DE3121067A1 - "FIRE-RETARDANT THERMOPLASTIC MOLDS" - Google Patents

Description

Fire-retardant thermoplastic molding compound

The term "polyphenylene ether resin" refers to a well-known group of polymers formed by a variety of
can be produced by catalytic and non-catalytic processes, as for example in the US-PSs 3 219 626, 3 257 »357, 3 257 358, 3 306 874, 3 306 875,
3,337,499, 3,356,761, 3,382,212, 3,384,619, 3,440,217,
3,442,885, 3,455,880 and 3,573,257.

US Pat. No. 3,383,435 describes formulations of polyphenylene ether resins and styrene resins, including halogenated styrene resins. In US Pat. No. 3,687,646, preparations are disclosed which contain polyphenylene ether resin and a chlorostyrene resin. U.S. Patent 3,629,506 describes formulations of a polyphenylene ether resin containing styrene resins, phosphates and halogenated fire retardants. The disclosure content of all patents and publications mentioned in this specification is indicated by this reference in
incorporated in full in the present application.

It has been found that the preparations from a polyphe-

* ■ 1 W *

ethylene ether resin and a copolymer of styrene-bromostyrene better ultraviolet light stability compared to Preparations which contain brominated additives of low molecular weight indicate that they are inherent in their nature after are fire retardant and little or no additional fire retardant to achieve an acceptable level of fire retardancy Need additive. It was also found that the copolymers of styrene-bromostyrene with polyphenylene ether resins compared to 100% bromostyrene polymers, which show phase separation when combined with polyphenylene ether resins are compatible. It was determined, that an 85: IS-bromostyrene / styrene copolymer as 75:25 preparation of polyphenylene ether: bromostyrene copolymer It is possible to use a preparation of 50:50 polyphenylene ether: bromostyrene copolymer of either 85:15 or bromostyrene: styrene copolymer or the polymer of Bromostyrene alone forms two phases. A 70:30 bromostyrene: styrene copolymer is made with polyphenylene ether resins in all proportions like all bromostyrene copolymers that contain less than 70% bromostyrene, compatible. The same degree of compatibility for the bromostyrene-styrene copolymer is expected at the lower end of the concentration range.

The preparations containing the bromostyrene copolymer can be extruded and pressed without discoloration. They have a higher dimensional stability as well as a better one Resistance to combustion as analogous polyphenylene ether resin preparations, made with polystyrene.

It has been found that the bromine, if in the styrene-bromostyrene copolymer is present, is more effective as a fire retardant than an equivalent amount of bromine, which than

low molecular weight fire retardant added to analog polyphenylene ether-styrene resin formulations will.

It was also found that bromine in the form of a bromostyrene-styrene copolymer counteracts the degrading effects of ultraviolet radiation compared to a low molecular weight compound containing bromine, such as decabromodiphenyl ether, is more stable when tested in the presence of a polyphenylene ether resin. In addition, was found that preparations made from a polyphenylene ether resin and a copolymer of styrene-bromostyrene compared discoloration by ultraviolet light are more stable than preparations made from a polyphenylene ether and a homopolystyrene.

The preparations of the present invention contain characteristically

(a) a polyphenylene ether resin, and

(b) a copolymer of styrene-bromostyrene.

The polyphenylene ether resins contain polymers with structural units the following general formula

wherein Q from the group consisting of hydrogen, hydrocarbon radicals, Halocarbon radicals with at least two carbon atoms between the halogen atom and the Phe-

nyl nucleus, hydrocarbonoxy radicals and halohydrocarbonoxy radicals with at least two carbon atoms is selected between the halogen atom and the phenyl nucleus, Q 'and Q "have the same meaning as Q and are also halogen with the proviso that both Q and Q ¹ do not contain a tertiary carbon atom, and the Index η is an integer with a value of at least 50.

The preferred polyphenylene ether resin is a poly (2,6-dimethyl-1,4-phenylene) ether resin having an intrinsic viscosity (I.V.) of about 0.40 dl / g to about 0.60 dl / g, measured in Chloroform at 30 ° C.

The copolymers of styrene-bromostyrene can be made from styrene and Bromostyrene can be produced. In addition, isomeric mixtures of bromostyrene can be used, the p-, m- and Contain o-bromostyrene. In general, the weight ratio from styrene to bromostyrene in the copolymer from 15:85 to 85:15, and more preferably from 30:70 to 85:15 vary.

