CN1116320C - Catalyst for syndiotatic phenylethylene polymerization - Google Patents

Abstract

The invention relates to a catalyst for the syndiotactic polymerization of styrene, which mainly solves the problems of low catalytic activity and low content of syndiotactic polystyrene obtained when the catalyst made of titanocene compound is used in the styrene polymerization process in previous literatures . The present invention solves this problem well by adopting the technical scheme of forming a styrene syndiotactic polymerization catalyst with an indenyl metal titanium compound having a structural formula of IndTiCl ₂ (OR) and an alkyl aluminoxane, wherein Ind is an indenyl group, and can be used for In the industrial production of syndiotactic polymerization of styrene.

Description

Catalyst for Syndiotactic Polymerization of Styrene

technical field

The invention relates to a catalyst for syndiotactic polymerization of styrene.

Background technique

Polystyrene (Polystyrene, PS) obtained by free radical polymerization is a random polymer with hard quality, transparency, rigidity, electrical insulation, low price and easy dyeing. It has become one of the five general-purpose plastics today and is widely used. Used in packaging, construction, medicine, electronics, automobiles, daily necessities and other industries. However, due to the randomness of the structure, it is fragile, not heat-resistant, and not resistant to chemical corrosion.

European patent EP210615 introduced a polystyrene with high stereoregularity, in which the substitution of benzene rings is arranged in a syndiotactic structure. This crystalline material no longer has the disadvantages of random polymers, is almost insoluble in any organic solvent, and has a high melting point (250-280 ° C), heat resistance, chemical corrosion resistance, and its performance can be compared with polyester, polyamide and so on.

The catalytic system usually used for the syndiotactic polymerization of styrene consists of two parts, that is, transition metal organic compounds, especially Ti, Zr compounds, and methylaluminoxane (MAO) and B(C ₆ F ₅ ) ₃ as Representative cocatalyst.

Common catalysts in the literature include various halides of titanium, tetraalkoxy compounds (methoxyl, ethoxyl, propoxyl, isopropoxyl, etc.), metallocene compounds (titanium trichloride, trioxane Titanium, a trialkoxytitanium, and a variety of compounds substituted), titanium tetrahydrocarbyl and the corresponding zirconium compounds.

Since the 1950s, metallocene catalysts have been a research hotspot in catalyzing olefin polymerization. In the early 1980s, the discovery of Kaminsky cocatalyst methylaluminoxane promoted the catalytic polymerization of olefins into a new research climax. Among them, semi-sandwich compounds and formazan The catalytic system composed of aluminoxane and the like has remarkable syndiotropic and high catalytic activity for the catalytic polymerization of styrene monomers. Since then, patents involving various semi-sandwich compounds have appeared one after another.

European Patent EP0796875 (1997) (Process for the preparation of crystalline vinylomatic polymers with a dominant syndiotactic structure) discloses a class of indene-titanium catalysts with the following structural formula: Typical compound is Ind'TiCl ₃ ,

Ind'Ti(OR ¹ ) ₃ , Ind'Ti(R ² ) ₃ , (Ind'=4-methylindene, 4-ethylindene, 5-methylindene,

                                                                                                                                                                                                                       

R ¹ =Me, Et, Pr, Bu, Ph; R ² =Me, Et, ^iBu , Bz)

In the examples, the catalytic activity of this type of catalyst reaches 2.5×10 ⁶ g PS/(mole Ti·mole S·hour), and the syndiotacticity of the obtained polystyrene reaches 99.4%. However, the implementation of trialkoxy and trialkyl catalysts has not been reported. According to the literature, the synthesis of this type of compound is obtained by reacting the compound of trichloroindene titanium with the corresponding alcohol in the presence of triethylamine. The polarity of the raw material alcohol is similar to that of the product, so it is easy to mix with the product and difficult to obtain. Carry out separation and purification.

