Note: Descriptions are shown in the official language in which they were submitted.
~3~3~7
-- 2 --
The present invention relates to flame retardant
compositions containing significant amounts of a
thermoplastic polymer from a vinyl aromatic monomer,
such as styrene, and co-polymers and polyblends
containing a polymer from a vinyl aromatic monomer.
A polymer composition containing polystyrene and
an aromatic polyether, for example polystyrene and
poly phenylene oxids is flammable and where resistance
to burning is required the polymers are traditionally
made flame retardant by adding flame retardants
containing phosphorus, halogen, antimony or any
combination of these. The triaryl phosphate, tri-
phenyl phosphate has been described as a flame
retardant for these polymer compositions, However,
when this compound is present in amounts necessary for
flame retardance a substantial decrease in heat
distortion temperature occurs, Also, triphen~ phosphate
is too volatile and evaporates from the composition
during processing of the polymer, when high processing
temperatures are used, i.e. above 200C. Thus, an
initial excess of triphenyl phosphate has to be
incorporated into tha polymer composition in order to
allow for this loss on processing.- Tri-mesityl
phosphate has also been described as a flame retardant
for polystyrene/poly phenylene oxide compositions in
United Sta-tes Patent Speci~ication No. 388361'.
This phosphate does not cause a marked reduction in the
heat distortion temperature, but its flame retardant
~3~ 7
properties are insufficient.
There is, thexefore, a need for an additive which
gives good flame retardance, but has less effect on the
heat distortion temperature of the polymer than does tri-
phenyl phosphate.
Surprisingly, we have ound that certain triaryl phos-
phates combine the properties of acceptable heat distor-
tion temperature with suficient flame retardance and have
lower volatility than triphenyl phosphate.
Accordingly, the present invention provides composi-
tions comprising:
(i) a polymer of styrene or other vinyl aromatic mono-
mer, or a copolymer selected from the group consisting of
styrene/a-methyl styrene, styrene/acrylonitrile, styrene
acrylates, acrylonitrile/butadiene/styrene, styrene/buta-
diene (high impact polystyrene), styrene/ethylene , styre-
ne/propylene and styrene/butylene, or a polymer blend
selected from the group consisting of polystyrene/poly-
vinyl chloride, styrene/nitrile rubber, styrene/isopropene
~ubber, polystyrene/polyphenylene oxide and styrene-buta-
diene co-polymers/polyphenyleneoxide, and (ii) from 1 to
100 parts by weight per 100 parts of polymer of a triaryl
phosphate of the formula
~ CH3 )3-x ~ ~ 2 x
where x is 0, 1 or 2 and Rl, R2 and R3 are the same or
different and represent hydrogen or an a:Lkyl group having
1 to 9 carbon atoms.
:
.
,.
.
31~30r~
-- 4
Rl, R2 and R3 can occupy any positions on the ring,
but the 21 4 and 6 positions are preferred.
Non-limiting examples of the triaryl phosphakes
are
tris (2,6-dimethyl phenyl) phosphate
bis ~2,6-dimethyl phenyl) phenyl phosphate
mono (2,6-dimethyl phenyl) dlphenyl phosphate
bis (2,6~dimethyl phenyl) 4-t-butyl phenyl phosphate
bi 3 (2,6-dimethyl phenyl) 4-methyl phenyl phosphate
bis (2,6-dimethyl phenyl) 3-methyl phenyl phosphate
bis (2,6-dimethyl phenyl) 4-isopropyl phenyl phosphate
bis (2,6-dimethyl phenyl) 2-isopropyl phenyl phosphate
In ~ormula I Rl, R2, R3 are preferably hydrogen or
; Cl - C4 alkyl, more preferably hydrogen or methyl and most
preerably hydrogen.
Non-limiting examples of the vinyl aromatic polymers
ara polystyrene, poly a-methyl styrene, polyvinyl toluene
polychlorostyrene.
Preferred are polymer blends of polyphenylene oxide
and polystyrene or a co-polymer of styrene and butadiene,
the polyphenylene oxide being described by the
general ~ormula:
: ~ :
::
,. . .
