DE2119301C3 - Thermoplastic compounds with high impact strength - Google Patents

Description

30th

The invention relates to thermoplastic compositions with high impact strength made from mixtures of polyethylene ethers with a rubber modified polystyrene and or a polystyrene and a Rubber.

High molecular weight polyphenylene resins are technical high-performance thermoplastics with relatively high melt viscosities and emollients. which are above 275 C. They are suitable for There are a number of technical applications in which there is ■ Resistance at high temperatures is important. You can use slides. Fibers and molded parts processed will.

Certain properties of the polyphenylene ethers are undesirable for some technical applications. For example, molded parts made of polyphenylene ether are somewhat brittle due to poor impact strength. In addition, processing as a melt is difficult because of the relatively high melt viscosities and softening points because of the high temperatures required to soften the polymer and the problems associated therewith. /. As instability and discolouration, uninteresting The processing of a melt requires further specially designed process equipment for the input <, <, "atz at elevated temperatures.

US Pat. No. 3,383,435 describes a process for improving the processability of polythene-phenyl ether in the melt. To this end, the polyphenylene ethers are mixed with polystyrene resins, preferably chewing-modified impact polystyrenes . Mixtures of poly (2,6-dialkyl-1,4-phenylene) ethers with an impact-resistant polystyrene are technically important because they both improve the processability of the polyphenylene oxide as a melt and improve the impact strength of the moldings produced from the mixtures is achieved.

It is well known that the properties of high impact polystyrene resins largely depend on depend on the number, size and type of elastomeric particles dispersed in the resin. There is an optimal one Particle size in the range of 2 to 5 or 10 μ for chewable toughened polystyrene with a relatively narrow size distribution within this range (see, for example, Encyclopedia of Polymer Science and Technology. Vol. 13, 1970, p. 392. and GB-PS 1127 820 and 1174 214).

It has now surprisingly been found that mixtures based on a polyphenylene ether with a rubber-modified polystyrene or with a styrene resin and a rubber have considerably better impact strengths if the particle size of the dispersed elastomeric phase is kept below an average maximum of about 2 <i . The impact strength is significantly higher than that of comparable mixtures, in which the mean particle size is greater than about 2. B. about 6 · ι. is increased. ie lies within the range that was previously designated as the optimum. In addition, the appearance of the surface, in particular the gloss, and the resistance to aggressive solvents such as gasoline are surprisingly improved.

The invention relates to thermoplastic compositions with high impact strength from mixtures of a polyphenylene ether with a rubber-modified polystyrene and / or a polystyrene and a rubber, which are characterized in that they contain 0.1 to 30 percent by weight of a disperse elastomeric phase of natural or synthetic rubbers or those with grafted polystyrene contain, the particles of which have a mean diameter of a maximum of about 2 · ι .

Preferred·? Embodiment of the invention are those thermoplastic compositions in which the polystyrene resin on a rubber-free basis is 20 to XO percent by weight the total weight of the polystyrene resin on a rubber base and the polyphenylene ether matters.

The thermoplastic compositions generally consist of a mixture of two phases, a closed phase made of a polyphenylene oxide resin and styrene resin. in which a disperse phaw of particles of the elastomer is embedded. To various extents, depending on the production method of the masses, parts of polystyrene resins and polyphenylene ether resins can also be present in the disperse phase. ^1. "of the particles by known methods, for example by phase microscopy, which is particularly useful, or by microfiltration and by similar known methods

The polystyrene resin and the elastomer can be separated components with the polyphenylmather be put together. Apparently comparable with lower amounts of the elastomer Schltiu / iihigkcilcn ci / .iclt is preferred Combine a rubber-modified polystyrene resin with the polyphenylene ether *. The first method the particle size of the elastomeric phase is determined by mechanical mixing of the rubber, des Styrene resin and polyphenylene oxide resin set, z. H. reduced. In the second method, the particle size of the elastomer is e.g.

wisely by polymerizing styrene in the presence set of dissolved rubber under known conditions, being a disperse elastomer Phase, for example, of grafted crosslinked rubber particles in polystyrene, which is the closed Represents phase, is dispersed. The product is then combined with the Polyphenyleniither, whereby the size of the particle generally remains unchanged in the final mass.

The Polyphenyleniither. to which the invention is directed are well known and are exemplified in U.S. Patents 3,306,874, 3,306,875, 3,257,357 and 3,257,358.

