A process for the continuous polymerization of ethylene with alpha-olefins

Abstract

The application belongs to the technical field of olefin polymerization, and particularly relates to a method for continuous polymerization of ethylene and alpha-olefin. The feeding temperature of raw materials of the method is 10-30 DEG C; the temperature of polymerization reaction is 120-150 DEG C; the ratio of raw material heat removal amount to polymerization reaction heat exchange amount is Q, 50% < Q < 85%; Xc is the mass proportion of structural units from alpha-olefin monomers in the polymer, Tr is the temperature value of polymerization reaction in units of DEG C, Ta is the feeding temperature value of raw materials in units of DEG C, and W is the reaction solid content; W = polymer yield / total feeding amount * 100%; the total feeding amount includes the feeding amounts of raw materials, main catalysts and auxiliary catalysts. The method has low energy consumption, high polymerization activity, good flowability of the obtained polymer, no blocking of equipment, and is beneficial to long-term operation of the equipment and reduction of cost.

Description

Technical Field

[0001] This invention belongs to the field of olefin polymerization technology, specifically relating to a method for the continuous polymerization of ethylene and α-olefins. Background Technology

[0002] Polyolefin elastomers (POEs) are random copolymers of ethylene and 1-butene or 1-octene. Due to their lightweight, high transparency, high elasticity, aging resistance, and excellent electrical insulation properties, they are widely used in automotive plastic modification, photovoltaic films, footwear materials, cables, and packaging. The 1-butene or 1-octene content in the polyolefin elastomer chain segments is typically greater than 20 wt%, forming a uniform branched distribution. This disrupts the crystallinity of the ethylene segments, resulting in the elasticity, strength, and elastic recovery of rubber, while correspondingly reducing heat resistance indicators such as softening point and melting point. Therefore, slurry or vapor-phase processes generally cannot meet the production requirements of polyolefin elastomers, especially when the density of the polyolefin elastomer is below 0.88 g / cm³. 3 At that time, slurry or gas-phase polymerization processes are prone to clogging and wall adhesion, which affects the long-term high-quality and stable operation of the production unit.

[0003] Solution polymerization is the primary method for producing polyolefin elastomers. The copolymerization of ethylene with 1-butene or 1-octene is a strongly exothermic reaction. Effective heat exchange during polymerization to neutralize the heat of reaction and maintain constant reaction temperature parameters is crucial for ensuring stable production processes and product specifications. Low-temperature feedstock is a common heat exchange method in POE production. This involves using a low-temperature cold source to cool ethylene, 1-butene or 1-octene, and dispersant feedstock to a specific temperature before continuously feeding them into the reactor. Typically, the inlet feedstock needs to be cooled to below 0°C or even lower. The heat released during the reaction in the reactor is exchanged with the low-temperature feedstock to raise the temperature to the target reaction temperature, thus maintaining stable polymerization temperature conditions. Under these deheating conditions, the extremely low feedstock temperature widens the temperature difference between the feedstock and the reaction system, easily leading to a high-viscosity state and insufficient uniformity of the temperature field distribution, affecting the catalytic efficiency of the polymerization active centers. Furthermore, cooling the feedstock to low temperatures requires high-efficiency refrigeration equipment and a high-quality cold source, increasing energy costs. Meanwhile, under abnormal operating conditions where the polymerization reaction activity drops sharply, failure to adjust the low-temperature feedstock in time can easily cause a sudden drop in the temperature of the reaction system, which also increases the safety risk of polymer precipitation and blockage in the reactor. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of insufficient polymerization activity, high polymerization cost and blockage caused by low temperature feeding in the existing continuous polymerization methods of ethylene and α-olefins, thereby providing a method for continuous polymerization of ethylene and α-olefins.

[0005] Therefore, the present invention provides the following technical solution:

[0006] This invention protects a method for the continuous polymerization of ethylene and α-olefins, wherein the feed temperature of the raw materials is 10-30°C and the polymerization reaction temperature is 120-150°C;

[0007] The raw materials include ethylene monomers, α-olefin monomers, alkane solvents, and impurity removal agents; or...

