WO2004046210A1 - Catalysts used for the production of polyvinyl esters and method for the production of polyvinyl esters - Google Patents

Abstract

The invention relates to novel compounds which can be used as a catalyst and/or catalyst system for polymerizing and copolymerizing vinyl esters and a method for polymerizing and copolymerizing vinyl esters by using said compounds.

Description

Celanese Ventures GmbH

Catalysts for the production of polyvinyl esters and a process for the production of polyvinyl esters.

The present invention relates to a novel compound which can be used as a catalyst in the polymerization and copolymerization of vinyl esters and to a process for the polymerization and copolymerization of vinyl ester using these compounds.

Vinyl esters are olefinic compounds with the following basic structure.

Representatives of this class of compounds are, for example, vinyl acetate (R = CH ₃ ), benzoic acid vinyl ester (R = Ph), vinyl formate (R = H), vinyl propionate (R = C ₂ H ₅ ), pivaiic acid vinyl ester (R = ffiu), vinyl hexanoate ( R = C ₅ Hn), vinyl laurate (R = CnH ₂₃ ).

Polyvinyl esters are polymers accessible from vinyl esters by olefinic polymerization, of which the polyvinyl acetates have by far the greatest technical importance.

Polyvinyl acetate is an important thermoplastic polymer and is used, among other things, as an adhesive (component), paint raw material, for packaging films, for the coating of paper and food (sausage and cheese coatings), as an additive for concrete and as a raw material for the production of polyvinyl alcohols and polyvinyl acetals used (Römpp Lexikon Chemie - Version 2.0, Stuttgart / New York: Georg Thieme Verlag 1999).

In the art, polyvinyl acetate is produced by free radical polymerizations, the polymerization being able to be carried out in solution, in bulk and in emulsion. Azoisobutyronitrile and dibenzoyl peroxide (AIBN / BPO) are mainly used as radical initiators. Because this radical

Polymerizations are fast and uncontrolled is a stereo differentiation ruled out and control the molecular weight and molecular weight distribution very difficult (W. Daniels:... Kirk-Othmer encycl Chem Technol, ^3rd Ed 1983, 23, 817-847.).

Because of the restriction to radical polymerization of vinyl acetate, it has not yet been possible to synthesize polyvinyl acetates in a stereospecific manner with a narrow molecular weight distribution. Polymers with special stereochemistry based on other monomers are used, for example, as substitutes for more expensive polymers or more complicated polymer mixtures due to their special properties.

In contrast to free radical polymerization, living or atom transfer radical polymerization (ATRP) enables control of both the molecular weight distribution and the absolute molecular weights by appropriately adapting the reaction parameters (K. Matyjaszewski, J. Xia, Chem.

Rev. 2001; 101 (12), 2921-2990.). For the controlled polymerization of vinyl acetate by ATRP, an example of an iron catalyst has only been described in the literature (M. Wakioka, K.-Y. Baek, T. Ando, M. Kamigaito, M. Sawamoto, Macromolecυles 2002, 35, 330 -333).

A transition metal catalyzed insertion polymerization with so-called metallocene or post-metallocene contrast enables the synthesis of stereospecific polymers having a narrow molecular weight distribution (W. Kaminsky in Ullmann's Encyclopedia of Industrial Chemistry, 6 ^th Ed., 2002 Electronic Release, Wiley / VCH). This method has been used successfully for many mostly simple α-olefins. With this method, the use of polar monomers has hitherto been restricted to a few acrylates (WO0121670). However, the polymerization of vinyl acetate by a transition metal-catalyzed insertion polymerization with metallocenes or post-metallocenes has so far not been possible.

The object was therefore to develop catalyst systems which avoid the disadvantage of the prior art described and lead to new polymers with special properties based on polyvinyl acetate. Surprisingly, it has now been found that the use of uncharged catalyst systems with metals in oxidation state 0 enables the synthesis of new polyvinyl acetates with special properties.

