DE19805587A1 - Transparent thermoplastic molding compounds based on styrene / diphenylethylene copolymers - Google Patents

Abstract

The invention relates to thermoplastic moulding materials containing A) between 5 and 95 weight % of a copolymer of styrene and 1,1-diphenylethene with a diphenylethene content of between 1 and 15 weight %, B) between 5 and 95 weight % of crystal-clear or impact-resistant polystyrene or polyphenylether and C) between 0 and 90 weight % other additives, where the sum of A), B) and C) is 100 weight %.

Description

The invention relates to thermoplastic molding compositions containing

• A) 5 to 95 wt .-% of a copolymer of styrene and 1,1-diphenyl ethene containing diphenylethene in the range of 1 to 15% by weight,
• B) 5 to 95% by weight of crystal-clear or impact-resistant polystyrene or Polyphenylene ether and
• C) 0 to 90% by weight of further additives

the sum of A), B) and C) being 100% by weight.

Furthermore, the invention relates to the use of thermoplastic molding compounds for the production of fibers, films and moldings as well as fibers, films and moldings therefrom.

Thermoplastic molding compounds based on styrene / 1,1-diphenyl Ethene copolymers are known for example from WO 95/34586. They have high glass transition temperatures. As a rule, that is Compatibility of these copolymers with other polymer compo nenten low, so that the molding compositions are not transparent.

The object of the present invention was therefore thermoplastic Molding compositions based on styrene / 1,1'-diphenylethene copolymers To make available the above disadvantages exhibit, especially good heat resistance, high stiffness ability and transparency or translucent.

Accordingly, the thermoplastic described above Molding compounds found.

As component A), the thermoplastic molding compositions contain 5 to 95% by weight, preferably 25 to 90% by weight, of a copolymer of a vinylaromatic monomer and 1,1-diphenylethene or of those on the aromatic rings, optionally with alkyl groups of up to 22 C-substituted derivatives. A static copolymer of styrene and 1,1-diphenylethene is preferably used. The content of 1,1-diphenylethene in the copolymer is expediently from 1 to 15% by weight, preferably from 5 to 15% by weight, or the corresponding molar amount of a derivative derived from 1,1-diphenylethene. The weight average molecular weight M _w of component A is 10,000 to 2,000,000 g / mol, preferably 20,000 to 1,000,000 and very particularly preferably 50,000 to 500,000 g / mol.

The copolymers that can be used as component A) are per se known. Their manufacture is described in detail in WO 95/34586 wrote.

The molding compositions according to the invention contain as component B) 5 to 95 wt .-%, preferably 10 to 75 wt .-% crystal clear or impact-resistant polystyrene or polyphenylene ether. The production of crystal clear or impact-resistant polystyrene is known and for example in A. Echte, Handbuch der Technische Polymer chemie, Verlag VCH Weinheim, 1993, chapter 8.3 page 475 ff be wrote. Mixtures with radika are particularly preferred Made from standard polystyrene and with impact modifi cation decorated polystyrene. Can be modified as impact modified polystyrene all rubber-modified, in particular by polybutadiene or Styrene-butadiene block copolymers modified polystyrenes be used. Suitable as clear polystyrene for example standard polystyrene 158 K or 168 N BASF Aktiengesellschaft. The impact-resistant polystyrene is preferred wise translucent, like polystyrene 585 K from BASF shares society. To get a transparent molding compound, it is expedient to use transparent standard polystyrene or polyphenylene ether.

Can modify the properties and processability the thermoplastic molding compositions as component C) 0 to 90 wt .-%, preferably 0 to 65 wt .-% further additive substances included. Examples of these are impact modifiers Polymers, fibrous or particulate fillers, halogen-containing or halogen-free flame retardants, or processing aids substances that are added in usual quantities. Become multiple also antioxidants or UV stabilizers added to a particular to achieve greater durability under the influence of the weather.

The impact modifi used to improve toughness decorative polymers (also impact modifiers, elastomers or Rubbers called) are preferred in amounts of 0 to 30 3 to 20 and in particular 5 to 15 wt .-% used.

As rubbers which increase the toughness of the copolymers A), z. B. called the following:
Polyoctenylenes, graft rubbers with a cross-linked, elastomeric core, which is derived, for example, from butadiene, isoprene or alkyl acrylates and a graft shell made from polystyrene, further copolymers from ethylene and acrylates or methacrylates, and the so-called ethylene-propylene (EP) and ethylene - Propylene diene (EPDM) rubbers, furthermore the EP or EPDM rubbers grafted with styrene.