! ' . ' , ' ~:, . I
~3~;3~?~
-- 5 --
~ 4\~_./ 5
\o\-~ ~
R7 R6 J
n
wherein R4, R5, R6 and R7 may be the same or different,
: and ea~h is a hydrogen or haloyen atom, or a hydro-
aarbon, sub~tituted hydrocarbon, cyano, alkoxy, phenoxy,
: amino, .qulpho or n~tro group and n is a whole number
o at least 50. For example, R4, R5, R6 and R7 may be
hydrog~n, chlorlne, bromine or a methyl, ethyl, propyl,
~ allyl, phenyl, benzyl, methyl benzyl, cyanoethyl,
- cyano, methoxy, ethoxy, phenoxy or nitro group.
~pecific non-limiting examples o such polyphenylene
~xides include poly 2,6-dimethyl-1,4-phenylene oxide,
'~ poly-~,6-diethyl-1,4-phenylene oxlde, poly-2,6-dipropyl-
`~ 1,4-phenylene oxide, poly-2,6-dimethoxy-1,4~phenylene
oXide, poly-2,6-dimethoxy-1,4-phenylene oxide,
poly 2,6-dichloro-l,4-phenylene oXide.
'~
:
: .~
..
~-
.
- ~3~3~
The preferred polyphenylene oxide is poly-2,6-di-
methyl-1,4-phenylene oxide. The preferred poly-
blend is high impact polystyrene and poly 2,6-di-
methyl-1,4-phenylene oxide, e.g. those sold und~r
the 'rrademark ~ oryl.
The amounts of triaryl phosphate per hundred parts
o polymer preferably employed are ~rom 2 to 35 parts
and most preerably ~rom 5 ko 25 parts by weight. ~he
amounts o~ phosphate used will vary depending on the type
of polymer, the properties required and the amount and
type of other ingredients which may be present.
The composikions of the invention may also contain
an oligomer of the general formula II
,
a ( H2 )b[ CH2(0CH2)moCH2-]C(-CH2X)d II
';~
. wherein A is at least one aromatic hydrocarbon or
heterocyclic residuel X is a leaving group, a is 2 to
20 but equals b ~ c + 1, b ls 0 to 19, c is 0 to 19,
~: d is 0 to 2a and m is 0 to 10, preferably 0 to 5, most
~: preferably 0, there being at least two (-CH2X) groups
per molecule, the group (-CH20CH2-) counting as t-CH2X)
~: for this purpose when m = 0, and the group (-CH20)
: counting as a (-CH2X) group when m ~ 1.
:
~`
~ ~-3
~ :'7
~. ' ' ' . : ''
:" ' ' ' '`' ' ' ' ~ ' '. '
,
.
1~3~i3~7
-- 7 --
It should be noted that the~ ~alues of a, b, c, d
and n are average values for the average molecule of
formula II.
Leaving group X i~ formula II is halogen, -OH, -SH,
-NH2, -C02H, -P03H2, OB~OH)2 and their derivati~es, for
example -ORl, -SRl, _NHRl NRlR2 OB( 1)( 2 Non-
limiting examples o~ such deri~atives and other X group~ may
be represented by the general ~ormulae
W L y2R2 M
.. . . .
w~ere
Y~ ~ and ~ are, independently, O-~ -NH-, -N-, -S~, or
R
are absent, but preferably are -O- or -S-
1 Rl SRi NH NHR~ R2 or a direct bond.link~n~ C back to R or to a CH2 attac~ed to R
but prafar~bly i.s H or R ;
W is O~ S~ ~ or NRl9 but pre~erably is O or S;
L is O~ S or is absent~ but preferably is O;
M is O or is abso~t, but prc~orably is O;
.~.. ,., .. ,~__, . ;_ _ ____ ,.. _ _.... ___. .... ___ _ .. ~ .__.. .... _., .. _......... . . .
.
1J~3~i3~
-- 8 --
~nd whcr~in Rl represents a straicht or branched chain
al~yl ha~ing 1 to 12 carbon atoms, preferably 1 to 4, ~ut
most preferably 1, alkenyl or allc~nyl having 2 to 12 carbon
~to~s, preferably 2 to 4, cycloalkyl or cycloalkenyl havin~
5 to 12, preferably 6 carbon at;oms, aralkyl, aralkenyl or
aIkaryl i-aving 7 to 12 carbon atoms, preferably benzyl or
.. ... . ..
naphthyl methyl or aryl having 6 to 15, preferably 6 to
12 carbon atoms~ most preferably be~zyl or napht~yl methyl.