A preferred group of polyphenylene ethers consists of recurring Syruclur units formula

y -

Q )

in which the ether oxygen alom of an L-inheil to the Bcnzolring of the next adjacent unit is bound, η a positive i-'an / e number of at least 50 and each Q radical is a monovalent substituent from the group consisting of hydrogen. Halogen, of tertiary n-carbon atoms free hydrocarbon residues, halogenated hydrocarbon residues with at least 2 carbon atoms between the halogen atom and the phenyl nucleus, hydrocarbonoxy radicals and halo-hydrocarbons »Is erstoffoxy radicals with at least 2 carbon atoms between the halogen atom and the phenyl nucleus. Numerous Examples of polyphenylene ethers falling under the above formula are in those mentioned above U.S. Patent Specified.

For the purposes of the invention, a group of polyphenylene ethers of the formula above preferred, in which each radical Q is an alkylresl with I to 4 carbon atoms.

These include, for example

Poly (2,6-dimethyl-1.4-phenylene) ether,
Poly (2,6-diethyl-1,4-phenylene ether,
Poly (2-methyl-6-ethyl-1,4-phenylene hither.
Poly (2-methyl-6-propyl-1,4-phenylcn) ether,
Poly (2,6-dipropyl-1,4-phenylene) ether and
Poly (2-ethyl-6-propyl-1,4-phenylene) ether.

Poly (2,6-dimethyl, 4-phenyl) ether is particularly preferred, that with polystyrenes over the entire range of proportions easily forms a compatible single-phase mass.

The term "polystyrene" used here means polystyrenes that are at least 25 percent by weight Contain polymorphisms that are of a vinyl aromatic monomers, e.g. B. a monomer of the formula

RC = CII ₂

in which R is a hydrogen atom, a lower alkyl radical for example with 1 to 4 carbon atoms or a halogen atom, Z a hydrogen atom, a vinyl radical. a Is halogen or a lower alkyl radical and />

represents U or an integer from 1 to 5. i »guided are. Suitable polystyrene resins are, for example, the homopolymers of styrene and polychlorostyrene and poly - «- methyl styrene. styrene-containing copolymers, z. B. Copolymers of ethyl vinylbenzene u- <d

ίο Diviny! benzene. Preferred of the polystyrene resins this class includes homopolystyrene and poly - \ - melhy! styrene. Styrene-i-methylstyrene copolymers, styrene-methyl methacrylate copolymers and poly - \ - chlorostyrene. Homopolystyrene is particularly preferred.

Dv.T includes the term "rubber" used here natural and synthetic polymeric materials which can be used at room temperature, e.g. B. at 20 to 25 C. Elastomers are. The term "rubber" thus includes natural or synthetic rubbers of the type generally used in the manufacture of impact polymers. All of these rubbers form a two phase system with the resin, e.g. B. a polystyrene resin, and set the disperse fine phase in the impact-resistant polyslyrol resin mass. Suitable rubbers door the purposes of the invention are, for example, natural rubber and polymeric diene rubbers. /. B. Polybutadiene and polyisoprene, and copolymers of these dienes with vinyl aromatic monomers such as Styrene. Suitable rubbers or rubber-like copolymers are, for example, natural crepe rubber, synthetic SBR rubber containing 40 to 98 percent by weight butadiene and 60 to 2 percent by weight Contains styrene and has been produced by emulsion polymerization by a hot or cold route is, and synthetic rubbers, for example made from butadiene, butadiene-styrene or isoprene for example be prepared by processes in which heterogeneous catalyst systemsc. z. B. aluminum trialkyl and a titanium halide. can be used, suitable for rv-rner as synthetic rubbers for the polymer mixtures according to the invention elastomeric modified diene homopolymers, e.g. B. polybutadienes and polychlorobutadienes with terminal hydroxyl and carboxyl groups. z. B. polychloroprenes. Polyisobutylene and copolymers of isobutylene with butadiene or isoprene. Polyisoprene. Copolymers of ethylene and Propylene and its interpolymer with butadiene. Thiokol rubbers. Polysulfide rubbers. Acrylic chewing stick. Polyurethane rubbers. Copolymers of dienes, e.g. B. butadiene and isoprene, with different Comonomers. z. B. unsaturated alkyl esters. z. B. Meth>! Methacrylate. unsaturated ketones, e.g. B. Methyl isopropyl ketone. Vinyl heterocycles. z. B.

