Nitrogen phosphorus compounds and their use for the preparation of high / ultra high molecular weight polyisobutylenes

Abstract

The application relates to a nitrogen-phosphorus compound and its application in the preparation of high / super high molecular weight polyisobutylene, and belongs to the field of high molecular compound preparation. The nitrogen-phosphorus compound is provided, and its structural general formula (I) is as follows: wherein R1-R5 represent groups as described in the claim and the specification. The nitrogen-phosphorus compound is used for preparing high / super high molecular weight polyisobutylene, and the preparation method comprises the following steps: under the catalysis of a three-component composite catalyst, isobutene solution is subjected to slurry polymerization reaction at-90 DEG C to-30 DEG C to obtain high / super high molecular weight polyisobutylene; the three-component composite catalyst comprises a main initiator, a co-initiator and the nitrogen-phosphorus compound. The addition of the nitrogen-phosphorus compound can make the weight average molecular weight of the obtained polyisobutylene reach 9500000 g / mol, and the molecular weight distribution is narrow.

Description

Technical Field

[0001] This invention belongs to the field of polymer compound preparation, and more specifically, it relates to a nitrogen-phosphorus compound and its application in the preparation of high / ultra-high molecular weight polyisobutylene. Background Technology

[0002] Polyisobutylene (PIB) is classified by molecular weight into low molecular weight PIB, medium molecular weight PIB, high molecular weight PIB, and ultra-high molecular weight PIB. Low molecular weight PIB has a weight-average molecular weight (Mw) of less than 10,000; medium molecular weight PIB has a weight-average molecular weight (Mw) of more than 10,000 but less than 100,000; high molecular weight PIB has a weight-average molecular weight (Mw) of more than 100,000 but less than 600,000; and ultra-high molecular weight PIB has a weight-average molecular weight (Mw) of more than 600,000. High / ultra-high molecular weight PIBs possess various excellent properties due to their fully saturated polymer backbone and the presence of two side methyl groups in the polymer monomer units, such as thermal stability, UV resistance, weather resistance, and high barrier properties against water and oxygen. They are mainly used in sealing materials, rubber products, anti-corrosion linings, waterproof membranes, insulating materials, energy-absorbing materials, and radiation-shielding materials, and are particularly useful in high-end fields such as aerospace and weaponry. High / ultra-high molecular weight polyisobutylene, as an important strategic material, plays an extremely important role in the fields of national defense, aerospace, and medical devices. It also has irreplaceable advantages in fields such as gas sealing and damping vibration reduction. Moreover, the preparation technology of high molecular weight and ultra-high molecular weight polyisobutylene is still a blank in the domestic market.

[0003] Obtaining high / ultra-high molecular weight polyisobutylene typically requires very low polymerization temperatures, such as the BASF belt process. In this process, liquid isobutylene, along with boron trifluoride as a polymer catalyst and excess liquid ethylene, is passed through a continuous steel belt 50 to 60 cm wide. This belt is guided into a groove shape and placed within an airtight cylindrical enclosure. Constant evaporation of ethylene at standard pressure sets the temperature at -104°C. This effectively removes the heat of polymerization. Another commonly used method for preparing higher molecular weight polyisobutylene is the Exxon slurry process, where the polymerization reaction is carried out at -80 to -85°C in a stirred tank filled with liquid ethylene and equipped with a cooling jacket. The catalyst used is a solution of anhydrous aluminum chloride dissolved in methyl chloride. BASF recently published a patent (CN104136470A) disclosing a method for polymerizing isobutylene in C1-C8 hydrocarbons or halogenated hydrocarbons at -80°C to -190°C using a Lewis acid cationic polymerization catalyst, by adding a reaction promoter of an olefinically unsaturated oxygen-containing hydrocarbon compound and a chain length regulator containing at least one tertiary olefin carbon atom. This method can produce polyisobutylene with a weight average molecular weight of 75,000 to 10,000,000. However, this reaction requires polymerization at extremely low temperatures, resulting in high energy consumption. Therefore, it is essential to find a low-energy, simple, and efficient preparation method. Summary of the Invention