R may be optionally substituted by one or more halo~en,
hydroxy, epoxy, nitrile, amine, amidey ether, carboxyl or
ester ~roups or combin~tions thereof~ but is pre~erably
unsubstituted. R2 has the same significance as Rl and
may be the same or di~ferent. The lea~in~ group may also
be a salt o~ an acidic or basic X ~roup.
Howe~er, o~ the non-limitin~ examp~es, compounds of
~ormula I where X 3 OX or a derivative of this group are
preferred.
Examples of aromatic residues A are benzene 7
naphthalene, furan9 anthracsne, biphenyl and diphenyl
ether. The aromatic residue A may be unsubstituted or
substituted by one or two substituents. It is
preferably unsubstituted, but if it is substituted it
preferably carries only one substituent. Suitable
substituents include halogen, alkyl groups with 1 to 4
carbon atoms, haloalXyl groups with 2 to 4 carbon atoms,
' .
~ ,,, . . ~ . . . . . . . . . . .
~.
'
` 1~3~3~
g
and the group oR3 where R3 i9 hydrogen, alkyl with 1 to 4
carbon atoms or acyl with 1 to 4 carbon atoms.
The compounds represented by ~ormula II are mixtures
of oligomers with a range o~ molecular weights. The
residues A are linked by (-CH~-) or ~-CH2(0CH2)mOCH2-]
groups, these two linking groups being connected only to
a residue A and not to each other. The groups (-CH2X)
are connected to a residue A.
Pre~erably greater than 50 mol ~0 of residue,s A are
deri~ed from naphthalene; most pre~erably more than '~
75 mol ~ of residues A are derived from naphthalene.
Oligomers which are preferred are those having a
number average weight of 300 to 3500, more preferably
thoqe having a number average molecula~ weight of 350 - 1500,
most preferably 400 to lOOQ. It is preferred that the
naphthalene residues are linked by (-CH20CH2-) and that
these links should be attached to t~e positions 1,4;
1,5; 1,6; 1,7; 2,5; 2,6 or 2,7 on the naphthalene residue.
It is most preferred that the links should be attached to
the 1,4 or 1,5 positions on the naphthalene residue.
No,n-limiting examples o~ particular oligomers of
structure II are those linked by the group -C~20CH2-
and having two or more -CH2X groups per molecule.
Preferred structures which can be pr~sent as a component
of the oligomer mixture are shown below. The group
-CH20~H2- being counted as a -CE2X group.
.
113~
10 --
r~ o c~ e~
~J
, u2, o c
~c~ c~ c~ c~
(~CH~)~ ~7 I ca~x
Where m = O or 1~ and X = OH
O
Il
-OC CH3
-O~H2 ~ or
-O ~
Specific Examples of oligomers of formula II abo~e are
listed in Table A.
.. , .. ~
" ~3~3~7
_ ~ o ~ ~ ~ X
"
a
e o o o o ~ o
. , ~
o ~
~1 00 ~~ 00 0
. . .. . .
~I o oo o
o ~U O ~
~ ~ o ~ U~ ~
O
_
~ ~ ~ ~, o
U~ O ;t ~O CU ~ ~
~ ~ O O O O ~i 0 ~ ~
~, ~ _ ~ ~ ~
~1 u~ C~ ~ N ~ 1 ~ o
I t3 1~ ~ ~ CO ~oo
t~ c~l c~ t ~ h h
. . _ ,~ ,6D
~:: ~ h o o
~1 ~ ~ ~,
o ~ ~ ~ o o
O h o ~ ~ l ~ ~
rl O ~-rl ~ ~) ~
O ~ O ~ ~ ~ ~ ~ ~
13 h h P:; ~ o
O ~ h p~ P ~ ~ ;3
h ~ O O
h
. ~ ,~
_ . , __ o
a~ a~
h o o
~ ,q o ~ o o o ~o~u~ ~I C`l
~ ~ ~ oo
rl~ri ~ ~ U~
o a~
X ~
- 12 -
The addition o~ ~uch aD. oligom~r is e3pecially
usef`ul in thinner section s~eets, e.g. 1,5 mm. pro~idi.ng
polymer sheets which do not drip when burnt in the
manner described in the following Examples.
The compositions of the~ in~ention may also contain a
novolak in addition to or instead of the oligomer.
No~olaks used in accordance with the pr~sent i~vantion
may be any no~olak prepared by known methods from an
aldehyde and a phenolO Usually the molar ratio of
phenol:aldehyde i~ lsO.9 or less and the reaction may be
ef~ected under acid or alkaline conditions. Suitable
phenols incluae phenol itself, resorcinol, alXyl-
substituted phenols, such as cresols, xylenols and
tertiary butyl phenols, aryl substituted phenols,
especially p-phenylphenol, and halophenols.
