SK89794A3 - Mixtures from elastomer polypropylenes and nonolefine thermoplastics - Google Patents

Abstract

Blends of preferably modified elastomeric polypropylene, nonolefinic thermoplastics, such as polyamides (nylon), polystyrene, polycarbamates or polyesters, and preferably a compatibiliser, which is preferably graft-modified elastomeric polypropylene.

Description

Technical field

The invention relates to elastomeric polypropylene (ELPP) blends with neolefin thermoplastics.

BACKGROUND OF THE INVENTION

Mixtures of isotactic polypropylenes (IPPs) and neolefin thermoplastics such as polyamides, polyesters, polystyrene or polycarbonates are known. For example, mixtures of IPP and polyamide are described in EP-A-244,601 or EP-B-261,748. In particular, such mixtures have the advantage that, on the one hand, the advantageous properties of the products made from the mixtures of the individual components can be combined according to the desired product properties profile. On the other hand, the use of conventional cost-effective polypropylenes allows the overall system to be reduced. Thus, for example, typical properties of polypropylenes, such as low water absorption, easy processability and good mechanical properties, can be combined with properties according to the respective type of properties of the non-olefin thermoplastics, such as oxygen barrier, heat resistance and scratch resistance.

The disadvantage of mixtures of neolefin thermoplastics with isotactic polypropylene is mainly due to their high stiffness, which is undesirable in many applications, such as foils, hoses, pleated bags, etc. An alternative to this is the use of elastomer systems, such as amorphous copolymers based on ethylene and propylene (EPR) or ethylene, propylene and dienes (EPDM). However, mixtures with such substances have the disadvantage of a comparatively high viscosity due to the high molecular weight or possibly crosslinked EPR and EPDM structures.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide mixtures which, on the one hand, can be processed into finished products with a low stiffness, expressed as a low modulus E, and on the other hand produce easily flowing low viscosity melts.

The problem could be solved by the polypropylene component of the mixture being polypropylene.

SUMMARY OF THE INVENTION

These drawbacks are overcome by a blend of elastomeric polypropylenes and neolefin thermoplastics according to the invention, which is essentially a blend comprising

a) 5 to 80 wt. %, preferably 10 to 60 wt. %, elastomeric polypropylenes (ELPP),

b) 20 to 95 wt. %, preferably 40 to 90%, of neolefin thermoplastics,

c) 0 to 10 wt. % of an additive to improve compatibility as well as other conventional additives, fillers or reinforcing agents.

Depending on the desired properties, the compositions may additionally comprise other polyolefins, for example based on ethylene, propylene, butene, pentene, hexene or mixtures thereof, such as polyethylene, isotactic, syndiotactic or isotactic homopolymers or copolymers of propylene.

The elastic polypropylenes used for the compositions of the invention are particularly as described, for example, in US 4,33,225, US 4,522,982, and US 5,188,768. This includes both homopolymers and copolymers. The copolymers may contain olefin units, such as ethylene, butene, pentene or hexene units, in addition to propylene units in the molecule. They have a substantially stereospecific block structure of the chain structure and consist, for example, of blocks of isotactic and atactic propylene sequences that are alternately arranged in a polymer chain. They are made by polymerization with the aid of special catalysts, for example according to US 4,355,225, which are obtained by reacting or mixing organic compounds Ti, Zr or Hf with a metal oxide such as Al 2 O 3. T1O2, S1O2 or MgO. Furthermore, elastic polypropylenes can also be produced, for example, analogously to US 4,522,982 using metallocene catalysts in combination with aluminoxanes or analogously to US 5,118,768 using catalysts based on magnesium alkoxides and titanium tetrachloride in the presence of special electron donors.

The Melt Flow Index (MFI) according to ISO 1133 / DIN 53735 at 230 ° C / 2.16kg as a viscosity measure for the ELPPs used is approximately 0.1 to 50 g / 10 min. ELPPs with MFIs greater than one are preferred. It is possible to obtain an ELPP with a higher MFI, corresponding to a lower viscosity, either directly as reaction products or, for example, by chemical degradation, for example with organic peroxide.

