WO2004106391A1

WO2004106391A1 - Polymer-based material

Info

Publication number: WO2004106391A1
Application number: PCT/EP2004/003941
Authority: WO
Inventors: Matthias Koch
Original assignee: Merck Patent Gmbh
Priority date: 2003-06-02
Filing date: 2004-04-15
Publication date: 2004-12-09
Also published as: DE10324892A1; TW200516086A

Abstract

The invention relates to a polymer-based material which essentially consists of a polymer matrix in which at least one type of fluoride polymer is intercalated and is characterised in that metal oxide particles are homogeneously and nano-dispersely distributed in said polymer matrix. The production and use of the inventive material are also disclosed.

Description

Polymer-based material

The present invention relates to a polymer-based material, its production and use. 5

For use in bearings in the technical field mainly metallic materials are used, the use of polymer-based materials significant here advantages in weight and • _j o processability promises.

The use of polymer-based materials for artificial joints or joint implants is already established. Different materials and are used for artificial joints or joint implants

15 material combinations are used, which differ mainly in price and durability. Combinations of a suitable metal alloy with ultra-high molecular weight polyethylene (UHMWPE) are among the inexpensive approaches that make up the mass of the 0 implants. These “metal-on-polymer” joint implants are described, for example, in WO 01/17464 (Depuy Int. Ltd.). A disadvantage of the metal-UHMWPE combination is the static friction between the metal and the plastic, which makes the plastic part 5 susceptible to wear is and the sensitivity of the UHMWPE ^" against installation errors and damage during installation, eg. B. by contamination with bone particles or bone cement.

Mixtures of polytetrafluoroethylene with ethylene-propylene copolymers 0 are known from European patent application EP-A-1 199 991.

From the European patent EP-B-0 124 955 the use of

Mixtures of polyolefins with polytetrafluoroethylene for controlling the 5 friction and wear properties of a polymeric matrix are known.

The coefficient of friction of the polymer matrix is determined by the addition decreased. However, it has been shown that the strength and hardness of such polytetrafluoroethylene composites are significantly worse than that of the unfilled materials.

The object of the present invention is therefore to provide a polymer-based material and a method for the same

Manufacture which at least partially eliminates the disadvantages of the prior art in that the material in sliding pairs, such as sliding bearings, joint implants or artificial joints, enables reduced friction between two sliding partners while at the same time improving the strength of the material.

A first object of the present invention is therefore a polymer-based material which is essentially composed of a

Polymer matrix in which at least one fluorinated polymer is embedded and which is characterized in that in the polymer matrix

Metal oxide particles are nanodisperse and homogeneously distributed.

In the metal oxide particles according to the invention, metal means all elements which can occur as electropositive partners in comparison to the counterions, such as the classic metals of the subgroups or the main group metals of the first and second main groups, but also all elements of the third main group as well as silicon, germanium, Tin, lead, phosphorus, arsenic, antimony and bismuth. The preferred metal oxides include in particular titanium, zinc, zirconium, cerium or silicon dioxide.

According to the invention, these metal oxide particles are preferably functionalized with non-acidic nucleophiles such as polyether chains.

The material usually contains 0.1-25% by weight, in particular 0.5-15% by weight and particularly preferably 1-5% by weight of metal oxide particles. For the use of the metal oxide particles in the sense of the present invention, it has proven to be advantageous in particular with regard to the abrasion properties if the particles are round and have no edges; in the sense of the present invention that the ratios of the three mutually perpendicular diameters of the particles are in the range 1: 2 to 2: 1 and preferably in the range 1.5: 1 - 1: 1.5.

It is also advantageous if the particles are not porous; i.e. the surface of the particles is essentially formed by their outer surface.

In addition, in terms of the abrasion properties and processability, it is advantageous if the metal oxide particles have a particle size distribution in which the proportions of particles with a particle diameter above 500 nm are less than 0.5% by weight, preferably the proportions of particles with a particle diameter above 100 nm are below 0.5% by weight and particularly preferably the proportions of particles with a particle diameter above 50 nm are below 0.5% by weight.

In a variant of the present invention, the metal oxide particles used are preferably monodisperse cores made of silicon dioxide, which can be obtained, for example, by the process described in US Pat. No. 4,911,903. The cores are produced by hydrolytic polycondensation of tetraalkoxysilanes in an aqueous-ammoniacal medium, firstly producing a sol of primary particles and then bringing the SiO2 particles obtained to the desired particle size by continuous, controlled metering in of tetraalkoxysilane. Are using this procedure monodisperse Si02 cores can be produced with a standard deviation of the average particle diameter of 5%.