The aldehyde which i5 condensed with the
phenol i5 preferably formaldehyde, but other aldehydes
such as acetaldehyde and furfuraldehyde may also be used.
Pre~erably, the novolaks haYe the general formula
oR' oRI ~R~
~l ~ C
(~)~ (R)h,, . ( R)~,
and may be the same or different,
where m represents ~ero, l, 2, or 3.
the groups R, which may be the same or different, each
represen1;s an alkyl group especially of 1 to 4 carbon
atom , ~ aryl ~roup, e~pecially a phenyl group, a halogen
. : i i . ... . . .
:
13
atom, especially a chlorine atom, or a hydro~y group,
The Rl group~ each represent hydrogs~, an alkyl group
o~ l to 4 carbon atoms or a glycidyl group.
n represents a number o~ a~erage ~alua
1 to 12, and the methylene linkage~ are ortho and/or para
to the OR groups.
Particularly preferred are no~olaXs of formula I in
~hich m represents zero, those in which m represents 1 or 2
and R represent~s an alkyl group of 1 to 4 carbon atoms, a
phenyl grOllp~ or a chlorine atom and Rl represents hydrogen.
Also preferred are novolaks of formula I in which n has an
average ~alue of from 1 to 5.
It i~ ~ell Xnown that unless special purification
procedures are adopted, novolaXs Are comple~ mixtures of
products of various molecular weights, and some components
cannot ~e separated from other components on a preparati~e
scale. For this reason n is defined in terms of its
average value. In any particular product, howe~er, the
average ~alue is made up of a range of ~alu~s. A~ average
value o~ n as 4, for example, has been shown to be made up
o~ species in ~hich n has the value from 1 to 11.
When an oligomer or ~oYolak is present with the phosphate,
the weight ratio of phosphate to oligomer or no~olaX may be
from 1:5 to 50:1. Preferably the ratio is from 1:1 to 25:1
and more preferably from 3:1 to 15:1.
Examples of other ingredients which may be
present in the composi~ions of the in~ention are:
heat ~tabil:i~er~9 light ~tabilisers, W absorbers,
antioxidants, filler~, pigment~, lubricants9
additi~es to improve mold relea~e, fungicides,
,
~3ti3~
- 14 -
blowing agents, optical brightening agents, other fire retardant
additives or other processing aids. Suitable antioxidants include the
sterically hindered phenol compounds for example: 2,2'-thio-bis-(4-
methyl-6-tert. butylphenol), 4,4'-thic)-bis-(3-methyl-6-tert.butyl-
phenol), 2,2'-methylene-bis(4-methyl-6-tert. butylphenol), 2,2'-bls-
~4,4'-phenylol) propane, 2,2'-methylene-bls-(4-ethyl-6-tert.butyl-
! phenol), 9,4'-methylene-bis-(2-methyl-6-tert.butyl-phenol), 4,4'-butyl-
idene-bis-~3-methyl-6-tert.butylphenol), 2,2'-methylene-bist4-methyl-
6-(a-methyl-cyclohexyl)-phenol], 2,6-di(2-hydroxy-3-tert.butyl-5-
methylbenæyl) 4-methyl-phenol, 2,6-di-tert.butyl-4-methylphenol,
1,1,3-tris-(2-methyl-4-hydroxy-5-tert.butyl-phenyl)-butane, 1,3,5-
trimethyl-2,4,6-tri(3,5-di-tert.butyl-4-hydroxy-benzyl)-benzene,
esters of ~-4-hydroxy-3,5-di-tert.bu-tylphsnyl-propionic acid with
monohydric or polyhydric alcohols, such as methanol, ethanol,
octadecanol, hexanediol, nonanediol, thiodiethylene glycol, trimethyl-
olethane or pentaerythritol, 2,4-bis-octylmercapto-6-(4-hydroxy-3,5-di-
tert.butylanilino)-s-triaæine, 2,4-bis-(4-hydroxy-3,5-di-tert.butyl-
phenoxy)6-octylmercapto-s-triazine, 1,1-bis(4~hydroxy-2-methyl-5-tert.