Furthermore, block copolymers with up to six, preferably with up to four identical or different blocks, both linear as well as star-shaped (so-called radial block copolymers) can be connected, are used. Block are preferred copolymers containing at least one block of vinyl aromatic Monomers, which are preferably at the end of the polymer chain finds own.

Mixtures of block copolymers of different structures, e.g. B. Mixtures of two and three block copolymers or of whole or partially hydrogenated and unhydrogenated block copolymers can also be used.

Such impact modifying polymers are known per se and described in the literature. Just for example here US-A 4 085 163, US-A 4 041 103, US-A 3 149 182, US-A 3 231 635 and US-A 3,462,162.

Corresponding products are also commercially available, e.g. B. a Polyoctylene of the designation Vestenamer® (Hüls AG), metallocene catalytic polyethylenes like Affinity® (DOW) or Luflexen® (BASF) and a large number of suitable block copolymers with at least one egg vinyl aromatic and an elastomeric block. Exemplary be the Cariflex®-TR types (Shell), the Kraton®-G types (Shell), the Finapren-® types (Fina), the Europrene®-SOL-TR types (Enichem) and Styroflex® and Styrolux® (BASF).

The molding compositions according to the invention can be used as further additives 0 to 50, preferably 5 to 40 and in particular 10 to 35% by weight a fibrous or particulate filler or their Mi included.

Preferred fibrous reinforcing materials are carbon fibers, Potassium titanate whiskers, aramid fibers and particularly preferably glass fibers. When using glass fibers, they can improve ren compatibility with the thermoplastic polyamide (A) with a sizing agent and an adhesion promoter.  

In general, the glass fibers used have a diameter in the range from 6 to 20 µm.

The incorporation of these glass fibers can take the form of both glass fibers and in the form of endless strands (rovings) The average length of the glass is in the finished injection molded part fibers preferably in the range of 0.08 to 0.5 mm.

Suitable particulate fillers are amorphous silica, Asbestos, magnesium carbonate (chalk), powdered quartz, mica, Talc, feldspar and especially calcium silicates such as wollastonite and kaolin (especially calcined kaolin).

The molding compositions according to the invention can also provide flame protection medium in a concentration of 0 to 20 wt .-%, preferred from 1 to 15% by weight, in particular 3 to 10% by weight, based on the total weight of the molding compound.

Suitable flame retardants are e.g. B. polyhalodiphenyl, poly halodiphenyl ether, polyhalophthalic acid and their derivatives, Polyhalogenated oligo- and polycarbonates, the corresponding Bromine compounds are particularly effective.

Examples of these are polymers of 2,6,2 ', 6'-tetrabromobisphenol A, tetrabromophthalic acid, 2,6-dibromophenol and 2,4,6-tri bromphenols and their derivatives.

The preferred flame retardant is elemental phosphorus. In the As a rule, the elementary phosphorus with z. B. polyurethanes or Aminoplasts can be phlegmatized or coated. Also are Concentrates of red phosphorus e.g. B. in a polyamide, elasto suitable or polyolefin.

Combinations of elemental phosphorus are particularly preferred with 1,2,3,4,7,8,9,10,13,13,14,14-dodecachloro-1,4,4a, 5,6,6a, 7, 10,10a, 11,12,12a-dodecahydro-1,4: 7,10-dimethanodibenzo (a, e) -cy clooctan (Dechlorane®Plus, Occidental Chemical Corp.) and optionally a synergist z. B. antimony trioxide.

Phosphorus compounds such as organic phosphates, phosphonates, Phosphinates, phosphine oxides, phosphines or phosphites are just if preferred. Triphenylphosphine oxide and Called triphenyl phosphate. This can be used alone or mixed with Hexabromobenzene or a chlorinated biphenyl and, optionally, Antimony oxide can be used.  

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

where Q represents the same or different residues of hydrocarbon residues such as alkyl, cycloalkyl, aryl, alkyl substituted aryl and aryl-substituted alkyl, halogen, hydrogen and their combinations, provided that at least one of the for Q is an aryl radical.

