DE3148229A1 - Process for the preparation of polyolefin waxes - Google Patents

Abstract

Pale-coloured polyolefin waxes, in particular polypropylene waxes, having a high degree of crystallinity and melt viscosities of from 50 to 100,000 mPas/170 DEG C can be obtained by solution polymerisation of alpha -olefins in the presence of a catalyst system composed of a component A, which is a product of the reaction of titanium tetrahalide, magnesium alkoxide and a specific electron donor, an organoaluminium compound as component B, and a stereoregulator as component C.

Description

Process for the production of polyolefin waxes

The invention relates to a process for the polymerization of 1-olefins, especially propylene, to polyolefin waxes with unusually high crystallinity, the catalyst used for this purpose as well as those produced by this process Waxes.

From DE-PS 23 29 641 it is known that the polymerization of propylene in the presence of one obtained by reacting a titanium compound with a magnesium compound Catalyst at relatively high temperatures to waxy polymers with comparatively high melt viscosity. The crystallinity of these waxes is in the lower to medium range and can be due to the nature of the activation of the catalyst the organoaluminum compound used can be influenced within certain limits, at most, however, only medium degrees of crystallinity are achieved.

Highly crystalline, hard polypropylene and polybutylene waxes with low Melt viscosities have not yet been obtained by polymerization, but only through thermal degradation of high-polymer, plastic-like polypropylenes [e.g. 8. US-PSS 28 35 659 and 35 62 788 and also Jour. of appl. polymer Science, Vol. 11 (1967) site 1280].

Such waxes usually show as a result of the Thermal and oxidative damage caused by high degradation temperatures is one more or less strong yellowing and have unsatisfactory thermal stabilities. In addition, their production is complex, since it is initially a high polymer and then in a second step in complicated apparatus must be broken down again with losses and formation of undesired by-products.

It has been found that highly crystalline ones can also be obtained in a direct build-up reaction hard polypropylene waxes and also waxy ones Polymers the base of other α-olefins, which are also crystalline, can get if a special catalyst system is used for the polymerization.

The invention therefore provides a process for the production of Polyolefin waxes by homo- or copolymerization of olefins in general Formula R-CH = CH2 in which R is a hydrocarbon radical with 1 to 38 carbon atoms means, in an inert solvent as the reaction medium, not at temperatures below 95 T, in the presence of one consisting of components A, 8 and C. Catalyst system, in which the component A by reacting a tetravalent Titanium compound, a magnesium compound and an electron donor Reaction product, the component 8 an organoaluminum compound and the component C is a stereo regulator, which is characterized in that in component A as a tetravalent titanium compound is a titanium tetrahalide, as a magnesium compound a magnesium alcoholate and, as an electron donor, a compound from the group the alcohols, ethers, amines or carboxylic acids and their derivatives serves, wobsi the Mg compound: titanium compound molar ratio 1 sec is 0.2 to 1: 5 and the electron donor in an amount of 0.01 to 10 mol, based on the titanium content, component B is an organaluminum compound of the formula R AlCl n (3-n) in which R is a hydrocarbon radical with 1 to 30 carbon atoms and n = 1, 2 or 3, and as a stereo regulator C is a compound the group of carboxylic acid esters, phosphoric acid amides, ethers or thioethers are used is the molar ratio of component B (based on A1) to component A (based on on Ti) at 1: 1 to 30: 1 and the molar ratio of component C to component A (based on Ti) is 0.1 t 1 to 10: 1 and the polymerization temperature 95 to 150 s.

It was surprising and not to be expected that it would be possible Polyolefin waxes with a particularly high degree of crystallinity according to another than the mining method. In the synthesis of propylene polymers for the plastics sector namely, the crystallinity decreases with increasing polymerization temperature in the Rule off. Not least because of this, temperatures are usually considerable here worked under 100 s.

