analysis:
calc.: C 43.90 H 7.99 P 18.92
- 14 -
10490;~0
found: C 44.30 H 8.00 P 18.0
The yield is 45.3% of theory.
The same reaction is carried out with 392 g (4 moles) of mesityl
oxide and 1660 g (12 moles) of diethyl phosphite in 1200 ml of benzene and
in the presence of 9.5 g of sodium. Upon completion of the reaction (40
minutes), the reaction mixture is neutralised with 24.8 g of glacial acetic
acid and distilled to yield 995.7 g of 2-oxo-2-ethoxy-3,3,5-trimethyl-5-
diethylphosphone-12-oxaphospholane which melts at 136-140C at 0.02-0.04
Torr. This corresponds to a yield of 75.9% of theoryO
Example 2
Preparation of 2-Oxo-2-methoxy-3,3,5-trimethyl-S-dimethyl-phosphono-1,2-
oxaphospholane
A solution of 30.0 g of sodium methoxide in 90 ml of methanol is
added dropwise to a mixture of 220 g of dimethyl phosphite and 98 g of mesityl
oxide over the course of 2 hours in such a way that the reaction temperature
does not exceed 65C. The clear solution is subsequently heatet for 2 hours
to 70C. The reaction mixture is concentrated in vacuo and the residue is
taken up in 200 ml of tolueneO The solution is filtered and the filtrate
tistilled. The 2-oxo-2-methoxy-3,3,5-trimethyl-5-dimethylphosphono-1,2-
oxaphospholane distills at 158-160C in the form of a colourless, viscous
oil.
Analysis, calc. for CgH20P206 (M = 286.20)
` calc.: C 37.80 H 7.05 P 21.65
fount: C 37.79 H 7.C4 P 21.32
~ ExamPle 3
`~` Flameproofing of a polyurethane foam
A soft polyurethane foam is manufactured by mixing the following
materials:
100 g of a polyhydroxy compound on a polyether basis with a
molecular weight of about 3000 and a OH number of 56
1 g of a siloxane-oxyalkylene copolymer
0.1 g of tin (II) octoate
- 15 -
1049030
3.5 g of water
48.2 g of toluylene diisocyanate (80:20 mixture of the 2,4-
and the 2,5-isomers)
x g of 2-oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-
1,2-oxaphospholane (compound of Example 1).
The foam so manufactured is tested for its flammability by the
ASIMD 1692 test method. For this purpose, test specimens each measuring 150
mm x 50 mm x 13 mm are fixed with the 50 mm x 13 mm surface in the horizontal
positionO Marks are made at 25 mm and 100 mm. The bottom end of the
10specimen is then ignited with a gas burner. The ignition time is 60 seconds~
The foam is termed flameproof if the burned zone is not longer than 25 mm.
If the specimen burns beyond the 25 mm mark and the burned zone is smaller
than 125 mm, then the foam is termed self-extinguishing. The length of the
burned zone is indicated in mm. If the specimen burns beyond the 125 mm,
the foam is termed combustible.
:. :
.,
.
,, :
~ - 16 -
.
:
1049030
_
~ N 00 N Ln _~
1~ ~ .
_ X
~ O O O O _l
~ 1~
~.
1~49030
Individual foam specimens are also subjected to the flameproofing
test after an ageing at 140C dry and 90C humid over the course of 1, 2,
4 and 7 days.
~: b O O O O O u~ o ~ u~
0~ 'D `D u~ ~
~0 bO ~:
~000
. .
¦ ~a ~ ¦ O u~ O ¦ :
1 ~2~ 1
:,.
::' .
`:
~3 u~ ,
~ ~ 3
., a~ ~ , ~ ~ I~
b b b b ~ @ ~ b b b
~t ~ ~O ~
.~ u~-~ ~ cd nl u~cn ~d cd t~ td .,
~.. ,
- 18 -
.~ . . .
1049030
These figures show that a storage resistant flameproofing is
obtained with 2-oxo-3,3,5-trimethyl-S-diethylphosphone-1,2-oxaphospholane
even if only 4 g of this compound per 100 g of polyol is used.