SiO cores which are coated with (semi) metals or non-absorbent metal oxides, such as TiO ₂ , ZrO ₂ , ZnO ₂ , SnO ₂ or Al ₂ O ₃ , are furthermore preferred as the starting material. The production of SiO ₂ cores coated with metal oxides is described in more detail, for example, in US Pat. No. 5,846,310, DE 19842 134 and DE 19929 109. 0

Monodisperse cores made of metal oxides such as TiO ₂ , Zr0 ₂ , Zn0 ₂ , SnO ₂ or Al ₂ O ₃ or metal oxide mixtures can also be used as the starting material. Their production is described for example in EP 0 644 914 g. Furthermore, the process according to EP 0 216 278 for the production of monodisperse SiO ₂ cores can be transferred to other oxides easily and with the same result. Tetraethoxysilane, tetrabutoxytitanium, tetrapropoxyzirconium or their mixtures are added in one pour with intensive mixing to a mixture of alcohol, water and ammonia, the temperature of which is adjusted to 30 to 40 ° C. with a thermostat, and the mixture obtained for a further 20 seconds intensely stirred, whereby a suspension of monodisperse nuclei in the nanometer range is formed. 5 After a post-reaction time of 1 to 2 hours, the cores are separated off, washed and dried in the customary manner, for example by centrifugation.

Q Fluorinated polymers are used as a further additive. In general, all polymeric materials in which there is a corresponding fluorination are suitable. In particular, these can be polytetrafluoroethylene (PTFE), polytrifluorochloroethylene and copolymers, the corresponding

Units included. The fluorinated polymers in the 5th

Material usually contain 1-50 wt .-%, in particular 5-30 wt .-% and particularly preferably 10-25 wt .-%. All types of polymers are generally suitable as the polymer matrix. With regard to the intended use for sliding pairs according to the invention, however, polyolefins, polyamides and polyether ether ketones are preferred.

Polyamides are in particular the polymers known under the names nylon-6 and nylon-6,6, which can be obtained by customary methods which are known to the person skilled in the art.

Polyetheretherketones are high-strength and temperature-resistant thermoplastics, which are made from 4,4'-difluobenzophenone and dipotassium hydroquinone.

Polyolefins are generally understood to mean macromolecular compounds which can be obtained by polymerizing substituted or unsubstituted hydrocarbon compounds with at least one double bond in the monomer molecule.

Olefin monomers preferably have a structure according to the formula R1CH = CHR2, where R1 and R2 can be the same or different and are selected from the group consisting of hydrogen and the cyclic and acyclic alkyl and aryl or alkylaryl radicals with 1 to Contains 20 carbon atoms.

Usable olefins are monoolefins, such as ethylene, propylene, but-1-ene, pent-1-ene, hex-1-ene, oct-1-ene, hexadec-1-ene, octadec-1-ene, 3- Methylbut-1-ene, 4-methylpent-1-ene, 4-methylhex-1-ene, diolefins such as 1, 3-butadiene, 1, 4-hexadiene, 1, 5-hexadiene, 1, 6-hexadiene, 1 , 6-octadiene, 1, 4-dodecadiene, aromatic olefins, such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, m-chlorostyrene, p-chlorostyrene, indene, vinylanthracene, vinylpyrene, 4-vinylbiphenyl, dimethano-octahydro-naphthalene, acenaphthalene, vinyl fluorene, Vinyl chryses, cyclic olefins and diolefins, such as cyclopentene, 3-vinylcyclohexene, dicyclopentadiene, norbornene, 5-vinyl-2-norbornene, tert.-ethylidene-2-norbornene, 7-octenyl-9-borabicyclo-

(3,3,1) nonane, 4-vinylbenocyclobutane, tetracyclododecene and further for example acrylic acid, methacrylic acid, methyl methacrylate, ethyl acrylate, acrylonitrile, 2-ethylhexyfacrylate, methacrylonitrile, maleimide, N-phenyl-maleimide, vinylsilane, trimethylallylsilane, vinyl chloride, vinyl chloride, vinyl chloride, vinyl chloride , Isobutylene.

Particularly preferred are the olefins ethylene, propylene and generally further 1-olefins, which are either polymerized or copolymerized in mixtures with other monomers.

The use of polyethylene (PE) as the material for the polymer matrix is particularly preferred. High molecular weight PE is preferred as PE

(UHMWPE), which is generally extremely high

Molecular weight between 3.9 and 10.5 million g / mol. With increasing molar mass, some technically important properties of polyethylenes improve, e.g. Wear resistance, impact strength,

Dimensional stability under the influence of heat and lubricity. At the same time, the processability of the high-molecular PE decreases. It is therefore also an object of the invention to be able to use a well processible PE in the composites, with which similarly good or better properties can be achieved than with the PE previously used.