butyl phenyl)-3-dodecyl-mercapto~butane, 2,6-di-t-butyl-p-cresol,
2,2-methylene-bis(4-methyl-6-t-butylphenol),4-hydroxy-3,5-di-
tert.butylbenzyl-phosphonic acid esters, such as the dimethyl,
diethyl or dioctadecyl ester, (3-methyl-4-hydroxy-5-tert.butyl benzyl)-
malonic acid dioctadecyl ester, s-(3,5-dimethyl-4-hydroxy-
phenyl)-thioglycollic acid octadecyl es-ter, and es-ters
r~
- : ~: '. ' " ' -
~lL13~3~7
- 15 -
oE bis-(3,5-di-tert.butyl-4-hydroxyben~.yl)-malonic acid, such as the
didodecyl ester, the dioctadecyl ester and 2-dodecyl-mercaptoethyl
ester.
Suitable llght s-tabilisers and uv ab.sorbers include: sterically
hindered cyclic amines of the formula
'--\C/
I
~ Y
--~C~ q
and salts thereof in which q is 1 or 2, X represents an organic
grouping which complements the nitrogen-containing ring to give a
5-membered, 6-membered or 7-membered ring, Rl and R2 represent methyl
or together represent -~CH2)5-, R3 represents methyl, Rq represents
alkyl with 1 - 5 carbon atoms or together with R3 represents the
2 4 ~ (CH2)5 , -c~l2-c(cH3)2-NH-c(cH ) -CH - or
-CH2-C(CE13)2-N(o )-C(CH3)2-CH2- and, iE q is 1, Y denotes
hydrogen, -0 , hydroxyl, alkyl, substituted alkyl, alkenyl,
aIkynyI, araIkyI, substituted arlalkyl or acyl or, if q
", . j, ! ~ ., '~! ~ . .
3~i ;3~7
- 16 -
is 2, Y denotes alkylene, alkeny].ene, alkynylene, cycloalkylene or
aralkylene.
Examples of sterically hinderecl cyclic aMines o~ formula I
are 4-benzoyloxy-, 2,2,6,6-tetramethy].piperldine; 4-capryl-
oyloxy-,2,2,6,6-tetramethylp~eridine; 4-stearoyloxy-,2,2,6,6-tetra-
methylpiperidine; bis-(2,2,6,6-tetrame-thyl-4-plperidyl)-~ebacate~ bis-
(2,2,6,6~tetramethyl-4-piperidyl)-dodecanediote and bis-(1,2,2,6,6-
pentamethyl-4-piperidyl)-sebacate.
2-(2'-Hydroxyphenyl)-benætriazoles, such as for example, the
5'-methyl-, 3',5'-di-ter~.butyl-, 5'-tert.butyl-, 5'-~1,1,3,3-tetra-
methylbutyl)-, 5-chloro-3',5'-di tert.butyl-, 5-chloro-3'-tert.butyl-
5'-methyl-, 3'sec.butyl-5'-tert.butyl-, 3'-~-methylbenzyl-S'-methyl-,
3'-~-methylbenz.yl-5'-methyl-5-chloro-, 4'-hydroxy-, q'-methoxy-,
4'-octoxy-, 3',5'-di-tert.amyl-, 3'-methyl-5'-carbomethoxyethyl- and
5-chloro-3',5'-di-tsrtO-amyl-derivative.
2,4-Bis-(2' hydroxyphenyl)-6-alkyl-s-triazines such as ~or
example, the 6-ethyl-, 6-heptadecyl- or 6-undecyl-derivative.
2-Hydroxy-benzophenones, such as for example, the 4-hydroxy-,
4-methoxy-, 4-octoxy-, 4-decyloxy, 4-dodecyloxY-, 4-benzyloxy-,
4,2',4'-trihydroxy- or 2'-hydroxy-4,4'-dimethoxy-derivative.
, ~
l~3-Bis-(2~-hydroxybenzoyl)-benzenes such as,~or example,
;~ I,3-bis-(2'-hydroxy-4'-hexyloxy-benzoyl)-benzene, 1,3-bis-(2'-
hydroxy-4'-octyloxy-benzoyll-benzene and 1,3-bis-(2'-hydroxy-4'-
dodecyloxy-benzoyl)-benzene.
'X
- . . .. . .
