CN111808220A - A kind of preparation method of polyethylene functional new material - Google Patents

Abstract

The invention discloses a preparation method of a novel polyethylene functional material, which comprises the steps of firstly, enabling polymer-grade ethylene gas to enter a receiver, and then injecting a regulator into a mixer by using a delivery pump; pressurizing the gas material obtained in the step A by a secondary compressor, then feeding the gas material into a polymerization kettle, and continuously injecting a trace amount of initiator solution into the polymerization kettle by using a delivery pump to perform high-pressure polymerization on ethylene; and (3) introducing the polyethylene and unreacted ethylene from the polymerization kettle into a condenser for cooling, introducing the cooled polyethylene and unreacted ethylene into a high-pressure separator, then decompressing, and separating the unreacted ethylene and the unreacted oligomer by the high-pressure separator. According to the invention, unreacted ethylene and oligomer can be separated out through the high-pressure separator, ethylene entrained in the oligomer can be separated out through the oligomer knockout, and the ethylene receiver can receive ethylene separated out by the high-pressure separator and the oligomer knockout, so that unpolymerized ethylene can be conveniently recovered.

Description

A kind of preparation method of polyethylene functional new material

technical field

The invention relates to the technical field of material preparation, in particular to a preparation method of a new functional polyethylene material.

Background technique

Polyethylene is a thermoplastic resin obtained by polymerization of ethylene. Polyethylene is odorless, non-toxic, and feels like wax. It has excellent low temperature resistance, good chemical stability, and can withstand most acid and alkali erosion. It is insoluble in ordinary Solvent, low water absorption, excellent electrical insulation, polyethylene functional new material is a new material made of polyethylene as raw material.

In the preparation process of the new functional polyethylene material, ethylene needs to be polymerized, and in the existing preparation method, since the ethylene cannot be completely polymerized and cannot be effectively recovered, resources are wasted. Therefore, we have improved this and proposed a preparation method of a new functional polyethylene material.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned technical problems, the present invention provides the following technical solutions:

A preparation method of a new functional polyethylene material of the present invention comprises the following steps:

A. Put the polymer grade ethylene gas into the receiver, then pressurize it by the primary compressor, and use the transfer pump to inject the regulator into the mixer;

B, the gas material obtained in step A is pressurized by the secondary compressor, then enters the polymerization kettle, and simultaneously uses the transfer pump to continuously inject a trace initiator solution into the polymerization kettle to make ethylene carry out high-pressure polymerization;

C. The polyethylene and unreacted ethylene that will come out of the polymerization kettle are passed into the condenser for cooling, enter the high-pressure separator after cooling, and then depressurize, and separate the unreacted ethylene and oligomer by the high-pressure separator out, and then use the oligomer separator to separate the oligomers;

D, the mixer recycling in the step A that separates out ethylene in the step C is returned to use, and the oligomer isolated in the step C is discharged after the ethylene that is reclaimed entrained in the oligomer separator;

E, the polyethylene material coming out of the high-pressure separator in the step C is decompressed in the low-pressure separator, the residual ethylene in the polyethylene material is separated, and the separated ethylene enters the ethylene receiver and is received by the ethylene receiver. Return to the mixer in step A for recycling;

F, the polyethylene after the separation in the step E is added and sent to the pelletizer for underwater pelletizing, and then the pelletized material is dehydrated using a dewatering tank, and then sieved through a vibrating sieve, and the sieved pellets fall into the Magnetic separator to remove the entrained metal particles, and then enter the storage tank for storage;

G. Sampling and analyzing the materials in the storage tank of step F, the qualified products enter the blender for pneumatic circulation blending to obtain the finished polyethylene functional new material, and the unqualified products are sent to the external product storage tank for storage.

As a preferred technical solution of the present invention, the regulator in the step A is propylene, propane or ethane, the purity of the propylene is greater than 99%, the purity of the propane is greater than 97%, and the purity of the ethane greater than 95%.

As a preferred technical solution of the present invention, the pressure of the primary compressor in the step A is 29.43 MPa, and the pressure of the secondary compressor in the step B is 113-196.20 MPa.

As a preferred technical solution of the present invention, the initiator used in the step B is prepared by dissolving organic peroxide in liquid paraffin, and the concentration of the initiator is 1%-25%, and the consumption of the initiator is 0.003%-0.006% of polymer grade ethylene gas consumption.

As a preferred technical solution of the present invention, the air pressure strength after decompression in the high-pressure separator in the step C is 24.53-29.43 MPa.

As a preferred technical solution of the present invention, the purity of the polymerization-grade ethylene gas in the step A is not less than 99.9%, and the reaction temperature of the polymerization kettle in the step B is about 150°C.

As a preferred technical solution of the present invention, the pressure after decompression in the low-pressure separator in the step E is 49.1 kPa.