The surface of the metal oxide particles preferably has oligomeric or polymeric structures which contain non-acidic, nucleophilic groups. Again, these are preferably polymers (with oligomers in the following basically with less than

The term polymer is to be understood) which are grafted or polymerized onto the surface, that is to say are synthesized on the surface. The

Polymers can be branched or unbranched; in a preferred In one embodiment, the polymers have a linear structure. The non-acidic, nucleophilic groups can be contained directly in the main chain or in the form of functional groups or small molecules as a side chain. The polymers can either be grafted directly onto the optionally functionalized surface or polymerized on, that is to say synthesized on the surface, or via a spacer with the

Surface connected. In a preferred embodiment of the

Invention, the spacer is an inert polymer such as

10 polyethylene, polypropylene or polystyrene or a cyclic or acyclic low molecular weight hydrocarbon compound, particularly preferably an alkyl chain with 1-20 C atoms. The polymer containing non-acidic, nucleophilic groups is preferably

A _{K is} a polyether, such as in particular polyethylene oxide, polypropylene oxide or mixed polymers of ethylene and propylene oxide, or um

Polyvinyl alcohol, a polysaccharide or a polycyclodextrin.

It is particularly preferred according to the invention if the

Metal oxide particles are functionalized with polyethylene oxide. 0

According to the invention, these oligomeric or polymeric structures are applied to the metal oxide particles after their formation. In order to apply the oligomeric or polymeric structures to the surface of the cores 5, as already stated above, it can be advantageous if the surface of the cores is functionalized. A method in which the surface of the cores is functionalized before the oligomeric or polymeric structures are applied is therefore preferred according to the invention. In particular, it may be preferred to apply chemical functions on the surface which, as the active chain end, enable the jacket polymers to be grafted on. Examples here are, in particular, terminal double bonds, halogen functions, epoxy groups and polycondensable groups. The

35

Functionalization take place directly during particle production. In a preferred embodiment, functionalized ones are used Silicon dioxide particles corresponding to those described in EP-A-216 278

Method by using trialkoxysilanes that already have the desired

Wear group for surface functionalization. The

Modification of surfaces which carry hydroxyl groups is known for example from EP-A-337 144. Other methods of

Modification of particle surfaces are well known to the person skilled in the art, in particular from the production of chromatography materials, and in various textbooks such as Unger, K.K., Porous Silica, Elsevier

10 Scientific Publishing Company (1979).

In order to achieve a nanodisperse and as homogeneous as possible distribution of the metal oxide particles in the polymer matrix, it is advantageous to incorporate them already during the polymerization process. UHMWPE in particular is usually not extruded, but processed by hot pressing. Subsequent addition of fillers does not lead to the desired even distribution.

0

Another object of the present invention is therefore a

Process for the production of a polymer-based material essentially composed of a polymer matrix in which at least one granulate of at least one fluorinated polymer and metal oxide particles are embedded 5, which is characterized in that the metal oxide particles and the at least one fluorinated polymer are already present during the

Polymerization process of the polymer matrix are integrated into the matrix.

30

For the incorporation of the metal oxide particles into the polymer matrix during the polymerization process, different ways (or combinations thereof) can be labeled with suitable functionalizations. The metal oxide particles can e.g. if the polymer

35 Matrix formed from polyolefins is loaded with metallocenes and then used for polymerization. Likewise, instead of Metallocenes after loading with a polymerization-active species

Ziegler-Natta (e.g. TiCI) or Phillips possible. The polymer matrix is created around the particles, which results in a better distribution than subsequent mixing in the extrusion process.

Functionalization of the metal oxide particles with nucleophilic, non-acidic compounds, for example polyethers, enables the direct support of methylaluminoxane (MAO) -activatable compounds; primarily that of metallocenes. The functionalized particles form a gel together with MAO through coordinative interactions. The metallocene is thus bound to the support via the MAO. A homogeneous distribution of carrier and polymerization-active species is achieved. After drying, the catalyst can be used directly for the polymerization.

Usual catalyst systems for the polymerization of olefins consist of a compound of a transition metal from the 3rd to 8th subgroup of the periodic table and a cocatalyst which is usually an organometallic compound of a (semi-) metal of the 3rd or 4th main group of the periodic table.

