FR2483444A1 - THERMOPLASTIC COMPOSITION BASED ON POLY (OXYPHENYLENE) RESIN AND STYRENE BROMOSTYRENE COPOLYMER - Google Patents

Abstract

FIRE-RETARDANT COMPOSITION STABLE TO ULTRAVIOLET LIGHT. IT INCLUDES: A. POLY RESIN (OXYPHENYLENE); AND B. A STYRENE-BROMOSTYRENE COPOLYMER. MOLDING APPLICATION.

Description

The term "poly (oxyphenylene) resin" characterizes a group

  well known depolymers which can be prepared by various catalytic or non-catalytic processes, as described, for example, in U.S. Patent Nos. 3,306,874, 3,306,875, 3,257,357, 3,257,358, 3,356,761,

  3,337,499, 3,219,626, 3,384,619, 3,440,217, 3,442,885, 3,573,257,

3,455,880 and 3,382,212.

  U.S. Patent No. 3,383,435 discloses poly (oxyphenylene) resin compositions and

  styrene resins comprising halogenated styrene resins

  embarrassed. U.S. Patent No. 3,887,646 discloses compositions which comprise a polyphenylene oxide resin and a chlorostyrene resin. U.S. Patent No. 3,629,506 discloses poly (oxyphenylene) resin compositions which comprise styrene resins,

  phosphates and halogenated flame retardants.

  It has been found that the compositions of a resin. of poly-

  (oxyphenylene) and a styrene-bromostyrene copolymer exhibit better ultraviolet light stability than compositions containing low molecular weight brominated additives, are inherently flame retarded, and require little or no flame retardant additives to exhibit acceptable fire resistance. It has also been found that styrene-bromostyrene copolymers are compatible with poly (oxyphenylene) resins, when compared with 100% bromostyrene polymers which, when combined with poly (oxyphenylene) resins, phase separation. It has been found that a copolymer of

  bromostyrene: styrene 85:15 is miscible with a

  poly (oxyphenylene) sition: bromostyrene copolymer

  at 75:25, while a 50:80 composition of poly (oxy-

  phenylene): bromostyrene copolymer with a 85:15 styrenebromostyrene copolymer, or a bromostyrene polymer alone, forms two phases. A 70: 30 styrene-bromostyrene copolymer is compatible with poly (oxyphenylene) resins in all proportions, as are all bromostyrene copolymers containing less than 70% bromostyrene. The same degree of compatibility is expected for the bromostyrene-styrene copolymer at the lower end

of the concentration range.

  It is possible to extrude and mold the compositions containing the

  copolymer bromostyrene without changing color.

  They exhibit sagging temperatures under load as well as higher combustion resistance than

  analogous compositions of poly (oxyphenylene) resins

made with polystyrene.

  Bromine, when present in the styrene-bromostyrene copolymer, has been found to be more effective as flame retardant than the equivalent amount of bromine added as a low molecular weight flame retardant in

  similar compositions of poly (oxyphenylene) resins -

  styrene. It has also been found that bromine, in the form of a bromostyrene-styrene copolymer, is more stable to ultraviolet radiation-induced degradation than a low molecular weight compound containing bromine such as decabromodiphenyl oxide. It has also been discovered that the compositions of a poly (oxyphenylene) resin and a styrene-bromostyrene copolymer are more stable to the color change in ultraviolet light than the

  compositions of a poly (oxyphenylene) and a homopolystyrene.

  The compositions of the invention comprise (a) poly (oxyphenylene) resin; and

  (b) a styrene-bromostyrene copolymer.

  the poly (oxyphenylene) resins comprise polymers whose units correspond to the formula:

Q IF QI

Q "Q

  wherein Q is selected from the group consisting of

  hydrogen, hydrocarbon radicals, hydrocarbon radicals,

  halogenated bonbons having at least 2 carbon atoms

  the halogen atom and the phenyl ring, the oxyhydro-

  carbon and halogenated oxyhydrocarbon radicals having at least two carbon atoms between the halogen atom and the phenyl ring, Q 'and Q "I' may represent the same radicals as Q, and in addition a halogen, provided that Q and Q 'both lack a tertiary carbon atom and n represent

  an integer of at least 50.

  The most preferred poly (oxyphenylene) resin is a 2,6-poly (2,6-dimethylphenylphenyl) resin having a viscosity limit of between about 0.40 dl / g.

  and about 0.60 dl / g measured in chloroform at 30 C.