ExamPle 4
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-diethylPhosphono-1,2-oxaPhospholane
98 g of mesityl oxide (1.0 mole) and 415 g of diethyl phosphite
(3.0 moles) are dissolved in 300 ml of benzene and 200 ml of this solution
are heated to the boil. A catalytic amount of sodium is added whereupon a
vigorous exothermic reaction commences and the mixture boils by itself after
removal of the heating bath. After the sodium has dissolved the reaction
comes practically to a stop and is initiated a fresh by addition of a further
amount of sodium. In this manner sodium is added until the main reaction is
over. Then about one third of the remaining solution is passed in and this
is reacted as previously by adding sodium. The remaining two-thirds of the
solution are reacted in the same way. Altogether 3.0 g of sodium are used -
over the course of 25 minutes. The reaction mixture is allowed to continue
to react for 15 minutes at boiling temperature, then it is neutralised with
8 g of glacial acetic acid and diluted with 350 ml of benzene. After the
reaction solution has cooled, it is washed with two portions of water of 75
and 20 ml respectively. The combined aqueous phases are extracted with 50 ml
of benzene twice to give a solution in benzene which is combined with the
chief portion, dried with Na2SO4 and concentrated in a rotary evaporator.
Distillation yields 118.5 g of first runnings of b.p. 46-68C/8 mm Hg, which
largely consists of diethyl phosphite, and 280.8 g (85.6% of theory) of the
oxaphospholane which boils at 122-132C at 0.008 mm Hg. Gas chromatography
shows the product to be about 95% pure. 8.2 g remain as distillation residue.
Example S
2-Oxo-2-isopropoxy-3,3,5-trimethyl-5-diisopropylphosphono-l~2-oxaphospholane
As described in Example 4, a mixture of 19.6 g of mesityl oxide
(0.20 mole), 99.6 g of diisopropyl phosphite (0.60 mole) and 100 ml of benzene
` is reacted with 2.1 g of sodium as catalyst over the course of 10 minutes.
The reaction is vigorously exothermic. After a subsequent reaction of 15
.~ - 19 -
.
104~10
minutes at boiling temperature the reaction mixture is neutralised with 5.5
g of glacial acetic acid and diluted with 150 ml of benzene. After the
; reaction solution has cooled it is extracted with 20 ml of benzene twice and
the extract is combined with the chief portion, dried over Na2SO4 and concen-
trated in a rotary evaporator. The distillation yields 27.5 g of first
runnings with a boiling point of 68-75C/10 mm Hg and consisting of virtually
pure diisopropyl phosphite as well as 58.0 g (78.3%) of the oxaphospholane
which boils at 120/0.02 mm Hg to 125C/0.05 mm Hg; 5.3 g remain as residue.
Analysis~ for C15H326P2 (M = 370-37)
calc.: C 48.64 H 8.71 P 16.73
found: C 48.77 H 8.92 P 16.37
The mass spectrum shows the molecular peak at m/e 370.
ExamPle 6
2-Oxo-2-ethoxy-4,5-dimethyl-5-diethylphosphono-1,2-oxaphosPholane
In analogous manner to Example 4, a mixture of 25 g of freshly
distilled methyl isopropenyl ketone (0.30 mole), 124 g of diethyl phosphite
(0,90 mole) and 75 ml of benzene are reacted with 2.5 g of sodium over the
course of 10 minutes. The reaction is vigorously exothermic. After a
subsequent reaction of 10 minutes at boiling temperature, the reaction mixture
~; 20 is neutralised with glacial acetic acid and diluted with 300 ml of benzene.
After the reaction solution has cooled, it is extracted with 60 ml of H20.
The aqueous phase is extracted twice with 60 and 30 ml of benzene respectively
and the extract is combined with the chief portion, dried over Na2SO4 and
concentrated in a rotary evaporator. The distillation yields 49.2 g (52.2%
of theory) of the oxaphospholane of b.p. 128-132C/0.002 mm Hg.
AnalysiS, for CllH24O6P2 (M = 314-26)
. .~
calc.: C 42.04 H 7.70 P 19.71
~ found: C 41.78 H 7.69 P 19.39
- The mass spectrum shows the molecular peak at m/e 314.
Example 7
2-Oxa-2-butoxy-3,3,5-trimethyl-5-dibutylphosphono-1,2-oxaphospholane
A reaction solution is prepared from 194 g (1 mole) of freshly
- 20 -
104903V
distilled dibutyl phosphite and 32.4 g (0.33 mole) of mesityl oxide in 200 ml
of absolute benzene.