For many uses, it is preferred that the ELPP is modified by seeding with unsaturated seeding monomers. Mixtures of vaccinated ELPP and unvaccinated ELPP may also be used. Vaccination degree of the vaccinated ELPP, i. it has a seeding monomer content of approximately 0.1 to 30% by weight. Suitable seeding monomers include, for example, unsaturated mono- and / or dicarboxylic acids, their anhydrides, their esters with aliphatic alcohols and dialkyls containing 1 to 10 carbon atoms, and glycidether, vinyl alcohol ester, as well as vinylaromates or mixtures of these monomers, as well as mixtures of these monomers and olefins containing from 2 to 10 carbon atoms. Especially preferred are grafted monomers from the group of maleic acid, acrylic acid or methacrylic acid or derivatives thereof, as well as from the group of vinyl aromatics such as maleic anhydride (MSA), glycidyl methacrylate (GMA) or styrene.

The seeding reaction proceeds according to the radical seeding copolymerization process described for IPP, for example in EP-A-280.454 or US 4,260,690, by seeding ELPP with ethylenically unsaturated seeding monomers, for example in solution, preferably in aromatic hydrocarbons at a temperature ranging from 50 to 200 ° C. especially in the range from 80 to 150 ° C or in the melt, especially in extruders at a temperature in the range from 180 to 300 ° C, in particular in the range from 200 to 250 ° C. Here, it is advantageous to initiate the formation of radicals on the polymer by radical initiators, such as peroxides or azo compounds and / or high energy radiation, such as gamma radiation and electron radiation.

Suitable synthetic polyolefins, polyesters, polycarbonates, polystyrols, poly (meth) acrylates, polyurethanes, polyoxymethylene, polyethylene oxide, polyphenylene oxide are suitable as neolefin thermoplastics. Preferred neolefin thermoplastics are polyamides, polyesters, polycarbonates and polystyrols.

Suitable compatibility improvers are any known compatibility improvers used for mixtures, for example unsaturated carboxylic acids or derivatives thereof, such as esters, acid halides, anhydrides or acid amides, optionally with unsaturated, carboxylic acids or derivatives thereof with polyolefins. or elastomers grafted with vinylaromates. Additives and compatibility improvements are commercially available, for example, triblock copolymers of styrene-ethylene / butylene-styrene (SEBS), which are optionally grafted with maleic anhydride (Kraton ® R), fa. Shell). Vaccination of modified polypropylenes or elastomers is preferably used as an additive to improve compatibility. Especially preferred are graft-modified elastomeric polypropylenes. Maleic anhydride, glycidyl methacrylate or styrene are used as seeding monomers.

The compositions of the invention may further comprise conventional additives such as process stabilizers and long-term stabilizers, nucleating agents, reinforcing agents and fillers. Preferred fillers are talc, chalk and kaolin. It is preferred, for example, that the compositions according to the invention contain 2 to 50% by weight, in particular 10 to 40% by weight, talc or 1 to 40% by weight. reinforcing fibers, for example glass fibers or carbon fibers.

The compositions according to the invention are characterized by good processability and low rigidity of the finished products. They are used, for example, for the production of films or molded articles by extrusion or injection molding.

The compositions of the invention can be prepared by mixing and homogenizing at a temperature of 180 to 300 ° C in a mixer, plasticizer or extruder.

(a) 5 to 80% by weight of elastomeric polypropylene (ELPP),

(b) 20 to 95% by weight of neolefin thermoplastics;

(c) 0 to 10% by weight, additives to improve compatibility as well as any other conventional additives, fillers or reinforcing agents, if any.

DETAILED DESCRIPTION OF THE INVENTION

Possible methods for making the compositions of the invention are exemplified below.

A. A method for producing elastomeric polypropylene

Example 1:

1.1. Production of catalyst

44.22 g of tetraneolyl zirconium (TNZ; Tm = 66 ° C, Du Ροηχ) of gray-brown color was dissolved in an atmosphere of pure nitrogen in 620 ml of oxygen-free n-hexane on a copper catalyst (BASF R 3-11 catalyst at 70 ° C) and free of water and polar impurities at 20 ° C in a reaction vessel under a shielding gas atmosphere on molecular sieve 4 or 10. The resulting suspension was filtered after 15 minutes after settling the bulk of the insoluble residue on the glass frit in a glass reaction vessel under an inert gas atmosphere equipped with a stirrer, cooled to -40 ° C (heated above 150 ° C and purged with pure nitrogen (containing 0 _2). maximum 2ppm)). The contents of the reaction vessel were further stirred after completion of the filtration (which lasted about 140 minutes) for a further 15 minutes at 40 ° C so that the TNZ would be as quantitative as possible. After settling of the TNF, the residual solution was filtered on a filter plug under nitrogen pressure to another cooled reaction vessel under an inert gas atmosphere. The remaining TNZ was dissolved in an additional volume of 350 mL of N-hexane at about 5-10 ° C for 15 minutes and re-precipitated upon cooling to -34 ° C.