  The styrene-bromostyrene copolymers can be prepared from styrene and bromostyrene. It is also possible to use isomeric mixtures of bromostyrene which comprise para-, meta- and ortho-bromostyrene. In general, the weight ratio of styrene to bromostyrene in the copolymer can vary between 15:85 and 85:15, and will be

  preferably between 30:70 and 85:15.

  From 80 to 10 parts by weight of the styrene bromostyrene copolymer can be used in combination with 20 to 90 parts by weight of the polyphenylene oxide resin. These copolymers can be prepared by a variety of methods which are well known to those skilled in the art, including

  polymerization in the presence of free radicals, polymeric

  bulk polymerization, slurry polymerization, and emulsion polymerization. These copolymers were obtained from Makhteshim Chemical Co. in the form of copolymers

  containing 26.6% by weight of bromine and 30.4% by weight of bromine.

  From 1 to 15 parts by weight of a thermoplastic rubber, such as an ABA or AB block copolymer, can be used in the compositions of the invention. Among the suitable ABA block copolymers, mention may be made of the Kraton or Kraton-G polymers which are described respectively in the US Pat.

  United States of America Nos. 3,646,162 and 3,595,942.

  If desired, we can add reinforcements

  to the compositions, in an effective amount of between 40% and 40% by weight of the total composition. Glass fibers or other reinforcing agents such as quartz, mica, wollastonite or carbon fibers can be used.

as reinforcing loads.

  If the amount of bromine present in the compositions of the invention does not make it possible to attain the desired degree of fire resistance, a small amount of a phosphorus compound, that is to say 0, can be added. 1 to 7.5 parts by weight

  of a phosphorus compound, calculated as phosphorus

  per 100 parts by weight of the total composition.

  In general, the phosphorus compounds recommended in the group consisting of elemental phosphorus or organic phosphonic acids, phosphonates, phosphinates, phosphonites, phosphinites, phosphine oxides, phosphines, phosphites may be chosen. and phosphates. For example, triphenylphosphine oxide may be used. We can use them alone

or with antimony oxide.

  Amongst the conventional recommended phosphorus compounds which can be used in this invention, the compounds having the general formula:

0

he

QO-P-OQ

  Wherein the Q groups are the same or different and represent radicals from which

  hydrocarbon radicals such as alkyl radicals, cyclo

  alkyls, aryls, aryls substituted with alkyl groups, alkyls substituted with aryl groups, halogens; hydrogen and combinations thereof, provided that at least one of Q is an aryl radical. Suitable conventional examples of suitable phosphates are phenyl bisdodecyl phosphates, phenyl, ethyl and hydrogen phosphate, ethyl and diphenyl phosphate, 2-ethylhexyl phosphate and the like. di (p-tolyl), diphenyl hydrogen phosphate, tricresyl phosphate triphenyl phosphate, 2-chloroethyl diphenyl phosphate, and diphenyl hydrogen phosphate. Among the phosphates, those found in commerce, such as Kronitex-50, which is

  a mixture of isomers of tri-isopropylphenyl phosphate.

  The compositions may be prepared by tumbling extruded powders, beads or pellets of the components with or without suitable reinforcing agents, stabilizers, pigments, non-reinforcing fillers and, for example, 5% by weight of the total weight of the composition. clays, talcs, etco, added flame retardants, plasticizers or extrusion aids. The compositions can be prepared by extruding the components into a continuous base wire, cutting the base wire into pellets and molding the pellets to the

desired form.

Example 1

  Compositions comprising 65 parts of poly (2,2-oxydimethyl-1,4-phenylene) (Viscosity limit index = 0.47 dl / g in CHCl 3 at 30 ° C.) were extruded. 35 parts of a styrene-bromostyrene copolymer containing 27% bromine, 10 parts

  of a block copolymer of styrene-butadiene-styrene hydro-

  gene (Kraton G-1652), 3 parts of titanium dioxide, 1.0 part of diphenyl and decyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide and 1.5 part of polyethylene, and molded in the form of standard ASTM test specimens. For comparative purposes, a mixture having the same composition, but replacing the bromostyrene copolymer with homopolystyrene (Dylene IG) was extruded and molded in the same way. The properties of the mixtures in Table 1. The mixture containing the bromostyrene copolymer exhibited a gloss, tensile strength, and impact strength about the same as the styrene homopolymer-containing mixture, but a significantly higher sag temperature under load and fire resistance properties

much better.