The beneficial effects of the invention are: the preparation method of the new functional polyethylene material can separate unreacted ethylene and oligomers through a high-pressure separator, and can separate the oligomers entrained in the oligomers through the oligomer separator. The ethylene is separated, and the ethylene receiver can receive the ethylene separated by the high pressure separator and the oligomer separator, so as to facilitate the recovery of unpolymerized ethylene, thereby reducing the waste of resources, and the ethylene received by the ethylene receiver It can be returned to the mixer for recycling, so that the waste of resources can be further reduced, so that the preparation method of the new functional polyethylene material can greatly reduce the waste of ethylene resources and reduce the production cost.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. In the attached image:

Fig. 1 is the flow chart of the preparation method of a kind of polyethylene functional new material of the present invention;

Fig. 2 is a material diagram of a preparation method of a new functional polyethylene material of the present invention.

Detailed ways

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.

Example 1:

As shown in Figure 1-2, a preparation method of a new functional polyethylene material of the present invention includes the following steps:

A. Put the polymer grade ethylene gas into the receiver, then pressurize it by the primary compressor, and use the transfer pump to inject the regulator into the mixer;

B, the gaseous material obtained in step A is pressurized by the secondary compressor, then enters the polymerization kettle, and simultaneously uses the transfer pump to continuously inject a trace initiator solution into the polymerization kettle to make ethylene carry out high-pressure polymerization;

C. The polyethylene and unreacted ethylene that will come out of the polymerization kettle are passed into the condenser for cooling, enter the high-pressure separator after cooling, and then depressurize, and separate the unreacted ethylene and oligomer by the high-pressure separator out, and then use the oligomer separator to separate the oligomers;

D, the mixer recycling in the step A that separates out ethylene in the step C is returned to use, and the oligomer isolated in the step C is discharged after the ethylene that is reclaimed entrained in the oligomer separator;

E, the polyethylene material coming out of the high-pressure separator in the step C is decompressed in the low-pressure separator, the residual ethylene in the polyethylene material is separated, and the separated ethylene enters the ethylene receiver and is received by the ethylene receiver. Return to the mixer in step A for recycling;

F, the polyethylene after the separation in the step E is added and sent to the pelletizer for underwater pelletizing, and then the pelletized material is dehydrated using a dewatering tank, and then sieved through a vibrating sieve, and the sieved pellets fall into the Magnetic separator to remove the entrained metal particles, and then enter the storage tank for storage;

G. Sampling and analyzing the materials in the storage tank of step F, the qualified products enter the blender for pneumatic circulation blending to obtain the finished polyethylene functional new material, and the unqualified products are sent to the external product storage tank for storage.

Wherein, the regulator in step A is propylene, the purity of propylene is 99.2%, and the regulator can adjust the relative mass of polyethylene molecules.

Wherein, the pressure of the primary compressor in step A is 29.43 MPa, and the pressure of the secondary compressor in step B is 113 MPa.

Wherein, the initiator used in the step B is made by dissolving organic peroxide in liquid paraffin, and the concentration of the initiator is 1%, the consumption of the initiator is 0.003 of the consumption of the polymer-grade ethylene gas, and the initiator can promote ethylene polymerization to improve the production efficiency of polyethylene.

Wherein, the air pressure strength after decompression in the high-pressure separator in step C is 24.53MPa.

Wherein, the purity of the polymerization-grade ethylene gas in step A is 99.92%, and the reaction temperature of the polymerization kettle in step B is 150 ° C. If the purity of the ethylene gas is low, the speed of polymerization will be slow, and there are many impurities, and the relative molecular weight of the product is low. .

Wherein, the pressure after decompression in the low-pressure separator in step E is 49.1 kPa.

Example 2:

As shown in Figure 1-2, a preparation method of a new functional polyethylene material of the present invention includes the following steps:

A. Put the polymer grade ethylene gas into the receiver, then pressurize it by the primary compressor, and use the transfer pump to inject the regulator into the mixer;

B, the gas material obtained in step A is pressurized by the secondary compressor, then enters the polymerization kettle, and simultaneously uses the transfer pump to continuously inject a trace initiator solution into the polymerization kettle to make ethylene carry out high-pressure polymerization;

C. The polyethylene and unreacted ethylene that will come out of the polymerization kettle are passed into the condenser for cooling, enter the high-pressure separator after cooling, and then depressurize, and separate the unreacted ethylene and oligomer by the high-pressure separator out, and then use the oligomer separator to separate the oligomers;

D, the mixer recycling in the step A that separates out ethylene in the step C is returned to use, and the oligomer isolated in the step C is discharged after the ethylene that is reclaimed entrained in the oligomer separator;

E, the polyethylene material coming out of the high-pressure separator in the step C is decompressed in the low-pressure separator, the residual ethylene in the polyethylene material is separated, and the separated ethylene enters the ethylene receiver and is received by the ethylene receiver. Return to the mixer in step A for recycling;

F, the polyethylene after the separation in the step E is added and sent to the pelletizer for underwater pelletizing, and then the pelletized material is dehydrated using a dewatering tank, and then sieved through a vibrating sieve, and the sieved pellets fall into the Magnetic separator to remove the entrained metal particles, and then enter the storage tank for storage;

G. Sampling and analyzing the materials in the storage tank of step F, the qualified products enter the blender for pneumatic circulation blending to obtain the finished polyethylene functional new material, and the unqualified products are sent to the external product storage tank for storage.

