Binuclear catalyst and process for preparation of termoelastoplastic polyolefins
Field of the invention
The present invention relates to a new catalyst combination and a process for preparing physically crosslinked recyclable thermoplastic polyolefins of simplified processability. In particular the present invention relates to a new catalyst combination and a process for preparing of super high molecular weight isotactic polymers and copolymers of monomodal Gauss like molecular weight distribution with both linear and cyclic olefinically unsaturated compounds as monomer having isotacticity being within the range of from 15 to 70% of [mmmm] pentad concentration, weight average molecular weight within the range from 300,000 to 4,000,000 gms/mol, polydispersity within the range from 1.4 to 8.5 and statistic distribution of stereoscopic errors along the polymer chain.
Scope of the invention
Thermoplastic polyolefins have been of priority interest worldwide as plastic materials for manufacturing numerous articles for several decades. The stereoregular isotactic polyolefins, is of the particular interest in the industry due to this type of stereoregular polyolefins has the best mechanical properties compared to sindiotactic and atactic isomers.
The possibility to vary mechanical properties of different isotactic polyolefins in very broad ranges by plasticizing, blending, co polymerization and etc. allows filling almost all niches of applications in consumer products. Only one niche remains uncovered. This is the area of thermoplastic elastomers. Till the most resent study, there were no thermoplastic elastomers based on polyolefins available.
Three general types of elastomers are widely used in the industry nowadays.
First one is based on chemically crosslinked rubbery polymers. These polymers have the best performance, but require special methods for processing, can't be processed via methods conventional for thermoplastic polymers and, most important, all of the chemically crosslinked polymers can be processed into the article only once. An articles made from such polymers can't be reprocessed and recycling became problematic.
Second type is plasticized PVC. It is easy to process via conventional methods and it is subjected to multiple processing, but PVC known to be very toxic on decomposition and combustion and also it gradually releases plasticizer. The toxicity issue serves as reasons to avoid application of PVC in consumer products.
Third type is EPDM like copolymers. It is much easy to process these polymers compared to processing of cross-linked rubbery polymers, but anyway it is the copolymers and it can't be reprocessed. Recycling remains big issue.
Polyolefins like polyethylene, polypropylene and copolymers found numerous applications in industry. In particular the isotactic polypropylene found numerous applications in consumer products, household, packaging, motor care industry etc. due to it is the low cost thermoplastic, material having relatively good mechanical properties. Also it is very important that it is recyclable polymer, which can be re-processed for several times. However conventional isotactic polypropylene is not the elastomer. It is the polymer of highly crystalline nature and, therefore, relatively hard with little or no impact resistance and it is suitable only for application fields in which those characteristics are desirable.
Various attempts have been made, aiming to improve elasticity of polypropylene based material by controlling the crystallinity. Both isotactic and sindiotactic polypropylenes are highly crystalline polymers. Sindiotactic polypropylene is brittle polymer of high Tg and Tm close to decomposition temperature. It didn't find an application in the industry due to rapid decomposition on processing. In opposite the atactic polypropylene is completely amorphous liquid polymer. However the attempt to control crystallinity and improve elasticity by simply blending of crystalline types of polypropylene with the amorphous atactic one is fail. These polymers are completely immiscible and phase separation in the blend results fail in mechanical properties.
Most recently, it has been made attempt to decrease crystallinity of polypropylene by control of tacticity of said polymer during process of polymerization.
Background Art
European Patent Publication EP 0 707 016 Al specifies a catalyst composition and a process for preparing polyolefins. The catalysts specified in European Patent Publication EP 0 707 016 Al are the substances, made up of a metallocene compound having an indene ring and a fluorene ring which are bridged via C, Si or Ge atoms of general formula described hereinafter.