The compound of a transition metal from subgroup 3 to 8 of the periodic table, which is also referred to below as "catalyst", is preferably a complex compound, particularly preferably a metallocene compound. In principle, it can be any metallocene. Bridged (ansa-) and unbridged metallocene complexes with (substituted) p ligands such as cyclopentadienyl, indenyl or fluorenyl ligands are conceivable, with symmetrical or unsymmetrical complexes with central metals from the 3rd to 8th group. The elements titanium, zirconium, hafnium, vanadium, palladium, nickel, cobalt, iron and are preferably used as the central metal Chromium used, with titanium and in particular zirconium being particularly preferred.

Suitable zirconium compounds are, for example:

B s (cyclopentadienyl) zirconium monochloride monohydride, B s (cyclopentadienyl) zirconium monobromide monohydride, B s (cyclopentadienyl) methylzirconium hydride, B s (cyclopentadienyl) ethyl zirconium hydride, B s (cyclopentadylzirconium cyclohexadylzirconium) s (cyclopentadienyl) phenylzirconium hydride, B s (cyclopentadienyI) benzylzircroniuπvhydrid, B s (cyclopentadienyl) neopentylzirconium hydride, B s (methylcyclopentadienyl) zirconium monochloride monohydride, B s (indenylylochloride) ) zirconium dichloride, B s (cyclopentadienyl) zirconium dibromide, B s (cyclopentadienyl) methyIzirconium monochloride, B s (cyclopentadienyl) ethylzirconium monochloride, B s (cyclopentadienyl) cyclohexylzirconien (monochloridophenylidyl chloride), B s (cyclopentadienyl) benzylzirconium monochloride, B s (methylcyclopentadienyl) zirconium dichloride, B s- (1, 3-dimethylcyclopentadienyl) zirconium dichloride, B s (n-butylcyclopentadienyl) zirconium dichioride, B s (n-propyl pentadienyl) zirconium dichloride, B s (iso-butylcyclopentadienyl) zirconium dichloride, B s (cyclopentylcylopentadienyl) zirconium dichloride, B s (octadecylcyclopentadienyl) zirconium dichloride, B s (indenyl) zirconium zirconium -dibromide, B s (indenyl) zirconium dimethyl, B s (4,5,6,7-tetrahydro-1-indeny!) dimethyl zirconium, Bis (cyclopentadienyl) zirconium diphenyl,

Bis (cyclopentadienyl) dibenzylzirconium,

Bis (cyclopentadienyl) methoxyzirconium chloride,

Bis (cyclopentadienyl) ethoxyzirconium chloride, 5

Bis (cyclopentadienyl) butoxyzirconium chloride,

Bis (cyclopentadienyl) 2-ethylhexoxyzirconium chloride,

Bis (cyclopentadienyl) methylzirconium ethoxide,

Bis (cyclopentadienyl) methyl zirconium butoxide, 10 bis (cyclopentadienyl) ethyl zirconium ethoxide,

Bis (cyclopentadienyl) phenylzirconium ethoxide,

Bis (cyclopentadienyl) benzyIzirconium ethoxide,

Bis (methylcyclopentadienyl) ethoxyzirconium chloride, A c bis (indenyl) ethoxyzirconium chloride,

Bis (cyclopentadienyl) ethoxyzirconium,

Bis (cyclopentadienyl) butoxyzirconium,

Bis (cyclopentadienyl) 2-ethylhexoxyzirconium,

Bis (cyclopentadienyl) phenoxyzirconium monochloride, 0

Bis (cyclopentadienyl) cyclohexoxyzirconium chloride,

Bis (cyclopentadienyl) phenylmethoxyzirconium chloride

Bis (cyclopentadienyl) methylzirconium-phenylmethoxid

To (cyclopentadiphenyl) trimethylsiloxyzirconium chloride, 5 bis (cyclopentadienyl) triphenylsiloxyzirconium chloride, bis (cyclopentadieny!) ThiophenyIzirconium chloride, bis (cyclopentadienyl) neoethylzirconium chloride, bis (cyclopentadienyl) bis (dimethylamide) zirconium, ₀ to (cyclopentadienyl) diethylamidezirconium -chloride,

Dimethylsilylenebis (4 ₎ 5,6,7-tetrahydro-1-indenyl) zirconium dichloride, dimethylsilylenebis (4,5,6,7-tetrahydro-1-indenyl) dimethylzirconium, dimethylsilylenebis (2-methyl-4,5-benzoindenyl) zirconium dichloride, dimethylsilylenebis (4-tert-butyl-2-methylcyclopentadienyl) zirconium dichloride, dimethylene silylbis (4-tert-butyl-2-methylcyclopentadienyl) dimethylzirconium, Ethylenebis (indenyl) ethoxyzirconium chloride,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) ethoxyzirconium chloride,