TABLE 1

  Mixture containing Mixture containing the homopolymer of the polystyrene copolymer bromopolystyrene Elongation% 29 33 Tensile yield strength (daN / mm2) 5,374 5,650 Tensile strength r (daN / mm2) 5,168 5,512 Impact strength Izod (joules / cm) notched) - 2.72 2.51 Impact resistance Gardner (joules) 25.42 24.29 Gloss (450) 62.0 61, 3 Yellowness index 23.2 18.7 Bending temperature under load C 137 146 UL Rating 94 Bad (stilling) V-1 Average Burn Time (s) 53 5.1

Examples 2 to 4

  Compositions comprising 85 parts of poly (2,6-oxydimethylphenylene-14) having a viscosity limiting index of 0.54 dl / g in CHCl 3 at 30 ° C. were extruded and molded, 15 parts of the styrene-bromostyrene copolymer described. in Example 1, 5 parts of hydrogenated block copolymer (Kraton G 1652), 3 parts of titanium dioxide, 1 part of diphenyl and decyl phosphite, 0.15 part of zinc sulfide, 0.15 parts of zinc oxide and 1.5 parts of polyethylene, as described in Example 1. For comparative purposes, a mixture of the same was extruded and molded in the same manner.

  composition but containing in place of the brominated copolymer

  styrene, polystyrene homopolymer Dylene 8G.

  Mixtures of the same composition were prepared in the same manner, but 3 parts of

  triphenyl, using the same sample of poly (oxi-

  methyl-1,6-phenylene-1,4), and for a mixture, a poly (oxy-

  1,6-dimethylphenylene-1,4) of low molar mass

  (Limit viscosity index = 0.37 dl / g in CHCl 3 at 30 ° C.).

  The properties of these blends were reported in Table 2. Blends containing the styrene-bromostyrene copolymer showed about the same tensile strength, impact resistance, gloss, and color as blends of the same. composition prepared with a polystyrene homopolymer, but a higher load deflection temperature and fire resistance properties

  much better. The 85:15 composition containing the copo-

  bromostyrene lymere had good fire resistance (UL-94 V-1 classification), without addition of any flame retardant, but was further improved (V-O grading) by addition

  3 parts of triphenyl phosphate.

  The molar masses of poly (2,6-oxydimethyl-1,4-phenylene) used in

  mixtures with the bromostyrene copolymer, without

  have a significant effect on fire resistance or most other properties, but a decrease in the viscosity limit of poly (2,6-oxydimethylphenylene-1,4) from 0.54 to 0.37 dl / g, measured in CHCl 3 at 30 ° C, resulted in a decrease in Izod impact strength, and an increase in

  important of the Gardner impact resistance.

  Comp Limit Index N Polystyrene Viscosity

poly (oxy-

  2,6-dimethyl-1,4-phenylene) A 0.54 copolymer

Bromo-

  styrene BnC 0.54 Polystyrene C 0.54 Copolymer bromo-: styrene D :: 0, 54 Polystyrene

E 0.37 Bromo-

  styrene triphenyl phosphate o o parts parts elongation (M)

TABLE 2

  Resistance Resistance of elasticity. when pulling in tension daN / mm daN / mm2

7.441 5.994

7.372 5.994

7.441 5.994

29 7.303

36 7.579

  , 512 4,823 R6 Izod impact strength (joules / cm) 1.87 2.08 1.87 1.65 1.01 Gardner impact strength (joules) 0.56 1.69 2.26 2.26 14.12 Index Yellowing, 6 32.4 31.1 33.9 31.2 Bright Temperature

(450)

  under load (&)

, 5 - 171

61.1 164

62.6164

, 9,158

62.7 159

  mi UL 94 Average Burn Time (a)

V-I 3.1

24.6

V-O0 2.6

V-1 12.9 o00

V-O 2.5

:: O4 iW witness

Examples 5-7

  A mixture of 75 parts of poly (2,6-oxydimethyl-1,4-phenylene), 25 parts of the bromostyrene-styrene copolymer, 10 parts of styrene-budatiene hydrogen copolymer (Kraton G 1652), was extruded and molded. parts of titanium dioxide, 1 part of diphenyl and decyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide, and 1.5 part of polyethylene, as described in example

  1. Another mixture of the same

  addition of 3 parts of triphenyl phosphate, and for comparative purposes, mixtures of the same composition,

  but replacing the bromostyrene copolymer with a homo-

polymer (Dylene 8G).

