阅读说明：本技术 用来产生聚合物的反应设置和程序 (Reaction set-up and procedure for producing polymers ) 是由 詹尼·马尔凯蒂 乔瓦尼·雷加蒂 于 2019-06-11 设计创作，主要内容包括：本发明涉及用来产生聚合物的溶液聚合程序,其包含以下步骤：将一种或多种单体、相对于试剂混合物70重量％与90重量％之间的量的一种或多种溶剂、以及催化剂系统连续进料至第一搅拌反应容积,在其中形成单个混合单元,在其中开始聚合,直到获得相对于所获得的最终转化率而言20％至70％的转化率,在与第一反应容积串联连接的至少一个第二搅拌反应容积中继续进行聚合,在其中形成两个或更多个混合单元,在第二搅拌反应容积的出口处获得单体的最终转化率。所述程序的特征在于,试剂混合物在第一反应容积中的平均停留时间在相对于整个反应容积的平均停留时间而言10％至25％的间隔内变化。(The present invention relates to a solution polymerization procedure for producing a polymer comprising the steps of: one or more monomers, one or more solvents in an amount between 70 and 90% by weight with respect to the reagent mixture, and a catalyst system are continuously fed to a first stirred reaction volume, in which a single mixing unit is formed, in which the polymerization is started until a conversion of 20 to 70% with respect to the final conversion obtained is obtained, the polymerization being continued in at least one second stirred reaction volume connected in series with the first reaction volume, in which two or more mixing units are formed, the final conversion of the monomers being obtained at the outlet of the second stirred reaction volume. The procedure is characterized in that the mean residence time of the reagent mixture in the first reaction volume varies in an interval of 10% to 25% with respect to the mean residence time of the entire reaction volume.)

1. A solution polymerization procedure for producing a polymer comprising the steps of:

continuously feeding one or more monomers, one or more solvents in an amount of between 70 and 90 wt. -%, preferably between 80 and 90 wt. -%, and a catalyst system to a first stirred reaction volume, wherein a single mixing unit is formed, wherein the polymerization is started until a conversion of 20 to 70% with respect to the final conversion obtained is obtained,

-continuing the polymerization in at least one second stirred reaction volume connected in series with said first reaction volume, in which two or more mixing units are formed, said final conversion of said monomers being obtained at the outlet of the second stirred reaction volume;

the procedure is characterized in that in the first reaction volume the mean residence time of the reagent mixture varies in an interval of 10% to 25% with respect to the mean residence time of the entire reaction volume.

2. The process according to claim 1, wherein in the first reaction volume the specific stirring power is greater than the specific stirring power of the volume connected to the first volume.

3. The process according to claim 2, wherein in the first reaction volume the stirring specific power is greater than 2kW/m³。

4. The process according to claim 3, wherein the specific stirring power is at 1kW/m in the reaction volume connected to the first volume³And 2kW/m³In the meantime.

5. The process of any one of claims 1 to 4, wherein the average residence time of the entire reaction volume is typically between 1 and 2 hours.

6. The polymerization procedure for producing a polymer according to any one of claims 1 to 5, wherein the average residence time of the monomer in the first reaction volume is from 15% to 20% of the total residence time of the entire reaction volume.

7. The polymerization procedure used to produce a polymer according to any one of claims 1 to 6, wherein the monomer is selected from butadiene, styrene, isoprene, acrylonitrile, olefins or dienes and mixtures thereof.

8. The polymerization procedure used to produce a polymer according to claim 7, wherein the monomer is 1, 3-butadiene.

9. The polymerization procedure used to produce a polymer according to any one of claims 1 to 8, wherein the solvent is selected from hexane, pentane, heptane, and mixtures thereof.

10. A reaction arrangement for producing a polymer comprising one or more stirred reactors connected in series; the arrangement is characterized in that:

the first stirred reactor is a single mixing unit, the reaction volume of which is equal to a value of 1/10 to 1/4 relative to the total reaction volume, wherein the total reaction volume is the sum of the reaction volumes of all reactors present;

the reactors connected in succession and in series with the first reactor each have a reaction volume in which two or more mixing units are present.

11. The reaction arrangement of claim 10, wherein the reaction volume of the first reactor is 1/8 to 1/5 of the total reaction volume, wherein the total reaction volume is the sum of the reaction volumes of all reactors present.

12. The reaction arrangement according to claims 10 and 11, wherein the number of reactors is from 2 to 5.

13. The reaction arrangement according to any one of claims 10 to 12, in which the first reactor is equipped with an agitator device having a single Rushton radial flow blade, or two or more Hydrofoil axial flow blades.