[0004] To address the problem that existing technologies for preparing high / ultra-high molecular weight polyisobutylene require precise control of the polymerization temperature at extremely low temperatures, this invention provides a nitrogen-phosphorus compound and its application in the preparation of high / ultra-high molecular weight polyisobutylene. This invention provides a novel nitrogen-phosphorus compound, and by adding this compound to the cationic polymerization catalyst during the preparation of high / ultra-high molecular weight polyisobutylene, the polymerization reaction can be effectively stabilized without controlling the polymerization temperature at extremely low temperatures. This simple and effective method achieves the synthesis of high / ultra-high molecular weight polyisobutylene, offering advantages of simplicity, effectiveness, and high economic benefits for polyisobutylene preparation.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a nitrogen-phosphorus compound with the following general structural formula:

[0007]

[0008] R1-R5 are individually represented as hydrogen, alkyl with 1-40 carbon atoms, aryl with 6-40 carbon atoms, or substituted aryl with 6-40 carbon atoms.

[0009] The application of the nitrogen and phosphorus compounds of the present invention in the preparation of high / ultra-high molecular weight polyisobutylene, specifically, provides a method for preparing high / ultra-high molecular weight polyisobutylene.

[0010] The present invention provides a method for preparing high / ultra-high molecular weight polyisobutylene, wherein the catalyst used in the cationic polymerization process includes the above-mentioned nitrogen and phosphorus compounds.

[0011] Furthermore, the molar ratio of isobutylene to nitrogen and phosphorus compounds is (500–10000):1.

[0012] The preparation method of the high / ultra-high molecular weight polyisobutylene includes the following steps: under the catalysis of a three-component composite catalyst, the isobutylene solution undergoes a slurry polymerization reaction at -90℃ to -30℃ to obtain high / ultra-high molecular weight polyisobutylene.

[0013] Even at the same temperature, the method for preparing high / ultra-high molecular weight polyisobutylene used in this invention can obtain polyisobutylene with even higher molecular weight.

[0014] By controlling the polymerization temperature and the amount of nitrogen and phosphorus compounds, high molecular weight polyisobutylene or ultra-high molecular weight polyisobutylene can be obtained respectively.

[0015] Furthermore, one or more C1 to C8 hydrocarbons or one or more halogenated C1 to C8 hydrocarbons or mixtures thereof are used as inert solvents in the isobutylene solution. The mass fraction of the isobutylene solution is 10 wt% to 45 wt%.

[0016] Furthermore, the three-component composite catalyst comprises a main initiator, a co-initiator, and a nitrogen-phosphorus compound; wherein the molar ratio of the co-initiator to the main initiator is (1-50):1; and the molar ratio of the nitrogen-phosphorus compound to the co-initiator is 1:(0.1-5).

[0017] More preferably, the three-component composite catalyst is prepared by first mixing the co-initiator and the nitrogen and phosphorus compound at low temperature; then adding the main initiator during polymerization.

[0018] The main initiator is selected from one or more of water, hydrogen chloride gas, tert-butanol, benzyl chloride, 2-chloro-2,4,4-trimethylpentane, cumyl chloride, dicumyl chloride, 5-tert-butyl-1,3-dicumyl chloride, and 5-tert-butyl-1,3-bis(1-methyl-1-methoxyethyl)benzene.

[0019] The co-initiator is a Lewis acid co-initiator, selected from one or more of titanium tetrachloride, ferric chloride, boron trifluoride, boron trichloride, gallium trichloride, aluminum chloride, and alkyl aluminum chloride.

[0020] Furthermore, the alkyl aluminum chloride is selected from one or more of dichloroethylaluminum, trichlorotriethylaluminum, dichlorodiethylaluminum, and dichloroisobutylaluminum.

[0021] The above-described method for preparing high / ultra-high molecular weight polyisobutylene provides a simple and economical way to obtain high / ultra-high molecular weight polyisobutylene with a weight-average molecular weight of 300,000 g / mol to 9,500,000 g / mol, while maintaining a good molecular weight distribution (M). w / M n (In the range of 1.3-3.5)

[0022] In summary, the present invention has the following beneficial effects:

[0023] (1) The present invention provides a novel nitrogen-phosphorus compound, which has a simple synthesis method.