The present invention relates to compounds of the formula I.

Formula I wherein: M ^{1 is} a transition metal from group 8 to 10 in oxidation state 0, preferably nickel or palladium, and m is the same or different and an integer between 1 and 4 and is the same or different , and an integer between 1 and 4, and

L ^{1 is in} each case identical or different and has a mono- or bidentate ligand

Is donor atoms of the 14th to 16th group of elements, preferably of the following basic structure

and X ¹ is the same or different, and an element of the 14th to 16th group of

Elements, particularly preferably nitrogen or phosphorus, and X ^{2 is in} each case the same or different, and an element of the 14th to 16th group of

Elements, particularly preferably nitrogen or phosphorus, and R ^{1 is in} each case the same or different, and is hydrogen or a Ci - C ₂₀

- is a carbon-containing group, and

R ^{2 is in} each case the same or different, and is hydrogen or a Ci - C ₂₀

- is a carbon-containing group, and R ^{3 is in} each case the same or different, and is hydrogen or a Ci - C ₂₀

- is a carbon-containing group and can also form a cyclic system with R ⁴ or R ⁵ , and

R ^{4 is in} each case the same or different, and is hydrogen or a Ci - C ₂₀

- is a carbon-containing group and can also form a cyclic system with R ³ or R ⁵ , and

R ^{5 is in} each case the same or different, and is hydrogen or a Ci - C ₂ n

- is carbon-containing group, and can also form a cyclic system with R ³ or R ⁴ , and o is 0, 1 or 2, and p is 0, 1 or 2, and q is an integer from 0 to 20 , preferably 0 to 10 and particularly preferably 0, 1 or 2, and r is the same or different and is 1 or 2, and s is the same or different and is 1 or 2, and t is the same or is different and is 1 or 2, and

A is the same or different, and has the following basic structure

wherein R ^{6 is the} same or different, and is hydrogen, or a halogen atom, or a C-ι - C ₂ o- carbon-containing group, and R ^{7 is the} same or different, and is hydrogen, or a halogen atom, or a Ci - C ₂ o- carbon-containing group, where R ¹ and R ^{2 can} also form a cyclic system, and u are each the same or different and are either one or two, and v are each the same or different and are either one or two, except for the compound of formula X.

Formula X

Are a Ci in the context of the present invention - C ₂ o carbon-containing group is preferably the radicals CC ₂ -alkyl, particularly preferably methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl , t-butyl, n-pentyl, s-pentyl, cyclopentyl, n-hexyl, cyclohexyl, n-octyl or cyclooctyl, Ci - C ₂₀ - alkenyl, particularly preferably ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, Octenyl or cyclooctenyl, Ci - C ₂ o - alkynyl, particularly preferably ethynyl, propynyl, butynyl, pentynyl, hexynyl or octynyl, C6 - C ₂ o - aryl, particularly preferably phenyl, biphenyl, naphthyl or anthracenyl, Ci - C ₂₀ - fluoroalkyl , particularly preferably trifluoromethyl, pentafluoroethyl or 2,2,2-trifluoroethyl, C ₆ -C ₂₀ -

Aryl, particularly preferably phenyl, biphenyl, naphthyl, anthracenyl, triphenylenyl, [1, V; 3 ', V'] terpheny \ -2'- \, binaphthyl or phenanthrenyl, C ₆ -C ₂₀ -fluoroaryl, particularly preferably tetrafluorophenyl or heptafluoronaphthyl , CrC ₂₀ alkoxy, particularly preferably methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy or t-butoxy, C ₆ -C ₂ o-aryloxy, particularly preferably phenoxy, naphthoxy .