  Other mixtures have been prepared as described above.

  previously, using polystyrene (Dylene 8G) and adding a sufficient amount of decabromodiphenyl oxide to obtain the same percentage of bromine, based on poly (2,6-dimethylphenylphenyl) and polystyrene, only in blends with the bromostyrene copolymer, and others

  mixtures by adding slightly more decabromon oxide

  diphenyl, so that the percentage of bromine, based on the total weight of the mixture, is the same as in the mixtures containing the bromostyrene copolymer. The properties of the mixtures are reported in Table 3. Mixtures

  containing the bromostyrene copolymer have a temperature

  high load deflection structure and high Izod impact resistance. Most properties are approximately equivalent to those of prepared control mixtures

  with homopolymer of polystyrene, the arrow temperature

  under load being slightly higher, and the

  greatly improved fire. The mixture containing the bromostyrene copolymer received a fire resistance rating of V-1 without the addition of any flame retardant; it turned into V-O, with a very short burn time when only 3 parts of triphenyl phosphate were added.

TABLEAW 3

Comp. copolymer

bromo-

cyrene Parties

of homopo-

  atyrene lysate Phosphate Tri-decabromo phenyl diphenyl oxide Allo geme (z)

F 25 0 0 0 41

G 25 0 3 0 42

H 0 25 0 0 32

I 0 25 3 0 40

J 0 25 O. 8.1 37

K 0 25.0: 8.8 37

L 0 25 3 8.1 36

M 0 25 3 8.8 33

  n- Limit Resistance nt of elasticity to the city in tension traction (daN / mm2) (daN / mm2)

718 5,236

, 650 5,305

512 5,236

5,012 5,099

857 5,788

857 5,788

857 5,650

857 5,788

  Resistance Izod impact resistance (joules / cm) 7.15 9.39 6.09 9.61 3.15 2.83 2.56 3.31 (joules) 11.30 22.60, 42, 42 19 , 77 22.60 16.95 28.25 Brilliant Index of (4 5) viscosity (dl / g)

62.1 23.02

61.4. 22.68

59.1 24.60

59.7 24.60

59.2 26.40

37.7 28.40

58.2 27.80

58.0 28.90

Temperature

arrows

under load

Viscosity Class-

  UL94 (287'c) V-1 V-0 bad VI bad V-1 VI VI: each mixture also contains 75 parts of poly (2,6-oxydimethyl-1,4-phenylene), 3 parts of dioxide of titanium, 1 part of diphenyla and decyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide, 1.5 part of polyethylene, and 10 parts of Kraton G styrene butadiane hydrogenated block copolymer 1652 ,. ' rI "Co 4>, average burning time 9.2 2,2 27,1 16,5 14,8 11,0 8,6 6,9 o The same amount of bromine, added in the form of Decabromodiphenyl oxide resulted in an increase in color, a decrease in the sagging temperature under load and Izod impact resistance, and was much less effective in suppressing flames.

Example 8

  The mixtures described in Examples 5 to 7 were molded

  in the form of plates of 3.175 mm × 6.347 cm × 8.255 cm.

  The plates were placed on supports under a single thickness of conventional glazing glass on a rotating platform and illuminated at a distance of 7.62 cm with a battery of black light fluorescent lamps. The yellowness index was measured 24 hours apart by the method of ASTM D 1925, with the indicated results.

  in Table 4. The compositions containing the additive

  bromine broth of low molar mass yellowed rapidly (mixture JàM), while mixtures F and G containing the bromostyrene copolymer yellowed actually slightly less than the mixtures H :::: and I ::::, containing

  no bromine, in any form whatsoever.

TABLE 4

  Increase in yellowing index Composition :: 24 hours 48 hours 72 hours

F -0.5 1.2 2.8

G -0.5 1.7 2.8

H :::: 0.0 2.1 3.7

I :::: 0.1 2.1 3.6

-j: x :: 14.2 32.1 37.8

K :::: 15.0 28.6 39.2

L :::: 13.0 29.7 36.7

M :::: 13.7 29.4 37.7

  : Compositions of Table 3 Witness Example 9

  A mixture of 75 parts of poly (di-

  2,6-methyl-1,4-phenylene), 25 parts of the bromostyrene copolymer, 10 parts of styrene-butadiene-styrene hydrogenated block copolymers (KRATON G 1651), 3 parts of titanium dioxide, 3 parts of triphenyl phosphate 1 part of diphenyl and decyl phosphite, 0.15 part of zinc sulfide, 0.15 part of zinc oxide, and 1.5 part of polyethylene, as described in Example 1. We have

  reported below the properties of the composition.