[0024] (2) Since the present invention only adds nitrogen and phosphorus compounds as stabilizers to the cationic polymerization system, it is not necessary to precisely control the polymerization temperature at extremely low temperatures. The preparation method is simple and economically efficient. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 The nitrogen-phosphorus compound 4-benzyl-2-(diphenylphosphino)-N,N-dimethylnaphthalene-1-amine obtained in Example 1 of this invention was prepared according to the present invention. 1 H-NMR and 13 C-NMR;

[0027] in, Figure 1 (a) is 1 H NMR, 400MHz, CDCl3; Figure 1 (b) is 13 C{ 1 H NMR, 101MHz, CDCl3.

[0028] Figure 2 The GPC curve of polyisobutylene prepared in Example 1 of this invention is shown.

[0029] Figure 3 The GPC curve of polyisobutylene prepared in Comparative Example 1 of this invention is shown.

[0030] Figure 4 The GPC curve of polyisobutylene prepared in Comparative Example 2 of this invention is shown.

[0031] Figure 5 The GPC curve of polyisobutylene prepared in Example 3 of this invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with comparative examples, embodiments, and corresponding drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Unless otherwise specified, the reagents or instruments used in the following examples are all commercially available products.

[0034] Preparation Example

[0035] Preparation of nitrogen and phosphorus compounds Example 1

[0036] Preparation of 4-benzyl-2-(diphenylphosphino)-N,N-dimethylnaphthalene-1-amine

[0037]

[0038] The 25 mL Schlenk reactor equipped with a magnetic stirrer was purged three times under vacuum / nitrogen. Then, under a nitrogen atmosphere, 1-[chloro(phenyl)methyl]naphthalene (1a, 1.011 g, 4.0 mmol), Pd(PPh3)4 (0.2267 g, 5 mol%), and NaO were added sequentially. t Bu (1.536 g, 16 mmol, 4.0 equiv.) was added to the reactor using a 100 μL microsyringe, followed by the addition of 66.67 μL of H2O. Finally, DMF (0.9232 mL, 1.2 mmol, 3.0 equiv.) and anhydrous 2-MeTHF (40.0 mL) were added using 1 mL and 5 mL syringes, respectively. The reaction was carried out at 80 °C for 2 h. Thin-layer chromatography (TLC) confirmed the complete consumption of 1a, indicating the end of the reaction. After the reactor returned to room temperature, 10 mL of H2O was added to quench the reaction mixture. The reaction solution was then extracted with ethyl acetate (10 mL × 3). The combined organic phases were washed with saturated brine (10 mL × 3), dried over anhydrous sodium sulfate, and filtered. The solvent was removed by rotary evaporation, and the product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 100:1) to obtain (2a, 768.0 mg, yield 76%).

[0039] To a 25 mL round-bottom flask equipped with a magnetic stirrer, 2a (78.3 mg, 0.3 mmol), NBS (58.8 mg, 0.33 mmol, 1.1 equiv.), silica gel (72.0 mg, 1.2 mmol, 4.0 equiv.), and CCl4 (3.0 mL) were added sequentially. The flask was transferred to an oil bath at 30 °C and heated with stirring for 2 h until the reaction was complete. The reaction mixture was filtered through a sintered glass funnel to remove insoluble substances, washed with sodium thiosulfate water, dried over anhydrous Na2SO4, and filtered again. The solvent was removed by rotary evaporation, and the mixture was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 50:1) to give the corresponding brominated product 2ab (65.1 mg, yield 64%).

[0040] Subsequently, 2ab (0.5 mmol, 169.5 mg) was added to a 100 mL three-necked round-bottom flask equipped with a magnetic stirrer. After three purgings under vacuum / nitrogen, anhydrous tetrahydrofuran (10 mL) was added under a nitrogen atmosphere. The three-necked round-bottom flask was transferred to a liquid nitrogen / ethanol bath to cool the reaction solution to -78 °C. Then, n-butyllithium (0.25 mL, 0.55 mmol, 2.5 M inn-hexane) was added dropwise to the reaction solution through a constant-pressure dropping funnel. After the addition was complete, the reaction solution was stirred at -78 °C for 1 h. Subsequently, diphenylphosphine chloride (97.0 mL, 5.5 mmol, 1.1 equiv.) was slowly added dropwise to the reaction solution using a 100 μL microsyringe. After the addition was complete, the reaction solution was gradually heated to room temperature and stirred overnight at room temperature. After the reaction was complete, the solvent was removed by rotary evaporation, and the phosphine ligand 2ac (123.6 mg, yield 56%) was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 50:1). The prepared 2ac was analyzed by NMR, and its 1H NMR spectrum is shown below. Figure 1 (a), carbon spectrum see Figure 1 (b) specifically refers to: 1 H NMR (400MHz, CDCl3) δ7.98 (dd, J=19.4, 8.1Hz, 2H), 7.44–7.36 (m, 2H), 7.31–7.25 (m, 10H), 7.12 (dd,J=19.4,7.1Hz,3H),7.02(d,J=7.4Hz,2H),6.78(d,J=3.1Hz,1H),4.21(s,2H),2.84(s,6H). 13 C NMR (101MHz, CDCl3) δ152.2,152.0,140.5,138.9,138.8,135.9,134.8,134.2,134.1,133.9,132.7,131.4, 128.7,128.6,128.5,128.4,126.3,126.1,125.6,125.5,125.1,125.0,77.6,77.2,76.9,44.3,44.2,39.3. 31 P NMR (162MHz, CDCl3) δ-14.12.