Ethylenebis (indenyl) dimethylzirconium,

Ethylenebis (indenyl) diethylzirconium,

Ethylenebis (indenyl) diphenylzirconium,

Ethylenebis (indenyl) dibenzylzirconium,

Ethylenebis (indenyl) methylzirconium monobromide-,

Ethylene bis (indenyl) ethyl zirconium monochloride, ethylene bis (indenyl) benzyl zirconium monochloride,

Ethylenebis (indenyl) methylzirconium monochloride,

Ethylenebis (indenyl) zirconium dichloride,

Ethylene bis (indenyl) zirconium dibromide, ethylene bis (4,5,6,7-tetrahydro-1 -indenyl) dimethyl zirconium,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) methylzirconium monochloride,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dibromide,

Ethylenebis (4-methyl-1-indenyl) zirconium dichloride,

Ethylenebis (5-methyl-1-indenyl) zirconium dichloride,

Ethylenebis (6-methyl-1-indenyl) zirconium dichloride,

Ethylenebis (7-methyl-1-indenyl) zirconium dichloride,

Ethylene bis (5-methoxy-1-indenyl) zirconium dichloride, ethylene bis (2,3-dimethyl-1-indenyl) zirconium dichloride,

Ethylenebis (4,7-dimethyl-1-indenyl) zirconium dichloride,

Ethylenebis (4,7-dimethoxy-1-indenyl) zirconium dichloride,

Ethylene bis (indenyl) zirconium dimethoxide, ethylene bis (indenyl) zirconium diethoxide,

Ethylenebis (indenyl) methoxyzirconium chloride,

Ethylenebis (indenyl) ethoxyzirconium chloride,

Ethylenebis (indenyl) methylzirconium ethoxide,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dimethoxide,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium diethoxide,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) methoxyzirconium chloride, Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) ethoxyzirconium chloride,

Ethylenebis (4,5,6,7-tetrahydro-1-indenyl) methylzirconium ethoxide,

Ethylene bis (4,5,6,7-tetrahydro-1-indenyl) dimethyl zirconium, isopropylene (cyclopentadienyl) (1-fluorenyl) zirconium dichloride,

5

Diphenylmethylene (cyclopentadienyl) (1-fluorenyl) zirconium dichloride.

Suitable titanium compounds are, for example:

Bis (cyclopentadienyl) titanium monochloride monohydride, 10 bis (cyclopentadienyl) methyltitanium hydride,

Bis (cyclopentadienyl) phenyl titanium chloride,

Bis (cyclopentadienyl) benzyltitanium chloride,

Bis (cyclopentadienyl) titanium dichloride, Λ c bis (cyclopentadienyl) dibenzyl titanium,

Bis (cyclopentadienyl) ethoxytitanium chloride,

Bis (cyclopentadienyl) butoxy chloride,

Bis (cyclopentadienyl) titanium methyl ethoxide,

Bis (cyclopentadienyl) phenoxytitanium chloride, 0

Bis (cyclopentadienyl) trimethylsiloxytitan chloride,

Bis (cyclopentadienyl) thiophenyltitan chloride,

Bis (cyclopentadienyl) bis (dimethylamide) titanium,

Bis (cyclopentadienyl) ethoxytitanium, 5 bis (n-butylcyclopentadienyl) titanium dichloride,

To (cyclopentylcylopentadienyl) titanium dichloride,

(Indenyl) titanium dichloride,

Ethylene bis (indenyl) titanium dichloride ₀ ethylene bis (4,5,6,7-tetrahydro-1-indenyl) titanium dichloride and

Dimethylsilylene (tetramethylcyclopentadienyl) (tert-butylamide) titanium dichloride.

Suitable hafnium compounds are, for example: bis (cyclopentadienyl) hafnium monochloride monohydride, 5 bis (cyclopentadienyl) ethyl hafnium hydride, bis (cyclopentadienyl) phenyl hafnium chloride, Bis (cyclopentadienyl) hafnium dichloride,

Bis (cyclopentadienyl) hafnium benzyl,

Bis (cyclopentadienyl) ethoxyhafnium chloride,

Bis (cyclopentadienyl) butoxyhafnium chloride,

Bis (cyclopentadienyl) methylhafnium ethoxide,

Bis (cyclopentadienyl) phenoxyhafnium chloride,

Bis (cyclopentadienyl) thiophenylhafnium chloride,

Bis (cyclopentadienyl) bis (diethylamide) hafnium, ethylene bis (indenyl) hafnium dichloride,

Ethylenebis (4,5,6,7-tetrahydro-1 -indenyl) hafnium dichloride and

Dimethylsilylenebis (4,5,6,7-tetrahydro-1-indenyl) hafnium dichloride.