30 ml of this mixture are put into the reaction flask and treated
with about 50 mg of sodium. An exothermic reaction commences and the tempera-
ture rises to 70C. After the reaction has subsided, the reaction mixture
is broughtto reflux temperature by addition of reaction solution in small
amounts and of 1.5 g of s~dium. Stirring is continued for 1 hour at 70C and
the reaction mixture is subsequently neutralised with glacial acetic acid.
Distillation yields the product with a boiling point of 158-
162C/O.Ol mm.
Example 8
2-Oxa-2-cyclohexoxy-3,3,5-trimethyl-dicyclohexylphosPhono-l~2-oxaphospholane
` 88 g (0.35 mole) of freshly distilled dicylohexyl phosphite are
dissolved in 150 ml of absolute benzene and the solution is warmed to 50C.
After addition of 2 g of sodium, 15 g (0.14 mole) of freshly distilled mesityl
oxide are added dropwise. The exothermic reaction causes the temperature of
the mixture to rise to 70C. After termination of the reaction, the reaction
mixture is stirred for further 2 hours and then neutralised with glacial
acetic acid. The filtered solution is distilled and the product with a
boiling point of 150-153C/O.Ol mm Hg is obtained.
Example 9
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaPhosPholane
690 g of diethyl phosphite and 50 g of a sodium methoxide solution
(17 g of sodium dissolved in 83 g of ethanol) are mixed in a sulphurating
flask. With stirring, 245.5 g of mesityloxide are dropped into this solution
over the course of 40 minutes. During the dropwise addition an exothermic
reaction takes place, the reaction temperature rising from 20C to 101C when
` up to half the a unt of mesityl oxide has been added. The temperature then
falls to 75C when the second half of the mesityl oxide is added. The colour-
less, clear solution is stirred for 50 minutes and the temperature in the
reaction mixture falls to 39C. Then a further 25 g of sodium methoxide
solution are added all at once, whereupon the temperature of the reaction
- 21 -
~049030
mixture rises from 39 to 84C. The reaction mixture is stirred for 30
minutes and then 25 g of sodium methoxide solution are added. The resultant
reaction mixture is stirred for 3 hours at room temperature and subsequently
neutralised with 15 g of glacial acetic acid. Distillation of this reaction
mixture yields at 162-167C/0.05 mm 626 g of 2-oxo-2-ethoxy-3,3,5-trimethyl-
5-diethylphosphono-1,2-oxaphospholane as a colourless liquid. Chromatographic
analysis shows a purity of 99.1%.
Example 10
2-Oxo-2-ethoxy-5-methyl-5-diethylphosphono-1,2-oxaphosPholane
276 g (2 moles) of freshly distilled diethyl phosphite are treated
with a solution of 3.5 g of sodium methoxide in 20 ml of absolute ethanol and
70 g (1 mole) of freshly distilled methyl vinyl ketone are added dropwise
thereto. The exothermic reaction causes the temperature of the mixture to
rise to about 70C. After the whole amount of methyl vinyl ketone has been
dropped in, stirring is continued for 2 lt2 hours and the reaction mixture
is neutralised with glacial acetic acid. After a first runnings which con-
sists largely of diethyl phosphite and methyl vinyl ketone, the distillation
at 0.01 mm yields the product with a boiling point of 120-133C.
ExamPle 1 1
2-Oxo-2-ethoxy-5-ethyl-diethylphosphono-1,2-oxaphospholane
138 g (1 mole) of freshly distilled diethyl phosphite are treated
with a solution of 1.75 g (0O075 mole) of sodium in 10 ml of absolute ethanol
and 42 g (0.5 mole) of ethyl vinyl ketone are added dropwise thereto. The
exothermic reaction causes the temperature of the mixture to rise to 70C.
After the whole amount of ethyl vinyl ketone has been dropped in, the reaction
i ; is brought to completion by adding once more 1 g (0.04 mole) of sodium in 10
ml of absolute alcohol when again a rise in temperature to 60C is observed.
`t Stirring is continued for 2 hours and the reaction mixture is then neutra-
lised with glacial acetic acid. After a first runnings which consists largely
of diethyl phosphite and ethyl vinyl ketone, the distillation at 0.1 mm
yields the product having a boiling point of 132-138C.
- 22 -
; ~. ~ ' '' :.
