FI85588C - FOERFARANDE FOER REGLERING AV MOLEKYLVIKTSFOERDELNINGEN OCH MOLEKYLVIKTEN AV OLIGOMERISATIONS- ELLER POLYMERISATIONSPRODUKTER AV ETEN. - Google Patents

Description

85588

Method for adjusting the molecular weight distribution and molecular weight of an ethylene oligomer / polymerization product For the regulation of molecular weight formation and molecular weight of oligomerizations or polymerization products of ethanol 5

The invention relates to a process for controlling the molecular weight distribution and molecular weight of an ethylene oligomerization / polymerization product, wherein the ethylene oligomerization and / or polymerization process uses nickel ylide bound to a crosslinked polystyrene or used with a promoter as a catalyst.

α-olefins are known to have many applications depending on the chain length of the olefins. For example, C12 to C4 olefins are used to prepare the corresponding sulfonate and ethoxylate type biodegradable detergents. Alcohols prepared from C8-C12-α-olefins, on the other hand, have significant use, especially as plasticizer alcohols. 1-Decene, on the other hand, is increasingly used in the manufacture of poly α-olefin-type synthetic lubricants. The shortest chain C4 to Cf olefins have use as comonomers of polyolefins, especially LLDPE.

Thus, several catalysts are known for the dimerization, oligomerization and polymerization of olefins. For example, GB Patent Publication No. 1,239,812 discloses a catalyst for the oligomerization of olefins comprising a metal-containing organic polymer containing a Group VIII metal atom and a Lewis acid-like compound. Known catalysts for the oligomerization of olefins are generally organometallic compounds, for example organoaluminum compounds, which are linked to a transition metal compound with low molecular weight ligands containing Group V or VI substances (nitrogen, oxygen, phosphorus or sulfur). U.S. Pat. No. 4,115,468 discloses a two-component catalyst containing an organoaluminum compound and, for example, a quinyl-containing siloxane rubber of • 35; bound to a nickel salt, for dimerization of olefins.

Today, increasingly powerful ethylene oligomerization catalysts are being developed to provide high reaction rates and yields at low temperatures and pressures. In this regard, U.S. Patents 4,293,502 and 4,293,727 disclose ylide-type nickel catalysts for the oligomerization of ethylene.

The use of nickel phosphine catalysts bonded to crosslinked polystyrene as an oligomerization catalyst is known from U.S. Patent 3,933,770 (polymer halogenated crosslinked polystyrene) and DE Patent 2,230,739 (polymer styrene-divinylbenzene). Catalysts of the latter type are preferred in the sense that they can be recovered from the reaction mixture and reused.

This patent proposal relates to a process by which the molecular weight distribution and molecular weight of ethylene oligomerization products can be adjusted when using catalysts of the type mentioned in the previous paragraph as catalysts.

The process according to the invention for adjusting the molecular weight distribution and molecular weight of ethylene oligomerization and polymerization products is mainly characterized in that in the process the product distribution and molecular weight are controlled by modifying the catalyst system by varying the degree of catalyst crosslinker or crosslinking. with fin and / or bis-cyclooctadiene nickel chelate.

25

Preferred embodiments of the invention have the features of the subclaims.

The method allows the product distribution of these products to be controlled over a fairly wide range (MW - 100 to 115,000) either in the direction of short or long chain olefins, depending on the promoters used or the degree of crosslinking of the polystyrene as carrier.

. ' . The invention relates in particular to those processes in which the oligo-35 'polymerization of ethylene is carried out using nickel ylide of the following formula I as catalyst, either a) supported on a support, in particular cross-linked polystyrene, preferably 1 to 4% divinylbenzene, or b) together triphenylphosphine or with bis-cyclooctadiene nickel chelate.

5 / V> / 7, (1) (COD) jN i + Ph3P + Ph3P = * CHCOPh _ \ ^ (I)

Ph / ^ CM

N * i io! \ \ ft s 0 /%

Ph - phenyl 15 (COD 1 -bis-cyclooctadiene nickel

The coupling to the crosslinked polystyrene (1 to 4% divinylbenzene) has been carried out chemically and the catalysts then correspond to the structure II obtained in reactions 2 and 3.