Suitable iron compounds are, for example:

2,6- [1- (2,6-diisopropylphenylimino) ethyl] pyridine iron dichloride, 2,6- [1- (2,6-dimethylphenylimino) ethyl] pyridine iron dichloride

Suitable nickel compounds are, for example: (2,3-bis (2,6-diisopropylphenylimino) butane) nickel dibromide, 1,4-bis (2,6-diisopropylphenyl) acenaphthenediimine nickel dichloride, 1,4-bis (2,6 -diisopropylphenyl) acenaphthendiiminnickel dibromide.

Suitable palladium compounds are, for example:

(2,3-bis (2,6-diisopropylphenylimino) butane) palladium dichloride and (2,3-bis (2,6-diisopropylphenylimino) butane) dimethyl palladium.

The use of zirconium compounds is particularly preferred, the compounds bis (cyclopentadienyl) zirconium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, ethylene bis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride and bis (1,3-dimethylcyclopentadienyl) zirconium dichloride are particularly preferred. When connecting a transition metal from the 3rd to the 8th

Subgroup according to the invention can, however, also be a classic Ziegler-Natta compound, such as titanium tetrachloride,

Tetraalkoxytitanium, alkoxytitanium chlorides, vanadium halides,

Vanadium oxide halides and alkoxyvanadium compounds in which the

Alkyl radicals have 1 to 20 carbon atoms.

According to the invention, both pure transition metal compounds and mixtures of different transition metal compounds can be used, mixtures of metallocenes or Ziegler-Natta compounds with one another and mixtures of metallocenes with Ziegler-Natta compounds being advantageous.

In the case of catalysts according to Ziegler-Natta, the polymerization-active compound can be applied directly to the metal oxide particles, if appropriate with the addition of magnesium chloride, by known processes (for example as TiCl ₄ vapor).

The polymerization is carried out in a known manner in solution, suspension or gas phase polymerization, continuously or batchwise, with gas phase and suspension polymerization being expressly preferred. Typical temperatures during the polymerization are in the range from 0 ° C. to 200 ° C., preferably in the range from 20 ° C. to 140 ° C.

Catalysts which are customarily used for polyolefin production and are designed for high productivity can also be used by "diluting" them with appropriately treated metal oxide particles. Here, olefin-functionalized particles are preferred

Use on whose surface there are no more reactive groups. The deactivation takes place on the one hand by the Olefin functionalization and, moreover, by treatment with aluminum alkyls, for example diisobutylaluminium hydride.

Alternatively, the metal oxide particles can also be anchored in the polymer matrix via alkyl or olefinic functions on the metal oxide surface, which are incorporated as copolymers in the polymer in order to achieve particularly good anchoring. Molecules such as

A _: Si XD

B

used, where A represents an alkoxy group, preferably ethoxy or methoxy, B represents the same alkoxy or alkyl group, preferably methyl and D represents a hydrocarbon with at least one terminal alkyl function, preferably a linear alkyl chain with terminal double bond.

X is either a direct or a heteroatom-containing compound such as (CH ₂ ) _n -0-, where n is between 1 and 5.

For the alkyl functions, molecules like

^B ,

A Si X C

B is used, where A is an alkoxy group, preferably ethoxy or methoxy, B is such an alkoxy or alkyl group, preferably methyl and C is a

Alkyl chain of length 1-25, preferably 10-20 represents.

X is either a direct or a heteroatom-containing compound such as (CH ₂ ) _π -0-, where n is between 1 and 5. 5

As stated above, the polymer-based materials according to the invention are suitable for use in sliding pairs.

10 The present invention therefore also relates to the use of a polymer-based material according to the invention or produced according to the invention for the production of joint implants in the medical-technical field or

^ 5 Use for the manufacture of sliding pairs, in particular ball bearings, roller bearings, sliding bearings, link chains, gear wheels in the technical field, as well as the corresponding products. In particular, there are a pair of glides in which the sliding partners consist of metallic, polymeric and / or ceramic materials, which are characterized in that at least one of the sliding partners essentially consists of a polymer-based material according to the invention or produced according to the invention and an artificial joint of a prosthesis in which the Joint partners made of metallic, polymeric 5 and / or ceramic materials, which are characterized in that at least one of the joint partners consists essentially of a polymer-based material according to the invention, further objects of the present invention. _Q sliding pairs for technical use can assume all known embodiments. The following are particularly worth mentioning:

- Bearings,

- Roller bearing,

Ball bearings, it being particularly preferred that the sleeve be made of the polymer-based material, - link chains and

- gear wheels.