There can be from 80 to 10 parts by weight of the copolymer of styrene-bromostyrene together with 20 to 90 parts by weight of the Polyphenylene ether resin are used. These copolymers can be prepared by various methods known to those skilled in the art are well known, including free radical polymerization, bulk polymerization, suspension polymerization and emulsion polymerization processes. These copolymers were made by Makhteshim Chemical Co. obtained as copolymers containing 26.6 percent by weight bromine and 30.4 percent by weight bromine.

From 1 to 15 parts by weight of a thermoplastic rubber,

_ 7 -

such as an ABA or AB block copolymer, can can be used in the preparations according to the invention. Suitable ABA block copolymers are the Kraton or Kraton-G polymers, which are described in US Pat. Nos. 3,646,162 and 3,595,942.

If desired, reinforcing amounts of reinforcing fillers can be added to the preparations in amounts ranging from 5 to 40 percent by weight, based on the total preparations, are added. Glass fibers or other reinforcing agents, such as quartz, mica, wollastonite or carbon fibers can be used as reinforcing fillers.

When the amount of bromine in the formulations of the present invention is insufficient to achieve the desired level To achieve fire retardancy, a smaller amount of a phosphorus compound, i.e. 0.1 to 7.5 parts by weight of a Phosphorus compound, calculated as elemental phosphorus per 100 parts by weight of the total preparation, can be added.

In general, the preferred phosphorus compounds can be made from elemental phosphorus or organic phosphonic acids, Phosphonates, phosphinates, phosphonites, phosphinites, phosphine oxides, phosphines, phoaphites and phosphates be. This is illustrated by triphenylphosphine oxide. This can be used alone or with antimony oxide.

Typical of the preferred phosphorus compounds which can be used in the present invention are those the following general formula

Il

QO-ρ-OQ OQ

in which each radical Q is the same or different radicals including hydrocarbon radicals, such as alkyl, cycloalkyl, Means aryl, alkyl-substituted aryl and aryl-substituted alkyl, halogen, hydrogen, and combinations thereof, provided that at least one of the radicals Q is an aryl radical. Typical examples of suitable phosphates include Phenyl bisdodecyl phosphate, phenylethyl hydrogen phosphate, fithyldiphenyl phosphate, 2-ethylhexyl di (p-tolyl) phosphate, diphenyl hydrogen phosphate, Tricresyl phosphate, triphenyl phosphate, 2-chloroethyldiphenyl phosphate and diphenyl hydrogen phosphate. The preferred phosphates are those that are commercially available, such as Kronitex-50, the one Mixture of isomers of tri-isopropylphenyl phosphate is.

The formulations can be made by tumbling powders, beads, or extruded pellets of the components with or without suitable reinforcing agents, stabilizers, pigments, non-reinforcing fillers, e.g. 5 to 50%, based on the total weight of the preparation, of clays, talc, etc., added fire retardants, plasticizers or extrusion aids. The preparations can by extrusion of the constituents into one continuous strand, chopping the strand into pellets and compressing the pellets into any desired shape, ***" getting produced.

example 1

Preparations of 65 parts of poly (2,6-dimethyl-1,4-phenylene) ether (IV = 0.47 dl / g in CHCl ₃ at 30 ⁰ C), 35 parts of a styrene-bromostyrene copolymers with a content of 27 % bromine, 10 parts hydrogenated styrene-butadiene-styrene block copolymer (Kraton G 1652), 3 parts titanium dioxide, 1.0 part diphenyldecylphosphite, 0.15 part zinc sulfide, 0.15 part

Zinc oxide and 1.5 parts of polyethylene were extruded and pressed into standardized ASTM test specimens. For comparison became a mixture of the same composition, but with homopolystyrene (Dylene 8G) instead of the bromostyrene copolymer extruded and molded in a similar manner. The properties of the mixtures are in the table below I stated. The blend containing the bromostyrene copolymer had approximately the same gloss, tensile strength values and impact strength like the mixture with the styrene homopolymer, but a much higher dimensional stability and much better flame retardant properties.

Table I.

Mixed with
Polystyrene
Homopolymer Mixed with
Bromostyrene
Copolymer 5.1 strain 29 33 Tensile Yield Strength ₍ ^ba £ v 537.8
(7800) 565.4
(8200) Tensile strength *** 517.1
(7500) 551.6
(8000) Izod punch (ft.lbs / in. notch) 5.1 4.7 Gardner shock (in.lbs) 225 215 Gloss (45 °) 62.0 61.3 Yellow index 23.2 18.7 Or
Dimensional stability _ok p. 137.2
(279) 145.6
(294) UL-9 4 rating Failed, V-1 drips Average
Burn time 53

Examples 2 to 4

Formulations comprising 85 parts of poly (2,6-dimethyl - 1,4-phenylene) ether with an intrinsic viscosity of 0.54 dl / g in CHCl ₃ at 30 ⁰ C, 15 parts of the styrene-Bromstyrol- described in Example 1 Copolymers, 5 parts of the hydrogenated block copolymer (Kraton G 1652), 3 parts of titanium dioxide, 1 part of diphenyldecyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide and 1.5 parts of polyethylene were extruded and pressed as described in Example 1. For comparison, a mixture of the same composition, but with the polystyrene homopolymer Dylene 8G instead of the bromostyrene copolymer * ■ ***, was extruded and pressed in a similar manner.