[0008] The raw materials include ethylene monomer, α-olefin monomer, alkane solvent, impurity removal agent and hydrogen;

[0009] The ratio of the heat of material removal to the heat exchange of the polymerization reaction is Q, where 50% < Q < 85%.

[0010] ;

[0011] Where Xc is the mass percentage of structural units from α-olefin monomers in the polymer, Tr is the polymerization temperature in °C, Ta is the feed temperature in °C, and W is the reaction solids content.

[0012] W = Polymer yield / Total feed rate × 100%;

[0013] The total feed amount includes the feed amounts of raw materials, main catalyst, and co-catalyst.

[0014] The formula in this invention includes four variables: Xc, Tr, Ta, and W, forming a multi-parameter linkage control system. By precisely quantifying the dynamic balance between the heat released from the raw materials and the heat released during polymerization, the polymerization reaction is controlled. Tr and Ta are taken only as numerical values, without units, so the resulting Q is dimensionless. Because it is a continuous polymerization reaction, the calculation of W is based on the polymer yield and total feed rate per unit time interval after stable operation (polymerization temperature and raw material feed temperature remain constant; two consecutive temperature measurements with fluctuations <1℃ are considered stable).

[0015] In one optional embodiment, the method includes the following steps: mixing raw materials, adding a main catalyst and a co-catalyst, and carrying out a continuous polymerization reaction to obtain a polymer.

[0016] In this invention, the main catalyst and the co-catalyst are added to the reactor separately and simultaneously.

[0017] In this invention, after the continuous polymerization reaction, the process further includes a step of removing volatile components and a granulation step.

[0018] In one alternative embodiment, the α-olefin monomer includes at least one selected from propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, and 1-decene, and optionally includes 1-butene and / or 1-octene.

[0019] In one optional embodiment, the alkane solvent comprises C6-C... 10 Aliphatic hydrocarbons, C6-C 10 At least one of the aromatic solvents, optionally including C8-C4 solvents. 10 Mixed isoalkanes and / or n-hexane; alternatively, IsoparE (C8 content 70-80%, C9 content 20-30%, C20-30%). 10 The content is <10%) and / or industrial hexane (n-hexane ≥80%).

[0020] In one optional embodiment, the impurity remover includes at least one of methylaluminoxane and triisobutylaluminum, optionally triisobutylaluminum.

[0021] In an optional embodiment, the main catalyst comprises a group IVB-IIB transition metal compound. Optionally, the main catalyst comprises diphenylmethylene(cyclopentadienyl)(9-fluorenyl)zirconia dichloride, di-p-tolyl(cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconia dichloride, diphenylmethylene(cyclopentadienyl)(octamethyloctahydrobenzofluorenyl)zirconia dichloride, diphenylmethylene(3-tert-butyl-2-methylcyclopentadienyl)(fluorenyl)zirconia dichloride, bis(tetramethylcyclopentadienyl)hafnium dichloride, rac-ethylene-bis(indenyl)hafnium dichloride, dimethylsilyl(tert-butylamino)(tetramethylcyclopentadienyl)dimethyltitanium, dimethylsilyl(tert-butylamino)(4-pyrrolo-indenyl)dimethyltitanium, (η 5 At least one of (indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride, dimethylsilyl(tert-butylamino)(3,6-di-tert-butyl-fluorenyl)dimethyltitanium, and [(7-methyl-tetrahydroquinoline-8-yl)tetramethylcyclopentadienyl-N]dimethyltitanium; more preferably, it includes diphenylmethylene(cyclopentadienyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene(cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride, and (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride.

[0022] In one optional embodiment, the cocatalyst comprises at least one of tris(pentafluorophenyl)boron, triphenylcarbium tetra(pentafluorophenyl)boron, and N,N-dimethylaniline tetra(pentafluorophenyl)boron. Optionally, the cocatalyst is N,N-dimethylaniline tetra(pentafluorophenyl)boron.