It is essential that, in the indene ring system at least the moiety denoted with R4 not to be the hydrogen. When that moiety R4 is hydrogen, the effects, such as specified in the aforementioned European Patent Publication will not be attained (P 6, from L 57 up to P 7, L 3). The polymers specified in European Patent Publication EP 0 707 016 A l have been prepared with these metallocene type catalyst. The polypropylene also can be prepared with those metallocene catalysts, however, the polypropylene described in the European Patent Publication EP 0 707 016 Al is not the elastic one. The characteristics of all polyolefins described in the European Patent Publication EP 0 707 016 Al are unsatisfactory in regard to their elastic behavior as it can be drawn from the examples and the graphs mentioned in the patent.
The most close to the object of present invention is that described in Patent Publication EP 1 178 057 A2 and WO 02 46247 A2 which specifies a catalyst combination for preparing linear isotactic polymers where said catalyst combination containing a metal complex of general formula described hereinafter:
wherein the substituents have the following significations:
R1 - R7 equal linear or branched Ci to Cι0 alkyl, 5- to 7-linked cycloalkyl which, in its turn, can carry one or several Ci to C6 alkyl residues as substituent, C6 to Cι8 aryl or arylalkyl or alkylaryl, in which case R'/R2, R3/ R4, R6/R7 can be partially or simultaneously integrated into 5- to 7-linked cycloalkyl or aryl rings fused thereto;
E equal 1.2-ethyl, 1.3-propyl, 1.4-butyl, or - carbon, silicon, germanium optionally with
R9, RIO equal CI to C8 alkyl, 4- to 7-linked cycloalkyl, aryl, in which case R9, RIO can, jointly with E, form a 4- to 7-linked cycloalkyl or aryl;
E2 = C2, therewith, signifies oxygen or sulphur and n is 1 or 2;
R1 ' equal Ci to C alkyl, aryl, Ci to C8 oxyalkyl, , C, to C8 trialkylsiloxy; M equal titanium, zirconium, hafnium, vanadium, niobium, tantalum; X equal halogen orCi to C8 alkyl, aryl, benzyl;
The metallocene catalysts according to European Patent publications EP 1 178 057 A2 and WO 02 46247 A2 are accompanied with methylalumoxan activator (MAO).
The polymers prepared according to the EP 1 178 057 A2 and WO 02 46247 A2 are linear, thermoplastic, elastic polymers made from an olefinically unsaturated compound with an isotactic arrangement of the monomer units and a statistic distribution of isolated stereoscopic errors along the individual chains. The average molecular weight Mw of the polymers is in the range of from 100,000 to 800,000 gms/mol. The glass transition temperature is in the range from -50 to +30. The most essential for the polymer prepared according to the EPA is the following: • Stereoscopic errors are isolated and obligatory has neighboring isotactic units. • Catalyst is of metallocene type providing insertion mechanism of polymerization • Narrow molecular mass distribution independently from the average molecular weight of the polymer obtained resulting from type of catalyst and mechanism of polymerization. • Catalyst is very much sensitive to residual amount of the moisture in the polymerization medium.
Because of these inherent disadvantages of the process according to the invention described in the EPA the polymer obtained according to the said invention has shortcomings mentioned below. The low and middle molecular weight polymer of narrow molecular weight distribution (n<2.5) and with Mw up to 500,000 gms/mol can be processed from the melt via conventional methods like blow molding, ram-extrusion, compression molding etc. and has acceptable melt viscosity characterized with acceptable value of zero share melt viscosity T|o. However such isotactic polyolefins, if contains low concentration of stereo errors, are stil brittle materials due to too high rystallinity. Increasing the concentration of stereo errors makes it more amorphous and elastic, but at the same time it become sticky and can't be used. Stickiness disappears with further growth of average molecular weight, however high molecular weight polymer can't be processed from the melt due to very high viscosity of the melt. Viscosity of the melt increases with the growth of molecular weight of polymer. Till the molecular weight is lower them a critical value Mw<Mc the melt viscosity grow linearly with growth of weight average molecular weight (ηo~kMw), however for polymers possessing higher molecular weight (Mw>Mc) the dependence become rather strong (ηo∞Mw ' ). The difference is related to the ability of long chains to entangle which imposes melt a restriction to ease flow. The critical value of weight average molecular weight for elastic polypropylene is close to 350,000 gms/mol while polymer is stil sticky. Further growth of Mw up to values of Mw>500,000 gms/mol results non-sticky polymer, however entangling of macromolecules in the melt results too high viscosity disabling processing. Actually it is a dilemma: Low Mw - sticky polymer, high Mw - difficult to process.