Contents of the invention

The object of the present invention is to provide a new catalyst for the syndiotactic polymerization of styrene in order to overcome the shortcoming that the catalyst made of metallocene compounds introduced in the previous literature has a low catalytic effect when used in the styrene syndiotactic polymerization process. When the catalyst is used in the syndiotactic polymerization process of styrene, it has the characteristics of high catalytic activity, good catalytic effect, high content of syndiotactic polystyrene obtained, and high melting point of the obtained polymer.

The purpose of the present invention is achieved by the following technical solutions: a catalyst for syndiotactic polymerization of styrene comprises the following active components:

a) IndTiCl ₂ (OR);

b) alkylaluminoxanes;

Wherein: Ind is indenyl;

R is an alkyl group with a straight chain, branched chain or cyclic structure of 3 to 6 carbon atoms;

In terms of molar ratio, alkylaluminoxane/IndTiCl ₂ (OR) is 300-4100.

In the above technical solutions, the preferred solution of alkylaluminoxane is methylaluminoxane, and the preferred range of alkylaluminoxane/IndTiCl ₂ (OR) is 300-2100 in terms of molar ratio.

The catalyst of the present invention can be prepared by general mixing.

The invention adopts a novel indenyl titanium compound and an alkyl aluminoxane to form a catalyst, which is a high-efficiency syndiotactic polymerization catalyst for styrene monomers. When used in the syndiotactic polymerization of styrene, the activity of the catalyst can reach up to 1.39×10 ⁷ g PS/mole Ti·mol S·hour, the syndiotactic weight content of the polystyrene obtained by catalysis can reach up to 99.6%, and the melting point of the polymer is 273 ~277°C, good results have been achieved.

Detailed ways

The present invention will be further elaborated below by embodiment: 【Embodiment 1】

Polymerizations were carried out in a baked argon-filled ampule three times. 2 milliliters of styrene, 3.4 milliliters of toluene, 6.6 milliliters of methylalumoxane toluene solution with a concentration of 1.53 mol/liter, and 0.05 milliliters of 0.05 mol/liter compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule successively, and placed Polymerize for 1 hour in an oil bath whose temperature was previously adjusted to 50°C. Terminate the polymerization reaction with ethanol that is 10% HCl in terms of weight percentage. After filtering and washing, the resulting polymer is vacuum-dried at 80° C. for 24 hours to constant weight to obtain 0.1616 grams of polystyrene. The catalytic activity is 3.72×10 ⁶ g PS/(mole Ti·mole S·hour). Reflux in methyl ethyl ketone for 2 hours to remove atactic polystyrene, the measured weight content of syndiotactic polystyrene is 99.3%, and the melting point of the obtained polymer is 277°C. [Example 2]

2 milliliters of styrene, 3.4 milliliters of toluene, 6.6 milliliters of 1.53 mol/liter methylaluminoxane toluene solution, and 0.1 milliliter of 0.05 mol/liter compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule successively, wherein Me is a methyl group, placed in an oil bath with a constant temperature at 50°C and polymerized for 1 hour to obtain 0.1955 g of polystyrene, with a catalytic activity of 2.25×10 ⁶ g PS/(mole Ti·mol S·hour). The weight content of tactic polystyrene is 95.8%. [Example 3]

11 ml of styrene, 0.5 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.05 ml of toluene solution of 0.05 mol/L compound IndTiCl ₂ (OMe) were injected into the ampoule in sequence, and placed in a pre-constant temperature Polymerize in an oil bath at 50°C for 0.5 hours to obtain 1.5709 grams of polystyrene, with a catalytic activity of 1.31× ¹⁰⁷ grams of PS/(mole Ti mole S hour), and the measured syndiotactic polystyrene weight content is 90.1% . [Comparative Example 1]

11 ml of styrene, 0.5 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.05 ml of 0.05 mol/L IndTiCl ₃ in toluene solution were injected into the ampoule in sequence, and placed in a pre-heated to 50 ° C Polymerized in an oil bath for 0.5 hour to obtain 1.0996 g of polystyrene, with a catalytic activity of 9.19×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 86.4%. 【Example 4】