. ::::: . : :
.. :
~3i~
- 17 -
Esters of op-tionally subs-titutecl ben~oic acids, such as, for
example, phenyl salicylate, octylphenyl salicylate, diben~oylresorcinol,
bis-(4-tert.-butylbenzoyl)-resorcinol, benzoylresorcinol and 3,5-di-
tert.~butyl-4-hydroxybenzoic acid 2,4-di-tert.butyl-phenyl ester or
octadecyl ester or 2-methyl-4,6 di-tert.butyl-phenyl ester.
Acrylates, such as, for example, ~-cyano-~,p-di-phenylacrylic
acid ethyl ester or isooctyl ester, a-carbomethoxycinnamic acid
methyl ester, a-cyano-~-methyl-p-methoxy-cinnamic acid methyl ester or
butyl ester and N-(~-carbomethoxy-vinyl)-2-methyl-indoline.
Oxalic acid diamides, such as, for example, 4,4'-di-
octyloxy-oxanilide, 2,2'-di-octyloxy-5,5'-di-tert.butyl-oxanilide,
2,2'-di-dodecycloxy-5,5'-di-tert.butyl-oxanilide, 2-ethoxy-2'-ethyl-
oxanllide, N,N'-bis-(3-dimethylaminopropyl)-oxalamide, 2-ethoxy-5-
tert.butyl-2'-ethyl-oxanilide and lts mixture uith 2-ethoxy-2'-ethyl-
5,4'-di-tsrt.butyl-oxanilide and mixtures of ortho- and para-methoxy-
as well as of o- and p-ethoxy-disubstituted oxanilides.
~ .
Nickelcompounds, such as , for example, nickel complexes
of 2,2'-thio-bis-[4-(1,1,3,3-tetramethylbutyl)-phenol], such
as the 1:1 or 1:2 complex, optionally with additional
ligands such as n-butylamine, triethanolamine or N-cyclo~
hexyl-diethanolamine, nickel complexes of bis-[2-
; .. , . ~ ~ . : ,; : -: : .
. ~ ., : - :. . : :; -. . ,; , ....
.. : ~ , : , ; .: ,,, , ., .:
1~3Ei3~7
- 18 -
hydroxy-4-(1,1,3,3-tetramethylbutyl)-phenyl]-sulphone, such
as the 2:1 complex, optionally with additional ligands such as
2-ethyl-caproic acid, nickel dibutyldithiocarbamate, nickel salts of
4-hydroxy-3,5-dl-tert.butylben~yl-phosphonic acid monoalkyl esters,
such as the methyl, ethyl or butyl ester, nickel complexes of
ketoximes such as of 2-hydroxy-4-methyl-phenyl-undecylketonoxirne and
nickel 3,5-di-tert. butyl-4-hydroxy-ben~oate.
Phosphate estersoE the present invention and other ingredlents,
if used, may be incorporated into the polymer by any of the usual
procedures. For example, the polymer granules may be dry-blended with
the phosphate in a high speed mixer and the dispersion fed to a
compounder-extruder for melt-blending and finally granulating.
Altsrnatively, the phosphate may be added to the monomer(s) before
or during the polymerisation process. The compositions may be used
to form flbres, molded articles and the like in accordance with
conventional practice.
The phosphate esters described in the invention may be prepared
by known methods. For example, the approprLate phenols may be
reacted with a phosphorylating agent. The phosphorylating agent may
be, for example,phosphorus oxychloride or phosphorus pentachloride.
The phosphorylation reaction may be performed in
the presence of a catalyst, such as aluminium
' .:. ; . . `:
... .
:: : . : . :
::. : . . :
3~;3~7
-- 19 --
chloride or magnesium chloride, or in the presence of an
organic base, such as pyridine. Phosphates may also be
prepared by reacting the sodium salt of the phenol with
the phosphorylating agent or by oxidising the corresponding
phosphorous acid esters by kno~rn procedures.
The following illustrates more fully how phosphate
esters of the present invention may be prepared.
81 parts of 2,6-dimethyl phenol were dissol~ed in
739 parts of chloroform. Phosphorus pentachloride was
then added to the stirred solution over 1 hour at room
temperature until no more would dissolve
Approximately 100 parts of phosphorus pentachloride
were added. The solut on was then filtered and
evaporated to dryness on a rotary evaporator at 90C.
under water pump vacuum. ~ small amount of ethanol was
cautiously added to the solid residue and when the
exothermic reaction had ceased the crude product was
recrystallised twice from aqueous ethanol. The product
was dried in a vacuum o~en at 50C. to give 54 parts
of tris (2,6-dimethylphenyl) phosphate, a white solid,
melting point 136- 138oc.