After the TNZ precipitate had settled, the solution was filtered again with nitrogen over a glass filter candle into a reaction vessel with a shielding gas atmosphere with the first mother liquor. Subsequently, TNZ was dried using a vacuum pump (below 1 Pa) with cold precipitation by liquid nitrogen cooling. The purified TNZ had a melting point of 68 ° C and was white to cream. The combined mother liquors were concentrated to about 200 ml and TNZ, which was still in solution, precipitated in the cold at -40 ° C. After further pressure filtration through a filter plug, TNZ was redissolved in 100 mL hexane, reprecipitated at -40 ° C, filtered, and dried under vacuum as described above. The overall yield of this purification process was 82.2%. All processes were performed under pure nitrogen.

A 6-liter reaction flask with four necks was weighed conditioned Α1 0 ^ ₂ (Alumina C, manufactured by DEGUSSA, conditioned at about 800 to 1000 ° C in a stream of nitrogen, and the

16 hours storage at 50% relative atmospheric humidity and 23 ° C air temperature and after repeated drying at 400 ° C under a stream of nitrogen to achieve an optimum surface hydroxylation concentration of about 1 mmol / g Alumina C) and supplemented with 5035 ml n-hexane, Purified on BASF R 3-11 catalyst and molecular sieves 4 and 10, respectively. The suspension was stirred for about 1 hour at 400 rpm. Thereafter, 33.23 g of the above TNZ (without the mother liquor product) was dissolved in 465 ml of n-hexane (purified according to the above procedure) at 20 ° C and this TNZ solution was added dropwise to the Al 2 O 3 suspension with stirring for 50 minutes. whereby the viscosity of the suspension was significantly reduced after the addition of a small amount of TNZ solution. After addition of the TNZ solution, the speed was reduced to about 120 rpm. and stirring was continued for 12.5 hours in the absence of light. To speed up the filtration, the solid catalyst obtained was allowed to settle for 1 hour and finally the solution was filtered by pressure filtration through a sintered glass (3 hours). Subsequently, the solid catalyst was dried under vacuum at a value below 1 Pa (a diffusion oil pump with two interconnected freezing chambers, cooled with liquid nitrogen) with stirring until a constant weight of 292 g. All operations were performed in a pure nitrogen atmosphere. The obtained TNZ / Al 2 O 3 catalyst was an easily filterable beige to light brown powder, which tended to form tiny spheres of about 1 mm in diameter. Zr content was

1.66% wt ..

1.2. polymerization:

A 20 liter double-shell reactor with a paddle stirrer with a polished surface, a thermostat shell, a temperature, speed and torque measurement, heated at 160 ° C and 10 Pa after three vacuum rinses with propane were charged with 7.3 kg of propene at 25 ° C. C. After increasing the number of revolutions to 400 rpm. 10.02 g of the catalyst prepared according to 1 were rinsed with 300 ml of liquid propene (about 20 ° C). 1, and after two minutes the speed was reduced to 260 rpm. Over the next 10 minutes, the temperature of the propene was raised up to 60 ° C and maintained at that temperature for 120 minutes. from the addition of the catalyst. Then the speed was reduced to 200 rpm. and 1880 g of acetone preheated to 50 C were introduced into the reactor over a period of 3 minutes under a nitrogen overpressure. After increasing the speed to 400 rpm. to about 2 minutes and then reduced to 100 rpm. in 60 minutes, unused propene was withdrawn at 60-46 ° C. The remaining acetone slurry of the elastomeric polypropylene ELPP was miscible and could be discharged through a 1 inch diameter reactor bottom opening.

After filtering the ELPP and drying under a stream of nitrogen at 50 ° C, 1.88 kg of a granular, non-sticky ELPP and a melting point (Tm) of 148.1 ° C (measured on a Du Pont 910/20 differential scanning calorimeter (Thermal Analyst 2100)) were obtained. ), the calculated content of 89 ppm and a Zr content of A1 ₂ 0j 0.49% .. ELPP compositions had the MFI (melt flow index according to ISO 1133 / DIN 53735 at 230 ° C / 2.16 kg) of less than 0.01 g / 10 min ..