Mixtures of the same preparation, but with the addition of 3 parts triphenyl phosphate, were prepared in the same way, using the same batch of poly (2,6-dimethyl-1,4-phenylene) ether and a mixture with poly ( 2,6-dimethyl-1,4-phenyl) ether of low molecular weight (IV = 0.37 dl / g in CHCl ₃ at 30 ° C). The properties of these blends are given in Table II below. Mixtures containing the styrene-bromostyrene copolymers had approximately the same tensile strength, impact strength, gloss and color as mixtures of the same compositions. composition made with polystyrene homopolymers, however, better dimensional stability and much better flame retardant properties. The 85:15 formulations containing the bromostyrene copolymer had good burn resistance (V-1 rating by UL-94) without any added fire retardant, but this was further improved by the addition of 3 parts triphenyl phosphate (V-0 rating).

Table II

Accessories
rei
tion
No. IV
Poly-
(2.6-
dimethyl
1,4-pheny-
len) ether Poly
styrene Tri-
phenyl
phosphate Deh
tion
(%) TY
bar
(psi) train
firm
speed
bar
(psi) Izod
(ft.
lbs /
in) Gardner
(in.
lbs.) yellow
index shine
(45O) shape
persist
age
OC
(op) ÜL94 By
schnittli
che focal
time (S) A. 0.54 Bromine-
styrene
Copoly- None 23 744.6
(10800) 599.8
(8700) 3.5 5 30.6 55.5 170.6
(339) V-1 3.1 meres B * 0.54 Poly
styrene None 23 737.7
(10700) 599.8
(8700) 3.9 15th 32.4 61.1 163.9
(327) not
passed 24.6 C. 0.54 Brcm-
styrene
Copoly-
meres 3 TIe. 24 744.6
(10800) 599.8
(8700) 3.5 20th 31.1 62.6 163.9
(327) V-O 2.6 D * 0.54 Poly
styrene 3 TIe. 29 730.8
(10600) 551.6
(8000) 3.1 20th 33.9 60.9 157.8
(316) V-1 12.9 E. 0.37 Bram-
styrene 3 TIe. 36 758.4
(11000) 482.6
(7000) 1.9 125 31.2 62.7 158.9
(318) - V-O 2.5

Control attempt

The molecular weight of the poly (2,6-dimethyl-1,4-phenylene) ether used in the blends with the bromostyrene copolymer can be varied over a wide range with no significant effect on flammability or most other properties, however has been by reducing the intrinsic viscosity of the poly (2,6-dimethyl-1,4-phenylene) ether from 0.54 to 0.37 dl / g, measured in CHCl ₃ at 30 ° C., the Izod impact strength is reduced and the Gardner impact strength is greatly increased.

For games 5 to 7

A mixture of 75 parts of poly (2,6-dimethy1-1,4-phenylene) ether, 25 parts of the bromostyrene-styrene copolymer, 10 parts of hydrogenated styrene-butadiene copolymer (Kraton G 1652), 3 parts titanium dioxide, 1 part diphenyl decyl phosphite, 0.15 Parts of zinc sulfide, 0.15 parts of zinc oxide and 1.5 parts of polyethylene were extruded and described as in Example 1, pressed. Another mixture of the same composition was also made with the addition of 3 parts of triphenyl phosphate produced, and for comparison mixtures of the same composition, the bromostyrene copolymer by polystyrene homopolymer (Dylene 8G) had been replaced.