That it succeeds when using the catalyst system according to the invention would be among those used in the manufacture of low melt viscosity polyolefin waxes necessary polymerization conditions, especially at high reaction temperatures, Obtaining products with a high degree of crystallinity was by no means for this reason predictable.

The starting monomers used are 1-olefins with 3 to 40, preferably 3 to 18 and especially 3 to 5 carbon atoms. Is mentioned as being particularly preferred Propylene. There are also suitable z. B.

3-methylpentene, 1-outene, 1-pentene, 1-octedecene, longer-chain, after α-olefins accessible to the Ziegler synthesis, as well as mixtures of the olefins mentioned with one another or mixtures of these monomers and ethylene in an amount from. up to approx.

2 vol.

The preparation of the catalyst is carried out in such a way that one first the catalyst component A is prepared by using a magnesium compound, preferably a magnesium alcoholate, with a tetravalent titanium compound, preferably one Titanium tetrahalide, particularly preferably titanium tetrachloride, in an inert solvent implements. Compounds of the general formula Mg (OR) 2 are used as magnesium alcoholate used, in which R stands for identical or different hydrocarbon radicals, preferably straight-chain or branched alkyl radicals with 1 to 10, preferred 1 to 4 carbon atoms. Examples are Mg (OCH3) 2, Mg (OC2H5) 2, Mg (OC3H7) 2, Mg (ûC4Hg) 2 called. However, magnesium alcoholates of the general formula can also be used MgX (OR) can be used in which X is halogen, (S04) 1/2 "carboxylate or -OH and R has the meaning given above.

The tetravalent titanium compound is associated with the magnesium compound Temperatures between 0 and 200, preferably between 20 and 120 s brought to reaction. An inert diluent or suspending agent, for example, serves as the reaction medium a hydrocarbon. Aliphatic or cycloaliphatic hydrocarbons are suitable such as 8. Hexane, heptane, cyclohexane, as well as aromatic hydrocarbons such as toluene etc. It is advantageous to present the magnesium component as a suspension and to add it Stir in the titanium compound. Magnesium and titanium compounds are expedient and preferably used in a molar ratio of 1: 0.2 to 1: 5, but molar ratios are also used possible outside this range. The reaction times are generally between lund 10 hours.

The catalyst precursor thus obtained is obtained as a solid.

It is made by repeated washing with inert hydrocarbons freed from soluble components and then reacted with the electron donor. Suitable electron donors are alcohols such as methanol, propanol, benzyl alcohol, Phenol, preferably ether, and of these in turn preferably aliphatic and aromatic, but especially aliphatic such as diethyl ether, di-n-propyl ether, Oi-n-butyl ether, di-n-amyl ether, di-i-amyl ether, amines such as triethylamine, tripropylamine etc. and aliphatic and aromatic carboxylic acids and their derivatives such as esters, Halides, anhydrides and amides, for example ethyl acetate, ethyl benzoate, Benzoyl chloride, benzoic anhydride and benzamide. For implementation with the electron donor, in amounts of 0.01 to 10, preferably 0.1 to 5 mol, based on the titanium content of the catalyst precursor is used, one also works in an inert one Suspending agent at temperatures between 0 and 200, preferred between 20 and 120 cm and allows 0.05 to 10 hours, preferably 0.5 to 5 hours react.

The resulting solid is then washed off repeatedly freed from IB61ichen fractions with an inert hydrocarbon.

As an organoaluminum component, this is the catalyst component 8, compounds of the formula RnAlCl (3 n) are used in which R is alkyl radicals with 1 to 30, are preferably 2 to 12 carbon atoms and n = 1, 2 or 3. The atomic one The ratio of C1: Al is accordingly between 2: 1 and 0: 1, preferably a ratio between 1 s 1 and 0.25: 1 is set, which is achieved by mixing organoaluminum compounds with different chlorine content, for example Triethylaluminum and diethylaluminum chloride takes place.