In prostheses with artificial joints can be due to the required compatibility with human or animal

Tissue, the so-called biocompatibility, and the high frictional load on the joint partners, only a few materials are used. Of the metallic materials, cobalt-chrome (CoCrMo) in particular has proven its worth. Applications of titanium-based alloys or surface-modified titanium alloys (e.g. titanium nitride) are still in the experimental stage. Of the plastics in particular polyethylene (UHMWPE) is used in the cups of the hip joint endoprostheses and as a sliding partner of the shin component and aluminum oxide and zirconium oxide are the usable ceramic materials. Wear within the artificial joint is minimized by the simultaneous incorporation of hard, non-porous metal oxide particles and fluorinated polymers in the PE molded part.

The following examples are intended to illustrate the present invention without restricting it.

Beispieie

Example 1: Production of the functionalized silica particles

a) Functionalization of the nanoparticles (Monospheres®20 (Merck))

16.1 g of Monospheres®20 (Merck, average diameter of the spherical Si0 ₂ particles: 20 nm, standard deviation of the average particle size <5%) are suspended in 300 ml of water and a solution of 2.44 g ( 12.34 mmol) of trimethoxychloropropylsilane in 25 ml of ethanol are slowly added dropwise. The dispersion is heated to reflux for 24 h. The functionalized monospheres are then cleaned by ultrafiltration. The resulting powder is dried in vacuo.

b) grafting the polyethylene oxide chains

2.68 g of polyethylene oxide-350 (M = 350 g / mol) are slowly added to 221 mg of sodium hydride in 50 ml of tetrahydrofuran at 0 ° C. The mixture is then stirred at 0 ° C. for 30 min and at room temperature for a further 30 min. The solution is added to a suspension of 5 g of the chloropropoxy-functionalized Monospher® 20 (from Example 1a) in tetrahydrofuran using a syringe. After stirring for 12 h, the solvent is removed and the residue is washed three times with ethanol.

Example 2: Supported Metallocene Polymerization

2 g of polyethylene oxide-functionalized monospheres (from Example 1) are stirred with 4 ml of a solution of methylaluminpane in toluene (w (MAO) = 5%) for two hours, and with 0.2 ml of a solution of dicyclopentadienylzirconium dichloride in the above MAO solution ( c (Zr) = 0.05 mol / l) added. After 30 minutes of stirring, the solvent is in

Vacuum removed. What remains is a yellow colored, flowing powder which is used directly for the polymerization. (Loading: 2.3 μmol Zr / g Kat, Al / Zr = 630.)

For the polymerization, 960 mg of the above catalyst and 700 mg of PTFE are injected at 70 ° C. into a 1 liter steel reactor filled with 400 ml of isobutane and brought to 36 bar with ethene through a lock by means of argon overpressure. After 10 minutes, the polymerization is terminated by releasing the pressure. Yield: 8.6 g of colorless, free-flowing powder.

Example 3: Preparation of cis-silanized monospheres

In a 500 ml three-necked flask, 132g monospheres be presented ^® 20- dispersion and 150g ethanol. The mixture is heated to 70 ° C. and, with vigorous stirring, 12.7 g of ethanolic silane solution are added dropwise over a period of 20 min using a dropping funnel. It is important to ensure that the solution is introduced at the edge of the vessel, but does not come into contact with its wall.

The mixture is then boiled under reflux for 20 h. The suspension is then cleaned by means of ultrafiltration and the solvent is removed in vacuo.

Example 4: Metallocene Polymerization

10 g of the octadodecyl-functionalized monospheres produced in Example 3 and 40 g of PTFE in 400 ml are placed in a steel reactor Isobutane submitted. The reactor is heated to 70 ° C and brought to 36bar with ethene. 80 mg of silica-supported dicyclopentadienyl zirconium dichloride are injected through a sluice using argon overpressure. After 60 minutes, the reaction is stopped by releasing the pressure. Yield: 78 g of colorless granules (0.5-1 mm particle diameter).

Example 5: Ziegler-Natta polymerisation

a) Catalyst production:

2.50 g of a dried magnesium chloride / silica carrier (Sylopol ™ 948; Grace) are suspended in a Schlenck flask in 62.5 mL hexane and stirred for 12 h with 2.35 mL dibutyl magnesium (Aldrich). Then 0.34 mL titanium tetrachloride are added and the mixture is stirred for a further 3 h. The supported catalyst is then filtered off and dried in vacuo.

b) polymerization

150 mg of the octadodecyl-functionalized monospheres prepared in Example 3 and 750 mg of PTFE (Teflon ™; Aldrich) and 20 mg of the supported catalyst from Example 5a) in 100 mL of heptane are placed in a pressure reactor. The reactor is heated to 70 ° C. and brought to 5 bar with ethene. After 15 minutes, the reaction is stopped by releasing the pressure. Yield: 5.24 g of colorless granules