Vinyl pyridine. Polyether rubbers and I pichlorohydrin rubbers. Preferred rubbers are polybutadiene and rubber-like copolymers of butadiene with styrene. These preferred rubbers large-scale production of rubber-modified impact polystyrene resins in the wide range of those mentioned above Publications mentioned particle sizes of the elastomers used '.

The phrase "rubber modified polystyrene resin." denotes a class of compounds that represent a two-phase system in which the rubber is dispersed in the form of discrete particles in a polystyrene resin matrix. The particles

can be formed by mechanically mixing the rubber and the polystyrene resin. In this In this case, particles of the rubber form the disperse dastomeric phase. On the other hand and this will The two-phase system preferably consists of interpolymers of an S'.yrene monomer and an Elastomers or rubber. These high-impact polystyrenes are becoming commonplace on an industrial scale produced by grafting onto rubber in the presence of polymerizing styrene. These systems consist of a closed phase of polymerized styrene monomer. in the rubber or the elastomer as a discontinuous elastomeric phase with or without grafted chains of polymerized styrene monomer is dispersed. the Particles can also contain entrapped polymerized styrene monomer. This has a certain Influence on their size.

Process for the production of kaulschukmodi-Izierten polystyrenes with controlled particle size well known. The GB-PS 1! 74214 describes <lu · polymerisation of rubber in mon ^ mciem stylol. This polymerization is carried out as a bulk polymerization, the mixture during the initial stages are agitated to form the desired particle size. Then the intensity of stirring is reduced and the polymerization »ends. In the case of the \ on Bender. .1. Appl. Polymer Sci .. 9. 2X87 (1965). becomes a block pre-registration of rubber in monomeric styrene ■ carried out stirring until the desired particle size has been echoed. whereupon water u.id Surfactants / ugeset / t are carried out and the polymerization in suspension / u end is carried out

In these brands, the elastomer is preferred Derived from butadiene, a buladiene-styrene copolymer, which is a mixture of these. These materials can be done according to known methods, ζ. Β the above Process are produced. They are also commercially available from a number of sources.

In US-PS 33 83 435 it is stated that polyfhenylene ethers and polystyrene resins can be combined with one another in all proportions and that the products have a single combination of dynamic properties. The mixtures according to the invention can therefore be 99 percent by weight Contains polyphenylene ether and 99 fcis l ⁿ n rubber-free polystyrene resin. In general, mixtures are preferred in which the polystyrene resin on a rubber-free basis makes up up to 80 percent by weight of the polystyrene and the polyphenylene ether because, after molding, they have the best combination of impact strength. Appearance ·! Of the surface and resistance to solvents. Mixtures in which the rubber-free polystyrene resin makes up 40 to 10 percent by weight of the total weight of poly-ityrene and polyphenylene ether are particularly advantageous and preferred are properties such as flexural strength and tensile strength. Hardness and, in particular, impact strength have their maximum in these preferred mixtures.

The rubber content, i.e. H. the weight component disperse clastomeric phase can vary, but no benefit is obtained if above a maximum about 30% of the total weight of the mass is exceeded. When the proportion of elastomer Phase falls below about 0.1 percent by weight, the impact strength deteriorates. The preferred one The proportion of the elastomeric phase is about 1 to 15 percent by weight, the higher proportion being used when the rubber is dispersed by mechanical mixing. If as preferred the rubber is in the form of an elastomeric styrene-rubber-graft copolymer, the lower amounts may be beneficial. In all cases, the preferred amount is the elastomeric Phase in the range between 1.5 and 6% of the total weight of the mass. Although it is at higher proportions the impact strength is clearly optimal, but other properties, e.g. B. Solvent Resistance and appearance of molded parts. As with the rubber particles grafted on Mixtures are obtained which have better impact strengths than those of mechanically mixed, d. H. non-grafted particles produced mixtures at the optimal proportion of ί.5 H- 6 percent by weight the mixtures p> -m; iP of the invention. which contain a finely divided elastomeric phase with grafted styrene, particularly preferred.

The method by which the Invention emäßen _r mixtures based on Polyphenylenäthcr. Polystyrene and rubber are not critically important provided that the process can do so. the maximum mean particle size of the elastomeric particles to 2 μ. preferably to 0.5 to 2 μ, or to keep them at these values. A process is preferred in which the polyphenylene ether is mixed with polystyrene and a rubber or with a rubber-modified polystyrene by any customary mixing method and the mixture formed in this way is processed, for example, by extrusion and hot forming.