As stereo regulators, which represent the catalyst component C, are compounds from the group of carboxylic acid esters, phosphoric acid amides, ethers and thioethers are used. Preferred are the esters of aromatic carboxylic acids such as for example ethyl benzoate, methyl benzoate, ethyl p-toluate, methyl p-toluate, ethyl anisate and methyl anisate by themselves alone or in any mixture with one another.

This is the preferred way of carrying out the polymerization before that you first prepare the catalyst mixture by adding the component C with component 8 by mixing in the presence of an inert hydrocarbon brings to reaction and then adds component A to this mixture. The quantities are to be chosen so that the molar ratio of component 8 (based on aluminum) to component A (based on titanium) between 1: 1 and 30: 1, preferably between 2: 1 and 20: 1 and the molar ratio of component C to component A (based on on titanium) is 0.1: 1 to 10: 1, preferably 0.5: 1 to 3: 1.

The polymerization itself then becomes continuous or discontinuous in solution at temperatures between 95 and 150, preferably 100 and 120 and in particular 100 and 110 S in the pressure range below 20 bar, preferably between 2 and 10 bar, carried out. As in the case of catalyst production, inert solvents are used as solvents Hydrocarbons. It is also possible to use liquid, however, to polymerize solid inert hydrocarbons at room temperature.

The amount of catalyst is such that component A is in concentrations (based on titanium) between 0.1 and 5 milligram atoms, preferably between 0.2 and 2 milligram atoms per liter of reaction medium is present.

The achievable degree of polymerization can be determined via the temperature, affect the pressure and composition of the catalyst.

It can also be used in the well-known catfish by adding hydrogen gas be managed. The products have molecular weights between approx. 500 and 10,000.

After the end of the polymerization, the solvent is separated off preferably - optionally after previous decomposition of the catalyst with polar Decomposing agents, e.g. 8. Water, followed by filtration - by distillation.

The polyolefin waxes produced by the process according to the invention are tough-hard, colorless, non-sticky, thermally stable, easily grindable products with high degree of crystallinity (it results from the isotactic component, which is generally is over 75%) and melt viscosities between about 50 and 100,000 mPas, measured at 170 t, which can be used, for example, as base materials for pigment preparations, for the abrasion protection of printing inks, for matting varnish, as an aid when processing plastics, for example as a lubricant or release agent, as well as suitable as a melting point raiser.

+) Determined by IR spectroscopy The following examples serve to further explain the invention. The degree of crystallinity of the respective Polymers can be determined from the values determined for the .meizwärme and the Derive flow hardness in that these key figures are higher, the higher the crystallinity ingredient is. In the case of the waxes built up exclusively from propylene, the degree of crystallinity became additionally determined by IR spectroscopy.

Example 1 a) Preparation of a catalyst component A 114.4 g of magnesium ethylate were suspended in 1000 ml of a diesel oil fraction (boiling range 140 to 160). 380 g of titanium tetrachloride were added dropwise with stirring at 85 s over the course of 4 h. The suspension was then for a further 30 min.

stirred at 85 s. The precipitate was decented and repeated Again stirring, washed with diesel oil until the diesel oil is above the solid was free of titanium.

The titanium content of the suspension was determined colorimetrically with hydrogen peroxide certainly. 5% of the titanium used was fixed on the solid.

The suspension was then mixed with 31.7 g of diisoamyl ether as an electron donor added and stirred for 1 h at 100 tons. The solid was again washed with Soluble titanium compounds are removed from diesel oil. It then still contained 4% of the original titanium used as titanium tetrachloride.

b) Polymerization of propylene in a 40 l kettle with impeller stirrer 15 l of a diesel oil fraction (boiling range 140 to 160 t) are presented. To Heating to 100 cm was then hydrogenated up to an internal pressure of 3 bar Propylene metered in up to an internal pressure of 5 bar. At 100 s, 0.5 1 became one Catalyst mixture pumped in, - what results from 160 mmol triisobutylaluminum, 160 mmol diethylaluminum chloride, 40 mmol benzoic acid ethyl ester (catalyst components 8 and C), 86 ml (corresponding to 20 mgat of fixed titanium) of the above catalyst component A and 1.5 1 diesel oil.