The product may also be made by the following route:
384 Parts of 2,6 xylenol and 1.3 parts of aluminium
chloride were heated with stirring to 90C. and 153.5 parts
of phosphorus oxychloride added o~er 1 hour. During the
~113~3~)r7
- 20 -
addition the reaction temperature was gradually increased
rrom 90 to 120C. The reaction ~ixture was then heated
to 200C. o~er 4 hours and stirred for 5 hour at 200C.
The temperature wa~ then increa3ed to 250C. o~er 1 hour
~nd the reaction mixture stirred for 8 hour~ at 250C.
The crude product was ~tirred ~or 1 hour at 160C.
under water pump ~acuum and then fractlonally distilled
under high va~um. The fraç,tion boiling between 200C.
and 202C. under a vacuum of 0.2 mm. mercury wa~ coll~cted
to gi~e ~38 parts of tris (2,6 dimethylphenyl) phosphate,
which solidified to a white solid9 melting point
13~ - 136~C.
~ .
488 parts of 2,6-dimethylphenol were added to a
stirred mixture o~ 307 parts of phosphorus oxychloride
and 4 parts of aluminium chloride over 2 hours at
110C. The reaction mixture was heated for 2 hours
at 140C. and then fractionally distilled to give
374 parts of bis (2,6-dimethylphenyl) phosphochloridate,
boiling point 180C. at 0.4 mm. Hg. The intermediate
solidifies to a white solid, melting poi~t 44 - 45C.
243 parts of the abo~re phosphochloridate, 78 parts
of phenol and 1 part of aluminium chloride were heated
to 240C. over 5 hours and then for a further 5 hours
at 240C. The reaction mixture was fra.ctionally
~"' ' ~ " 'I'
::: , :
~:
1~1 3~30r,~
- 21 -
distilled to give 273 parts of bis (2,6-dimethylphenyl)
phenyl phosphate, a colourless liquid, boiling point
210C. at 0. 5 mm. Hg.
To a reaction vessel fitted with stirrer,
thermometer and reflux condenser was charged 540 parts
of naphthalene, 382 parts of paraformaldehyde, and
900 parts of 42. 5% w/w aqueous sulphuric acid. The
reaction mixture was heated and stirred at 105C. for
three hours and allowed to cool to 60C. 600 parts of
water and 1480 parts of chloroform were added, the
mixture stirred for 15 minutes at room temperature, and
then transferred to a separating funnel. The upper
aqueous acid layer was discarded. The lower organio
layer was washed five times with 750 parts o~ cold
water. Chloroform was removed from the crude product
by heating it to 100C. at 20 mm. mercury pressure.
500 parts of water was added and unreacted naphthalene
removed by steam distillation. ~inally, the product
was dried by heating it at 120C. under nitrogen for
2 hours at 20 mm. mercury pressure.
The product was obtained as 509 parts of a brown
plastic solid, softening temperature 50 - 65~C.,
molecular weight = 500.
The Iollowing Examples further illustrate the
invention.
'
.. . . ..
36~C
- 22 -
Examples 1 to 11
The compositions shown in Table I were prepared
by mi,~ing 100 parts of the poly-2,6-dimethyl-1,4-
phenylene oxide/high impact polystyrene poly blend sold
B under the Trade ~ ~ Noryl :L10-780 with 10 parts of
phosphate for 10 - 15 minutes at 240C. followed by
pressing for 10 minutes at 245C. to give a 3 mm.
sheet of test sample. Examination of Table I shows
that compositions of the invention have lower burn times
than the comparative Example A.
The burn time was measured usi~g the "Test for
Flammability for Plastic ~aterials - UL-94" Sept. 17, 1973.
The test i9 carried out on test specimens 6 x ~ x 1/8 inch.
When other sample thicknesses are used the stated
thickness is given.
The test specimen is supported from the upper end,
with longest dimension vertical, by a clamp on a ring
stand 50 that the lower end of the specimen is three-
eighths inch above the top of the burner tube. The
burner is then placed remote from sample, ignited, and
adjusted to produce a blue flame~ three-fourths inch
in height.
The test flame is placed centrally under the lower
end of the te~t ~pecimen and allowed to remain for
10 seconds. The test flame is then withdrawn, and the
duration of flaming combustion of tha specimen noted.
~ , ~ . . . .
- : . : . .