20 (2> © <Ö) TMEDA * —2 ^ -> © <5) ^

‘O

··: '/ Ph-C-CHaBr

‘• 25 / C6H50! C

(3> <© 30 λ ®r? Fh p

Ocop) 2Ni + PPh5 -> (2)

Ph O

/ \ / C \ - 35 Ph3P 0 ^ <t 85588 (II)

Ph - phenyl (COD) jNi - bis-cyclooctadiene nickel PS - cross-linked polystyrene 5 TMEDA - tetramethylethylenediamine

In particular, the invention relates to those processes in which the molecular distribution of an oligomer product prepared with a Ni-ylide catalyst is adjusted to either longer-chain or short-chain olefins due to the intended use. A significant shift to the region of long chain, even polymeric products is obtained as the degree of crosslinking of the polystyrene support increases (e.g. 2 or 4% crosslinked polystyrene). The addition of bis-cyclooctadiene in the oligomerization step also causes the oligomerization distribution to shift into the region of long chain products.

A suitable (COD) jNi amount is 3 to 5 times the amount of nickel contained in the catalyst.

Excess (0.5 to 1.0 mol) of triphenylphosphine in the phosphine yl-nickel catalyst formula, in turn, directs the oligomerization distribution downstream of the boiling α-olefin products.

: · .: By adjusting the phosphine catalysts in a certain way according to the invention, the · · catalysts directly produce benign LLDPE.

The reaction products according to the invention are suitable depending on the molecular weight ... and its distribution, e.g. the processing properties of the polyolefins. and as starting materials for synthetic lubricants. Products with a higher molecular weight can already be used as such in various grades of polyethylene.

30

Suitable solvents for carrying out the ethylene oligomerization reaction include aromatic or aliphatic hydrocarbons or mixtures thereof.

Suitable methods for recycling the supported catalyst include film separation methods (1 and 2% crosslinked polystyrene) or filtration (4% crosslinked polystyrene).

li 5 85588

A more detailed preparation of the catalysts according to the invention is set out below.

Preparation of the ylide (catalyst I): - <Q) -PPK2 * BrCnjU ^ - ^^ - PPUjCHjCPPlV- phosphonium salt * / ~ \ PK 10 € K · ^? - * λΟλ ^ 'TT—> PPK3 / Il f ή \> - 15 5 ^

THF - tetrahydrofuran (I) I

The salt of triphenylphosphine and bromoacetophenone formed in the first step was purified either by decanting the solution from the precipitate or by pressure filtration under N 2. The ylide was liberated by treating the resulting bromide with a base (calcium phenolate or sodium carbonate) n.

16 kg and crystallizing the product from benzene. The ni ylide was prepared by stirring the above ylide, bis-cyclooctadiene nickel and triphenylphosphine in a ratio of 1: 1: 1 at room temperature for about 24 h. Catalyst I was purified by crystallization from n-octane.

Preparation of polydyrene-attached ylide (catalyst II):

The following reaction was carried out, for example, in a 50 ml conical flask: 30 @ - ^^^ - PPh2 + BrCH2CPh - * (g) - ^^ PPh2CH2CPh] * Br ~ phosphonium salt · PS - crosslinked polystyrene 35 6 85588

Preparation (1) Phosphinated polystyrene was transferred to a reaction vessel in a nitrogen cabinet (2) THF was added in a nitrogen cabinet (3) Swollen with stirring 5 (4) β-Bromoacetophenone was added to the vessel and stirring was continued at 20 ° C for 18 hours (5). with water b) The following reaction was performed in an Erlenmeyer flask: 10 (g> <^^> - PPh2CH2CPh] V ~ + 0OV - ^ ® - (^) - PPh2 = CHCPh ylidl

PU3P

15 Preparation: -3 ^

PS

(1) The phosphonium salt was transferred to a reaction vessel PK (of (2) THF was added in a nitrogen bag p

(3) Stirred at 20 ° C for 1 hour

(4) K-phenoxide solution was added with a double-ended needle Jζ, -ΡΚ 20 (5) Stirred at 20® C for 16 hours PV \ -jP O ^ (6) Pressure filtered in a nitrogen bag (I) (7) The product was washed with THF (10 ml), THF: H 2 O (1: 1) (50 mL), H 2 O (60 mL) and THF (40 mL): -25 The reaction with (COD) jNi and triphenylphosphine was performed as above.

The invention can be further illustrated by the following examples.

30 EXAMPLES 1-4

The pressure reactor was charged with the catalyst I and the solvent of the formula I and (and also in Examples 3 and 4 (COD) jNi) in a nitrogen cabinet. The reactor was heated to 50 ° and pressurized with ethylene to a pressure of 50-60 bar.

-: - 35 The pressure was kept constant (50 bar) by means of an ethylene feed throughout the reaction (2 h). Gaseous and liquid products were analyzed by gas chromatography

II

7,85588 graphically and solid intake was determined by weighing and molecular weight distribution by gel permeation chromatography (GPC).