By continuously adding 3.2 kg of propylene per hour and 3 liters of hydrogen and occasional feed of catalyst mixture became the Pressure kept at 5 bar. The polymerization temperature was between 100 and 110 s set.

After 1.5 hours there was a total of 980 ml of the catalyst mixture corresponding to 11.2 mgat Ti consumed. The reaction was stopped by adding 15 ml Water interrupted, the polymer solution filtered and the solvent in vacuo ebdistilled. 4.8 kg of polypropylene wax remained, corresponding to a contact yield of 429 g wax per mgat titanium. The product was colorless and glass-like hard.

Key figures: Melt viscosity at 170 t: 1200 mPss heat of fusion: 63 Jg isotactic fraction by IR spectroscopy: 85% flow hardness:> 1000 bar dropping point: 158 to 160 s (DGF M III, 3) Comparative experiment to Example 1 by Reacting magnesium ethylate and titanium tetrachloride was a catalyst according to DE-PS 23 29 641, Example 1a, produced.

The polymerization of propylene using this catalyst and the conditions mentioned in Example 6 of DE-PS 23 29 641 led to a Polypropylene wax, which has a lower crystallinity than that according to the example 1 obtained, whereby the influence of the electron donor increases the crystallinity is proven.

Key figures: melt viscosity at 170: 25,000 mPas heat of fusion: 30 Jg isotactic fraction by IR spectroscopy: 67% flow hardness: approx. 1000 bar Example 2 Analogously to Example 1, 15 l of diesel oil were placed in the polymerization kettle. To Heating to 100 s was hydrogen gas up to an internal pressure of 2.5 bar and then propylene is injected up to a total pressure of 5 bar. Pumped at 100 s then 0.4 l of a catalyst mixture consisting of 160 mmol of triethylaluminum, 160 mmol diethylaluminum chloride, 40 mmol benzoic acid ethyl ester and 86 ml (corresponding to 20 mmol of fixed titanium) of contact component A from Example 1, suspended in 1.5 1 diesel oil, too.

By constantly replenishing propylene / hydrogen uie in the example 1 and occasional addition of catalyst mixture, the pressure was kept at 5 bar. The polymerization temperature was 100 to 110 ° C. After 1.5 hours, 11 (10 ml of the contact mixture corresponding to 13 mgat Ti consumed. After contact decomposition and working up as in Example 1, 5.0 kg of polypropylene wax were obtained had the following key figures: Melt viscosity at 170: 3800 mPas heat of heat: 60 Jg 1 isotactic fraction by IR spectroscopy: 82% flow hardness: > 1000 bar dropping point: 158 to 160 Cc Example 3 a) Production of a catalyst component A The reaction product of magnesium ethylate and titanium tetrachloride was analogous Example 1 prepared using the amounts specified there. On that of soluble The solid content of the suspension freed from titanium compounds was 4.5% of the amount used Titanium fixed.

The suspension was then with 33.2 g of di-n-hexyl ether as Electron donor was added and the mixture was stirred at 100 ° C. for 1 hour.

The solid, washed free of titanium, then still contained 4% of the original titanium used as titanium tetrachloride.

b) Polymerization of propylene A 50-1 kettle was used, as in the example 1, prepared for polymerization. At 100 Cc, 0.47 l of a catalyst mixture consisting of 160 mmol triethylaluminum, 160 mmol diethylaluminum chloride, 40 mmol of ethyl benzoate and 81 ml (corresponding to 20 mgat fixed titanium) of the above Pumped in contact suspension in 1.5 l of diesel oil.

By continuously replenishing propylene / hydrogen such as in Example 1 and occasional addition of catalyst mixture, the pressure was at 5 bar held. The polymerization temperature was 100 to 110 tons. After 1 hour if the reaction was interrupted by adding water, the polymer solution filtered and the solvent removed in vacuo distilled. It stayed 3.2 kg of polypropylene wax corresponding to a contact yield of 376 g of wax per mgat Ti back.