~L~3~
- 23 -
The average of five such burn times is ta~en.
If the specimen drops flaming particles or
droplets while burning in this test, this is noted.
In Table II the effect o~ adding phosphates of
the invention and a naphthalene oligomer i~ sho~n using
a 1.5 mm. polymer sheet. It can be seen that low burn
times ara achie~ed coupled with no dripping of the
sample.
In Table III the effect of phosphate, oli~omer and
calcium carbonate ~iller i9 demonstrated using a 1.5 m~.
polymer sheet. Examples 6, 7 and 8 have low burn times
coupled with no dripping.
In Table IV the effect o~ phosphate and oligomer is
shown on a 1.5 mm. sheet of a polyphenylene oxide/
high impact polystyrene polyblend sbld under the Trade
B ~ Noryl 731-604- Examination of Table IV shows
that low burn times and no dripping is achie~ed.
"
.
Phos- Burn
ExampleCompound phate time
No.~ part 9
A Tri-mesityl phosphate 10 17.8
1 Bis~2,6-dimethyl phenyl) 10 12.0
phenyl phosphate
2 tris(2,6-dimethyl phenyl~ 10 7.4
phos hate I L
:
'
,. , . , ,., . ., . ; ,
,. ~ . . .,. .. ,, ~ . ;.
~3~30 7
- 24
Table II. Flame Retardant Noryl 110-780 ~ith ~hosphate
and na~h~ ~e ~58~
. - Parts Parts _ __ _
Example Phosphatephos- of time
omer
4 Tris (2,6- 18 6 5.8 No
dimethyl phenyl).
phosphat~
.~ 15 6 10.8 No
~ None _ _ ~ 3 Yes
Table III. Flame Retardant Noryl 110-780 with phosphate.
_' ~
. - - Parts .
Example Phosphate. of Burn
No. (parts) ~iller olig- time
----_E~ omer (secs) ~
6 ~ono (2,6- 6 6 6.3 No
dimethyl phenyl)
diphenyl
phosphate (18)
7 tris (~,6- 6 6 4.3 No
dimethyl phenyl)
phenyl phos-
phate (18)
8 Bis (~ t 6- 6 6 6.6 No
dimethyl phenyl) .
phosphate ¦18)
C None _ ~3 Ye~
:~
:.
'
~3~
- 25
and naphthalene oligom0r
Example _ . Olig- time
No, (parts) ,
__ _ __ __ __ __ ___ parts ~seos) Drips
9 phenyl) 3 5.5 No
phosphate (10)
Bis (2,6-dimethyl 3 7.4 No
phenyl) phen~l
phosphate (10)
11 " (12) 1 6.5 No
The compositions shown in Table V were made by mixing
100 parts of the poly-2,6-dimethyl-1,4-phenylene oxide/
high impact polystyrene polyblend sold as Noryl 731-604
with the other ingredients listad and the composition
was then formed into sheets 1.5 mm. thick. The burn
time was measured using the "Test for Flammability for
Plastics Materials -Ul94", September 17, 1973.
The additi~es used were tris(2,6-dimeth~lphenyl)
phosphate and the novolak was one o~ the a~erage formula
OH O t~
~C H,,
'`' `'"':' '~ ' ,
~3~3~d~
- 26 _
TABLE V
. _ ~ ~ _ _
Parts ~ Burn He~t
Example Phos- Parts Time Oxygen Distortion
No-__ ~ Novolak ~ ecs. ~ Index
D None None HEI 22.0 127
12 lZ None 12.0 29.8 97
-13 12 1 VE 30.2 98.1
14 10 3 VE 1 31 6 99
It can be seen that the burning performance of the
polymer i~ improved by the addition of the phosphate~ and
that the performance is further improved by the addition of
the novolal~.
The composition~ shown in Table VI were made by mixing
100 parts of Noryl 731-604 with the other ingredients and
the composition was then formed into sheets 4 mm. thick.
The Xeat Distortion Temperature was then measured.
TABLE VI
Example Phosphate (parts) Distortion
No. Tem~. C.
. ._
; E tripheny phosphate 82
tris (2,6 dimethyl phenyl)
phosphate (12) 97
~; ~ ,,,, . _ ~
It can be seen that the Heat Distortion Temperature
of Example 15 is improved considerably over comparative
Example E containing triphenyl phosphate.
,
,, . A ~ ~
`J ' p `
- ' - '` . ' '; .
,,