The results and experimental conditions are shown in Table 1 and Figures 1 and 2. The results show that a widely varying molecular weight distribution in the products is obtained, which can be further controlled by e.g. (COD) jNi, the addition of which results in longer chain polymer products.

10 EXAMPLES 5-10

The pressure reactor was charged with a catalyst of formula II and a solvent in a nitrogen cabinet. In the oligomerization, ethylene was first fed at a pressure of about 40-50 bar, then the stirring was switched on and heating of the mixture was started. The reactor was heated to 75 ° and pressurized with ethylene to a pressure of 50-55 bar. The reaction time was 4 h, 6 h, 9 h, 12 h and 15 h. All ethylene was consumed in Examples 5 and 6. The gaseous and liquid products were analyzed by gas chromatography and the solid intake was determined by weighing and its molecular weight distribution by GPC. The results 20 and the experimental conditions are detailed in Tables 3 and 4 and Figures 3-5. Comparing the results with the results of Examples 1-4, it is found that the crosslinked polystyrene-bound catalyst causes a widely varying molecular weight distribution in the ethylene polymerization product, and that product distribution and molecular weight can be controlled by varying the degree of crosslinking of .25 polystyrene (0-4%). A low degree of crosslinking (about 1%) gives a large amount of C6-Ca products and a high number of higher polymers.

8 85588 1 EXAMPLES Oligomerizations with Catalyst II of Formula II containing 11-1¾ 1% cross-linked PS (Table 4).

5 Effect of PPhj increment

Catalyst: 11-12.288 10 PS-ylide 3.14 g (COD) 2Ni 1.9 g / 6.9 mmol PPI13 1.65 g / 6.3 mmol yield 13.0 g 15 Oligomerization:

The catalyst batches were weighed into brown small flasks, 10 ml of toluene was added and the flasks were stored in a nitrogen cabinet (parafilm around the cap).

20: A 300 ml Parr steel vessel with an engine mix was used as an autoclave.

,. The catalyst and toluene were placed in an autoclave in a nitrogen cabinet. The autoclave was pressurized to 48 bar, stirred and the reaction mixture was heated in an electric bath. Rapid heating to 50 ° C was used, after which the mixture was heated at a slow heating rate to a reaction temperature of 75 ° C to avoid an exothermic reaction. When 75 ° C was reached and ethylene began to run, ethylene 30 was introduced into the mixture. Contrary to previous determinations, the oligomerization used a continuous feed of ethylene at a constant pressure of 48 bar.

• · Table 4 and Figures 6-8 summarize the results of the oligomerization reactions. The reaction mixture 11 was heated to 65 ° C with rapid heating - .. · 35 control from which slow heating was continued. The reaction temperature rose to over 75 ° C (max. 138 ° C) for 6 min.

li 9 85588 1 The amount of PPh 3 is 1.5 times the molar amount of PPh 3 used in the preparation of the catalyst in experiments 12 and 13. In Experiment 14, the amount of ΡΡΙίβ is double that of Experiments 12 and 13.

Experiment 15 has a reaction time of 4 hours (such as 12 and 13), but the autoclave with its reaction mixtures was pressurized at 34 Bar at room temperature for 2 days, during which time the reaction proceeded consuming all ethylene.

Gas analysis and mass spectroscopy were used to analyze the products. In the quantitative analysis of liquid products, the internal standard was dean. In determining the mass of the wax (polyethylene), the mass of the catalyst used in the reaction was subtracted from the amount of dried wax filtered out of the liquid phase.

15

A gas sample of the reaction mixture was taken in a gas chromatograph (Perkin Elmer 8500) gas supply funnel (100) after the reaction was complete with the reaction mixture at room temperature. The peaks given by the gas chromatogram were identified by mass spectroscopy as ethylene, 1-butene-20, 1-hexene and toluene. Toluene was further tested; retention time by heating toluene alone in an autoclave to the reaction temperature and taking a gas sample. A 25 m long silica capillary column containing a BP 1 5 m λ "thick liquid phase was used as the column.

* ’25 The amount of gases was calculated from the weighing results of the autoclave using single resonances (weighing of the autoclave when the gases were inside and after the gases were vented).

The formation of gaseous products in the oligomerization reaction was monitored. As early as two minutes after the start of the reaction, some butene had formed as well as hexene. The proportion of both components increased as the reaction proceeded.