[0041] Nitrogen and phosphorus compounds, example 2

[0042] 4-Benzyl-2-(dimethylphosphino)-N,N-dimethylnaphthalene-1-amine

[0043]

[0044] 1H NMR (400MHz, CDCl3) δ7.91–7.84(m,1H),7.82–7.75(m,1H),7.68–7.59(m,1H),7.51–7.43(m ,1H),7.31–7.17(m,2H),7.17–7.09(m,2H),4.25(t,J=1.0Hz,1H),2.93(s,4H),1.65(s,4H). 13 C NMR (101MHz, CDCl3) δ 145.3 (d, J = 16.0Hz), 139.1, 138.2 (d, J = 21.0Hz), 137.1 (d, J = 6.1Hz), 132.7 (d, J = 3.0Hz), 129.0, 128. 7,128.7(d,J=6.0Hz),127.7,127.2,127.2(d,J=16.0Hz),127.0,126.5,124.7(d,J=3.0Hz),42.7,37.8,15.6(d,J=23.0Hz).

[0045] Nitrogen and phosphorus compounds 3

[0046] 2-(Dimethylphosphino)-N,N-dimethylnaphthyl-1-amine

[0047]

[0048] 1 H NMR (400MHz, CDCl3) δ8.24–8.17(m,1H),7.91–7.80(m,1H),7.71–7.57(m,2H),7.56–7.49(m,1H),7.44–7.38(m,1H),2.93(s,6H),1.64(s,6H). 13 C NMR (101MHz, CDCl3) δ 145.9 (d, J = 16.0Hz), 137.3 (d, J = 21.0Hz), 135.4 (d, J = 3.0Hz), 128. 4,128.3,128.1,127.1,126.6(d,J=6.0Hz),124.5(d,J=3.0Hz),42.7,15.6(d,J=23.0Hz).

[0049] Nitrogen and phosphorus compounds 4

[0050] 4-Benzyl-N,N-di-tert-butyl-2-(diphenylphosphino)naphthyl-1-amine

[0051]

[0052] 1H NMR (400MHz, CDCl3) δ8.21–8.14(m,1H),7.90–7.85(m,1H),7.67–7.60(m,1H),7.50–7.44(m, 1H),7.30–7.18(m,3H),7.17–7.11(m,3H),4.25(s,2H),1.64(d,J=2.0Hz,6H),1.35(s,18H). 13 C NMR (101MHz, CDCl3) δ 143.8 (d, J = 16.0Hz), 139.1, 137.9 (d, J = 21.0Hz), 137.1 (d, J = 6.1Hz), 133.6 (d, J = 3.0Hz), 129. 0,128.7,127.7,127.7(d,J=16.0Hz),127.2,127.0,126.5,125.1(d,J=3.0Hz),54.9,37.8,30.0,15.6(d,J=23.1Hz).

[0053] Comparison of nitrogen compounds 5

[0054] 4-Benzyl-N,N-dimethylnaphthyl-1-amine

[0055]

[0056] 1 H NMR (400MHz, CDCl3) δ8.28 (dd, J=8.3, 1.6Hz, 1H), 7.92 (dd, J=8.2, 1.5Hz, 1H), 7.4 6–7.37(m,2H),7.25–7.09(m,6H),6.97(d,J=7.6Hz,1H),4.33(s,2H),2.83(s,6H). 13 C NMR (101MHz, CDCl3) δ150.1,141.1,133.3,131.3,129.3,128.8,128.6,128.5, 127.3,126.1,125.9,125.0,124.9,124.8,113.8,77.5,77.2,76.8,45.5,38.9.