1049030
Example 12
2-Oxo-2-ethoxy-3-phenyl-5-methyl-5-diethylphosphono-1,2-oxaphospholane
276 g (2 moles) of freshly distilled diethyl phosphite are treated
with a solution of 3.5 g (0.15 mole) of sodium in 20 ml of absolute ethanol.
At 40C, 146 g (1 mole) of benzalacetone are dissolved in 50 ml of absolute
ethanol and this solution is added dropwise to the first solution. The exo-
thermic reaction causes the temperature of the mixture to rise to 90C over
the course of 1 hour. After completion of the addition of benzalacetone, the
reaction mixture is stirred for 3 hours and neutralised with glacial acetic
acid. The product is isolated in the subsequent distillation at 187-
210C/0.01 mm.
Example 13
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphosPholane
10 ml of a mixture of 70.8 g of 4-methyl-4-~diethylphosphono)-
pentanone-2 (prepared from mesityl oxide and diethyl phosphite) and 82.8 g
of diethyl phosphite are dissolved in 100 ml of toluene and the solution is
heated to 80C. A catalytic amount of sodium is added and a vigorous exo-
thermic reaction commences. The reaction temperature is held between 80C and
90C by alternately adding the previously prepared mixture and small pieces of
sodium. Altogether 1.65 g of sodium are used as catalyst. The reaction takes
! 20 minutes. The reaction mixture is subsequently stirred at 80C-90C for
30 minutes with heating, then cooled and neutralised with 4.5 g of glacial
acetic acid. This reaction mixture is distilled to yield 2-oxo-2-ethoxy-3,3,5-
trimethyl-5-diethylphosphono-1,2-oxaphospholane with a boiling point of 156C-
161C/l.l mm. This substance is identical with the oxaphospholane manufac-
tured ascording to Example 4.
Example 14
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-dimethylphosphono-1,2-oxaphospholane
By carrying out the same procedure as described in Example 13,
2-ethoxy-3,3,5-trimethyl-5-dimethylphosphono-1,2-oxaphospholane with a boiling
point of 146-148C/0.5 mm is obtained from 70.8 g of 4-methyl-4-(diethyl-
phosphono)-pentanone-2- and 66.0 g of dimethyl phosphite with 1.65 g of sodium
- 23 -
1049030
as catalyst.
Example 15
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-di-(isopropyl)-phosphono-l~2-oxaphospholane
By carrying out the same procedure as described in Example 13,
2-ethoxy-3,3,5-trimethyl-5-di-(isopropyl)-phosphono-1,2-oxaphospholane with
a boiling point of 180-185C/2 mm is obtained from 70.8 g of 4-methyl-4-
(diethylphosphono)-pentanone-2 and 99.6 g of diisopropyl phosphite with 4.6
g of sodium as catalyst.
Example 16
2-Oxo-2-methoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphospholane
By carrying out the same procedure as described in Example 13,
2-oxo-2-methoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphospholane with
a boiling point of 144-146C/0.6 mm is obtained from 83.2 g of 4-methyl-4-
(dimethylphosphono)-pentanone-2 and 110.4 g of diethyl phosphite with 1.15 g
of sodium as catalyst. The p31 spectrum shows for the phosphorus atom in
the 5-ring a shift of -48 ppm compared with H3PO4 as standard.
Example 17
2-Oxo-2-ethoxy-3,3,S-trimethyl-5-di-(isooctyl)-phosphono-1,2-oxaphospholane
By carrying out the same procedure as described in Example 13,
2-oxo-2-ethoxy-3,3,5-trimethyl-S-di-(isooctyl)-phosphono-1,2-oxaphospholane
is obtained as a viscous, colourless oil from 47.2 g of 4-methyl-4-(diethyl-
phosphono)-pentanone-2 and 84.6 g of di-isooctyl phosphite with 1.15 g of
sodium as catalyst. The p31 spectrum of this oil shows for the phosphorus
atom in the ring a shift of -49 ppm compared with H3PO4 as standard.
Example 18
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-di-n-octylPhosphono-1,2-oxaphospholane
: By carrying out the same procedure as described in Example 13,
~ 2-oxo-2-ethoxy-3,3,5-trimethyl-5-di-n-octylphosphono-1,2-oxaphospholane is
obtained as a viscose, pale yellow oil from 47.2 g of 4-methyl-4-(diethyl-
Y` 30 phosphono)-pentanone-2 and 84.6 g of di-n-octylphosphite with 1.15 g of sodium
as catalyst. The p31 spectrum of this oil shows for the phosphorus atom in
the ring a shift of -49 ppm compared with H3PO4.