14. The reaction arrangement according to any one of claims 10 to 13, wherein the reactors successive to the first reactor are equipped with a stirrer device having two or more Rushton radial flow blades.

15. The polymerization procedure according to any one of claims 1 to 9 using the reaction setup according to any one of claims 10 to 14.

Detailed Description

The applicant also details the procedure of the subject of the present patent application with reference to figures 1 and 2.

The object of the procedure subject of the invention is to produce polymers, preferably starting from monomers selected from butadiene, styrene, isoprene, acrylonitrile, olefins such as propylene or ethylene, dienes and mixtures thereof. The reaction solvent used in the present invention is selected from the group consisting of hexane, pentane, heptane and mixtures thereof. Hexane and pentane are preferred. The procedure used to produce polybutadiene (HCBR) with a high content of 1.4 cis units is preferred.

One or more monomers, one or more solvents in an amount between 70 and 90 wt.%, preferably between 80 and 90 wt.%, and a catalyst system are fed to a first stirred reaction volume, wherein a single mixing unit is formed, wherein solution polymerization is initiated to produce a polymer. In said first reaction volume, the reagent mixture is maintained until a conversion of 20% to 70% with respect to the final conversion obtained is obtained.

The partially reacted reaction mixture continues to polymerize in the stirred reaction volume succeeding the first stirred reaction volume, wherein two or more mixing units are formed.

Continuing the polymerization in the at least one second stirred reaction volume wherein two or more mixing units are formed.

In the first reaction volume, the mean residence time of the reagent mixture varies in an interval of 10% to 25% with respect to the mean residence time of the entire reaction volume.

The average residence time for the entire reaction volume is generally between 1 and 2 hours.

Preferably, the mean residence time of the mixture in the first reaction volume varies in an interval of 15% to 20% with respect to the total residence time of the entire reaction volume, more preferably it is equal to 15%.

In the first reaction volume, the specific stirring power is preferably greater than the specific stirring power of the volumes which are successive to the first volume.

In the first reaction volume, the specific stirring power is preferably greater than 2kW/m³In successive reaction volumes, the specific stirring power is 1kW/m³And 2kW/m³In the meantime.

Another subject of the present patent application is a reaction arrangement for producing polymers comprising one or more stirred reactors connected in series; the arrangement is characterized in that:

the first stirred reactor is a single mixing unit, the reaction volume of which is equal to a value from 1/10 to 1/4 relative to the total reaction volume, wherein the total reaction volume is the sum of the reaction volumes of all reactors present;

the reactors connected in succession and in series with the first reactor each have a reaction volume in which two or more mixing units are present.

Preferably, the reaction volume of the first reactor is 1/8 to 1/5 of the total reaction volume, more preferably equal to 1/6 of the total reaction volume, wherein the total reaction volume is the sum of the reaction volumes of all reactors present.

The number of reactors is preferably from 2 to 5, more preferably from 2 to 3.

The reactors successive to the first reactor are preferably identical to one another, have the same reaction volume and are equipped with the same stirrer devices.

The reaction arrangement claimed is preferably used to carry out the procedure as subject of the present patent application.

As mentioned, the first reaction volume is a single homogeneous mixing unit, while successive reaction volumes each have a plurality of mixing units.

In order to produce a mixing unit in the reactor, and thus in a single reaction volume, a stirrer arrangement is provided. The provision of the agitator means may affect the formation of a single homogeneous mixing unit or a plurality of homogeneous mixing units different from each other.

As known to the person skilled in the art, the type of blades used in the first reactor for the purpose of creating a single mixing unit may be, for example, a single Rushton radial flow blade, or two or more Hydrofoil axial flow blades connected to the same shaft, or equivalent solutions. The specific power transferred to the fluid from the stirrer means in the first reactor must be greater than the specific power used in the successive reactors, preferably greater than 2kW/m³. The reactors connected in succession and in series with the first reactor are provided with agitator means which divide the reaction volume of each reactor into one or more mixing units. As known to those skilled in the art, in order to produce polypeptidesThe purpose of the individual mixing units, the type of blades used in the reactors successive to the first reactor may comprise, for example, two or more Rushton radial flow blades, or equivalent solutions. The specific power transferred to the fluid from the stirrer means present in the reactor successive to the first reactor is less than that used in the first reactor and is preferably at 1kW/m³And 2kW/m³In the meantime. In addition, the first reactor and the successive reactors may optionally be equipped with a second stirrer device, the function of which is to scrape the reactor walls (wall scraper). In addition, the first reactor and successive reactors may optionally be equipped with a temperature controlled heat exchange system, which may be selected from external jackets, external coiled tubes, welded external half-tubes, internal coils, external heat exchangers, or other devices known to those skilled in the art, as is conventionally used in the industry.