Examples of such suitable phosphates are e.g. B. the following:
Phenyl bisdodecyl phosphate, phenyl bis neopentyl phosphate, phenyl ethylene hydrogen phosphate, phenyl bis (3-5,5'-trimethylhexyl phosphate), ethyl diphenyl phosphate, 2-ethyl hexyl di (p-tolyl) phosphate, bis (2-ethyl hexyl) phenyl phosphate, tri (non , Phenylmethyl hydrogen phosphate, di (dodecyl) p-tolyl phosphate, tri cresyl phosphate, triphenyl phosphate, dibutylphenyl phosphate and diphenyl hydrogen phosphate. The preferred phosphates are those where each Q is aryl. The most preferred phosphate is triphenyl phosphate. The combination of triphenyl phosphate with hexabromobenzene and antimony trioxide is also preferred.

Such compounds are also suitable as flame retardants, which contain phosphorus-nitrogen bonds, such as phosphoronitrile chloride, phosphoric acid ester amides, phosphoric acid ester amines, Phos phosphoric acid amides, phosphonic acid amides, phosphinic acid amides, Tris (Azi ridinyl) phosphine oxide or tetrakis (hydroxymethyl) phosphonium chloride. Most of these flame retardant additives are available in the stores.

Other halogen-containing flame retardants are tetrabromobenzene, Hexachlorobenzene and Hexabrombenzene as well as halogenated polystyrenes and polyphenylene ether.

The halogenated described in DE-A-19 46 924 Phthalimides can be used. Of these, in particular N, N'-ethylene bistetrabromophthalimide gained importance.  

Other additives include stabilizers and Oxidation inhibitors, heat decomposition agents and cerium settlement by ultraviolet light, lubricants and mold release agents, Dyes, pigments and plasticizers.

Oxidation retarders and heat stabilizers, which the thermo plastic masses can be added according to the invention, are z. B. Group I metal halides of the periods systems, e.g. B. sodium, potassium, lithium halides, optionally in Connection with copper (I) halides, e.g. B. chlorides, bromides or iodides. Furthermore, zinc fluoride and zinc chloride can be used be applied. Also sterically hindered phenols are hydro quinones, substituted representatives of this group and mixtures of these compounds, preferably in concentrations up to 1% by weight, based on the weight of the mixture, can be used.

Examples of UV stabilizers are various substituted ones Resorcins, salicylates, benzotriazoles and benzophenones, which in the generally used in amounts up to 2 wt .-%.

Materials to increase electromagnetic shielding Waves like metal flakes, powders, fibers, metal coated Fillers can also be used.

Lubricants and mold release agents, usually in quantities up to 1% by weight of the thermoplastic composition are added Stearic acid, stearyl alcohol, stearic acid alkyl esters and amides as well as esters of pentaerythritol with long-chain fatty acids.

Among the additives are also stabilizers, the Zer settlement of the red phosphorus in the presence of moisture and Prevent atmospheric oxygen. Compounds of the Cadmiums, zinc, aluminum, silver, iron, copper, antimony, Tin, magnesium, manganese, vanadium, boron, aluminum and Titans called. Particularly suitable connections are e.g. B. Oxides the metals mentioned, also carbonates or oxicarbonates, Hydroxides and salts of organic or inorganic acids such as Acetates or phosphates or hydrogen phosphates and sulfates.

The thermoplastic molding compositions according to the invention can known processes can be prepared by the Starting components A), B) and, if appropriate, further additive substances C) in conventional mixing devices such as screw extruders preferably twin-screw extruders, Brabender mills or Ban bury mills mix and then extruded. After the extru The extrudate is cooled and crushed.  

In order to obtain a molding compound that is as homogeneous as possible, one is inten active mixing advantageous. These are generally medium Mixing times from 0.2 to 30 minutes at temperatures of 160 to 320 ° C required. The mixing order of the components can be varied, two or possibly three components can be premixed, but all components can be common sam mixed.

Masses according to the invention can also be obtained by pultrusion be prepared as described in EP-A-56 703 is. The glass fiber strand with the polymer mass is through soaks and then cooled and crushed. The glass fiber length in this case is identical to the length of the granules and is between 3 and 20 mm.

The thermoplastic molding compositions according to the invention stand out characterized by high rigidity and heat resistance. they are translucent or transparent.