- 24 -
- .' '.' ' ' ... ' ~ ~ ' ..
1049030
Example l9
2-Oxo-2-ethoxy-3,3,5-trimethyl-5-di-(-2-chloroethyl)-phosphono-1,2-oxaphos-
lane
By carrying out the same procedure as described in Example 13,
2-oxo-2-ethoxy-3,3,5-trimethyl-5-di-(2-chloroethyl~-phosphono-1,2-oxaphos-
pholane is obtained from 47.2 g of 4-methyl-4-(diethylphosphono)-pentanone-2
and 45.2 g of bis(2-chloroethyl)-phosphite. In the p31 spectrum, this com-
pound shows for the phosphorus atom in the ring a shift of -50.2 ppm compared
with H3PO4 as standard.
Example 20
2-Oxo-2-propyloxy-3,3,5-trimethyl-5-dipropylphosphono-1,2-oxaphospholane
11.8 g of mesityl oxide and 9.8 g of dipropyl phosphite are
heated in 40 ml of benzene to 80C. At this temperature, 0.1 g of sodium is
added, whereupon an exothermic reaction commences. The reaction temperature
is held at 80-90C with external heating by alternately adding 40.0 g of
dipropyl phosphite and 0.4 g of sodium. After all the sodium has been added,
stirring is continued for 30 minutes, the reaction mixture is cooled and
neutralised with 1.4 g of glacial acetic acid. The reaction mixture is
concentrated in a rotary evaporator and then distilled in a high vacuum to
yield 2-oxo-2-ethoxy-3,3,5-trimethyl-5-dipropylphosphono-1,2-oxaphospholane
in the form of a colourless oil with a boiling point of 153-154C/0.1 mm.
The p31 spectrum shows for the phosphorus atom in the ring a shift of -67.2
ppm compared with triphenylphosphate as standard.
Example 21
:,
2-Oxo-2-t2-methoxyethoxy)-3,3,5-trimethyl-5-di-(2-methoxyethyl)-phosphono-
1,2-oxaphospholane
15.7 g of mesityl oxide and 9.2 g of di-(2-methoxyethyl)-phosphite
are heated to 80C in 50 ml of benzene. At this temperature, 0.1 g of sodium
is added whereupon an exothermic reaction commences. The reaction temperature
3Q is held between 80-90C without external heating by alternately adding
70.0 g of di-~2-methoxyethyl)-phosphite and 0.6 g of sodium. After all the
sodium has been added, the reaction mixture is stirred for 30 minutes at 80C,
- 25 -
... .
1049030
cooled and neutralised with 1.75 g of glacial acetic acid. The reaction
mixture is concentrated in a rotary evaporator and the residue is distilled
in a high vacuum to yield 2-oxo-2-(2-methoxyethoxy)-3,3,5-trimethyl-5-di-(2-
methoxyethyl)-phosphono-1,2-oxaphospholane in the form of a colourless oil
with a boiling point of 193-196~C/0.07 mm. The p31 spectrum shows for the
phosphorus atom in the ring a shift of -67.2 ppm compared with triphenylphos-
phate as standard.
Example 22
2-Oxo-2-allyloxy-3,3,5-trimethyl-5-diallylphosphono-1,2-oxaphospholane
11.5 g of mesityl oxide and 7.4 g of diallylphosphite are heated
to 80C in 40 ml of benzene. At this temperature, 0.1 g of sodium is added.
An exothermic reaction starts and the reaction temperature is held at 80-
90C without external heating by alternately adding 40.0 g of diallylphosphite
and 0.4 g of sodium. After all the sodium has been added, the reaction
mixture is stirred for 30 minutes at 80C, then cooled and neutralised with
1.3 g of glacial acetic acid. The reaction mixture is concentrated in a
` rotary evaporator to yield as residue 2-oxo-2-allyloxy-3,3,5-trimethyl-5-
; diallylphosphono-1,2-oxaphospholane in the form of a pale yellow oil. The p31
spectrum shows for the phosphorus atom in the ring a shift of -68.5 ppm
comparet with triphenylphosphate as standard.