The reaction temperature in the first reactor may be equal to 60 ℃ and the final temperature at the outlet of the final reactor may be equal to 110 ℃.

The applicant details the procedure and the reaction section in figure 2, which is the subject of this patent application.

However, the following description is not limited to the ratio between the reaction volumes shown in fig. 2.

Monomer (1), solvent (2) and catalyst system (3) are fed to a first reaction volume (a) where polymerization is started. The polymerization is then continued in the second reaction volume (B), reaching at its outlet the final conversion value of the monomer. The mean residence time of the mixture of the first reaction volume varies in an interval of from 10% to 25%, preferably from 15% to 20%, with respect to the mean residence time of the entire reaction volume, it being more preferably equal to 15%.

This means that the reagent mass containing the monomer is held in the reaction volume of the first reactor (a) for a significantly shorter time than the residence time of the reagent mass in the reaction volume of the second reactor (B).

The reaction volume of the first reactor (a) is equal to 1/6 of the total reaction volume, where the total reaction volume is the sum of the reaction volumes of all reactors present.

In the first reaction volume, the monomer achieves a conversion of 20% to 70%. The conversion is continued in successive reaction volumes, obtaining a final value at the outlet higher than 90%.

The reaction procedure and system as claimed solve the problems associated with the formation of contaminants, which may especially form in the first reaction volume.

The applicant has observed that in this way the operating cycle is extended and the quality of the product is improved, and at best it is possible to avoid the installation of a spare reactor for the first reactor, which is a common practice of prior art plants.

Some examples of applications of the invention will now be described; they are merely illustrative, and do not limit the scope, which represents preferred embodiments according to the present invention.

Comparative example 1.

The apparatus arrangement consists of two 50 cubic meter stirred reactors (diameter 2.8m, oval bottom, height 7.3m from bottom TL tangent to top TL tangent) each connected in series. Feeding to the first reactor a stream consisting of: 37,000kg/h of solvent mixed with 80% by weight of cyclohexane and 20% by weight of n-hexane; 5,000kg/h of 1, 3-butadiene at 20 ℃ and a catalyst composite having the following characteristics:

(a) neodymium versatate (40% by weight n-hexane solution) in a molar ratio H₂O/Nd is 0.001/1, and the molar ratio of total tertiary carboxylic acid (versatic acid)/Nd is 0.4

(b) Diisobutylaluminum hydride (DIBAH)

(c) Diethyl aluminum chloride (DEAC)

(d) Molar ratio Nd/Al/Cl [1/4/4mmol Nd/kg butadiene [ [2.0] mmol/kg

Each reactor was equipped with a stirrer having 3 radial turbines of 1.6m diameter with 6 vertical blades, with a stirrer speed of 50 revolutions per minute, fitted with a motor of 80 kW. A second stirrer, which scraped the wall of the reactor at a speed of 10 revolutions per minute and was equipped with a 10kW motor, was also provided.

The polymerization to form HCBR from butadiene was carried out adiabatically, with a final conversion of butadiene of 98%. The plant thus constructed was stopped after 3 weeks of operation, due to the formation of a large amount of contaminants in the reactor and the associated blockage of the stirrer in the first reactor.

Example 1:

the plant arrangement provides 2 reactors: a first stirred reactor of 15 cubic meters (diameter: 2.8m, TL-TL height: 1.7m) was followed by a second stirred reactor of 85 cubic meters (diameter: 2.8m, TL-TL height: 13m) connected in series. The first reactor was equipped with a stirrer device consisting of 1 radial turbine of diameter 1.6m and with 6 vertical blades, rotating at 60 revolutions per minute, equipped with a 45kW motor. The second reactor was equipped with a stirrer having 5 radial turbines of 1.6m diameter and 6 vertical blades, rotating at 50 revolutions per minute, equipped with a motor of 140 kW. A second stirrer, which scraped the wall of the reactor at a speed of 10 revolutions per minute and was equipped with a 10kW motor, was also provided. The stream described in comparative example 1 was fed to the first reactor. The polymerization to form HCBR from butadiene was carried out adiabatically, with a final conversion of butadiene of 98%. The apparatus thus constituted was operated for 6 weeks without any clogging being observed in any of the stirrers.