This is not the case for polymers with broad molecular weight distribution (n>3) or polymer blends comprising admixture of low Mw polymer or of plasticised polymers where relatively small molecules of low Mw fractions serve as a lubricants preventing entangling of large macromolecules. However narrow molecular weight polyolefins obtained using metallocene catalysts according to the EP 1 178 057 A2 and WO 02 46247 A2 are almost immiscible with other types of polyolefins and even with the same type of polyolefin of low Mw. It makes impossible to provide high Mw polyolefins with melt processability via blending.
Disclosure of the invention
Departing from all these facts described in the art the object of the present invention is the novel catalyst combination of non-metallocene type, the process to make polymers from olefinically
unsaturated compounds using herein catalyst combination, and polyolefins obtained including but not limited the physically crosslinked polyolefins demonstrating thermoplastic and thermoplastic- elastic properties. The polymers by present invention may be obtained in the sticky form, but also not sticky. The polymers are easy processable from the melt and, thus, being applicable for many application fields. That object is in regard of the catalyst combination, solved by the characterizing features of Claim 1 ; in regards to the process for preparing the polymers, the characterizing features of Claim 4 solve it. First aspect of the present invention First aspect of the present invention is the novel catalyst combination containing a transition metal compound and an activator.
Herein after the transition metal compound is organometalic compound, comprising the phenoxyimine type organic ligand and a metal atom one from those of Fourth Auxiliary Group of the Periodic System Table IVB able to form formally positively charged polymerization initiation site located on the metal atom following interaction with an activator. Titanium, zirconium and hafnium are preferably suitable as the metal atoms.
Initially the transition metal compound according to the invention contains either halogen or a Ci - C3 alkyl aryl or benzyl residues bonded to metal atom at the position X, however there are eliminated by an activator resulting positively charged polymerization site of the catalyst at the initial stage of the polymerization process described hereinafter.
The transition metal containing organometalic compound hereinafter called a transition metal compound may be represented by the Formula III:
wherein the substituents have the following significations:
M - metal of the Fourth Auxiliary Group of the Periodic System, preferably titanium, zirconium, hafnium, vanadium, niobium or tantalum;
X - halogen or a C\ - C3 liner or branched alkyl, aryl or benzyl X2 - halogen or a Ci - C liner or branched alkyl, aryl or benzyl R' - H or halogen or a linear or branched Ci - C alkyl, R2 - H or halogen or a linear or branched Ci - C alkyl, R3 - H or halogen or a linear or branched C\ - C4 alkyl, R4 - H or halogen or a linear or branched Ci - C4 alkyl, and an activator.
As defined in Claim 1 of present invention, it certainly is furthermore provided in accordance with the invention, to additionally use at least one activator, apart from the transition metal compound specified above. European Printed Publication 1 178 057 A2 and WO 02 46247 A2 have also specified such activators and the invention, herewith, also encompasses all the activators that are known in the state-of-the-art as a co-catalysts for metallocene compounds, however in the present invention these activators are reapplied to the novel family of catalysts of phenoxyimine type specified above as the transition metal compound. At least one compound of genera Formulas II to VI is, however used with special preference. Accordingly, the activator may be an open-chain or cyclic alumoxane compound of general Formula IV or V, such as is reflected hereinafter:
R7 R7 (IV) (Al-O-)„ (V) (Al-O-)„
wherein R7 is a Ci - C4 alkyl group and n is a number between 5 and 30.