Of course, other additives, e.g. B. Soft Macner. Pigmcnte. flame retardant agent. VerslärkerfüH-materials. z. B. glass thread or fibers and stabilizers are added.

In the context of the invention, other polymers, e.g. B. polyamides. Polyolefins are polystyrene. added to the mixtures. For example, it has been found that mixtures of polyphenylene oxide with equal proportions of polystyrene and rubber-modified polystyrene in one Particle size of the elastomer from 1 to 2 1 beat) Have toughness comparable to that of known compounds containing the same content of polyphenylene ethers, but in which all of the polystyrene resin is rubber-modified and ei.has the elastomer particle size of about 4; i.

ss These mixtures are not just more economical to manufacture ais. the well-known mixtures, rather have ticsser-looking surfaces even after injection molding.

The invention is further illustrated by the following examples, in which preferred embodiments unless otherwise stated, All mixtures are made by adding mixtures of the polyphenylene ether. aes styrene resin and rubber or impact-resistant polystyrene

fts rols and, if necessary, other components a single screw press with uneven pitch can be given, the extrusion temperature is maintained between about 232 and 288 ° C.

All parts are selected parts from the extrusion press Exiting strands are cooled according to the usual methods, chopped into granules, Stranggeprel.M. to granules! chop up! and to l'call sticks pressed.

example 1

22.7 kg of a mixture of the following compositions are produced

Poly (2.6-dimethyl-l.4-phenylcnl-

ether'l 4 ^ parts

K a ti I sch u k mod ι Ii / ie rl es

Polystyrene "'ι> 5 I hurry

Polyethylene ... 1.5 parts

I ridecslphosphite 0.5 I rush

Acrawa \. . . 0.25 I hurry

I il.indiowd 2 1 hurry

\ ιιim! .I, - m

1 ',. Iv-I- I, · I

•. · Ι, · ΐν '.., Μ! Ν ■ λ :. lll-i ....-, - ιΓ

, -Mi.- 'ι-η I'l · .-; mil, -ιιη: mi! [! ·> ■: ν.

The ι ie mi seh is shown in a 63. 5 -well -I 'index -S; ran pressc extruded relU. Oic preserved beaches are going to chilled, to (iranulally chopped and to l'rüfstähc praised The smallest part of the elastomer l'hase in the mixture remains I to J,

The following physical tiger sounds will be determined:

η η η

η ίο

Izod-Kcfhschl.igzähkcit

(iardnet -Schi.ig / ahi'jkcit
Elongation at break. . . .
Dimensional stability and the

Warm llX. 6 kg enr I
Tensile strength at ilcr

Stretch limit

Tensile strength at break
4? -Cdan / werl

(). "'> mkü 25.4 mm notch 2" * "cniku 4S' ^! ,.

123 (

i> hS k'j enr 5 ¹ M kl! enr Tm Comparison of T.rgebnisse Iaht cmc substantial improvement in the impact resistance determined during Ι / ήΙ-Icsi and Gardner test as well as the appearance of the surface! seen from the gloss value ι in the mixture containing the particles of 1 His 2 / in Compare with the mixture that contains luminosity of C> ■ / diameter.

He ι s ρ ιe I 2

22.7 kg of a self-extinguishing Itlammwidiigeni Mixture of the fo I loh de η together ^ etzum; will manufactured

I \ il \ i2.r> -dimeth'.l-

K4-phen> lcni., I! N ·! ι I ¹ IM M. ^ς Π I hurry kulchuk mocliiied

CoIy sty rol Is example! I.

Λ η im ■: kling ^ i. . . . ^ O I hurry

l'olyathy len. ... 1.5 I hurry

1 riphi'yl phosphate. ... '. Il I hurry

I ndecyl phosphite. . 1.0 I rush

Zmkstillid. . Ι. ^ς I hurry

M) " μ containing styrene

«Ultra mix 0.5 l'ile

After extrusion in a M.5-nim-Prode \ - Slangpiesse are the strands according to standard methods chilled, chopped up and down to test sticks. The miniere 'eilclu ngrohe in the elastomeric phase belr.i'jl I to 2 ■ ;. The foTjciuien physical i-i'jensehallen are determined:

Flexural strength PM6 kg enr

For purposes of comparison, the above-described 4 <\ 'request is repeated, but using a rubber-modified polystyrene roll of high toughness. that is a disperse elastomeric phase with an average particle size of about 6 , | Range 2 to II contains and has a polybutadiene content of about this weight percent instead of the rubber-modified polystyrene of Example I. After mixing, the composition contains an elastomeric phase with a particle size of about 6 μm. The following physical properties are determined:

Notched Izod Impact Strength ... 0.25 mkg

25.4 mm notch Gardner high impact wedge .... 230 cmkg

Elongation at break 5! "Η bo

Dimensional stability in the

Heat ( 18.6 kg cm ² 1 131 C "

Tensile strength at the

Yield strength 6X2 kg cm ²

Tensile strength at break ... 577 kg enr

45 - gloss value 59

Flexural modulus 26,717 kg cnr

Tuck resistance 2 142 kg cm ²

l / od-kerhschla-jzaiiigkeit.

C ianlner impact rate
Elongation at break
1-form persistence in iler

Wiiniie I IN.fi kg enr I.
Ziinfesiigkeii at the

Stretch limit
Tensile strength at break.

Bending module

Flexural strength

0.71 mkg 15.4 mm Kerhe 202 ctnki! 49 ".,

122 C

640 kg cm

5 ⁷ "kL 'enr

24 031) kü enr "

I S29 ki; enr

For the purpose of this we have repeated the request, but using impact / similar polystyrene, which is a disperse elastomeric phase with a mean linear diameter of 6-j. Contains range 2 to 10 / l, instead of the rubber-modified polystyrene of the example !. The final mixture will have a particle size in the same range. The following physical properties are determined:

Notched Izod Impact Strength.

Gardner impact strength .

Elongation at break

F ormbes'.ändtgkeit in the

Warm (18.6 kg enr I..
Tensile strength at the

Stretch limit

Tensile strength at break.

Bending module

Flexibility

0.25 mkg 25.4 mm notch 138cmk « 40 "o

121 C

657 ka cm ²

584 ki cm ²

23 852 k »cm ²

2 170 ka cm ²

A comparison of the results shows an essential Improvement of the notched impact strength of the compounds containing a dispersed elastomer in Form \ on particles with a maximum diameter of 2 · ι contain.

H ο ι s ρ ι C I J

22.7 ki! finer self-extinguishing if flame retardant Mixtures of the following composition are made:

Polyphenylene ether. ... ... 4 (1 'leile

High impact polystyrene (as in Example 11. W) parts

Polyethylene 1.5 leile

I rideeylphosplm 0.5 parts

[riphcnytphxsphiil 9 leile

Polytelraflun racks. . . π I foil

After extrusion in a 3.5 mm rod (the extrusion presses are cooled, chopped and pressed) the mean particle size in the elastomeric phase ranges from 1 to 2 times The following standard properties are determined:

l / od-Kerhsehlag / ähigkeit. . . . 0. " ⁷ I mkg

25.4 mm notch

(iardncr-blow / ühiiikcit - ^ ficmkg

Elongation at break ^ ϊ "»

Dimensional stability in the

Heat | 1Χ.6 kg cm ^:) 104 (

Tensile strength at tier

Stretching cycle / c 562 kg cm ²

Tensile strength at break .. 522 kg cm '

45 -Oilance value ftl.s'

For purposes of comparison, the above-mentioned experiment is repeated, but using a polystyrene of high impact / erium kit with a ruined particle size of 6 %. (Area% to 10 μ) in place of the kautschukmodifi / ierten poly llyrols of Example I. The final mixture has tine particle size in this area. The following physical properties are determined:

Notched Izod impact / strength .... 0.25 mkg

25.4 mm notch

Gardner impact strength .... 58 cmkg

Elongation at break 42%

Dimensional stability in the

Warm (18.6 kg cm ² ) 99 C

Tensile strength at the

Yield strength 605 kg cm ²

Tensile strength at break .... 506 kg cm ²

A comparison of the results shows a significant improvement in the notched impact strength in mixed undertakings . which hold a dispersed elastomer in the form of lights with a maximum diameter of 2 μm.