The product was colorless and hard; its characteristics were: melt viscosity at 170 ° C: 3700 mPas heat of fusion: 60 09 isotactic fraction by IR spectroscopy: 80% flow hardness:> 1000 bar dropping point: 158 to 160 s Comparison search for example 3 a) Preparation of the catalyst by reacting magnesium ethylate with titanium tetrachloride a catalyst was prepared as in Example 1. There was 6.5 on the solid % of the titanium used fixed. A modification of the catalyst with a However, the electron donor did not take place.

b) Polymerization The catalyst prepared in this way became propylene polymerized under the conditions specified in Example 1. One received in one Contact yield of 700 g wax per mgat Ti a colorless, comparatively soft one Medium degree of crystallinity polypropylene wax; Characteristic data: melt viscosity at 170 1800 mPas heat of fusion: 35 09 isotactic fraction by IR spectroscopy: 70 % Flow hardness: approx. 500 bar Example 4 8) Preparation of a catalyst component A - The reaction of magnesium ethylate with titanium tetrachloride became a catalyst precursor produced according to example 1. 6.1% of the amount used was on the solids Titans fixed. 1.8 l of a suspension of this catalyst precursor in diesel oil corresponding to 0.12 gat titanium were then mixed with 37.9 g di-i-amyl ether and 2 Stirred for hours at 100 t. Then 12.0 g of benzoyl chloride were added and the mixture was stirred for 1 hour at 100 s and then washed titanium-free. The finished contact component A contained 3.5% of the titanium originally used as titanium tetrachloride.

b) Polymerization of 1-butene In a 40-1 Ksssel were 15 l of diesel oil and 1.6 kg of 1-butene presented. After heating to 100 s and adding hydrogen gas up to a total pressure of 4.8 bar, 0.77 l of a catalyst mixture was composed from 120 mmol of triethylaluminum, 240 mmol of diethylaluminum chloride, 40 mmol of ethyl benzoate and 114 ml (corresponding to 20 mgat Ti) of the above contact suspension in 1.5 l of diesel oil pumped in.

By continuously adding 2.3 kg of 1-butene per hour and 2 liters of hydrogen and occasional feed of catalyst mixture became the Pressure kept at about 5 bar.

The polymerization temperature was 100 to 110 ° C. After 1.5 hours the reaction was terminated by adding water. the polymer solution filtered and the solvent was distilled off in vacuo. 3.4 kg of polybutene wax remained corresponding to a contact yield of 340 g wax per mgat Ti. The product had a dropping point (DGF M III 3) of 112 Cc, a needle penetration number (OGF M III 9b) from 3 and a melt viscosity of 1500 mPas (170 t). The -1 heat of fusion was 33 Jg and the flow hardness 300 bar.

Comparative experiment to Example 4 a) Preparation of the catalyst by Reacting magnesium ethylate with titanium tetrachloride was a catalyst according to Example 1 produced. 6.5% of the titanium used was fixed on the solid. A post-treatment of the catalyst with an electron donor was omitted.

b) Polymerization With the above catalyst was 1-butene under the conditions specified in Example 4 polymerized. One obtained in a contact yield of 314 9 wax per mgat Ti a soft polybutene wax with a dropping point of 99 s and a needle penetration number of 22. The melt viscosity was 1100 mPas (170 t), the heat of fusion 25 Jg and the flow hardness <100 bar.

Example 5 Polymerization of 1-dctadecene In that described in Example 1 Apparatus were presented with 15 liters of diesel oil and 5.0 kg of octadecene. After heating up 120 Cc was pumped a catalyst mixture consisting of 160 mmol of triethylaluminum, 160 mmol diethylaluminum chloride, 40 mmol benzoic acid ethyl ester and 86 ml (corresponding to 20 mgat fixed titanium) of the contact component A obtained according to Example 1, suspended in 1.5 1 diesel oil, too.