[0023] In one optional embodiment, the mass ratio of the ethylene monomer to the α-olefin monomer is (40-85):100.

[0024] In one optional embodiment, the mass ratio of the ethylene monomer to hydrogen is 1:(0-9×10⁻⁶). -4 ).

[0025] In one optional embodiment, the amount of alkane solvent used is 55%-75% based on the mass of the raw material.

[0026] In one alternative embodiment, the amount of impurity remover used is 8-20 ppm based on the mass of the raw material.

[0027] In one optional embodiment, the amount of the main catalyst is 0.05-0.15 ppm based on the mass of the raw material.

[0028] In one alternative embodiment, the amount of co-catalyst used is 0.1-0.4 ppm based on the mass of the raw material.

[0029] In this invention, the polymerization reaction pressure is 3-5 MPaG, where MPaG is gauge pressure, and the reaction time in the reactor is 5-10 min.

[0030] The technical solution of this invention has the following advantages:

[0031] This invention provides a method for the continuous polymerization of ethylene and α-olefins, wherein the feed temperature of the raw materials is 10-30°C; the polymerization reaction temperature is 120-150°C; the raw materials include ethylene monomer, α-olefin monomer, alkane solvent, and a purification agent; or, the raw materials include ethylene monomer, α-olefin monomer, alkane solvent, a purification agent, and hydrogen; the ratio of the heat of heat removal from the raw materials to the heat of heat exchange in the polymerization reaction is Q, where 50% < Q < 85%. Where Xc is the mass percentage of structural units from α-olefin monomers in the polymer, Tr is the polymerization temperature in °C, Ta is the feed temperature in °C, and W is the reaction solids content; W = polymer yield / total feed amount × 100%; wherein, the total feed amount includes the feed amounts of raw materials, main catalyst, and co-catalyst; the formula in the method of this invention includes four variables, Xc, Tr, Ta, and W, forming a multi-parameter linkage control system, controlling the Q value within 50% < Q < 85%, realizing the control of the polymerization reaction, reducing the difference between the feed temperature and the polymerization temperature, improving the uniformity of temperature distribution, and effectively improving the polymerization activity; the feed temperature of the raw materials in this invention is 10-30 °C, which greatly reduces energy costs compared to the prior art of cooling the raw materials to below 0 °C or even lower temperatures; and the obtained polymer has good fluidity, will not clog the equipment, is conducive to the long-term operation of the equipment, and reduces operating costs. Detailed Implementation

[0032] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having” and any variations thereof in the text of this invention are intended to cover non-exclusive inclusion.

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] The "range" disclosed in this invention is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This range can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. In this invention, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers from a to b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed herein; "0-5" is merely a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥ 2, it is equivalent to disclosing that the parameter can be, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0036] In the description of the embodiments of the present invention, the term "and / or" is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0037] In the description of the embodiments of the present invention, the term "at least one" refers to one or more (including two).

[0038] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0039] Table 1. Raw material sources and specifications

[0040]

[0041] Example 1

[0042] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0043] IsoparE (1000 kg / h), 1-butene (310 kg / h), ethylene monomer (143 kg / h), and triisobutylaluminum (20 g / h) were mixed under a pressure of 4.2 MPaG, and the temperature was adjusted to 10°C. The mixture was then fed into a 250 L stirred reactor preheated to 120°C. (η) 5(Indene)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 101 mg / h and 400 mg / h, respectively. The polymerization reaction was carried out at 120 °C. After the reaction was carried out in the reactor for 7 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0044] Example 2

[0045] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0046] IsoparE (682 kg / h), 1-butene (279 kg / h), ethylene monomer (112 kg / h), and triisobutylaluminum (11 g / h) were mixed at a pressure of 4.2 MPaG, and the temperature was adjusted to 20°C before being fed into a 250 L stirred reactor preheated to 120°C; (η 5 (Indene)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 61 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 120 °C. After the reaction was carried out in the reactor for 10 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0047] Example 3