Example 4

22.7 kg of a mixture of the following composition are made:

Polyphenylene ether (PPO) 30 parts

Impact-resistant polystyrene as in

Example 1 70 parts

Polyethylene 1.5 parts

Tridecyl phosphite 0.5 parts

Triphenyl phosphate 6 parts

After extrusion in a 63.5 mm Prodex extruder, the strands are cooled by conventional methods, chopped into granules and pressed into test bars. This mixture, which contains about 68

Wiehispio / ent Styrolhar / (rubber-free Hasist, based on bonded Styrolhar / (Kaulschukfree) and l'olyphenyleniither. and contains about 5.X "» dispersed elastomeric l'hase with a particle size of 1 to 2 · ι , has a higher Ker'ischlag / ähigkeii H) JiX compared to 0.235 mkg 25.4-mm ■ Chervil as similar known mixtures, which are made of rubber-modified polystyrene with a particle size of 2 to 1 inch (IS patent 3.1 S3 435) ΓοΙι'λmien physical characteristics are determined:

1 / od-notch / equality. . . . O.fiX mkg 25.4 mm notch Dimensional stability in 'ler Heat I IX.f 'kg em I ... K) S C Elongation at break 44 ",, Tensile strength at the Stretchers / e 527 ki! enr '

Example 5
22.7 ku a mixture of the following combinations

set / ung are produced:

25 file

75 parts
1.5 parts
0.5 part «,
ft parts

Polyphenylene ether (ITOl ...
Impact-resistant polystyrene as in

Example I.

Polyethylene

Tridecyl phosphite

Triphenyl phosphate

After extrusion in a di: mm Prodex extruder, the strands are cooled. / 11 Granules chopped up and pressed into test sticks. The dispersed particles of the elastomeric phase have an average diameter between 1 and 2 μ. The following physical properties are determined:

Notched Izod impact strength

0.55 mkg
25.4 mm notch
34 "η

Elongation at break

Dimensional stability in the

Heat (18.6 kg cm ² ) 106 C

Tensile strength at the

Yield strength 527 kg enr

Tensile strength at break .... 506 kg cm '

A similar known mixture, but which is an impact-resistant polystyrene with a particle size of 2 up to 10 μ (US-PS 33X3 435. Example 7 and 1 Fig. 18). had an impact strength of only about 0.235 mkg 25.4 mm Kcrbc.

Test bars produced from the products of Examples' and 2, which were immersed in gasoline at 1% deformation, showed no catastrophic damage after 15 minutes if the average particle size was 1 to 2 μ (impact-resistant polystyrene as in Example 1 ).

In contrast, all of the test specimens failed (complete destruction), which were prepared mixtures of the Mi, in which the particles were larger (μ average particle size 6, the range from 2 to 10 μ), in less than 15 seconds at 1% deformation in gasoline.

Example 6

A mixture is prepared which contains 50 parts of poly (2,6-dimethy! -L, 4-phenylene) ether. Contains 45 parts of crystalline polystyrene and 5 parts of polybutadiene rubber. First of all, the rubber and the

It

Stable polystyrene has been intensively mixed in a Banbtiry mixer, until it has a mean diameter of 1 to 2 mm. The mixture is then extruded together with the polyphenylene ether, with a smooth joint. mixed mass, in which the elaslomercn I have a grotto from I to 2 μ , obtained w '/ d. This compound results in molded parts with a high grain / strength and improved gloss, if they are cooled, processed into granules / hacked unil by extrusion or injection molding vs. irtl.

H e ι s ρ ι e I 7

The experiment described in Example I is repeated, but using a polystyrene instead of the polystyrene modified with polybutadiene. tla < ¹ ) percent by weight of an elastomeric phase which consists of a rubber-like Slvrol-Buliidien copolymer. which contains 77 percent by weight buladiene units and 23 percent by weight styrene units has been formed. The final mixture has a particle size between 0.5 and 2 μ. The score is high and comparable to that of the Example I product.

Example p

Three mixtures are made from the following ingredients:

mixture Λ Il

P Li Ic

Poly (2,6-dimethyl-1,4-phenylene) - 40 40 40 iilher IPPOl
Modified rubber
Polystyrene

Particle size

3 to S μ 65

3 to IO μ 65

I to 2 υ 65

Notched Izod impact strength,
mkg / 25.4 mro notch
Tensile strength at the
Yield strength, kg cm ²
Tensile strength at break,
kg cm ²
Strain. %

mixture B. C. A. 0.25 0.53 0.235 633 640 675 534 520 548 46 47 36

The values / own, because the mixture C "one far has a higher notch impact than the mixtures Λ and B. They indicate that these properties are present can be reached with the same goblet sound if hlastomer parts are in a range from 1 to 2 ·. · an Digit of a range from 3 to IO μ. as is the case with commercially available rubber-modified polystyrenes is customary and has hitherto been used in known mixtures based on polyphenylene ethers will.

