RU2414965C1 - Method of preparing catalyst for polymerisation of norbornene - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: disclosed method relates to preparing a catalyst for addition polymerisation of norbornene to polynorbornene. Described is a method of preparing a catalyst for addition polymerisation of norbornene based on complexes of zero-valent nickel and BF₃OEt₂ involving use of catalyst systems of the composition (L)_nNi(PR₃)₂/BF₃OEt₂, where n=1, 2; L=PR₃ or ethylene; R=Ph, OC₆H₄CH₃-o combined with a controlled amount of water as a modifying component, and the process is carried out in a medium of organic solvent, e.g. toluene in molar ratio of boron to nickel B: Ni=50:1-600:1, ratio H₂O/Ni=2-104 and temperature 10-80°C.

EFFECT: high efficiency of the norbornene polymerisation process.

3 tbl, 8 ex

Description

The present invention relates to the field of producing a catalyst for the additive polymerization of norbornene (bicyclo [2.2.1] heptene-2) in polynorbornene, which are used for the production of coatings in electronics, telecommunications materials, optical lenses, substrates for plastic displays, photoresistors for the production of chips and displays, dielectrics for semiconductors.

Additive polymerization proceeds with the opening of a double bond and leads to polymers containing unchanged cyclic structures in the main chain. Such polymers are characterized by good thermal and chemical stability, amorphous properties, high transparency in the IR, visible and UV regions, low refractive index, narrow decomposition temperature, and isotropy of dielectric properties. This makes them promising for the production of coatings in electronics, telecommunications materials, optical lenses, substrates for plastic displays, photoresistors for the production of chips and displays, dielectrics for semiconductors.

Known catalysts for the additive polymerization of norbornene (NB): (1) one-component nickel catalysts represented by cationic complexes with bulky counterions / US 6103920 C07F 15/04; C08F 4/06; C08F 4/70, 2000, US 5741869 C08F 4/80; C08F 32/08; C08F 4/00; C08F 32/00, 1998, US 5,468,819; C08F 4/70; C08F 4/30; C08F 4/42; C08F 32/00; 1995 /; (2) neutral nickel (II) complexes in combination with methylaluminoxane (MAO), a combination of triethylaluminium (AlEt ₃ ) and tris (pentafluorophenyl) borate (B (C ₆ F ₅ ) ₃ ) / US 7247687 C08F 4/06; B01J 31/00; C07F 15/02 2006 /, a combination of triisobutylaluminum and B (C ₆ F ₅ ) ₃ / US 5629398 C08F 4/54; C08F 4/602; C08F 4/64 1997 /; (3) nickel complexes (0) in combination with a combination of AlEt ₃ and B (C ₆ F ₅ ) ₃ / Y. Jang, H.-K.Sung, Lee S., C. Ba, Polymer 46 (2005) 11301- 11310 /.

The disadvantage of such catalytic systems is the use of expensive, unstable organometallic complexes of nickel, boron and organoaluminum compounds.

The closest known solution to a similar problem in technical essence is a method for producing a catalyst for the polymerization of norbornene by reacting nickel tetrakistriphenylphosphine (0) with boron trifluoride etherate / G. Myagmarsuren, O-Yong Jeong, Son-Ki Ihm, Appl. Catal. A: Gen. 255 (2003) 203-209.

However, such catalytic systems are characterized by low reproducibility and a spontaneous increase in the process temperature.

The task of the invention is to increase the efficiency of the polymerization of norbornene.

This object is achieved by the fact that in the process for the preparation of a catalyst for the additive polymerization of norbornene based on complexes of zero-valent nickel and BF ₃ OEt ₂ , catalytic systems of the composition (L) _n Ni (PR ₃ ) ₂ / BF ₃ OEt ₂ (where n = 1 , 2; L = PR ₃ or ethylene; R = Ph, OC ₆ H ₄ CH ₃ -o) in combination with controlled amounts of water as a modifying component and the process is carried out in an organic solvent, for example toluene, with a molar ratio of boron to nickel, B: Ni = 50: 1-600: 1, ratio H ₂ O / Ni = 2-104, temperature 10-80 ° C.

It is proposed to use catalysts based on novalent nickel compounds in combination with boron trifluoride etherate and controlled amounts of water.

A distinctive feature of the present invention is the use of catalytic systems based on zero-valent nickel complexes of the general formula (L) _n Ni (PR ₃ ) ₂ (where n = 1, 2; L = PR ₃ or ethylene; R = Ph, OS ₆ H ₄ CH ₃ -o), water and boron trifluoride etherate of the formula BF ₃ OEt ₂ .

The method is as follows.

The method consists in reacting a nickel compound, water and boron trifluoride etherate in an organic solvent, for example toluene. The components are mixed in the following order: the required amount of water is introduced into the solution of norbornene in an organic solvent using a microsyringe, a solution of nickel compound (0) of the general formula (L) _n Ni (PR ₃ ) ₂ (where n = 1, 2; L = PR ₃ or ethylene; R = Ph, OC ₆ H ₄ CH ₃ -o) in an organic solvent; boron trifluoride etherate is then introduced. Optimum process conditions: molar ratio of boron to nickel, B: Ni = 50: 1-600: 1, preferably B: Ni = 200: 1-400: 1, ratio H ₂ O / Ni = 2-104, preferably 6-25 , temperature 10-80 ° C, preferably 25 ° C.

Norbornene and toluene are first dehydrated and degassed by boiling and subsequent distillation over sodium in the presence of benzophenone in an argon atmosphere.