[0048] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0049] Industrial hexane (845 kg / h), 1-butene (286 kg / h), ethylene monomer (164 kg / h), hydrogen (2 g / h), and triisobutylaluminum (16 g / h) were mixed at a pressure of 4.2 MPaG, and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 120°C. (η) 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 71 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 120 °C. After the reaction was carried out in the reactor for 8 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0050] Example 4

[0051] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0052] IsoparE (702 kg / h), 1-butene (274 kg / h), ethylene monomer (161 kg / h), hydrogen (2 g / h), and triisobutylaluminum (16 g / h) were mixed at a pressure of 4.2 MPaG, and the temperature was adjusted to 10°C before being fed into a 250 L stirred reactor preheated to 140°C; (η 5 (Indene)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 71 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 140 °C. After the reaction was carried out in the reactor for 9 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0053] Example 5

[0054] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0055] IsoparE (706 kg / h), 1-butene (270 kg / h), ethylene monomer (198 kg / h), hydrogen (160 g / h), and triisobutylaluminum (16 g / h) were mixed at a pressure of 4.2 MPaG, and the temperature was adjusted to 20°C. The mixture was then fed into a 250 L stirred reactor preheated to 140°C. (η) 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 89 mg / h and 290 mg / h, respectively. The polymerization reaction was carried out at 140 °C. After the reaction was carried out in the reactor for 9 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0056] Example 6

[0057] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0058] IsoparE (779 kg / h), 1-butene (226 kg / h), ethylene monomer (169 kg / h), hydrogen (40 g / h), and triisobutylaluminum (21 g / h) were mixed at a pressure of 4.2 MPaG, and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 140°C. (η) 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 102 mg / h and 380 mg / h, respectively. The polymerization reaction was carried out at 140 °C. After the reaction was carried out in the reactor for 9 min, the polymer solution was discharged from the reactor outlet and heated to 260 °C to remove volatile components. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0059] Example 7

[0060] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0061] Under a pressure of 4.2 MPaG, IsoparE (685 kg / h), 1-butene (298 kg / h), ethylene monomer (178 kg / h), hydrogen (2 g / h), and triisobutylaluminum (15 g / h) were mixed and the temperature was adjusted to 10°C. The mixture was then fed into a 250 L stirred reactor preheated to 150°C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 112 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150°C. After the reaction was carried out in the reactor for 9 minutes, the polymer solution was discharged from the reactor outlet. After being heated to 260°C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0062] Example 8

[0063] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0064] Under a pressure of 4.2 MPaG, IsoparE (685 kg / h), 1-butene (212 kg / h), ethylene monomer (165 kg / h), hydrogen (2 g / h), and triisobutylaluminum (13 g / h) were mixed and the temperature was adjusted to 20°C. The mixture was then fed into a 250 L stirred reactor preheated to 150°C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 101 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150°C. After the reaction was carried out in the reactor for 10 min, the polymer solution was discharged from the reactor outlet. After being heated to 260°C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0065] Example 9

[0066] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0067] Under a pressure of 4.2 MPaG, IsoparE (700 kg / h), 1-butene (213 kg / h), ethylene monomer (180 kg / h), hydrogen (70 g / h), and triisobutylaluminum (13 g / h) were mixed and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 150°C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 109 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150°C. After the reaction was carried out in the reactor for 10 min, the polymer solution was discharged from the reactor outlet. After being heated to 260°C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0068] Example 10

[0069] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0070] IsoparE (698 kg / h), 1-octene (224 kg / h), ethylene monomer (95 kg / h), and triisobutylaluminum (10 g / h) were mixed under a pressure of 4.2 MPaG, and the temperature was adjusted to 10 °C. The mixture was then fed into a 250 L stirred reactor preheated to 135 °C. Diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 62 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135 °C. After the reaction was carried out in the reactor for 10 min, the polymer solution was discharged from the reactor outlet. After being heated to 260 °C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0071] Example 11