Biphenyloxy, anthracenyloxy, phenanthrenyloxy, C ₇ -C ₂ o-arylalkyl, particularly preferably o-tolyl, m-tolyl, p-tolyl, 2,6-dimethylphenyl, 2,6-diethylphenyl, 2,6-di-i-propylphenyl , 2,6-di-t-butylphenyl, ot-butylphenyl, mt-butylphenyl, pt-butylphenyl, C ₇ -C ₂ o-alkylaryl, particularly preferably benzyl, ethylphenyl, propylphenyl, diphenylmethyl, thphenylmethyl or naphthalinylmethyl, C -C ₂ o-aryloxyalkyl, particularly preferably o-methoxyphenyl, m-phenoxymethyl, p-phenoxymethyl, C-ι ₂ - C ₂₀ aryloxyaryl, particularly preferably p-phenoxyphenyl, C ₅ -C ₂ o-heteroaryl, particularly preferably 2-pyridyl, 3rd Pyridyl, 4-pyridyl, quinolinyl, isoquinolinyl, acridinyl, benzoquinolinyl or benzoisoquinolinyl, C ₄ -C ₂ o-heterocycloalkyl, particularly preferably furyl, benzofuryl, 2-pyrolidinyl, 2-indolyl, 3-indolyl, 2,3-dihydroindolyl, Cs-C ₂ o-arylalkenyl, particularly preferably o-vinylphenyl, m-vinylphenyl, p-vinylphenyl, C ₈ -C _20- arylalkynyl, particularly preferably o-ethynylphenyl, m-ethynylphenyl or p-ethynylphenyl, C ₂ -C ₂ o - heteroatom-containing group, particularly preferably carboxymethyl, carbonyl, benzoyl, oxybenzoyl, benzoyloxy,

Acetyl, acetoxy or nitrile understood, where one or more C 1 -C ₂₀ carbon-containing groups can form a cyclic system.

According to the invention, preferred olefinic ligands A are styrene, norbornene, butadiene, cyclooctadiene, cyclohexene, vinyl acetate, methyl acrylate, methyl methacrylate,

Acrylic acid, ethyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate are used.

Illustrative but non-limiting examples of compounds of formula I are listed below. In particular, the non-restrictive selection applies to the type of olefinic ligand A, which can be selected according to formula I.

The compound of formula X is from J. Organomet. Chem. 1989, 367, 233-242, already known. The synthesis described there is also suitable for the preparation of the compounds of the formula I according to the invention and can be illustrated using the example below:

The compounds of formula I are as catalysts in the o ymer sat on of

Suitable for vinyl esters.

Another object of the present invention is a process for the polymerization of vinyl esters using the compounds according to the invention, wherein both the homopolymerization of

Vinyl esters as well as the copolymerization of vinyl esters with other olefins is understood.

Examples of other olefins are 1-olefins having 2 to 20, preferably 2 to 10, carbon atoms, such as ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-decene, 4-methyl-1-pentene or 1-octene, styrene, dienes such as 1,3-butadiene, 1,4-hexadiene, vinyl norbornene,

Norbornadiene, ethylnorbornadiene and cyclic olefins such as norbornene, cyclopentadiene, tetracyclododecene or methylnorbornene, and polar monomers such as methyl acrylate, methyl methacrylate, acrylic acid, ethyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate.

In the process according to the invention, vinyl acetate is preferably homopolymerized, or vinyl acetate is copolymerized with one or more 1-olefins having 2 to 8 carbon atoms, such as ethene, propene, styrene, norbornene, methyl acrylate, methyl methacrylate, acrylic acid or butadiene.