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule in sequence, and placed in a pre-heated Polymerize in an oil bath at 90° C. for 2 hours to obtain 1.8724 g of polystyrene, with a catalytic activity of 1.96×10 ⁶ g PS/(mole Ti mole S hour), and the measured syndiotactic polystyrene weight content is 87.7%. . 【Example 5】

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule in sequence, and placed in a pre-heated Polymerize in an oil bath at 70° C. for 1 hour to obtain 1.6544 grams of polystyrene, with a catalytic activity of 3.46×10 ⁶ grams of PS/(mole Ti mole S hour), and the measured syndiotactic polystyrene weight content is 90.3%. . 【Comparative example 2】

11 ml of styrene, 1 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L IndTiCl ₃ in toluene solution were injected into the ampoule in sequence, and placed in a pre-heated to 70°C Polymerized in an oil bath for 1 hour to obtain 1.4586 g of polystyrene, with a catalytic activity of 3.05×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 86.6%. [Example 6]

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule in sequence, and placed in a pre-heated Polymerize in an oil bath at 25° C. for 0.5 hour to obtain 0.9766 gram of polystyrene, the catalytic activity is 4.08×10 ⁶ gram PS/(mole Ti mole S hour), and the recorded syndiotactic polystyrene weight content is 85.2% . [Example 7]

2 milliliters of styrene, 8.5 milliliters of toluene, 1.6 milliliters of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.24 milliliters of 0.0025 mol/liter compound IndTiCl ₂ (OMe) in toluene were injected into the ampoule in sequence, and placed Polymerize for 1 hour in an oil bath with a constant temperature at 50°C in advance to obtain 0.1337 g of polystyrene, with a catalytic activity of 1.28× ¹⁰⁷ g PS/(mole Ti·mol S·hour), and the weight content of syndiotactic polystyrene was measured was 98.1%. [Embodiment 8]

(Preparation of Compound A): Under the protection of argon, slowly add the mixed solution of n-hexane and tetrahydrofuran (THF) in n-butyllithium in the n-hexane solution of alkanol (wherein R is ethyl) under the protection of argon. The molar ratio of base lithium is 1:1.2, the lithium salt solution generated by the reaction is cooled to -50°C, and the dichloromethane solution of IndTiCl ₃ with an equal molar number of alkyl alcohol is slowly added dropwise to the solution, and the drop is completed in 0.5 hours. Naturally raised to 30°C, stirred and reacted for 16 hours, filtered, and the clear liquid was sucked dry. The obtained solid was recrystallized with dichloromethane and n-hexane to obtain dark red crystals with a yield of 58%. The analysis test results are as follows

Molecular formula: C ₁₁ H ₁₂ Cl ₂ OTi; mass spectrum shows molecular ion peak 278 (5, M ⁺ ).

Infrared spectrum data (cm ^-1 ): 3300s, 1620m, 1460w, 1390w, 1050w, 880s, 825s.

NMR data ( ¹ H NMR, ppm): 7.79(dd, 2H, J=6.3Hz, J=3.0Hz), 7.45(dd, 2H, J=6.3Hz, J=3.0Hz), 6.84(d, 2H, J = 3.4 Hz), 6.80 (t, 1H, J = 3.4 Hz), 4.60 (q, 2H, J = 5.3 Hz), 1.31 (t, 3H, J = 5.3 Hz).

Elemental analysis data: measured, C: 47.21% H: 4.29%

Calculation, C: 47.36% H: 4.34% [Example 9]

(Preparation of Compound B): Under the protection of argon, the n-hexane solution of alkyl alcohol (wherein R is isopropyl) is slowly added dropwise to the n-hexane solution of n-butyl lithium, and the alkyl alcohol and butyl lithium The molar ratio of the lithium salt is 1:1, the lithium salt solution generated by the reaction is cooled to -60°C, and the dichloromethane solution of IndTiCl ₃ with a molar ratio of 1:1.2 to the alkyl alcohol is slowly added dropwise to the solution, and the drop is completed in 0.5 hours. , naturally rose to 35°C, stirred and reacted for 16 hours, filtered, and the clear liquid was sucked dry, and the obtained solid was recrystallized with dichloromethane and n-hexane to obtain dark red crystals with a yield of 76%. The analysis test results are as follows

Molecular formula: C ₁₂ H ₁₄ Cl ₂ OTi; mass spectrum shows molecular ion peak 292 (2, M ⁺ ).