1.3 Peroxide degradation:

The elastic polypropylene, prepared according to 1.2, was ground on a crusher after cooling below 0 ° C to a grain size of less than 3 mm. Then 0.2% by weight, bis (2-tert-butylperoxoisopropyl) benzene (Perkadox 14SFI, Fa. Akzo), admixed to the amount of polypropylene, was blended, melted at 220 ° C on a 18 mm Brabender single screw extruder and extruded at 1kg. / h through a round nozzle to a 3 mm diameter skein. The residence time in the extruder was about 1 minute. The skein was granulated after solidification in a water bath. The elastic polypropylene was degraded up to an MFI of 25 g / 10 min. The MFI was measured according to ISO 1133 / DIN 53735 at 230 ° C / 2.16 kg.

1.4. vaccinations:

1.4.1. Maleic anhydride vaccination:

In a 2 liter mixer, heated oil bath, with reflux condenser, nitrogen inlet, hermetically sealed stirrer and dropping funnel, was dissolved 50g of elastomeric PP according to 1.3. (MFI: 25) in 1250 mL of xylol (mixture of isomers) under nitrogen atmosphere with stirring at 120 ° C and then 60g of maleic anhydride (MSA) was added. 40 g of benzoyl peroxide dissolved in 100 ml of xylol was added dropwise at 130 DEG C. over 60 minutes. The solution was stirred for an additional 60 minutes and after cooling to 80 ° C was added to 2.5 L of acetone. The precipitated graft copolymer was aspirated, washed in 2.5 L of acetone, aspirated again and dried under vacuum at 80 ° C for 8 hours.

The MSA vaccination degree, determined by infrared spectroscopy, was 1.2% by weight, calculated on the total.

1.4.2: Vaccination with glycidyl methacrylate:

The inoculation was analogous to Example 1.4.1 except that 60 g of glycidyl methacrylate (GMA) was used instead of MSA.

1.4.3. Styrole vaccination:

The inoculation was analogous to Example 1.4.1, but using 60 g of styrene instead of MSA.

B. Method of making mixtures:

The following raw materials were used to produce the mixtures:

polypropylenes

elastomeric

ELPP1, made

ELPP2, made

ELPP3, made

ELPP4, made (ELPP):

according to example 1.3.

according to example 1.4.1 according to example 1.4.2 according to example 1.4.3.

Neolefin thermoplastics:

PA polyamide 6, Miramid SH3, Leuna

PC polycarbonate, Lexan PK1340, General Electrics

PS polystyrol, PS 165H, BASF

PET polyethylene terephthalate, Polyclear G, Hoechst

Comparative polyolefins:

IPP isotactic polypropylene homopolymer, MFI 230 ° C /

216 kg = 10 g / 10 min., Daplen KS 10, PCD polymers,

EPR ethylene-propylene resin, Mooney viscosity:

(ML (1 + 4) 121 ° C), Dutral CO 038, Fa.Enimont

Compatibility enhancements:

W 1 ELPP, vaccinated with MSA according to Example 1.4.1.

W 2 ELPP, vaccinated with GNA according to Example 1.4.2.

W 3 ELPP, styrene inoculated according to Example 1.4.3.

W 4 copolymer SEBS, Kraton G 1652, Shell

VV 5 copolymer SEBS, inoculated MSA, Kraton FG 1901X, Shell

Example 2:

In a Brabender-Plasticorder with plasticizing chamber and pneumatic filling device, a mixture of 20 g (50% by weight) PA, 48 g (45% by weight) of elastomeric polypropylenes (ELPP1) according to Example 1.3 was plasticized for 6 minutes at 260 ° C. and 2 g (5 wt.%) of additives to improve compatibility

W5. The plasticized mixture was then extruded on a Battenfeld hydraulic press at 230 ° C onto 2 mm thick plates to determine the E modulus and rheological properties. The E module was determined by three-point bending according to DIN 53 452/57 on test pieces 80 x 10 x 2 mm. The viscosities were calculated using the Cox-Merz relationship (VP Cox, E. Merz, J. Pol. Sci 28 (1958) 619) from the input and loss modules (measured at 230 ° C in a cone-plate arrangement on a Rheometrics RDS II rheometer) for shear ratios of 10 µm and 100 rad / s. The E-modulus and viscosity values are given in Table 1.

Examples 3 to 9 and Comparative Examples VI to V6:

Analogously to Example 2, mixtures of the raw materials listed in Table 1 were prepared by plasticization

V 6 are not comparative examples according to the invention, in which ELPPs (VI-V4) or elastomers (V5 and V6) as olefin blend components were not used.