The polymerization is carried out at a temperature of from -20 to 300.degree. C., preferably from -20 to 200.degree. C., very particularly preferably at from -20 to 100.degree. The pressure is 0.5 to 2000 bar, preferably 1 to 64 bar. The polymerization can be in solution, in Mass, in suspension or in emulsion, continuously or discontinuously, one or more stages. Suitable solvents for the polymerization are, for example, aliphatic hydrocarbons such as pentane, hexane and the like or aromatic hydrocarbons such as benzene, toluene, xylenes and the like, or ethers such as diethyl ether, dibutyl ether, methyl tert-butyl ether, tetrahydrofuran, dioxane, anisole, diphenyl ether and Ethylphenyl ether, including halogenated solvents such as dichloromethane, trichloromethane, chlorobenzene, bromobenzene and the like, as well as ethyl acetate, acetone, N, N-dimethylformamide, ethylene carbonate, methanol, ethanol, propanol, i-propanol or water. Mixtures of different solvents in different solvents can also be used

Ratios are used according to the invention.

Optionally, additional cocatalysts or additives can be used in the process described to improve activities and to change tacticities in the polymer.

Preferred cocatalysts or additives are compounds of the formula II

[( ² ) _x (R ⁹ ) _y ] _z

Formula II

wherein

M ^{2 is in} each case the same or different and is a metal from the 1st to 14th group of the periodic table, preferably lithium, magnesium, scandium, titanium, boron, aluminum, silicon, tin, particularly preferably boron and aluminum, and R ^{9 is the} same or different and is hydrogen, a halogen atom or a Ci

C ₂₀ - carbon-containing group, and x is an integer between 1 and 5, and y is an integer between 1 and 5, and z is an integer between 1 and 5. The cocatalysts or additives of the formula II used according to the invention are one or more compounds of the type of an aluminoxane and / or another Lewis acid.

Cocatalysts which can form the catalyst system together with a transition metal complex of the formula I according to the invention are particularly preferred. In addition to at least one compound of the formula I, this catalyst system contains at least one compound of the formula II of the aluminoxane or Lewis acid type. Suitable cocatalysts which can form the catalyst system according to the invention together with a compound of the formula I are described in WO 0148034. The catalyst systems according to the invention, which can be formed from a compound of the formula I and the cocatalysts described in WO 0148034, are also included in the present invention.

Illustrative but non-limiting examples of cocatalysts which can form the catalyst system together with a compound of the formula I are: aluminoxanes, which are described, for example, in JACS 1 17 (1995), 6465-74 and Organometallics 13 (1994), 2957-2969 , or Lewis acids, which consist for example of boron or organoaluminum compounds, or

Cocatalysts described in EP-A-924223, DE-A-19622207, EP-A-601830, EP-A-8241 12, EP-A-8241 13, EP-A-81 1627, WO97 / 11775 and DE-A -19606167 are described.

According to the invention, Lewis acids which are optionally used are those which contain at least one or more atoms of lithium, magnesium, scandium, titanium,

Contain boron, aluminum, silicon and / or tin. It is particularly preferred to use at least one organoboron or organoaluminum compound which contains C1-C20- carbon-containing groups, such as branched or unbranched alkyl or haloalkyl, such as e.g. Methyl, propyl, isopropyl, isobutyl, trifluoromethyl, unsaturated groups, such as aryl or haloaryl, such as phenyl, tolyl, benzyl groups, p-

Fluorophenyl, 3,5-difluorophenyl, pentachlorophenyl, pentafluorophenyl, 3,4,5-trifluorophenyl and 3,5-di (thfluoromethyl) phenyl. Illustrative but non-limiting examples of the optionally used cocatalysts are:

Trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tributyl aluminum,

Trifluoroborane, triphenylborane, tris (4-fluorophenyl) borane, tris (3,5-difluorophenyl) borane, tris (4-fluoromethylphenyl) borane,

Tris (pentafluorophenyl) borane, tris (tolyl) borane, Ths (3,5-dimethylphenyl) borane,

Tris (3,5-difluorophenyl) borane, tris (3,4,5-trifluorophenyl) borane.