In case of the catalyst combination according to the invention, also the above-specified compounds of general Formulas IV and V can, alone or in combination with the subsequent activators such as those reflected by general Formulas IV to VI, be used. B(C6F5)3 (VI) R8 3C[B(C6F5)4] (VII)
[R8 3NH][B(C6F5)4] (VIII) In general, Formulas VI to VIII, R , signifies a Ci - C alkyl group or an aryl group. It has, therewith, proven to be especially favorable when the transition metal compound according to general Formula III and the activator according to general Formulas IV to VIII are employed in such quantities that the atomic ratio between aluminium from the alumoxane or boron from the cationic
activator and the transition metal from the transition metal compound specified below is within the range of from 1 : 1 to 106: 1. Second aspect of the present invention
The invention, furthermore, provides the process for preparing linear, thermoplastic-elastic polymers from olefinically unsaturated compounds with an isotactic arrangement of the monomer unit and a statistic distribution of isolated stereoscopic errors along the individual chains, tacticity varying within the range of between 15 and 70 % [mmmm] pentad concentration. A regular sequence of isotactic and atactic blocks, therewith, is excluded. The process according to the invention is specifically characterized in that a specially selected catalyst combination is used as described before.
Pressures of from 1 to 100 bars, preferably of from 3 to 20 bars and in particular of from 5 to 15 bars, have proven to be suitable reaction parameters for preparing the linear thermoplastic, elastic olefin polymers. Favorable temperatures are within the range of from -50 °C to 200 °C, of preference at from 100 to 150 °C and of high preference at from 20 to 50 °C. The polymerization reactions can be carried out in the gas phase, in suspension and in supercritical monomers and especially in solvents inert under polymerization conditions. In particular the polymerization in the liquid propylene as the solvent and slurry process has proven to be the clearly superior thing for the present preparation process. The inert solvents are particularly suitable for such process. Inert solvents herein are such solvents that do not contain any reactive groups in the molecule, i.e. aromatic solvents like benzene, toluene, xylene, ethylbenzene or alkanes such as e.g. propane, n-butane; i-butane. pentane, hexane, heptane or mixtures thereof.
Third aspect of the present invention
The invention, furthermore, provides the linear, thermoplastic, elastic polymers from an olefinically unsaturated compound with an isotactic arrangement of the monomer units and a statistic distribution of isolated stereoscopic errors along the individual chains and a mean molecular weight
Mw of the polymers within the range of from 300,000 to 4,000,000 gms/mol and a TG of from -50 to +30.
With the polymer prepared according to the invention, it is essential that the stereoscopic errors be situated along the main backbone of the polymeric chain.
Apart from the above-mentioned stereoscopic errors distribution along the polymeric chain the linear, isotactic polymers according to the present invention have a molecular weight within the
range of from 300,000 to 4,000,000, of preference from 700,000 to 2,500,000 and of special preference within the range of from 1,000,000 to 2,000,000 gms/mol.
The molecular weight distribution and polydispersity coefficient n=Mw/Mn (weight average molecular weight value/number average molecular weight) of the polymers according to the present invention are of the particular importance. The polydispersity coefficient generally amounts within the range from 1.4 to 8.5. The molecular weight distribution of the polymer according to the invention may be polymodal, however preferably it is the monomodal, Gauss like type. The relatively high polydispersity provides polymer with improved processability from the melt. Low molecular weight fractions serve as lubricant preventing entangling of big molecules and thus decreasing zero share viscosity of the melt and melt index.
In addition to all that, the polymers show a glass transition temperature Tg within the range of from -50 °C to +30 °C, of special preference a Tg of from -20 °C to +10 °C.
The linear, isotactic polymers prepared according to the invention present a structure of one or several C2 - C2o olefins. In this case, the olefin is preferred to be a C3 - C o - Alk-1 -ene. Examples of such C3 - C2o -Alk-1 -enes are: propene, 1-butene, 2-butene, 1-pentene, 1-hexene, 1 -octene, 1- nonene, 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene, 1-eicosene.
Apart from the already mentioned olefins, also C5 - C2o cycloolefins are of the especially suitable kind. Examples thereof are cyclopentene, cyclohexene, norbornadiene and its derivatives. In case of the linear, isotactic polymers, polypropylene is especially preferred. Further suitable polymers are copolymers from propylene and a C - C o olefin or a cycloolefin. It is also possible to prepare terpolymers which show the characteristics defined in Claim 1 of present invention when they present a structure of propylene, a C2 - C o olefin and a cycloolefin.