When using PET as a neolefin blend component (Examples 8.9, V4), the PET itself was first melted in a heated plasticization chamber at 270 ° C for 2 minutes, then the other components were added and plasticized for a further 5 minutes. The extrusion temperature in the production of the PET test plates was also 270 ° C.

The values of the E modules and the viscosities of the compositions are shown in Table 1. The values show that the compositions of the invention containing ELPP (Examples 2 to 9) have a significantly reduced stiffness, measured as E modulus, than the corresponding mixtures with IPP (comparable Examples). VI to V4, possibly significantly reduced viscosity compared to similar soft elastomer blends (V5 and V6).

Examples 10-13:

Analogously to Example 2, the blends of the raw materials listed in Table 1 were prepared by plasticization. In the case of using PET as a neolefin blend component (Example 13), the plasticization and extrusion temperatures were increased to 270 ° C.

The E-module values are compiled in Table 1 together with the values of the pure neolefin components. In all cases, a significant reduction in stiffness was achieved.

Table 1:

Composition and properties of mass mixtures,)

module

Bending viscosity E (Pa.s) at

Ex. (MPa) 0.01 / s 100 / sec Second 50 % PA 45 % ELPP1 5 % VV5 157 14100 345 3. 50 % PA 45 % ELPP1 5 % VV1 190 15000 330 4th 50 % PC 45 % ELPP1 5 % VV5 135 1570 464 5. ' 50 % PC 45 % ELPP1 5 % W2 151 451 23.4 6th 50 % PS 45 % ELPP1 5 % W4 146 1200 285 7th 50 % PS 45 % ELPP1 5 % W3 164 495 192 8th 50 % PET 45 % ELPP1 5 % VV5 148 8750 94 9. 50 % PET 45 % ELPP1 5 % VV2 156 7000 76.5 VI 50 % PA 45 % IPP 5 % VV5 2018 22600 471 V2 50 % PC 45 % IPP 5 % W5 1306 2520 544 V3 50 % PS 45 % RPP 5 % W4 1586 1700 339 V4 50 % PET 45 % IPP 5 % W5 2011 9500 127 V5 50 % PC 45 % EPR 5 % VV5 100 18700 1420 V6 50 % PS 45 % EPR 5 % W4 107 390000 3780 10 85 % PA 15 % ELPP2 1892 11 85 % PC 15 % ELPP3 1621 12 85 % PS 15 % ELPP4 2409 13 85 % PET 15 % ELPP3 2157 100 9Í PA - 2100 10C 9H PC - 2087 100 9? PS - 3480 100% PET - 2450

Claims (10)

paté claims ’ A mixture of elastomeric propylenes and neolefin thermoplastics, characterized in that it comprises: (a) 5 to 80% by weight. elastomeric polypropylenes (ELPP), b) 20 to 95% hmoT. neolefin TermoplasTov, c) 0 to 10% hmoT. Compatibility enhancers as well as any other conventional additives, fillers or reinforcing agents, if any. A composition according to claim 1, characterized in that it comprises: (a) 10 to 60% by weight of elastomeric polypropylene (ELPP); (b) 40 to 90% by weight of neolefin thermoplastics; (c) 0 to 10% by weight, additives to improve compatibility as well as any other conventional additives, fillers or reinforcing agents, if any. Composition according to claim 1 or 2, characterized in that the ELPPs are modified by seeding with unsaturated seeding monomers. Composition according to claims 1 to 3, characterized in that the ELPP consists of a mixture of vaccinated ELPPs and unvaccinated ELPPs. Composition according to one of Claims 1 to 4, characterized in that the elastomeric polypropylenes have a melt flow index (MFI) at 230 ° C / 2.16 kg of greater than 1. A composition according to claims 1 to 5, characterized in that the non-olefin thermoplastics are polyamides, polystyrols, polycarbonates or polyesters. A composition according to claims 1 to 6, characterized in that the additive for improving compatibility is a polypropylene or an elastomer modified by seeding. Composition according to claim 7, characterized in that the additive for improving compatibility is an inoculated modified elastomeric polypropylene. Composition according to one of Claims 1 to 8, characterized in that talc, chalk or kaolin are used as fillers. Method for producing mixtures according to one of Claims 1 to 9, characterized in that it is mixed and homogenized at 180 to 300 ° C in a mixer, plasticizer or extruder. a) ^_ 5 to 80% by weight of elastomeric polypropylenes (ELPP), (b) 20 to 95% by weight of neolefin thermoplastics; (c) and up to 10% by weight, additives to improve compatibility, and optionally, other conventional additives, fillers or reinforcing agents.