[0057] Example

[0058] Example 1:

[0059] 1) Co-initiator formulation

[0060] The co-initiator preparation bottle containing 0.045g of anhydrous aluminum trichloride was placed in a -30℃ cold bath. After cooling, 5g of chloromethane was added and stirred to dissolve. At -30℃, 0.075g of the nitrogen-phosphorus compound 4-benzyl-2-(diphenylphosphino)-N,N-dimethylnaphthalene-1-amine (the molar ratio of aluminum trichloride to nitrogen-phosphorus compound was 1 / 2) was added to the co-initiator preparation bottle and mixed evenly to obtain the polymerization co-initiator solution.

[0061] 2) Isobutylene polymerization

[0062] A polymerization flask purged with dry nitrogen was placed in a -90°C cold bath under nitrogen protection. 47 g of isobutylene and 141 g of chloromethane were added to prepare an isobutylene solution (isobutylene mass percentage concentration: 25 wt%). Then, 0.61 mg of water (water to aluminum trichloride molar ratio: 1 / 10) was added to the isobutylene solution. While stirring, a prepared co-initiator solution (isobutylene monomer to nitrogen-phosphorus compound molar ratio: 5000) was added to the polymerization flask. After reacting for 30 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the mixture was introduced into a separatory funnel to remove the aqueous phase. The polymer solution was filtered, distilled to remove the solvent, and dried in a vacuum oven at 40°C for 6 hours until constant weight, yielding 46.06 g of polymer, with a polymer yield of 98.0%. GPC analysis was performed (see...). Figure 2 ), polymer weight-average molecular weight (M w The molecular weight is 9.5 million, and the molecular weight distribution (M) is... w / M n The value is 2.10.

[0063] Comparative Example 1:

[0064] The difference from Example 1 is that no nitrogen and phosphorus compounds were added.

[0065] 1) Co-initiator formulation

[0066] The initiator preparation bottle containing 0.045g of anhydrous aluminum trichloride was placed in a -30℃ cold bath. After cooling, 2g of chloromethane was added and stirred to dissolve, thus obtaining the polymerization initiator solution.

[0067] 2) Isobutylene polymerization

[0068] A nitrogen-purged polymerization flask was placed in a -90°C cold bath under nitrogen protection. 47 g of isobutylene and 141 g of chloromethane were added to prepare an isobutylene solution (isobutylene concentration 25 wt%). Then, 0.61 mg of water (water to aluminum trichloride molar ratio 1 / 10) was added to the isobutylene solution. The prepared co-initiator solution was added to the polymerization flask with stirring. After reacting for 30 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the aqueous phase was removed by introducing the mixture into a separatory funnel. The polymer solution was filtered, distilled to remove the solvent, and dried in a vacuum oven at 40°C for 6 hours to constant weight, yielding 42.3 g of polymer, with a polymer yield of 90%. GPC analysis was performed (see...). Figure 3 ), polymer weight-average molecular weight (M w The molecular weight is 2 million, and the molecular weight distribution (M) is... w / M n The value is 4.1. This comparative example and Example 1 illustrate that, using the embodiments of the present invention, higher molecular weight polyisobutylene can be prepared at the same temperature, or polymers can be prepared without lower temperatures, resulting in greater energy savings.

[0069] Comparative Example 2:

[0070] The difference from Example 1 is that no nitrogen or phosphorus compound was added, but a nitrogen compound 4-benzyl-N,N-dimethylnaphthalene-1-amine was added.

[0071] 1) Co-initiator formulation

[0072] The initiator preparation bottle containing 0.045g of anhydrous aluminum trichloride was placed in a -30℃ cold bath. After cooling, 2g of chloromethane was added and stirred to dissolve. At -30℃, 0.044g of nitrogen compound 4-benzyl-N,N-dimethylnaphthalene-1-amine (the molar ratio of aluminum trichloride to nitrogen compound was 1 / 2) was added to the co-initiator preparation bottle and mixed evenly to obtain the polymerization co-initiator solution.