The polymers prepared according to the invention has a distinct elastic properties due to it's specific morphology comprises microcrystalline domains surrounded with areas of elastic amorphous polymer. Due to its morphology, it can be classified as Physically Crosslinked polymer. Crystals serve as the cross linkages or lattice points of the net type structure. Amorphous areas provide to polymer with elasticity while crystalline domains prevent forced viscous flow of the polymer providing good reset. The crystalline phase possess to melting on processing resulting conventional melt of none-crosslincked polymer. The process is reversible and after crystallization on processing the polymer restores initial morphology and mechanical properties. The polymers prepared according to the invention show a distinct elastic behavior in a tensile-strength test, measured with a "Standard Universal Testing Machine Instron-1 122". A melting temperature, measured by means of the "Differential Scanning Calorimetry" (DSC) method within the range of from -50 °C to 250 °C.
The polymer according to the invention clearly differ in regard of their elastic-thermoplastic behavior, from the state-of-the-art, i.e. from European Printed Publication 0 707 016 Al mentioned in the state of art. The polymers prepared according to the present invention are particularly suitable for the manufacture of articles of relatively good deformation resistance, such as e.g. sheathings for household appliances. Furthermore, it is worth mentioning that the polymers can be used in polymer mixtures for impact resistance modification. Due to their elastic characteristics, the polymers are especially suited for elastic sheets, cable insulation, filaments, flat materials including nonwoven materials, films, foams, coatings, molded bodies, gaskets.
The invention can be illustrated with the following examples Methods applied
The NMR spectra of the polymers were recorded at 1 10°C on a Bruker AC-200 instrument using
1 ,1,2,2-tetrachloroethane-Gk as the solvent. The concentration of polymer in the solution was 7.5% w/w.
The NMR spectra of ligands and catalysts were recorded at ambient temperature using a Bruker
AMX -400 instrument and chloroform - CDC13 as a solvent.
IR spectra were recorded using with a Magna-IR 750 spectrophotometer.
The molecular weight distribution, the weight average molecular weights Mw, the number average molecular weight Mn and polydispersity coefficient n=Mw/Mn of the polymers were measured by the gel permeation chromatography (GPC) method at 135°C with microstyragel as column material.
Measurements were made using Waters 150-C instrument equipped with a linear HT-μ-styragel column calibrated with both polypropylene and polystyrene standards and 1,2-dichiorobenzene as a solvent.
The glass transition temperature was determined by means of the "Differential Scanning
Calorimetry" (DSC) method.
Mechanical properties and elasticity were determined in a tensile-strength test, measured with a
Instron-1 122 machine.
The polymerization experiments were carried out in 250 ml stainless still reactor under the conditions described below.
X-ray powder diffraction analysis of PP samples was carried out on a DRON-2 diffractometer.
Preparation of catalyst
Preparation of 4,4'-bis(3,5-di-tert-butylsaIicylidene)- 2,2',3,3',5,5',6,6'-perfluorodipheny.e
50 ml the two neck flask was filled with 20 ml of toluene, 0,1990 g (0.85 mmol) of 3,5-di-tert- butylsalicylic aldehyde, 0,0017 g (0.01 mmol) of p-toluenesulfonic acid and 0,1503 g (0.43 mmol) of l ,r-perfluorodiphenile. The mixture was heated with reflux for 20 hours, then solution was cooled to ambient temperature, filtered and the solvent was removed in vacuum resulting deep yellow oil. The product was dissolved in 20 ml of mixture hexane-ethyl acetate (5:1) and purified by column chromatography using silica gel as absorbent and the mixture of hexane-ethyl acetate (5:1) as the eluent resulting 0,5305 g of yellow oil.
Yield 0,7228 mmol (82 %), 1H NMR: : δ 1,46 (d, 72H, tert-Bu), 7.05 (4H, aromatic H), 7.36 (4H, aromatic H), 8,84 (s, 2H, CH=N), 11.79 (s, 2H, OH). IR: v/cm"1: (C=N) 1690. Analysis found (%): C, 66,29; H, 5,70; N, 3,62. Calculated for C42H44N OF4 (%): C, 66,31; H, 5,83; N, 3,68.