Example ')

ΛιιΓ graze the manner described in Example I. Mixtures made, with | cdoch half of the The rubber-modified polystyrene of Example I is replaced by crystalline polystyrene. The mixtures have the following composition:

.15

45

All of the above polystyrenes contained 7.5 percent by weight rubber.

The three blends were made in a 19.05 mm extruder (Waync) extruded and pressed in a 25g press (Ncwbury). The individual mixes contain a dispersed elastomeric gel with small particle diameter corresponding to the of the rubber-modified styrene resin. The following properties are determined:

60

Misl Ιπιιιμ ι ι I) I L-IL- 45 45 Poly (2,6-dimethyl 45 l.4-phenylene) ether (PPO) 27.5 Kuutschuk modifications 55 Polystyrene of Example I. Particle size I to 2 μ SS From US-PS 33 83 435. Example 7. Particle size 2 to IO μ 27.5 Crystalline polystyrene 1.5 1.5 Polyethylene 1.5 0.5 0.5 Tridecylphosphil 0.5 0.25 0.25 Aera wax 0.25 1 t Titanium dioxide 2

liclLll UCIIl Oll <lll ^: piC >> CII CIIIIlClItCII UIC IV |! M,! UUIt: C! l

dispersed elastomer particles with the same diameter as in the starting materials. the end Test specimens produced from the mixtures have the following properties:

mixture
I) Η

Notched Izod Impact Strength, mkg / 25.4mm notch
Melt viscosity (poise)
Strain, %

Dimensional stability in
of warmth, C

0.79

0.25 0.235

2540 2600 2350 48 51 59 123 131 138

The results show that by mixing the high impact polystyrene having a particle size of 1 to 2 μ with a substantial proportion of rubber-free styrene resin (mixture F) the costs are high be lowered, however, the strength properties the mixture B. which had twice the rubber content of the mixture F maintained

been. ϊ- Isi remarkable, dall the mixture! a higher l'ormhestiindigkeit in the worm than the Vischung K.

Hey spie I IO _ς

The following polyphenylene ethers are used in place of poly (2.fi-diniethyl-1.4-phenylene) ether in the mixture described with Example I

Poly (2. (i-diethyl-1.4-phenylene) ether. Poly (2-methyl-6-iithyl-1.4-phenylene): illii-r. Pol \ (2-methyl-f> -prop \ l- l.4-phcnylcn); iilKT. Pol \ (2 / i-di props I- l.4-phenvlen) ether. Poly (2-ethyl-6-propyl-1.4-plienylene) ether.

The final mixes have iilinliclu ii; jcm- ι; »» .Holding u ¹ ■ the geniiiU example I manufactured Mi- «.Ίιιιημ.

H e ι s ρ ι e I Il

The folue.ulen polystyrene resins are replaced in place of. (. des kri'i! linen lloniopolysiyrols in mixtures iler /tisamntcn-.cl/unt: \ cf.M-ndei:

l'oK-ii-methylslyrol.
Styrene-fi-methylstyrene copolymers. Styrene-methyl methacrylate copohmeies. Polv - '(- chlorostyrene.
Styrene-acrylonitrile-n-mi'ihyls'yii'l terpolymersv

The mixtures obtained have similar properties like the Miscluii ■; ■ described in example 6

The following rubbers are used instead of the polybulids in mixtures of those mentioned in the example (S / iisainmensel / ung used:

(Ίepe natural rubber.

Styrene-Huiadien-C'opolymeres i2. \ 5 "n Si wnli. M el hy Ii so propen y I keton-Hu I, ι dien

(Ό polymeres 150 "ο Metliylisopropcnylkctoni. Λ1 Ii \ len-propylene hat adieu- Tel pol \ nicies.

The mixtures obtained have similar characteristics as described in Example 6 mixture

Claims (2)

Patent claims: 1. Thermoplastic compositions with high impact strength s made from mixtures of a polyphenylene ether with a rubber-modified polystyrene and / or a polystyrene and a rubber, characterized in that that they contain 0.1 to 30 percent by weight of a disperse elastomeric phase of natural or synthetic Rubbers or those with grafted polystyrene contain their particles have a mean diameter of a maximum of about 2 u. 2. Thermoplastic composition according to claim 1, characterized in that the polystyrene resin on a rubber-free basis, 20 to 80 percent by weight of the total weight of the polystyrene resin rubber-free base and polyphenylene ether.