Example 23
2-Oxo-2-ethoxy-3-(4-methoxyphenyl)-5-methyl-5-diethylphosphono-1,2-oxaphos-
pholane
A mixture is prepared of 69.0 g of diethyl phosphite and 5 g of a
17% sodium ethoxide solution in ethanol. To this reaction mixture are added
in small amounts 44 g of p-methoxy-benzalacetone, whereupon the temperature
rises from 25C to 89C. The reaction mixture is stirred for 50 minutes and
then a further 2.5 g of the 17% sodium ethoxide solution are added. After a
further 30 minutes 3.5 g of diethyl phosphite and 2.5 g of sodium ethoxide
solution are added to give a pale yellow, clear solution which is concentrated
in a rotary evaporator. The p31 spectrum for the phosphorus atom in the ring
of the 2-oxo-2-ethoxy shows a shift of -58 ppm compared with triphenylphos-
- 26 -
r. :
~''`- '` , ' ~ ' '
1049030
phateO
Example 24
2-Oxo-2-ethoxy-3-(4-methylphenyl)-5-methyl-5-diethylphosphono-1,2-
oxaPhosPholane
By carrying out ~he same procedure as described in Example 23,
2-oxo-2-ethoxy-3-(4-methylphenyl)-5-methyl-5-diethylphosphono-1,2-oxa-
phospholane is obtained from 3002 g of 4-methyl-benzalacetone and 5407 g of
diethyl phosphite with 7.8 g of a 17% sodium ethoxide solution in ethanol.
The p31 spectrum of the product shows a shift of -58 ppm for the phosphorus
atom in the ring.
Example 25
2-Oxo-2-ethoxy-3-(4-chlorophenyl)-5-methyl-5-diethylphosphono-1,2-oxa-
phospholane
By carrying out the same procedure as described in Example 23,
2-oxo-2-ethoxy-3-(4-chlorophenyl)-4-methyl-5-diethylphosphono-1,2-oxaphos-
pholane is obtained from 4502 g of 4-chloro-benzalacetone ant 72.5 g of
diethyl phosphate with 10 g of a 17% sodium ethoxide solution in ethanol. The
p31 spectrum of the product shows a shift of -57.5 ppm for the phosphorus
atom in the ring compared with triphenylphosphate.
ExamPle 26
:' 2-Oxo-ethoxy-3-furyl-5-methyl-diethylPhosphono-1,2-oxaphosPholane
By otherwise carrying out the same procedure as described in
Example 23, 2-oxoethoxy-3-furyl-5-methyl-diethylphosphono-1,2-oxaphospholane
is obtained from 34.0 g of furfurylidene acetone and 7205 g of diethyl
phosphite with 10 g of a 17% sodium ethoxide solution in ethanol. The p31
spectrum of the product shows a shift of -5503 ppm for the phosphorus atom in
the ring compared with triphenylphosphate.
Example 27
Flameproofing of polyethylene terePhthalate
15 parts of a commercially available polyethylene terephthalate
are dissolved in 85 parts of hexafluoroisopropanol. This solution is mixed
with the corresponding amount of flame-proofing agent and stirred until it is
_ 27 -
.
~049030
homogeneous. Using a film drawing rod, half of the solution is applied to a
glass plate to a thickness of 0.5 mm. A glass cloth is then pressed on the
film and is coated by the second half of the solution in a thickness of l mm.
Drying in vacuo at 120C over 16 hours is subsequently effected. The dried
film is drawn from the glass plate and the fl _ ability is determined by the
LOI method described by C.P. Fenimore and J.F. Martin in "Combustions and
Flame" 10, No. 2, 135-139 (June 1966). In this test, the film is ignited in
an atmosphere of nitrogen and oxygen of different volume composition and the
volume ratio is ascertained at which it is still just possible to maintain
combustion of the test specimens. The LOI value is the minimum oxygen concen-
tration in a nitrogen-oxygen mixture at which the specimen just still burns.