The characteristic viscosity of the polymers is determined at 25 ° C, the solvent is 1,2,4-trichlorobenzene.

The additive nature of the structure of the resulting polynorbornene is confirmed by NMR and IR spectroscopy. In the ¹ H NMR spectrum there are no bands from protons of double bonds. The IR spectrum of polymer samples contains characteristic absorption bands: 2946.95, 2867.12, 1474.04, 1452.52, 1363.38, 1294.36, 1257.71, 1220.05, 1145.55, 1108.23, 978.32, 940.01, 890.81, 813.40 and 774.15 cm ^-1 . Strong absorption bands in the region of 1452-1474 cm ^-1 from δ _HCH deformation vibrations of bridging CH ₂ groups of the norbornene ring are a sign of additive 2,3 polymerization.

The following examples illustrate the present invention.

Example 1

A solution of norbornene in toluene (80% mol.) Containing 4.71 g (0.05 mol) of norbornene, the required amount of toluene (up to 10 ml of the total volume of the reaction mixture) was loaded into a 20 ml flask pre-evacuated and filled with an inert gas (argon) with a magnetic stirrer. a calculated amount of water was added with a microsyringe, which, taking into account the trace amounts of water in the solvent and norbornene, determined by the Fisher method, was 9 · 10 ^-5 mol H ₂ O, a solution of Ni (PPh ₃ ) ₄ in toluene containing 1 · 10 ^-5 mol Ni. The polymerization was initiated by the introduction of BF ₃ OEt ₂ (4 · 10 ^-3 mol). The molar ratio of NB: B: Ni = 5000: 400: 1. The reaction time was 30 minutes. The reaction was interrupted by the addition of acidified (HCl, 3% wt.) Ethanol, the precipitated polymer was washed with ethanol three times and dried in vacuum (10 mmHg) at 80 ° C for 6 h. The polymer yield was 3.00 g or 6383 mol of polynorbornene per mole of Ni per hour. The intrinsic viscosity in 1,2,4-trichlorobenzene at 25 ° C was 0.591 dL / g.

Examples 2-8.

These examples illustrate the effect of the H ₂ O: Ni ratio on the yield and intrinsic viscosity of polynorbornene. The reactions were carried out analogously to example 1. The results of the experiments are combined in Table 1.

Table 1 Norbornene polymerization. System Ni (PPh ₃ ) ₄ + nH ₂ O + 400BF ₃ OEt ₂ (NB / Ni = 5000. Reaction time 30 minutes. The amount of Ni - 1 · 10 ^-5 mol. T = 25 ° C. The solvent is toluene. Total volume mixtures -10 ml) Example No. H ₂ O / Ni Yield, g Revolutions, mol NB / mol Ni per hour [η] dl / g Conversion% 2 2 * 0.15 319 - 3 3 four 0.7 1489 0.953 fifteen four fourteen 3,343 7113 0.443 71 5 19 3.85 8191 0.424 82 6 29th 4.1 8723 0.449 87 7 54 3.95 8404 0.254 84 8 104 3,5 7447 0.226 74 * - the sample is poorly soluble in 1,2,4-trichlorobenzene

Examples 9-15.

These examples illustrate the effect of the composition of complexes of novalent nickel and the ratio B / Ni on the yield and intrinsic viscosity of polynorbornene. The polymerization was carried out analogously to example 1, the results of the experiments are presented in Tables 2 and 3.

table 2 Norbornene polymerization. System (CH ₂ = CH ₂ ) Ni (PPh ₃ ) ₂ + 6H ₂ O + nBF ₃ OEt ₂ (Amount Ni - 1 · 10 ^-5 mol. T = 25 ° C. Solvent - toluene. Total mixture volume - 10 ml ) Example No. B / ni Yield, g Revolutions, mol NB / mol Ni per hour [η], dl / g Conversion% τ min 9 25 - - - - thirty 10 fifty one 2128 0.24 21 thirty eleven one hundred 1.3 2766 0.32 28 thirty 12 200 3 19149 0.41 64 10 13 400 0.8 1702 0.77 17 thirty

Table 3 Norbornene polymerization on the system (CH ₂ = CH ₂ ) Ni (PR ₃ ) ₂ + 3H ₂ O + 400BF ₃ OEt ₂ NB / Ni = 3250. The reaction time is 30 minutes. The amount of Ni is 1.2 · 10 ^-5 mol. t = 25 ° C. The solvent is toluene. The total volume of the mixture is 6 ml. Example No. PR ₃ Revolutions, mol NB / mol Ni per hour Conversion% Yield, g fourteen PPh ₃ 1590 24 0.9 fifteen P (OC ₆ H ₄ CH ₃ -o) ₃ 654 10 0.37

Compared with known methods, the efficiency of the norbornene polymerization process is increased.

Claims (1)

A method of producing a catalyst for the additive polymerization of norbornene based on complexes of non-valent nickel and BF ₃ OEt ₂ , characterized in that the process uses catalytic systems of the composition (L) _n Ni (PR ₃ ) ₂ / BF ₃ OEt ₂ , where n = 1, 2 ; L is PR ₃ or ethylene; R - Ph, OS ₆ Н ₄ СН ₃ -о), in combination with controlled amounts of water as a modifying component, and the process is carried out in an organic solvent, for example toluene, at a molar ratio of boron and nickel B: Ni = 50: 1-600: 1, the ratio of H ₂ O / Ni = 2-104, temperature 10-80 ° C.