[0072] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0073] IsoparE (756 kg / h), 1-octene (276 kg / h), ethylene monomer (112 kg / h), and triisobutylaluminum (10 g / h) were mixed under a pressure of 4.2 MPaG, and the temperature was adjusted to 20°C. The mixture was then fed into a 250 L stirred reactor preheated to 135°C. Diphenylmethylene (cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 60 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135°C. After the reaction was carried out in the reactor for 9 min, the polymer solution was discharged from the reactor outlet. After being heated to 260°C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0074] Example 12

[0075] This embodiment provides a method for the continuous polymerization of ethylene and α-olefins, including the following steps:

[0076] IsoparE (736 kg / h), 1-octene (267 kg / h), ethylene monomer (136 kg / h), and triisobutylaluminum (10 g / h) were mixed under a pressure of 4.2 MPaG, and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 135°C. Diphenylmethylene (cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 65 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135°C. After the reaction was carried out in the reactor for 9 min, the polymer solution was discharged from the reactor outlet. After being heated to 260°C by a heater, volatile components were removed. The separated product was granulated by an extrusion pelletizing system to obtain granular polymer.

[0077] Comparative Example 1

[0078] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the procedure of Example 4, except that the feed rate of IsoparE is 1023 kg / h, the feed rate of triisobutylaluminum is 39 g / h, and the temperature is adjusted to 5°C. (η) 5 The feed rate for (indene)dimethylsilyl(tert-butyl)amide)titanium dichloride is 460 mg / h, and the feed rate for N,N-dimethylaniline tetra(pentafluorophenyl)boron is 1200 mg / h.

[0079] Comparative Example 2

[0080] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the procedure of Example 6, except that the feed rate of IsoparE is 655 kg / h, the feed rate of triisobutylaluminum is 43 g / h, and the temperature is adjusted to 35°C. (η) 5 The feed rate for (indene)dimethylsilyl(tert-butyl)amide-1,4-dichlorotitanium chloride is 230 mg / h, and the feed rate for N,N-dimethylaniline tetra(pentafluorophenyl)boron is 700 mg / h.

[0081] Comparative Example 3

[0082] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 8, except that the feed rate of triisobutylaluminum is 21 g / h, the feed rate of diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride is 340 mg / h, the feed rate of N,N-dimethylaniline tetra(pentafluorophenyl)boron is 450 mg / h, the preheating temperature of the reactor is 115°C, and the polymerization temperature is 115°C.

[0083] Comparative Example 4

[0084] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 10, except that the temperature is adjusted to 5°C, the feed rate of diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride is 230 mg / h, and the feed rate of N,N-dimethylaniline tetra(pentafluorophenyl)boron is 400 mg / h.

[0085] Comparative Example 5

[0086] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 11, except that the IsoparE feed rate is 356 kg / h, the temperature is adjusted to 35°C, and the feed rate of diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride is 130 mg / h.

[0087] Comparative Example 6

[0088] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 11, except that the feed rate of IsoparE is 908 kg / h, the feed rate of diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butylfluorenyl)zirconium dichloride is 150 mg / h, the preheating temperature of the reactor is 155°C, and the polymerization temperature is 155°C.

[0089] Comparative Example 7

[0090] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 1, except that the temperature is adjusted to -10°C.

[0091] Comparative Example 8

[0092] This comparative example provides a method for the continuous polymerization of ethylene and α-olefins, following the method of Example 1, except that the temperature is adjusted to 50°C.