CIAI (Me) ₂ , AI (OMe) ₃ ; AI (OEt) ₃ ; AI (O-t7Pr) ₃ , AI (O-Pr) ₃ , AI (Or> Bu) ₃ ; AI (O-sBu) ₃ ; Al (O- fßu) ₃ ; MeAI (O-2,6-di-butylphenyl) ₂ , AI (O-2,6-di-butylphenyl) ₃ ; TiCI ₄ , Ti (OMe) ₄ ; Ti (OEt) ₄ ; Ti (O-nPr) ₄ ; Ti (O-Pr) ₄ ; Ti (O-nBu) ₄ ; Ti (O-sBu) ₄ ; Ti (O-βu) ₄ ; Sc (OTf) ₃ , MgBr ₂ ,

SiCI, SnCI ₄ , LiCIO ₄ , LiOMe; LiOEt; LiO-Pr; LIO / Pr; LiO-Bu; LiO-sBu; LiO tBu;

BCI ₃ , B (Et) ₃ , B (Ph) ₃ , B (OMe) ₃ ; B (OPh) ₃ , B (OEt) ₃ ; B (O-nPr) ₃ ; B (O- / Pr) ₃ ; B (O-nBu) ₃ ;

B (O-sBu) ₃ ; B (O-ft3u) ₃ .

Furthermore, the catalysts of the invention can be used both homogeneously and heterogeneously supported. The carrier component of the catalyst system according to the invention can be any organic or inorganic, inert solid, in particular a porous carrier such as talc, inorganic oxides and finely divided polymer powders (e.g. highly porous polyolefins such as polyethylene, polypropylene, polystyrenes, copolymers, or polar polymers such as e.g.

Polyurethanes, polymethacrylates, polymethyl methacrylates, polyvinyl acetate, polyacrylonitrile, polyethylene glycol or copolymers).

Suitable inorganic oxides can be found in ll.-VI. Main group of the periodic table and the lll.-IV. Subgroup of the Periodic Table of the Elements.

Examples of preferred oxides as carriers include silicon dioxide, hydrotalcite, aluminum oxide, and mixed oxides of the elements calcium, aluminum, silicon, magnesium, titanium and corresponding oxide mixtures. Other inorganic oxides that can be used alone or in combination with the last-mentioned preferred oxidic supports are, for example, MgO, ZrO ₂ , TiO ₂ or B ₂ O ₃ , to name just a few. The invention is illustrated by the following examples which, however, do not restrict the invention.

General information: The production and handling of the organometallic compounds was carried out with the exclusion of air and moisture under an argon protective gas (Schlenk technique or glove box). All required solvents were flushed with argon before use and absoluteized using a molecular sieve.

Example 1 :

In a heated Schlenk flask, 275 mg (1 mmol) of bis (1, 5-cyclooctadiene) nickel (0) in 10 ml abs. Dissolved diethyl ether and mixed with 0.2 ml (1 .3 mmol) of N, N, N ', N'-tetramethylethylenediamine. The resulting yellow solution is mixed with 0.18 ml (2 mmol) of methyl acrylate and slowly

Cooled to -78 ° C. The orange solid which precipitates is allowed to settle and the supernatant red solution is decanted off. The solid is then twice more with 4 ml of abs. Washed diethyl ether and finally dried in vacuo. Yield: 291 mg (0.84 mmol, 84%). ¹ H NMR (500 MHz, toluene-d ₈ , 233 K): δ = 3.50

(bs, 8H, OCH ₃ , CH-olefinic), 3.37 (bs, 2H, CH-olefinic), 1.91 (bs, 2H, NCH), 1.69 (bs, 2H, CH-olefinic), 1.15 (bs, 8H, NCH ₃ , NCH). Example 2:

Polymerization of vinyl acetate with the following catalyst

20.1 mg (32.0 μmol) of the catalyst are placed in a heated flask and 1.85 ml (20.0 mmol) of freshly distilled vinyl acetate are added. The reaction mixture is then stirred at 60 ° C for twelve hours. The reaction is then stopped by adding 2 ml of acidic methanol and the mixture is concentrated to a residual volume of 1 ml. The polymer formed is precipitated by adding 20 ml of heptane and the supernatant solution is decanted off. The residue is dried in an oil pump vacuum. Yield: 350 mg (4.06 mmol, 20%). ¹ H NMR (500 MHz, CDCI ₃ ): δ = 4.86 (bs, 1 H, CH), 2.01 (bt, 3H, COCH ₃ ), 1.75 (bd, 2H, CH ₂ ). ¹³ C-NMR (500 MHz, CDCI ₃ ): δ = 170.4 - 170.0 (C = O), 68.5 - 66.5 (CH), 40.5 - 38.5 (CH ₂ ), 21.1 - 20.8 (CH ₃ ).

Claims

claims

1. Compounds of formula I.

Formula I wherein M ^{1 is} a transition metal from group 8 to 10 in oxidation state 0, preferably nickel or palladium, and m is the same or different and an integer between 1 and 4 and n is the same or different , and an integer between 1 and 4, and L ¹ is the same or different and is a mono- or bidentate ligand with donor atoms of the 14th to 16th group of elements, preferably of the following basic structure

and X ¹ is the same or different, and an element of 14th to 16th

Group of elements, particularly preferably nitrogen or phosphorus, and X ^{2 is in} each case the same or different, and an element of the 14th to 16th

Group of elements, particularly preferably nitrogen or phosphorus, and R ^{1 is in} each case the same or different, and is hydrogen or a Ci -

C _{2 is} o- carbon-containing group, and R ^{2 is in} each case identical or different, and is hydrogen or a Ci -

C _{20 is a} carbon-containing group, and R ^{3 is in} each case identical or different and is hydrogen or a Ci -

C _{20 is a} carbon-containing group, and also a cyclic group with R ⁴ or R ⁵

System can form, and R ^{4 is in} each case the same or different, and is hydrogen or a Ci -

C _{20 is a} carbon-containing group and can also form a cyclic system with R ³ or R ⁵ , and

R ^{5 is in} each case the same or different, and is hydrogen or a Ci -

C _{20 is a} carbon-containing group, and also a cyclic group with R ³ or R ⁴

Can form a system, and o is 0, 1 or 2, and p is 0, 1 or 2, and q is an integer from 0 to 20, preferably 0 to 10 and particularly preferably 0, 1 or 2 , and r is the same or different and is 1 or 2, and s is the same or different and is 1 or 2, and t is the same or different and is 1 or 2, and

A is the same or different, and has the following basic structure

where R ^{6 is the} same or different, and is hydrogen, or a

Halogen atom, or a Ci - C ₂₀ - containing group, and

R ^{7 is the} same or different and is hydrogen, or a

Halogen atom, or a Ci - C ₂₀ - carbon - containing group, whereby R ¹ and R ^{2 can} also form a cyclic system, and u are each the same or different and are either one or two, and v are each the same or different and are either one or two, except for the compound of formula X.

Formula X

2. A catalyst system comprising at least one compound of the formula I and at least one compound of the formula II

[(M ² ) _x (R ⁹ ) _y ] _z

Formula II

wherein

M ^{2 is in} each case identical or different and is a metal of the 1st to 14th group of the periodic table, preferably lithium, magnesium, scandium, titanium, boron, aluminum, silicon, tin, particularly preferably boron and

Aluminum, and R ^{9 is the} same or different and is hydrogen, a halogen atom or one

Ci - C ₂ o - carbon-containing group, and x is an integer between 1 and 5, and y is an integer between 1 and 5, and z is an integer between 1 and 5.

3. Use of at least one compound according to claim 1 for the production of polyvinyl esters.

4. Use of at least one catalyst system according to claim 2 for the production of polyvinyl esters.

5. A process for the preparation of polyvinyl esters, characterized in that at least one compound according to claim 1 is used as a catalyst.

6. A process for the preparation of polyvinyl esters, characterized in that at least one catalyst system according to claim 2 is used.