They are suitable for the production of foils, fibers and shapes bodies, in particular for the production of transparent films and molded parts z. B.) in food, automotive, electrical, Electronics, construction, construction and leisure, for those in the following exemplary applications are listed:

a) Food sector

Drinking cups for hot or cold drinks, disposable tableware such as Tas sen, plates, cutlery; Bowls for salads, microwave dishes for single use or for reusable use. Jam Be holder. Containers for dairy products such as yogurt, quark, cream, Cream, cheese. Blister packs for technical parts such as nails, Tool, for toys; Tablet blister packs, blisters for toothbrushes, bottles, packaging foils, household foils, Roasting foils;

b) Automotive, electrical and electronics sectors

For vehicle interior parts, air duct installation parts, loudspeaker housings, audio and video cassette housings, warm air nozzles, keyboard covers, cable ducts, busbars, electrical distribution boxes, power strips, coil formers, plates, wheel covers, vehicle steering wheel covers, heating fan controls, control cabinets, vehicle Exterior mirror body, air intake grille, motor vehicle shelves in the interior, housing of electrical devices such as measuring devices (volt-amperes, ohmmeters), kitchen appliances such as food processor, stirrer, mixer, mixing stick, toaster, egg cooker, coffee machine, coffee grinder, fan heater, air conditioners, electr Cutting machine, electric knife, vacuum cleaner, ventilators. Cover of stove, microwave oven, dishwasher, washing machine, dryer. Housings of audio, video systems, televisions, irons, computers, copiers, faxes, telephones, teleprinters, cameras, printers, plotters, typewriters, control units, timers, chargers, batteries, capacitors, pumps. Electrical functional parts such. B. switches, Elektroinstalla tion housing for transformers, deflection coil body for TV devices;
Decorative strips for motor vehicles, spiral cables, ball joint seals, bushings, plain bearings, stabilizers, torsion bars, gear knobs, impact zones for motor vehicles, bumpers, spoilers, sills, wheel trims. Guide, rain strips. Components in the engine block and in the engine lubrication, e.g. B. camshaft sprockets, chain guide rails, toothed belt covers, intake pipes, engine covers, oil pan, oil filter housing, clutch pressure bearing. Components in the fuel supply system, e.g. B. Fuel filter housing. Components in gearboxes, gears; Tachometer drive. Chassis components Chip carriers, isolators, connectors, parts of infusion sets, sterilizable medical or diagnostic parts such as beakers, dishes, scales, housings for dialyzers, forceps, surgeons. In instruments; Valves, battery cases, grills, rear panels, parts for antennas, CD packaging, compact discs;

c) Construction, construction and leisure areas

Window profiles, pipes, tubes, cable sheathing, double-wall sheets, hoses, parts of skis, snowboards, snow chains, rollers, bellows, profiles, sieves and sieve elements, ski boots and parts for ski boots, toys, housings for drills, electric planers, grinders, saws , Gluing devices, cordless screwdrivers. Seals, rollers, shells for casual shoes, housings for binoculars, video cameras, cladding, garden furniture, surf boards, lawn mower housings, letter boxes, sanitary ware, refrigerated furniture, furniture;
Glazing, skylights, coextruded protective layers on e.g. B. ABS, PVC, PC. Light guide;
Sacks, shrink films, films for agriculture, construction films, films for carrier bags, automatic and laminating films, diaper films, bottles and tubes for cosmetics, pharmaceuticals and chemicals. Pipe coatings, rail washers, sealing rings, protective caps, sleeves, clips, slip closures;

e) Other areas of application

Credit cards, credit cards, adhesive rolls, furniture foils, water filter housing, traffic signs, disposable syringes, tablet tube Chen, fibers, spunbonded nonwovens, foams, insulation elements, view sleeves, pen case.

Examples

The following components were used:

Component A2) (S / DPE copolymer with 15% by weight DPE)

A styrene / 1,1-diphenylethene copolymer with 15% by weight 1,1-diphenylethene and a weight average molecular weight M _w of 245,000 g / mol was produced according to the examples in WO 95/34586:
A 10-liter metal kettle with a double jacket for cooling and heating and stirrer was inertized for several hours with a refluxing solution of DPE / sec-butyllithium in cyclohexane.