Comparative tests:

The following are prepared as in Example 5:

Comparative Example 1: PE without the addition of PTFE and silica

Comparative Example 2: PE / silica without the addition of PTFE

Comparative Example 3: PE / PTFE without the addition of silica abrasion tests

The abrasion was determined with a pin-disc test bench. A 20cm high and 6mm high pressure cylinder

Diameter was pressed at 20C with a constant force of 50N onto a disc made of polished stainless steel rotating at 0.95m / s. The

Abrasion results from the loss of length of the cylinder compared to

Running Tracke.

surface hardness

The surface hardness was checked using a commercially available measuring device set to Shore-D.

The following values were measured:

The example according to the invention shows increased hardness compared to the PTFE-treated product (comparative example 3) and increased abrasion resistance compared to the untreated or the silica-treated product. The product according to the invention thus combines the self-lubricating properties of the PTFE-containing materials with the hardness of silica-containing materials.

Claims

claims

1. Polymer-based material built up essentially from one

Polymer matrix in the at least one fluorinated polymer

5 is embedded, characterized in that metal oxide particles are nanodisperse and homogeneously distributed in the polymer matrix.

2. Polymer-based material according to claim 1, characterized in that the metal oxide particles are selected from

Titanium, zinc, zirconium, cerium or silicon dioxide and the metal oxide particles are preferably functionalized with non-acidic nucleophiles such as polyether chains and the material is preferably 0.1-525% by weight, in particular 0 , 5 - 15 wt .-% and particularly preferably 1 - 5 wt .-% metal oxide particles.

Polymer-based material according to claim 2, characterized in that the metal oxide particles are functionalized with polyethylene oxide chains.

4. Polymer-based material according to claim 2, characterized in that alkyl and / or olefin-functionalized 5 metal oxide particles are used.

Polymer-based material according to at least one of the preceding claims, characterized in that it is

30 at least one fluorinated polymer is polytertrafluoroethylene and the material preferably contains 1-50% by weight, in particular 5-30% by weight and particularly preferably 10-25% by weight of fluorinated polymer.

35

6. Polymer-based material according to at least one of the preceding claims, characterized in that the polymer matrix is essentially formed from polyolefins, polyamides and / or polyether ether ketones, polyolefins which are obtained by homo- or copolymerization from 1-olefin monomers, such as in particular Ethylene and / or propylene are preferred, and the polymer matrix is particularly preferably formed essentially from high molecular weight polyethylene. 0

7. Polymer-based material according to at least one of the preceding claims, characterized in that the metal oxide particles have a particle size distribution in which the proportions of particles with a particle diameter 5 above 500 nm are less than 0.5% by weight, preferably the proportions of particles with a particle diameter above 100 nm are below 0.5% by weight and particularly preferably the proportions of particles with 0 particle diameter above 50 nm are below 0.5% by weight.

8. A method for producing a polymer-based material 5 essentially composed of a polymer matrix in which at least one granulate of at least one fluorinated polymer and metal oxide particles are embedded, characterized in that the metal oxide particles and the at least one fluorinated _Q polymer are already in the process the polymerization process of

Polymer matrix can be integrated into the matrix.

9. The method according to claim 8, characterized in that polyethylene oxide-functionalized silica particles as 5

Catalyst carrier can be used.

10. The method according to claim 8, characterized in that a polymerization-active species of the Ziegler-Natta or Phillips type is applied to the metal oxide particles.

11. The method according to at least one of claims 8 to 10, characterized in that a catalyst alkyl and / or olefin-functionalized metal oxide particles are added in sufficient quantity and this mixture is used for the polymerization 0.

12. Use of a polymer-based material according to at least one of claims 1 to 7 or a 5 polymer-based material produced by a method according to at least one of claims 8 to 11 for the production of sliding pairs, in particular ball bearings, roller bearings, sliding bearings, link chains, gear wheels in the technical field or Joint implants in the medical-technical area.

13. sliding pair in which the sliding partners consist of metallic, polymeric and / or ceramic materials, characterized in that at least one of the sliding partners is essentially made of a polymer-based material according to at least one of claims 1 to 7 or a polymer-based material produced by a method Q according to at least one of claims 8 to 11.

14. Artificial joint of a prosthesis in which the joint partners consist of metallic, polymeric and / or ceramic materials, characterized in that at least one of the fifth

Joint partner essentially from a polymer-based Material according to at least one of claims 1 to 7 or a polymer-based material produced by a method according to at least one of claims 8 to 11.