The reaction was allowed to take place at 120 to 130 ° C. for 1 hour. Then it became how stated in Example 1, the contact decomposed and the reaction mixture worked up. 4.7 kg of polyoctadecene wax with a melt viscosity of 960 mPas resulted, measured at 140 Cc, a dropping point of 71, a needle penetration number of 1 up to 2 and a flow hardness of 570 bar.

Claims (8)

Claims 1. Process for the production of polyolefin waxes by homo- or copolymerization of olefins of the general formula R-CH = H2 in the R denotes a hydrocarbon radical with 1 to 38 carbon atoms in one inert solvent as the reaction medium, at temperatures not below 95 T, in the presence of a catalyst system consisting of components A, B and C, in which component A is converted by reacting a viscous titanium compound, reaction product obtained from a magnesium compound and an electron donor, component 6 is an aluminum ore compound and component C is a stereo regulator is characterized. that in component A as a four-ready titanium compound a titanium tetrahalide, a magnesium alcoholate as a magnesium compound and a Electron donor a compound from the group of alcohols, ethers, amines or Carboxylic acids and their derivatives are used, the molar ratio of Mg compound Titanium compound is 1: 0.2 to 1: 5 and the electron donor in an amount from 0.01 to 10 mol, based on the titanium content, the component is present 8 is an organoaluminum compound of the formula Rn AlCl (3-n)> in which R is one Is a hydrocarbon radical with 1 to 30 carbon atoms and n = 1, 2 or 3, and as a stereoregulator C is a compound from the group of carboxylic acid esters, Phosphoric acid amides, ethers or thioethers are used, the molar ratio of Component 8 (based on Al) to component A (based on Ti) at 1: 1 to 30 t 1 and the molar ratio of component C to component A (based on Tb) 0.1: 1 to 10 t 1 and the polymerization temperature is 95 to 150%. 2. The method according to claim 1, characterized. that the catalyst length is dimensioned so that in it 0.1 to 5 milligram atoms of component A (bezagen on their Ti content) per liter of reaction medium. 3. The method according to claim 1, characterized. that to be polymerized α-olefin are mixed in up to 2% by volume of ethylene. 4. The method according to claims 1 and 3, characterized. that the polymerization is regulated with hydrogen. 5. Process according to claims 1, 3 and 4, characterized in that. that one polymerizes propylene. 6 .. Catalyst system for the production of light colored polyolefin waxes with a high degree of crystallinity and melt viscosities of approx. 50 to 100,000 mPas at 170 s by homo- or copolymerization of C 3 to C 40 α-olefins in one organic solvent at 95 to 150 F, consisting of A. a component that the reaction product of a titanium tetrahalide and a magnesium alcoholate in a molar ratio of 0.2 t 1 to 5: 1, the one with an electron donor from the group of the alcohols, ethers, amines or carboxylic acids and their derivatives in an amount from 0.01 to 10 mol, based on the Ti content, had been reacted, represents 8. a component which is an organoaluminum compound of the formula R is AlCl with R = C1- to C30-alkyl and n = n (3-n) 1, 2 or 3, and C. one Component from the group of carboxylic acid esters, phosphoric acid amides, serving as a stereoregulator, Ethers or thioethers, where the molar ratio of component 8 (based on Al) to component A (based on Ti) 1: 1 to 30: 1 and the molar ratio from component C to component A (based on Ti) is 0.1: 1 to 10: 1. 7. Use of a catalyst according to claim 6 for polymerization from 1-olefins with 3 to 40 carbon atoms to waxes with a high degree of crystallinity and Melt viscosities from approx. 50 to 100,000 mPas / 170 ° C. . 8. Polyolefin waxes with a high degree of crystallinity and melt viscosities from approx. 50 to 100,000 mpas / 170 T, obtained according to claims 1 to 5.