After the cleaning solution had been drained, 3760 ml of cyclohexane and 586 ml (600 g; 3.33 mol) of 1,1-diphenylethene were introduced and titrated with sec-butyllithium until they turned red. Now 72.4 ml of a 0.27 M sec-butyllithium solution in cyclohexane were added and the reactor contents were thermostatted to 70.degree. Then 3748 ml (3400 g; 32.7 mol) of styrene were added in 200 ml steps every 10 min. After a reaction time of 180 min, titration was carried out with ethanol until colorless, the polymer was precipitated by dropping the polymer solution into ethanol and the white powder which had been filtered off and washed several times with ethanol was dried in vacuo (1 mbar) at 200 ° C. for 2 h.
Yield: 3948 g (98.7%); Styrene content (FTIR): 85.1% (85% theor.); DPE content (FTIR): 14.9% (15% theor.); Tg (DSC): 121.5 ° C (width of the glass step: 9 ° C); Molar masses (GPC, polystyrene calibration, g / mol): M _n 177 000, M _w 245 000.

The components A1), A3), A4) and A5) were produced analogously to components A2):
Component A1) (S / DPE copolymer with 12% by weight DPE)
Component A3) (S / DPE copolymer with 18% by weight DPE)
Component A4) (S / DPE copolymer with 30% by weight DPE)
Component A5) (S / DPE copolymer with 45% by weight DPE)

Component B1)

Standard polystyrene with a viscosity number VZ of 96 ml / g (0.5% in toluene, 23 ° C), a molecular weight M _w of 250,000 g / mol and a non-uniformity M _w / M _n of 3.5.

Component B2)

Translucent, impact-resistant polystyrene with a viscosity number VZ of 76 ml / g (0.5% in toluene, 23 ° C) and a melting volume rate MVR (200 ° C / 5 kg) of 4.3 ml / 10 min. Capsule particle morphology with 0.4 µm diameter), polybutadiene content 10%.

Component B3)

Poly (2,6-dimethyl-1,4-phenylene ether) with a reduced viscosity η _red of 0.65 (1% in chloroform, 25 ° C).

Production of molding compounds

Components A), B) and C) were given in Table 1 proportions by weight in a twin-screw extruder (ZSK 30 der From Werner & Pfleiderer) at a temperature of 250 ° C melted, homogenized and as a strand in a water bath extruded. The dried granules then became the norm test specimens sprayed.

Measurement methods

The glass transition temperature (Tg) was determined using differential Scanning calorimetry (DSC) determined according to DIN 53 765.

The melt volume rate MVR (200 ° C / 5 kg) was according to ISO 1133 200 ° C / 10 kg determined.

The notched impact strength ak (Charpy) was derived from the impact bending experiment determined according to DIN 53 453.

The transparency was assessed visually and rated as follows:
+ transparent
0 translucent
- opaque

Table 1

Composition and properties of the molding compounds

The comparative tests show that the molding compositions from S / DPE- Copolymers with 18 wt .-% DPE and crystal clear or impact-resistant Po lystyrene (V1, V2) or 45 wt .-% DPE and polyphenylene ether their Lose transparency or translucent and become opaque. Soon two occur early in the DSC (Differential Scanning Calorimetry) separated glass steps.

Claims (5)

1. Thermoplastic molding compositions containing

• A) 5 to 95% by weight of a copolymer of styrene and 1,1-diphenylethene with a diphenylethene content in the range of 1 to 15% by weight,
• B) 5 to 95 wt .-% crystal-clear or impact-resistant polystyrene or polyphenylene ether and
• C) 0 to 90% by weight of further additives

the sum of A), B) and C) being 100% by weight. 2. Thermoplastic molding compositions according to claim 1, containing

• A) 25 to 90% by weight of a copolymer of styrene and 1,1-diphenylethene with a diphenylethene content in the range of 1 to 15% by weight,
• B) 10 to 75% by weight of crystal-clear or impact-resistant polystyrene or polyphenylene ether and
• C) 0 to 65 wt .-% additives

the sum of A), B) and C) being 100% by weight. 3. Use of the thermoplastic molding compositions according to the claims Chen 1 or 2 for the production of foils, fibers and form bodies. 4. Use of the thermoplastic molding compositions according to claim 3 for the production of transparent films and molded parts in Food, automotive, electrical, electronics, construction, con structural and leisure area. 5. Films, fibers and moldings available from the thermoplastic molding compositions according to claims 1 or 2.