Other mixtures were prepared as described above. using polystyrene (Dylene 8G) with the addition of sufficient decabromodiphenyl ether to achieve the percentage of bromine, based on poly (2,6-dimethyl-1,4-phenylene) -ether and polystyrene alone den. same as in the mixtures with the bromostyrene copolymer, and others with a little more deodorant diphenyl ether, so that the percentage Bromine based on the total weight of the blend was the same as the blends with the bromostyrene copolymer. The properties of the mixtures are given in Table III below. The mixtures containing the bromostyrene

Left part

Tabel

III

Accessories
rei
tion
No. Bromine-
styrene
Copoly-
meres Styrene
homo-
polymer-
To do this *
(Parts) Tri-
phenyl
phosphate Deca-
bromine-
diphe-
nylon
ether strain
(%) TY
bar
(psi) tensile strenght
bar
(psi) F.
G
H**
I **
J **
K **
L **
M ** 25th
25th
None
None
None
None
None
None No
No
25th
25th
25th
25th
25th
25th None
3 parts
None
3 parts
None
None
3 parts
3 parts No
No
No
No
8.1
8.8
8.1
8.8 41
42
32
40
37
37
36
33 572.3
(8300)
565.4
(8200)
551.6
(8000)
551.6
(8000)
586.1
(8500)
586.1
(8500)
586.1
(8500)
586.1
(8500) 524.0
(7600)
530.9
(7700)
524.0
(7600)
510.2
(7400)
579.2
(8400)
579.2
(8400)
565.4
(8200)
579.2
(8400)

* Each mixture also contained 75 parts of poly (2,6-dimethyl-1,4-phenylene) ether, 3 parts of titanium dioxide, 1 part of phenyldecyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide, 1.5 parts of polyethylene and 10 parts of hydrogenated styrene-butadiene block copolymer Kraton G 1652.

** Control! Attempt

CD CT)

Table III

Right part

Accessories
rei
tion
No. Izod
(ft.
Ib /
in) Gardner
(in/
Ib) shine
(45O) Yellow index shape
persist
age
° C
( ⁰ F) Enamel
viscosity
Pa.s 287 ° C
(Poise 548 ° F) UL94
valuation By
schnittli
che focal
time (s) F.
G
H**
j ##
J **
K **
L **
M ** 13.4
17.6
11.4
18.0
5.9
5.3
4.8
6.2 100
200
225
225
175
200
150
250 62.1
61.4
59.1
59.7
59.2
37.7
58.2
58.0 23.02
22.68
24.60
24.60
26.40
28.40
27.80
28.90 148.0
(300)
147.2
(297)
147.2
(297)
140.0
(284)
143.3
(290)
145.6
(294)
140.0
(284)
142.2
(288) 450
(4500)
425
(4250) V-1
VO
not
passed
V-1
not
passed
V-1
V-1
V-1 6.2
2.2.
27.1
16.5
14.8
11, 0
8.6
6.9

Control attempt

Containing copolymers have a high dimensional stability and high Izod impact strength. Most of the properties are approximately equivalent to those of the control blends obtained with polystyrene homopolymer, with a somewhat better dimensional stability and greatly improved flammability properties. The one with the bromostyrene copolymer The mixture produced had a V-1 flammability rating with no fire retardant added; the rating improved to V-O, with a very short burning time, with the addition of only 3 parts of triphenyl phosphate.

The same amount of bromine, added in the form of decabromodiphenyl ether, causes an increase in color, a decrease in dimensional stability, and a lower Izod impact strength and is much less effective as a flame suppressant.

Example 8

The mixtures described in Examples 5 to 7 were added to plates with dimensions of 3.175 mm 63.5 mm χ χ 82.55 mm (0.125 inch 2.5 inch χ χ 3.25 inch) pressed. The panels were placed in racks under a sheet of ordinary single thickness window glass on a rotating platform and exposed to a battery of ultraviolet fluorescent lamps at a distance of 76.2 mm (3 inches). Yellowness Index was measured at 24 hour intervals by the method of ASTM Test D1925 with the results reported in Table IV. The formulations containing the low molecular weight additive containing bromine yellowed rapidly (Blends J through M), whereas Blends P and G, which contained the bromostyrene copolymer, actually yellowed slightly less than the mixtures.

gen H ** and I **, which did not contain any form of bromine.

Table IV

Preparation* rise 48 in the yellow index 72 hours P. 24 hours hours 2.8 <? -0.5 1.2 2.8 H** -0.5 1.7 3.7 j ## 0.0 2.1 3.6 j * # 0.1 2.1 37.8 K ** 14.2 32.1 39.2 L ** 15.0 28.6 36.7 M ** 13.0 29.7 37.7 13.7 29.4

* Preparations from Table III ** Control test

Example 9

A mixture of 75 parts of poly (2,6-dimethy1-1,4-phenylene) ether, 25 parts of bromostyrene copolymer, 10 parts of hydrogenated Styrene-butadiene-styrene block copolymer (Kraton G 1651), 3 parts of titanium dioxide, 3 parts of triphenyl phosphate, 1 part Diphenyldecylphosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide and 1.5 parts of polyethylene was as in Example 1 described extruded and pressed. The properties of the preparation are given below:

Elongation (%) 29

Tensile Yield Strength _{ £ jJ _{} (}

Tensile strength £ «

/ ■ * ■ -

example

Izod impact strength (ft.lbs / in) 1.8

Gardner beat (in.lbs) 240

Gloss (45 °) 38.9

Yellow index 24.3

or

Dimensional stability _(O ". 150.6

¹ * ' (303)

UL-94 rating V-O

Average burn time (in seconds) 3.1

Compressed preparations from 75 parts of poly (2,6-dimethyI-1,4-phenylene) ether, 24 parts of a bromostyrene polymer or bromostyrene-styrene copolymer, 3 parts of titanium dioxide, 1.5 parts of triphenyl phosphate and 10 parts of a styrene-butadiene-styrene block copolymer (Kraton G 1651) were produced by extrusion and compression. The preparations had the properties given in Table V below.

Tabel

% Bromostyrene
in the polymer Izod-
Blow Gardner
Blow Average Burn time
UL-9 4 Appearance 70
85
100 * 6.1
8.6
8.0 275
300
15th 1.9
1.7
0.9 Good
Good
Lami
ned

Control attempt

example

11

Compressed preparations made from 60 parts of poly (2,6-dimethy1-1,4-phenylene) ether resin, 40 parts of a bromostyrene polymer or a copolymer of bromostyrene-styrene, 1.5 parts Triphenyl phosphate and 10 parts of a styrene-butadiene-styrene block copolymer were made by extrusion and pressing. The preparations had those in the following Properties given in Table VI.

Tabel

VI

Izod-
Blow Gardner
Blow Average Burn time
UL-94 Appearance % Bromostyrene
in the polymer 5.6 225 2.9 Good 70 4.1 30th 2.0 Lami
ned 85 4.0 5 0.6 Lami
ned 100 *

Control attempt

Comparative example

1000 g of bromostyrene monomer (Makheteshim - 27% ortho, 70% para, 3% meta) were stirred with 0.6 g of azobisisobutyronitrile and 0.6 g of dicumyl peroxide at 82 ° C. under nitrogen. After 6 hours, the product in 1500 ml of water containing 6 g of polyvinyl alcohol and 4.5 g of gelatin was contained, suspended, and the polymerization was continued at 85 ° for 14 hours to 100 ⁰ C. Mixtures with poly (2,6-dimethyl-1,4-phenylene) ether were prepared by coprecipitation from toluene in methanol and the mixtures were pressed into films to determine the glass transition temperature.

% Poly (2.6-
dimethyl-1,4-
phenylene) ether T _g (1)
(° C) T _g (2)
( ⁰ C) O 131 - 25th 136 208 50 137 206 75 137 209 100 - 211

The mixtures show the presence of two glass transition

-ren

temperatu / what a characteristic of the lack of tolerance this is two materials.

Claims (10)

1, River Road Schenectady, N.Y., U.S.A. claims 1. Fire-retardant thermoplastic molding compound, thereby marked that they are out (a) a polyphenylene ether resin and (b) is a copolymer of styrene-bromostyrene. 2. Preparation according to claim 1, characterized in that the polyphenylene ether resin structural units of the following general formula .Q "Q J η contains, in which Q is selected from the group consisting of hydrogen, hydrocarbon radicals, halogenated hydrocarbon radicals with at least two carbon atoms between the halogen atom and the phenyl nucleus, hydrocarbonoxy radicals and halo hydrocarbonoxy radicals with at least two carbon atoms between the halogen atom and the phenyl nucleus, Q ¹ and Q "have the same meaning like Q and besides Are halogen with the proviso that both Q and Q ¹ do not contain a tertiary carbon atom and the index η is an integer with a value of at least 50. 3. Preparation according to claim 2, characterized in that that Q "is hydrogen. 4. Preparation according to claim 2, characterized in that the polyphenylene ether resin Po-Iy (2,6-dimethyl-1,4-phenylene) ether resin is. 5. Preparation according to one of claims 1 to 4, characterized in that the weight ratio of styrene to bromostyrene is 85:15 to 15:85. 6. Preparation according to one of claims 1 to 5, characterized in that it is from 20 to 90 parts by weight of a polyphenylene ether, and from to about 10 parts by weight of the copolymer. 7. Preparation according to one of claims 1 to 6, characterized in that it further still contains a filler. 8. Preparation according to one of claims 1 to 7, characterized in that it further still contains a phosphate as a fire retardant. 9. Feed line according to one of claims 1 to 8, characterized in that it is marked. i c h η e t that they also still contains a thermoplastic rubber. 10. Preparation according to claim 9, characterized in that that the thermoplastic rubber is an ABA block copolymer.