• φ r · · The addition of PPh3 to the reaction shifts the peak of the oligomer distribution to the light 35 alkenes. In Experiment 14, where the amount of PPh3 was three times the molar amount of PPh3 used to prepare the catalyst, 1-butene • * · ίο 8 5 588 1 accounted for 64.7% of the oligorerate production and in Experiments 12 and 13 for 50.9% and 47.5%. In these reactions, C4 to C2q accounted for up to 96% of the oligomers.

5 The share of wax in the total catch decreases with the addition of PPh 2 (76.5 -> up to 23.1%), but at the same time the activity of the catalyst decreases.

To summarize the oligomerization of ethylene with catalysts attached to polystyrene, it is found that a catalyst attached to 1% crosslinked polystyrene produces wax in addition to oligomers. The amount of wax can be reduced by adding triphenylphosphine to the autoclave with the catalyst. At the same time, however, the total activity of the catalyst decreases as a function of the molar amount of triphenylphosphine added. Thanks to triphenylphosphine, the proportion of light C4 to C 1-4 alkenes increases from oligomers. The addition of triphenylphosphine to the reaction causes an increase in the weight average molecular weight of the wax and also an increase in the number-average molecular weight. As the amount of triphenylphosphine used to prepare the catalyst is reduced, the total activity of the catalyst decreases, but at the same time the proportion of wax in the total products decreases and the proportion of light 1-alkenes increases.

Of the catalysts attached to crosslinked polystyrene, the most active was the catalyst containing 1% PS for both oligomer and wax production. The wax accounted for less than 50% of the total product in the products of the 1% 25 PS catalyst when the catalyst dispersion contained 59 mg / 40 ml of nickel. Wax share face! as polystyrene crosslinking increases. The catalyst with the weakest total activity of 4% cross-linked PS produced relatively the most wax 90% of the total product.

30

In addition to the crosslinking of PS, the increase in the wax content was due to a small amount of catalyst (nickel), an increase in the volume of the solvent, and a decrease in the reaction temperature.

35 Molecular weight distributions in waxes varied widely. The lowest π 85588 1 polydispersity value 4 was 4 in the waxes produced by the catalyst containing cross-linked PS and the highest 94 in the waxes containing 2% PS.

The catalyst containing 1% crosslinked PS produced a wax with a polydispersity of 12. Mw was 5600 and Mn 460. As the crosslinking of polystyrene increased, higher molecular weight polymers of ethylene were obtained. The highest molecular weights were achieved with catalysts containing 2% cross-linked PS.

10 The catalyst containing uncrosslinked PS (Mw 209000) gave rise to a low molecular weight wax.

The oligomers predominated in light 1-alkenes at 1% and 2% in the products produced by the cross-linked PS catalysts. Cg - C ^ q accounted for the highest 2% of 15 alkenes in PS products (32-57%) and decreased by 1% in PS products (21-37%). The lightest oligomers were the least with the catalyst support being 4% cross-linked PS, with the peak of oligomers having a peak distribution in heavy alkenes (C8-C2q 8-22%). The distribution peak also shifted to heavy alkenes in 1% and 2% PS 20 products upon dilution of the catalyst dispersion.

25 30

»· I

35

Claims (6)

12 85588 A process for controlling the molecular weight distribution and molecular weight of an ethylene oligomerization / polymerization product, wherein the ethylene oligomerization and / or polymerization process uses a crosslinked polystyrene-bonded or promoter-driven nickel product as a catalyst and a catalyst, characterized in that by varying the degree of crosslinking of the supported polystyrene, and / or by using a catalyst system in combination with triphenylphosphine and / or bis-cyclooctadiene nickel chelate. Process according to Claim 1, characterized in that the degree of crosslinking is changed in the range from 0 to 4% in order to obtain various ethylene oligomerization and / or polymerization products with an average molecular weight in the range from Mw to 1000 to 115,000. Process according to Claim 1 or 2, characterized in that the amount of nickel-bis-cyclooctadiene (COD) 2 Ni is 3 to 5 times the amount of nickel contained in the catalyst. Process according to one of Claims 1 to 3, characterized in that the catalyst is modified by means of (COD) jNi when a high proportion of high molecular weight products is desired. Process according to one of Claims 1 to 4, characterized in that when the product distribution and the molecular weight are modified by means of a catalyst bound to a crosslinked polystyrene using a degree of crosslinking of about 1% to 2%, products in the range C6 to Ca, in particular C6 to C10 and approx. 4% crosslinking when higher products are desired. Process according to one of Claims 1 to 5, characterized in that a higher amount of triphenylphosphine results in a higher amount of C 6 -C 8 products, in particular C 4 -C 10 products. li 13 85588