  Elongation% 29 Tensile yield strength (daN / mm2) 7.441 Tensile strength (daN / mm2) 5.994 Impact resistance Izod (joules / cm) 0.96 Impact strength Gardner (joules) 27.12 Gloss (7 C) 38.9 Yellowness Index 24.3 Bend Temperature Under Load (C) 151 UL-94 VO Rating Average Burn Time (seconds) 3.1 Example 10 Molded compositions comprising 75 parts of poly (oxydimethyl) were prepared -2,6-1,4-phenylene), 24 parts of a

  polymer of bromostyrene or a bromostyrene copolymer

  styrene; 3 parts of titanium dioxide, 1.5 parts of triphenyl phosphate and 10 parts of a styrene-butadiene-styrene block copolymer (Kraton-G 1651), by extrusion and molding. The compositions had the properties

shown in Table 5.

TABLE 5

  % bromostyrene Resistance to Resistance Time-to-Polymer shocks Izod to shock combustion Appearance (joules / cm) Medium Gardner UL94 (joules) (s) 3.26 31.07 1.9 good 85 4.59 33.90- 1.7 good :: 4,27 1,69 0.9 laminate :: control

Example 11

  Molded compositions comprising 60 parts of poly (2,6-phenylmethylphenylphenyl) resin, 40 parts were prepared.

  of a bromostyrene polymer or a bromo-

  styrene-styrene; 1.5 parts of triphenyl phosphate and

  parts of a styrene-butadiene block copolymer

  styrene, by extrusion and molding. The compositions presented

  the properties shown in Table 6.

TABLE 6

  % Bromostyrene Resistance to Weather Resistance in the polymer shocks Izod shocks Gardner combustion Appearance (Joules / cm) (joules) UL 94 (s) 2.99 25.42 2.9 good 2.19 3.39 2 ,. 0 laminate :: 2.14 0.56 0.6 control laminate Comparative example

  1000 g of bromostyrene monomer (Makhteshim-

  27% ortho, 70% para, 3% meta) under a nitrogen atmosphere with 0.6 g of azobisisobutyronitrile and 0.6 g of dicumyl peroxide at 82 C. After six hours, put the product in

  in 1500 ml of water containing 6 g of polyvinyl alcohol

  and 4.5 g of gelatin and the polymerization was continued at 85-100 ° C. for 14 hours. Mixtures with poly (2,6-oxydimethyl-1,4-phenylene) were prepared by coprecipitation from toluene in methanol and the blends were blended.

  in films to determine the glass transition temperature.

  % Poly (2,6-Oximethyl) phenylene-1,4) Tg (1) (C) Tg (2) (C) -1

25,136,208

137 206

137 209

--- 211

  Mixtures have two transition temperatures

  vitreous, which is characteristic of a lack of compatibility

of these two materials.

Claims (10)

  A flame retardant thermoplastic molding composition, characterized in that it comprises: (a) a poly (oxyphenylene) resin; and (b) a styrene-bromostyrene copolymer. 2. Composition according to claim 1, characterized in that the poly (oxyphenylene) resin comprises units corresponding to the formula: Q "Q"   Q "Q in which Q is selected from the group consisting of   hydrogen, hydrocarbon radicals, hydrogen radicals,   halogenated carbon containing at least 2 carbon atoms between   the halogen atom and the phenyl ring, the oxyhydro-   carbon and halogenated oxyhydrocarbon radicals having at least two carbon atoms between the halogen atom and the phenyl ring, Q 'and Q "may represent the same radicals as Q, and in addition a halogen, provided that Q and Q both lack a tertiary carbon atom   and n represents an integer of at least 50.   3. Composition according to claim 2, characterized in   what the Q "groups represent hydrogen.   4. Composition according to claim 2, characterized in that the poly (oxyphenylene) resin is a resin of   poly (2,6-oxydimethyl-1,4-phenylene).   5. Composition according to any one of the claims   previous ones, characterized in that the weight ratio   styrene-bromostyrene ranges from 85:15 to 15:85.   6. Composition according to any one of the claims   characterized in that it comprises, by weight, from 20 to 90 parts of a poly (oxyphenylene) and from 80 to about - z2483444 parts of the copolymer.   7. Composition according to any one of the claims   previous characterized in that it further comprises a load.   8. Composition according to any one of the claims   characterized in that it still includes a flame retardant phosphate.   9. Composition according to any one of the claims   characterized in that it still includes a thermoplastic rubber.   10. Composition according to claim 9, characterized in that the thermoplastic rubber is a block copolymer ABA.