Infrared spectrum data (cm ^-1 ): 3330s, 1613m, 1458w, 1392w, 1360w, 1315w, 1200w, 1168w, 1114w, 1050w, 884s, 768s.

NMR data ( ¹ H NMR, ppm): 7.80(dd, 2H, J=6.3Hz, J=3.1Hz), 7.45(dd, 2H, J=6.3Hz, J=3.1Hz), 6.82(d, 2H, J=3.4Hz), 6.78(t, 1H, J=3.4Hz), 4.92(m, 1H, J=6.1Hz), 1.38(d, 6H, J=6.1Hz).

Elemental analysis data: measured, C: 48.81% H: 4.76%

Calculation, C: 49.19% H: 4.82% [Example 10]

(Preparation of Compound C): Under the protection of argon, the n-hexane solution of alkyl alcohol (wherein R is cyclohexyl) is slowly added dropwise in the n-hexane solution of n-butyllithium, the mixture of alkyl alcohol and butyllithium The molar ratio is 1:1.1, the lithium salt solution generated by the reaction is cooled to -60°C, and the dichloromethane solution of _IndTiCl3 with an alkyl alcohol molar ratio of 1:1.2 is slowly added dropwise to the solution, and the drop is completed in 0.5 hours. Naturally raised to 30°C, stirred and reacted for 16 hours, filtered, and the clear liquid was sucked dry. The obtained solid was recrystallized with dichloromethane and n-hexane to obtain orange-red crystals with a yield of 61%. The analysis test results are as follows

Molecular formula: C ₁₅ H ₁₈ Cl ₂ OTi; mass spectrum shows molecular ion peak 332 (0.6, M ⁺ ).

Infrared spectrum data (cm ^-1 ): 3300s, 2930m, 2865m, 1615m, 1460w, 1398w, 1370w, 1055m, 1020w, 885s, 770s.

NMR data ( ¹ H NMR, ppm): 7.78 (dd, 2H, J=6.4Hz, J=3.0Hz), 7.41 (dd, 2H, J=6.4Hz, J=3.0Hz), 6.82 (d, 2H, J=3.4Hz), 6.79(t, 1H, J=3.4Hz), 4.70(m, 1H), 2.3~1.0(m, 10H).

Elemental analysis data: measured, C: 53.93% H: 5.35%

Calculation, C: 54.09% H: 5.45% [Example 11]

Polymerizations were carried out in a baked argon-filled ampule three times. 2 milliliters of styrene, 3.4 milliliters of toluene, 6.6 milliliters of 1.53 mol/liter methylalumoxane toluene solution, and 0.05 milliliter of 0.05 mol/liter compound A toluene solution were sequentially injected into the ampoule, and placed in a pre-heated to Polymerization was carried out in an oil bath at 50°C for 1 hour. Terminate the polymerization reaction with ethanol containing 10% HCl in weight concentration. After filtering and washing, the obtained polymer is vacuum-dried at 80°C for 24 hours to constant weight to obtain 0.2109 g of polystyrene with a catalytic activity of 4.85×10 ⁶ g PS/(mole Ti·mole S·hour). Reflux in methyl ethyl ketone for 2 hours to remove atactic polystyrene, the measured weight content of syndiotactic polystyrene is 99.6%, and the melting point of the obtained polymer is 275°C. [Example 12]

2 milliliters of styrene, 3.4 milliliters of toluene, 6.6 milliliters of 1.53 mol/liter methylalumoxane toluene solution, and 0.05 milliliter of 0.05 mol/liter compound B toluene solution were sequentially injected into the ampoule, and placed in a pre-heated to Polymerize in an oil bath at 50°C for 1 hour to obtain 0.1736 gram of polystyrene, the catalytic activity is 3.99×10 ⁶ gram PS/(mole Ti mole S hour), and the recorded syndiotactic polystyrene weight content is 99.1%. The melting point of the polymer was 273°C. [Example 13]