Preparation of bis[4,4'-bis-(3,5-di-tert-butylsalicyIidene)perfluorodiphenile]titanium(IV) dichloride
50ml three-neck flask equipped with mechanical stirrer, argon inlet tube and dosing funnel was purged with dry argon and charged with solution containing 0,0800 g (0.10 mmol) of 4,4'-bis-(3,5- di-tert-butylsalicylidene)perfluorodiphenile dissolved in 10 ml of methylene chloride. The solution containing 0,0240 g (0.10 mmol) of TiCl2(O Pr)2 in 15 ml of methylene chloride was added dropwise with stirring. The mixture was agitated for 20 hours at ambient temperature; solid product was filtered out from reaction mixture, washed with methylene chloride and toluene and dried in vacuum at 60°C to remove residues of solvent with following purging with dry argon to give 0,0784 g of crystalline product.
Yield 0,0447 mmol (85%), IR, v/cm-1: (C=N) 1610; (Ti-O) 566, (Ti-N) 472, (Ti-Cl) 420, 397; Η NMR: δ 1,54 (d, 144H, t-Bu), 7,05 (m, 8H, aromatic H), 7,36 (m, 8H, aromatic H), 8,93 (s, 4H, CH=N). Analysis found (%):C, 57.40; H, 4.86; N, 3.03; Ti, 5.42; CI, 7.98. Calculated for Ti2C84H12N4O4Fι6Cl4 (%):C, 57.48; H, 4.82; N, 3.19; Ti, 5.45; CI, 8.08.
Polymerization Polymerization of ethylene Example N°l The 250 ml stainless steel reactor was evacuated with following flushing with dry argon for several times for replacement of air and moisture then it was filled with 100 ml of dry toluene. 7.6 mmol of MAO in form of 10% solution in toluene was injected into reactor and argon was replaced with ethylene to maintain pressure at 1 1 atm. In 5-10 min on reaching the saturation of ethylene dissolution at 1 1 atm and 30oC the polymerization was initiated by injection of 0.5 ml of solution containing 3.8 μmol maintaining molar ratio AIMAO/ J molar is equal 2000 mol/mol. Polymerization was conducted for 10 min then reactor was depressurized, residual ethylene was removed by purging with argon, then 20 ml of ethanol containing of 2% wt of HC1 was added for neutralization of catalyst, the solvent was evaporated in vacuum. The polymer was washed with ethanol/water mixture and dried to in vacuum at 60 °C resulting 12.3 g of polyethylene with Tm=142oC according to DSC. Example N°2 The 250 ml stainless steel reactor was evacuated with following flushing with dry argon for several times for replacement of air and moisture then it was filled with 100 ml of dry toluene. 1.9 mmol of MAO in form of 10% solution in toluene was injected into reactor and argon was replaced with ethylene to maintain pressure at 1 1 atm. In 5-10 min on reaching the saturation of ethylene dissolution at 11 atm and 30oC the polymerization was initiated by injection of 0.5 ml of solution containing 3.8 μmol maintaining molar ratio AIMAO/TI molar is equal 500 mol/mol. Polymerization was conducted for 10 min then reactor was depressurized, residual ethylene was removed by purging with argon, then 20 ml of ethanol containing of 2% wt of HC1 was added for neutralization of catalyst, the solvent was evaporated in vacuum. The polymer was washed with ethanol/water mixture. The residues of the solvent were removed in vacuum at 60 °C resulting 13.4 g of polyethylene with Tm=142oC according to DSC. Example N°3 The 250 ml stainless steel reactor was evacuated with following flushing with dry argon for several times for replacement of air and moisture then it was filled with 100 ml of dry heptane. 1.9 mmol of MAO in form of 10% solution in toluene was injected into reactor and argon was replaced with ethylene to maintain pressure at 1 1 atm. In 5-10 min on reaching the saturation of ethylene dissolution at 1 1 atm and 30oC the polymerization was initiated by injection of 0.5 ml of solution
containing 3.8 μmol maintaining molar ratio AlMAθ/Ti molar is equal 500 mol/mol. Polymerization was conducted for 10 min then reactor was depressurized, residual ethylene was removed by purging with argon, then 20 ml of ethanol containing of 2% wt of HC1 was added to the suspension with intensive stirring for neutralization of catalyst, the solvent mixture was evaporated in vacuum. The polymer was washed with ethanol/water mixture. The residues of the solvent were removed in vacuum at 60 °C resulting 8.3 g of polyethylene with Tm=133oC according to DSC.