[0073] 2) Isobutylene polymerization

[0074] A polymerization flask purged with dry nitrogen was placed in a -90°C cold bath under nitrogen protection. 47 g of isobutylene and 141 g of chloromethane were added to prepare an isobutylene solution (isobutylene mass percentage concentration: 25 wt%). Then, 0.61 mg of water (molar ratio of water to aluminum trichloride: 1 / 10) was added to the isobutylene solution. While stirring, a prepared co-initiator solution (molar ratio of isobutylene monomer to nitrogen compound: 5000) was added to the polymerization flask. After reacting for 30 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the aqueous phase was removed by introducing the mixture into a separatory funnel. The polymer solution was filtered, the solvent was removed by distillation, and the solution was dried in a vacuum oven at 40°C for 6 hours until constant weight, yielding 43.2 g of polymer, with a polymer yield of 92.0%. GPC analysis was performed (see...). Figure 4 ), polymer weight-average molecular weight (M w The molecular weight is 3 million, and the molecular weight distribution (M) is... w / M n The value is 2.4.

[0075] Reference manual attached Figure 2 , 3 4. As can be seen from the comparison between Example 1 and Comparative Examples 1-2, using the initiator system proposed by the inventors, ultra-high molecular weight polyisobutylene with a narrow molecular weight distribution is obtained.

[0076] Example 2

[0077] 1) Initiator preparation

[0078] The preparation bottle containing 0.057g of benzyl chloride as the main initiator was placed in a -30℃ cold bath. After cooling, 5g of n-hexane was added and stirred to dissolve. At -30℃, 0.109g of diethylaluminum chloride (the molar ratio of co-initiator to main initiator was 2:1) and 0.058g of nitrogen-phosphorus compound 4-benzyl-2-(dimethylphosphino)-N,N-dimethylnaphthalene-1-amine (the molar ratio of diethylaluminum chloride to nitrogen-phosphorus compound was 5 / 1) were added to the preparation bottle of the main initiator. After mixing evenly, the mixture was stirred and reacted for 30 minutes to obtain the polymerization initiator solution.

[0079] 2) Isobutylene polymerization

[0080] A polymerization flask purged with dry nitrogen was placed in a -30°C cold bath under nitrogen protection. 10 g of isobutylene and 90 g of n-hexane were added to prepare an isobutylene solution (isobutylene mass percentage concentration: 10 wt%). While stirring, a prepared initiator solution (molar ratio of isobutylene monomer to nitrogen-phosphorus compound: 1000) was added to the polymerization flask. After reacting for 60 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the aqueous phase was removed by introducing the mixture into a separatory funnel. The polymer solution was filtered, the solvent was removed by distillation, and the solution was dried in a vacuum oven at 40°C for 6 hours until constant weight, yielding 9 g of polymer, with a polymer yield of 90%. GPC analysis showed that the polymer weight-average molecular weight (Mg) was... w The molecular weight is 300,000, and the molecular weight distribution (M) is... w / M n The value is 2.2.

[0081] Example 3

[0082] 1) Initiator preparation

[0083] A co-initiator preparation bottle containing 0.040 g of anhydrous titanium tetrachloride was placed in a -30°C cold bath. After cooling, 5 g of chloromethane was added and stirred to dissolve. At -30°C, 0.61 mg of 2-chloro-2,4,4-trimethylpentane (the molar ratio of co-initiator to main initiator was 50:1) and 0.75 g of 2-(diphenylphosphine)-N,N-dimethylnaphthalene-1-amine (the molar ratio of titanium tetrachloride to nitrogen and phosphorus compounds was 1 / 10) were added to the co-initiator preparation bottle and mixed thoroughly to obtain a polymerization initiator solution.

[0084] 2) Isobutylene polymerization

[0085] A polymerization flask purged with dry nitrogen was placed in a -40°C cold bath under nitrogen protection. 59 g of isobutylene and 72 g of dichloromethane were added to prepare an isobutylene solution (isobutylene mass percentage concentration: 45 wt%). While stirring, a prepared initiator solution (molar ratio of isobutylene monomer to nitrogen-phosphorus compound: 500) was added to the polymerization flask. After reacting for 60 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the aqueous phase was removed by introducing the mixture into a separatory funnel. The polymer solution was filtered, the solvent was removed by distillation, and the solution was dried in a vacuum oven at 40°C for 6 hours until constant weight, yielding 52.4 g of polymer, with a polymer yield of 88.9%. GPC analysis was performed (see...). Figure 5 ), polymer weight-average molecular weight (M w The molecular weight is 4.5 million, and the molecular weight distribution (M) is... w / M n The value is 2.90.