11 ml of styrene, 0.5 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.05 ml of 0.05 mol/L Compound A in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 50°C Polymerized in an oil bath for 0.5 hour to obtain 1.6676 g of polystyrene, the catalytic activity was 1.39×10 ⁷ g PS/(mole Ti·mol S·hour), and the measured weight content of syndiotactic polystyrene was 90.1%. [Comparative Example 3]

11 ml of styrene, 0.5 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.05 ml of 0.05 mol/L IndTiCl ₃ in toluene solution were injected into the ampoule in sequence, and placed in a pre-heated to 50 ° C Polymerized in an oil bath for 0.5 hour to obtain 1.0996 g of polystyrene, with a catalytic activity of 9.19×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 86.4%. [Example 14]

11 ml of styrene, 1 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L Compound A in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 50°C After polymerization in an oil bath for 0.5 hour, 1.5117 g of polystyrene was obtained, the catalytic activity was 6.32×10 ⁶ g PS/(mole Ti·mol S·hour), and the measured weight content of syndiotactic polystyrene was 88.4%. [Example 15]

11 ml of styrene, 1 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound A in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 70°C Polymerized in an oil bath for 1 hour to obtain 1.7452 g of polystyrene, with a catalytic activity of 3.65×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 91.2%. [Comparative Example 4]

11 ml of styrene, 1 ml of methylalumoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L IndTiCl ₃ in toluene solution were injected into the ampoule in sequence, and placed in a pre-heated to 70°C Polymerized in an oil bath for 1 hour to obtain 1.4586 g of polystyrene, with a catalytic activity of 3.05×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 86.6%. [Example 16]

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L Compound A in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 90°C Polymerized in an oil bath for 2 hours to obtain 2.2418 g of polystyrene, with a catalytic activity of 2.34×10 ⁶ g PS/(mol Ti·mol S·hour), and a measured syndiotactic polystyrene weight content of 90.7%. [Example 17]

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound A in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 25°C After polymerization in an oil bath for 0.5 hour, 0.9050 g of polystyrene was obtained, the catalytic activity was 3.78×10 ⁶ g PS/(mole Ti·mol S·hour), and the measured weight content of syndiotactic polystyrene was 83.1%. [Example 18]

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound B in toluene were injected into the ampoule in sequence, and placed in a pre-heated to 50°C After polymerization in an oil bath for 0.5 hour, 0.9711 g of polystyrene was obtained, the catalytic activity was 4.06×10 ⁶ g PS/(mole Ti·mol S·hour), and the measured weight content of syndiotactic polystyrene was 85.2%. [Example 19]

11 ml of styrene, 1 ml of methylaluminoxane toluene solution with a concentration of 1.53 mol/L, and 0.1 ml of 0.05 mol/L compound C in toluene were injected sequentially into the ampoule and placed in a pre-heated to 50°C After polymerization in an oil bath for 0.5 hour, 0.7794 g of polystyrene was obtained, the catalytic activity was 3.26×10 ⁶ g PS/(mole Ti·mol S·hour), and the measured weight content of syndiotactic polystyrene was 79.2%.

Claims (3)

1, a kind of catalyzer of syndiotactic polymerization of phenylethylene comprises following active constituent:

a)IndTiCl ₂(OR)；

B) alkylaluminoxane;

Wherein Ind is an indenyl;

R is the alkyl of straight chain, side chain or the ring texture of 3～6 carbon atoms;

With molar ratio computing, alkylaluminoxane/IndTiCl ₂(OR) be 300～4100.

2,, it is characterized in that alkylaluminoxane is a methylaluminoxane according to the catalyzer of the described syndiotactic polymerization of phenylethylene of claim 1.

3,, it is characterized in that with molar ratio computing alkylaluminoxane/IndTiCl according to the catalyzer of the described syndiotactic polymerization of phenylethylene of claim 1 ₂(OR) be 300～2100.