[0093] Test case

[0094] The method for determining the mass percentage (Xc) of structural units derived from α-olefin monomers in polymers was as follows: High-temperature gel permeation chromatography-infrared spectroscopy (GPC-IR) was used with 1,2,4-trichlorobenzene as the mobile phase and polystyrene as the standard. The polymer sample was measured at 150℃. The standard concentration was 0.1 mg / mL, the solvent flow rate was 1.0 mL / min, and the standard parameters were K=59.1, α=0.69. The parameters for the sample were K=14.1, α=0.70.

[0095] The continuous polymerization reaction of ethylene and α-olefins was carried out after the reaction solids were stabilized. The reactor temperature and feed temperature were measured twice consecutively. The temperature fluctuation was considered to be less than 1°C after the reaction was stabilized. For more accurate measurement, the time from the first hour to the second hour after the stable operation was taken as the time. The polymer yield and total feed amount were calculated and substituted into the formula = polymer yield / total feed amount × 100% (the time period from the first hour to the second hour after the stable operation).

[0096] ;

[0097] Table 2. Parameters and Results for Q-Value Calculation

[0098]

[0099] Polymer yield is the mass of polymer produced per unit time.

[0100] The weight-average molecular weight and molecular weight distribution (PDI) of the polymer were determined using high-temperature gel permeation chromatography-infrared spectroscopy (GPC-IR) with 1,2,4-trichlorobenzene as the mobile phase and polystyrene as the standard. The polymer samples were measured at 150 °C with a standard concentration of 0.1 mg / mL and a solvent flow rate of 1.0 mL / min. The standard parameters were K=59.1 and α=0.69, while the parameters for the test samples were K=14.1 and α=0.70.

[0101] The formula for calculating polymerization activity is: mass of polymer obtained in 1 hour / amount of main catalyst used.

[0102] The electrical energy consumed by the refrigeration unit (for cooling raw materials and reaction equipment) and the electric heating system (for heating raw materials and reaction liquid) when producing 1 ton of polymer is calculated.

[0103] Test method for reactor blockage degree: The polymer is cast into a 0.2 mm thick film at 120℃. Six films with an area of ​​10 cm × 10 cm are randomly cut. The number of gel points on each film is counted manually. This is repeated 3 times, and the average value is magnified 100 times. The density of gel points per m³ is calculated. 2 The number of gel points in the membrane indicates a high degree of polymer blockage on the reactor walls.

[0104] Specific test parameters are shown in Table 3;

[0105] Table 3. Relevant Test Parameters for Polymers and Polymerization Systems

[0106]

[0107] As can be seen from the data in Table 3, compared with Example 1, Comparative Example 7 requires more energy to lower the temperature to -10°C, and Comparative Example 8 requires more energy to raise the temperature to 50°C. Furthermore, in Comparative Example 7, the polymerization activity is greatly reduced, and the polymer obtained has the highest gel point.

[0108] This invention reduces the temperature difference between the raw material feed temperature and the polymerization temperature, improves the uniformity of temperature distribution, and effectively enhances polymerization activity. The raw material feed temperature is 10-30℃, which greatly reduces energy costs compared to existing technologies that cool the raw material to below 0℃ or even lower temperatures. Furthermore, the resulting polymer has good flowability, does not clog equipment, and is conducive to long-term equipment operation, thus reducing operating costs.

[0109] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 1000 kg / h of IsoparE, 310 kg / h of 1-butene, 143 kg / h of ethylene monomer, and 20 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 10°C, and the mixture was fed into a 250 L stirred reactor preheated to 120°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 101 mg / h and 400 mg / h, respectively. The polymerization reaction was carried out at 120 °C. The reaction was stopped after 7 min in the reactor to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 73.7%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 34.3%; Tr is the polymerization temperature in °C, which is 120; Ta is the feed temperature in °C, which is 10; and W is the reaction solids content, which is 14.2 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes IsoparE, 1-butene, ethylene monomer, triisobutylaluminum, (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

2. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 682 kg / h of IsoparE, 279 kg / h of 1-butene, 112 kg / h of ethylene monomer, and 11 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 20°C, and the mixture was fed into a 250 L stirred reactor preheated to 120°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 61 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 120 °C. The reaction was stopped after 10 min in the reactor to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 67.0%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 36.5%; Tr is the polymerization temperature in °C, which is 120; Ta is the feed temperature in °C, which is 20; and W is the reaction solids content, which is 14.4 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes IsoparE, 1-butene, ethylene monomer, triisobutylaluminum, (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

3. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 845 kg / h of industrial hexane, 286 kg / h of 1-butene, 164 kg / h of ethylene monomer, 2 g / h of hydrogen, and 16 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 30°C, and the mixture was fed into a 250 L stirred reactor preheated to 120°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 71 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 120 °C. The reaction was stopped after 8 min in the reactor to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 51.4%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 34.8%; Tr is the polymerization temperature in °C, which is 120; Ta is the feed temperature in °C, which is 30; and W is the reaction solids content, which is 16.7 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes industrial hexane, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, and (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

4. A method for continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 702 kg / h of IsoparE, 274 kg / h of 1-butene, 161 kg / h of ethylene monomer, 2 g / h of hydrogen, and 16 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 10°C, and the mixture was fed into a 250 L stirred reactor preheated to 140°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 71 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 140 °C. The reaction was stopped after 9 min in the reactor to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 66.1%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 31.9%; Tr is the polymerization temperature in °C, which is 140; Ta is the feed temperature in °C, which is 10; and W is the reaction solids content, which is 18.4 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

5. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 706 kg / h of IsoparE, 270 kg / h of 1-butene, 198 kg / h of ethylene monomer, 160 g / h of hydrogen, and 16 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 20°C, and the mixture was fed into a 250 L stirred reactor preheated to 140°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 89 mg / h and 290 mg / h, respectively. The polymerization reaction was carried out at 140 °C and the reaction was terminated after 9 min in the reactor to obtain the polymer. The ratio of the heat of heat removal from the raw materials to the heat exchange during polymerization is Q, and Q is 55.0%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 23.5%; Tr is the polymerization temperature in °C, which is 140; Ta is the feed temperature in °C, which is 20; and W is the reaction solids content, which is 19.3 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

6. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 779 kg / h of IsoparE, 226 kg / h of 1-butene, 169 kg / h of ethylene monomer, 40 g / h of hydrogen, and 21 g / h of triisobutylaluminum were mixed, the temperature was adjusted to 30°C, and the mixture was fed into a 250 L stirred reactor preheated to 140°C; (η 5 -(indenyl)dimethylsilyl(tert-butyl)amido)titanium dichloride and N,N-dimethylanilinetetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 102 mg / h and 380 mg / h, respectively. The polymerization reaction was carried out at 140 °C. The reaction was stopped after 9 min in the reactor to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 53.2%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 26.2%; Tr is the polymerization temperature in °C, which is 140; Ta is the feed temperature in °C, which is 30; and W is the reaction solids content, which is 18.6 wt%. W = Polymer yield / Total feed rate × 100%; The total feed includes IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, (η 5 The feed rates of (indenyl)dimethylsilyl(tert-butyl)amide-1,4-dimethylaniline tetra(pentafluorophenyl)boron.

7. A method for continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 685 kg / h of IsoparE, 298 kg / h of 1-butene, 178 kg / h of ethylene monomer, 2 g / h of hydrogen, and 15 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 10 °C. The mixture was then fed into a 250 L stirred reactor preheated to 150 °C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 112 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150 °C. After a 9-minute reaction in the reactor, the reaction was terminated, yielding the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 70.1%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 25.5%; Tr is the polymerization temperature in °C, which is 150; Ta is the feed temperature in °C, which is 10; and W is the reaction solids content, which is 17.9 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