[0086] Example 4

[0087] 1) Initiator preparation

[0088] The preparation bottle containing 0.028 g of tert-butanol as the main initiator was placed in a -30°C cold bath. After cooling, 5 g of chloromethane was added and stirred to dissolve. At -30°C, 0.417 g of dichloroisobutylaluminum (the molar ratio of co-initiator to main initiator was 1 / 1) and 0.20 g of 4-benzyl-N,N-di-tert-butyl-2-(diphenylphosphino)naphth-1-amine (the molar ratio of dichloroisobutylaluminum to nitrogen and phosphorus compounds was 1 / 1) were added to the preparation bottle of the main initiator. After mixing evenly, the mixture was reacted for 20 minutes to obtain the polymerization initiator solution.

[0089] 2) Isobutylene polymerization

[0090] A polymerization flask purged with dry nitrogen was placed in a -60°C cold bath under nitrogen protection. 63 g of isobutylene and 147 g of chloromethane were added to prepare an isobutylene solution (isobutylene mass percentage concentration: 30 wt%). While stirring, a prepared initiator solution (molar ratio of isobutylene monomer to nitrogen-phosphorus compound: 3000) was added to the polymerization flask. After reacting for 60 minutes, the polymerization was terminated with a 1 wt.% sodium hydroxide ethanol solution. The mixture was washed with 300 mL of water, and the aqueous phase was removed by introducing the mixture into a separatory funnel. The polymer solution was filtered, the solvent was removed by distillation, and the solution was dried in a vacuum oven at 40°C for 6 hours until constant weight, yielding 57.3 g of polymer, with a polymer yield of 91.0%. GPC analysis showed that the polymer weight-average molecular weight (Mg) was... w The molecular weight is 1.5 million, and the molecular weight distribution (M) is... w / M n The value is 1.68.

[0091] As can be seen from Examples 2-4, the initiator systems in the inventive solutions within their scope can all produce high and ultra-high molecular weight polyisobutylene products with narrow molecular weight distribution.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing high / ultra-high molecular weight polyisobutylene, characterized in that, In the cationic polymerization process, under the catalysis of a three-component composite catalyst, isobutylene solution undergoes slurry polymerization at -90℃ to -30℃ to obtain high / ultra-high molecular weight polyisobutylene; the M of high / ultra-high molecular weight polyisobutylene... w The concentration ranges from 300,000 g / mol to 9,000,000 g / mol, with a molecular weight distribution in the range of 1.3-3.

5. The three-component composite catalyst comprises a main initiator, a co-initiator, and nitrogen and phosphorus compounds; The main initiator is selected from one or more of water, hydrogen chloride gas, tert-butanol, benzyl chloride, 2-chloro-2,4,4-trimethylpentane, cumyl chloride, dicumyl chloride, 5-tert-butyl-1,3-dicumyl chloride, and 5-tert-butyl-1,3-bis(1-methyl-1-methoxyethyl)benzene. The co-initiator is a Lewis acid co-initiator, selected from one or more of titanium tetrachloride, ferric chloride, boron trifluoride, boron trichloride, gallium trichloride, aluminum chloride, and alkyl aluminum chloride; The structural formulas of nitrogen and phosphorus compounds are as follows: .

2. The method for preparing high / ultra-high molecular weight polyisobutylene according to claim 1, characterized in that, The molar ratio of isobutylene to nitrogen and phosphorus compounds is (500–10000):

1.

3. The method for preparing high / ultra-high molecular weight polyisobutylene according to claim 1, characterized in that, The molar ratio of co-initiator to main initiator is (1-50):1; the molar ratio of nitrogen and phosphorus compound to co-initiator is 1:(0.1-5).

4. The method for preparing high / ultra-high molecular weight polyisobutylene according to claim 1, characterized in that, One or more C1 to C8 hydrocarbons or one or more halogenated C1 to C8 hydrocarbons or mixtures thereof are used as inert solvents in isobutylene solutions.

5. The method for preparing high / ultra-high molecular weight polyisobutylene according to claim 1, characterized in that, The mass fraction of the isobutylene solution is 10 wt% to 45 wt%.

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