The higher the LOI value the lower the flammability of the sheeting, i.eO the
more effective the addition of flameproofing agentO
.
flameproofing agentamount of flameproofing agent* LOI
.~
flameproofing agent 5~ 0,225
according to
Example 1
flameproofing agent 10% 0,250
according to
Example l
without flameproof- __ 0,200
ing agent
*based on polyethylene terephthalate
ExamPle 28
FlameProofing of a Polyamide
15 parts of a commercially available nylon 6 are dissolved in 85
parts of trifluoroethanol. This solution is mixed with the corresponding
amount of flameproofing agent and homogeneously stirredO Films are prepared
in a manner analogous to that described in Example 27 for polyethylene tere-
phthalate and the LOI values are determined. The following Table shows how
the LOI value is increased by addition of the flameproofing agents according
-` to the invention as compared with nylon 6 without flameproofing agentO
- 28 -
1049030
flameproofing agentamount of flameproofing agent* LOI
.
flameproofing agent 5% 0~216
according to
Exsmple 1
flameproofing agent 10% 0~231
according to
Example 1
without flameproof- __ 0~ 196
ing agent
*based on nylon 6
Example 29
Flameproofing of polyacrylonitrile
201 parts of commercially available polyacrylonitrile are dis-
solved in 80 parts of dimethyl formamide. This solution is mixed with the
corresponding amount of flameproofing agent and stirred to homogeneity.
Sheetings are prepared in a manner analogous to that described in Example 27
for polyethylene terephthalate and the LOI values are determined. The follow-
ing Table shows how the LOI value is increased by addition of the flameproof-
ing agents according to the invention as compared with polyacrylonitrile
without flameproofing agent.
~; flameproofing agentamount of flameproofmg agent LOI
flameproofing agent 5% 0,207
according to
Example 1
flameproofing agent 10% 0~224
according to
Example 1
without flameproof- __ 0~189
ing agent
Example 30
2-Oxo-2-tetrahydrofuryloxy-3,3,5-trimethyl-5-di-(tetrahydrofurfuryl)-phosphono-
1,2-oxaphospholane
As described in Example 1, a mixture of 3?o6 g of di-tetrahydro-
furfuryl phosphite and 4~9 g of mesityl oxide in 80 ml of benzene is reacted
~ 29 ~
1049030
by heating in the presence of 1.3 g of sodium over the course of 1 hourO The
reaction is vigorously exothermicO The sodium is neutralised by adtition of
3.4 g of glacial acetic acid, then inorganic salt is extracted from the mix-
ture with 2 times 20 ml of waterO The benzene is removed in a rotary evapora-
tor leaving as residue 32.6 g of crude product which still contains di-
tetrahydrofurfuryl phosphite. Distillation of 4.3 g of the crude product in
a bulb tube oven in a high vacuum yields the reaction product at an oven
temperature between 185C and 230C and a pressure of 0.01 mm Hg.
Yield: 2.07
Analysis: C21H38P209 (M = 496048)
calc.: C 5008 H 7.7 P 1205
found: C 49O5 H 7.7 P 12.6
Although the mass spectrum does not show the molecular peak at
m/e 496 it does show instead the MIH peak at /e 497. Fragments character-
istic of this compound occur at m/e 426 (M -C4H60) and 413 (M -C5H70).
ExamPle 31
Flameproofing of ePOxy resins
A rigid foam based on epoxide resin was manufactured from the
following constituents:
~` 20 resin: 105 parts of epoxide resin based on bisphenol A with an
epoxide equivalent weight of 190
45 parts of epoxide resin based on bisphenol A with an
epoxide equivalent weight of 400
2 parts of foam stabiliser Si 3193 (MessrsO Rhodia;
a glycol-silicone copolymer)
5 parts of pentane
5 parts of trichloromonofluoromethane
hardener: 7 parts of die*hylene triamine
7 parts of di-~aminomethyl)-cyclohexylmethane
1 part of bisphenol A
12 parts of 1,6-diamino-2,4,4-trimethylhexane
3 parts of phenol
- 30 -
.
1049030
Resin and hardener are thorougly mixed at room temperature and
poured into a wooden mould~ The foam is removed after 1 hour; it has a
density of 0.1 g/cm2.
Specimen rods measuring 10 x 15 x 120 mm are cut from the rigid
foam and subjected to a flammability test according to ASTM 635. In this
test, the rod is hung at an angle of 45 and ignited at its bottom end with
a gas flame. The combustion time up to the 10 cm mark is measured and the
combustion speed is calculated therefrom. The rigid epoxide foam has a com-
bustion speed of 2 secO/cm.
An epoxide foam of the same composition is manufactured except
that 25 parts of 2-oxo-2-ethoxy-3,3J5-trimethyl-5-diethyl-phosphono-1,2-
oxaphospholane are additionally mixed with the resin. The test of this foam
by ASTM 635 shows that the resin is self-extinguishing: the measurement mark
is not reached
., .
~ - 31 -
.
:, :
' ' '