Polymerization of propylene
Example JV°4 Propylene polymerization has been carried out in the medium of liquid propylene in stainless steel reactor (200 ml) under rigorous stirring of reaction medium. The 200 ml stainless steel reactor equipped with mechanical stirrer was heated to 70°C for 1.5 hours with continues pumping out the residues of moisture and air then it was cooled to ambient temperature and purged with gaseous propylene with following filling with 50 ml of liquid propylene. The reactor was heated to 50°C maintaining pressure of 40 atm and 1 ,35 ml of 10% solution of MAO (10.35 mmol) in toluene was injected. Then glass ampoule containing 3,952 mg (2.2 μmol) of bis[4,4'-bis-(3,5-di-tert- butylsalicyIidene)perfluorodipheniIe]titanium(IV) dichloride was injected into reactor with following braking with special plunger. In 1 .5 hour the polymerization was stopped by venting of propylene following injection of ethanol into the reaction medium giving 5.0 g of polypropylene. JC NMR (mmmm 8.9 %, mmmr 12.3 %, rmmr 4.7 %, mmrr I 1.2 %, mmrm+ rmmr 25.6 %, rmrm 10.5 %, rrrr 3.7 %, mrrr 15.9, mrrm 7.1 %), Mw is 952000 g/mol, Mw/Mn is 10.1 . Mechanical properties: elasticity modulus 2.9 MPa, rupture stress >0.6 MPa, elongation at rupture > 1800 %. recovery set after 300 % elongation 6.4 % (Fig. 2, 4).
Example N°5 Propylene polymerization has been carried out in the medium of liquid propylene in stainless steel reactor (200 ml) under rigorous stirring of reaction medium. The 200 ml stainless steel reactor equipped with mechanical stirrer was heated to 70°C for 1.5 hours with continues pumping out the residues of moisture and air then it was cooled to ambient temperature and purged with gaseous propylene with following filling with 50 ml of liquid propylene. The reactor was heated to 50°C maintaining pressure of 40 atm and 1 ,35 ml of 10% solution of MAO (10.35 mmol) (AlMAθ/Ti=300
mol/mol) was introduced into reaction medium, in toluene was injected. Then glass ampoule containing 4,128 mg (2.3 μmol) of bis[4,4'-bis-(3,5-di-tert-butylsaIicylidene) perfluorodiphenile]titanium(IV) dichloride was injected into reactor with following braking with special plunger. In 1.5 hour the polymerization was stopped by venting of propylene following injection of ethanol into the reaction medium giving 6.9 g of polypropylene Microstructure of PP sample is close to that of atactic polypropylene.
I3C NMR (mmmm 8.9 %, mmmr 12.3 %, rmmr 4.7 %, mmrr 1 1.2 %, mmrm+ rmmr 25.6 %, rmrm
10.5 %, rrrr 3.7 %, mrrr 15.9, mrrm 7.1 %), Mw is 9872000 g/mol, Mw/Mn is 8.8. Physico mechanical properties of PP sample: elasticity modulus 4.3 MPa, rupture stress >0.8 MPa, elongation at rupture > 1800 %, recovery set after 300 % elongation 6.7 % (Fig.3).
The present invention also can be illustrated hereinafter in more detail with following figures.
En ample A ample ->
Fig.l . Tensile strength measurements on two polymers prepared according to the invention (Example 4 and Example 5) in comparison with polymers have been described in the prior art EP 0 707 016 A1.