8. A method for continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 685 kg / h of IsoparE, 212 kg / h of 1-butene, 165 kg / h of ethylene monomer, 2 g / h of hydrogen, and 13 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 20°C. The mixture was then fed into a 250 L stirred reactor preheated to 150°C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added to the reactor separately at feed rates of 101 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150°C. After the reaction was carried out in the reactor for 10 min, the reaction was terminated to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 66.4%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 21.6%; Tr is the polymerization temperature in °C, which is 150; Ta is the feed temperature in °C, which is 20; and W is the reaction solids content, which is 17.1 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

9. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 700 kg / h of IsoparE, 213 kg / h of 1-butene, 180 kg / h of ethylene monomer, 70 g / h of hydrogen, and 13 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 150°C. Diphenylmethylene (cyclopentadienyl)(9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 109 mg / h and 250 mg / h, respectively. The polymerization reaction was carried out at 150°C. After the reaction was carried out in the reactor for 10 min, the reaction was terminated to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 58.2%. ； Wherein, Xc is the mass percentage of structural units from 1-butene in the polymer, which is 20.7%; Tr is the polymerization temperature in °C, which is 150; Ta is the feed temperature in °C, which is 30; and W is the reaction solids content, which is 17.9 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-butene, ethylene monomer, hydrogen, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (9-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

10. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 698 kg / h of IsoparE, 224 kg / h of 1-octene, 95 kg / h of ethylene monomer, and 10 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 10 °C. The mixture was then fed into a 250 L stirred reactor preheated to 135 °C. Diphenylmethylene (cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 62 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135 °C. After the reaction was carried out in the reactor for 10 min, the reaction was terminated to obtain the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 84.4%. ； Wherein, Xc is the mass percentage of structural units from 1-octene in the polymer, which is 37.5%; Tr is the polymerization temperature in °C, which is 135; Ta is the feed temperature in °C, which is 10; and W is the reaction solids content, which is 14.4 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-octene, ethylene monomer, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

11. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 756 kg / h of IsoparE, 276 kg / h of 1-octene, 112 kg / h of ethylene monomer, and 10 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 20°C. The mixture was then fed into a 250 L stirred reactor preheated to 135°C. Diphenylmethylene (cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 60 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135°C. After a 9-minute reaction in the reactor, the reaction was terminated, yielding the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 76.3%. ； Wherein, Xc is the mass percentage of structural units from 1-octene in the polymer, which is 36.1%; Tr is the polymerization temperature in °C, which is 135; Ta is the feed temperature in °C, which is 20; and W is the reaction solids content, which is 14.5 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-octene, ethylene monomer, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

12. A method for the continuous polymerization of ethylene and α-olefins, characterized in that, Includes the following steps: Under a pressure of 4.2 MPa, 736 kg / h of IsoparE, 267 kg / h of 1-octene, 136 kg / h of ethylene monomer, and 10 g / h of triisobutylaluminum were mixed and the temperature was adjusted to 30°C. The mixture was then fed into a 250 L stirred reactor preheated to 135°C. Diphenylmethylene (cyclopentadienyl)(2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron were added separately to the reactor at feed rates of 65 mg / h and 200 mg / h, respectively. The polymerization reaction was carried out at 135°C. After a 9-minute reaction in the reactor, the reaction was terminated, yielding the polymer. The ratio of the heat of material removal to the heat exchange in the polymerization reaction is Q, and Q is 59.0%. ； Wherein, Xc is the mass percentage of structural units from 1-octene in the polymer, which is 34.2%; Tr is the polymerization temperature in °C, which is 135; Ta is the feed temperature in °C, which is 30; and W is the reaction solids content, which is 16.9 wt%. W = Polymer yield / Total feed rate × 100%; The total feed amount includes the feed amounts of IsoparE, 1-octene, ethylene monomer, triisobutylaluminum, diphenylmethylene (cyclopentadienyl) (2,7-di-tert-butyl-fluorenyl)zirconium dichloride and N,N-dimethylaniline tetra(pentafluorophenyl)boron.

13. The method according to any one of claims 1-12, characterized in that, After the polymerization reaction, the process also includes steps for removing volatile components and granulation.

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