Wherein, the regulator in step A is propane, the purity of propane is 98%, and the regulator can adjust the relative mass of polyethylene molecules.

Wherein, the pressure of the primary compressor in step A is 29.43 MPa, and the pressure of the secondary compressor in step B is 130 MPa.

Wherein, the initiator used in step B is made by dissolving organic peroxide in liquid paraffin, and the concentration of the initiator is 10%, and the consumption of the initiator is 0.003% of the consumption of polymer-grade ethylene gas, and the initiator can promote The polymerization of ethylene improves the production efficiency of polyethylene.

Wherein, the air pressure strength after decompression in the high-pressure separator in step C is 26MPa.

Wherein, the purity of the polymerization-grade ethylene gas in step A is 99.94%, and the reaction temperature of the polymerization kettle in step B is 150° C. If the purity of the ethylene gas is low, the speed of polymerization will be slow, and there are many impurities, and the relative molecular weight of the product is low. .

Wherein, the pressure after decompression in the low-pressure separator in step E is 49.1 kPa.

Example 3:

As shown in Figure 1-2, a preparation method of a new functional polyethylene material of the present invention includes the following steps:

A. Put the polymer grade ethylene gas into the receiver, then pressurize it by the primary compressor, and use the transfer pump to inject the regulator into the mixer;

B, the gas material obtained in step A is pressurized by the secondary compressor, then enters the polymerization kettle, and simultaneously uses the transfer pump to continuously inject a trace initiator solution into the polymerization kettle to make ethylene carry out high-pressure polymerization;

C. The polyethylene and unreacted ethylene that will come out of the polymerization kettle are passed into the condenser for cooling, enter the high-pressure separator after cooling, and then depressurize, and separate the unreacted ethylene and oligomer by the high-pressure separator out, and then use the oligomer separator to separate the oligomers;

D, the mixer recycling in the step A that separates out ethylene in the step C is returned to use, and the oligomer isolated in the step C is discharged after the ethylene that is reclaimed entrained in the oligomer separator;

E, the polyethylene material coming out of the high-pressure separator in the step C is decompressed in the low-pressure separator, the residual ethylene in the polyethylene material is separated, and the separated ethylene enters the ethylene receiver and is received by the ethylene receiver. Return to the mixer in step A for recycling;

F, the polyethylene after the separation in the step E is added and sent to the pelletizer for underwater pelletizing, and then the pelletized material is dehydrated using a dewatering tank, and then sieved through a vibrating sieve, and the sieved pellets fall into the Magnetic separator to remove the entrained metal particles, and then enter the storage tank for storage;

G. Sampling and analyzing the materials in the storage tank of step F, the qualified products enter the blender for pneumatic circulation blending to obtain the finished polyethylene functional new material, and the unqualified products are sent to the external product storage tank for storage.

Wherein, the regulator in step A is ethane, the purity of ethane is 96%, and the regulator can adjust the relative mass of polyethylene molecules.

Wherein, the pressure of the primary compressor in step A is 29.43 MPa, and the pressure of the secondary compressor in step B is 196.20 MPa.

Wherein, the initiator used in step B is made by dissolving organic peroxide in liquid paraffin, and the concentration of the initiator is 25%, and the consumption of the initiator is 0.006% of the consumption of polymer-grade ethylene gas, and the initiator can promote The polymerization of ethylene improves the production efficiency of polyethylene.

Wherein, the air pressure strength after decompression in the high pressure separator in step C is 29.43MPa.

Wherein, the purity of the polymerization-grade ethylene gas in step A is 99.96%, and the reaction temperature of the polymerization kettle in step B is 150 ° C. If the purity of the ethylene gas is low, the speed of polymerization will be slow, and there are many impurities, and the relative molecular weight of the product is low. .

Wherein, the pressure after decompression in the low-pressure separator in step E is 49.1 kPa.

Finally, it should be noted that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it is still The technical solutions described in the foregoing embodiments may be modified, or some technical features thereof may be equivalently replaced. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (7)

1. The preparation method of the novel polyethylene functional material is characterized by comprising the following steps of:

A. the polymerization-grade ethylene gas enters a receiver, then is pressurized by a primary compressor, and a regulator is injected into a mixer by using a delivery pump;

B. pressurizing the gas material obtained in the step A by a secondary compressor, then feeding the gas material into a polymerization kettle, and continuously injecting a trace amount of initiator solution into the polymerization kettle by using a delivery pump to perform high-pressure polymerization on ethylene;

C. introducing polyethylene and unreacted ethylene from a polymerization kettle into a condenser for cooling, introducing into a high-pressure separator, reducing pressure, separating unreacted ethylene and oligomer by the high-pressure separator, and separating the oligomer by an oligomer separator;

D. returning the ethylene separated in the step C to the mixer in the step A for recycling, and discharging the oligomer separated in the step C after recovering the entrained ethylene in an oligomer knockout;

E. c, decompressing the polyethylene material from the high-pressure separator in the step C in a low-pressure separator, separating out residual ethylene in the polyethylene material, allowing the separated ethylene to enter an ethylene receiver, receiving the ethylene by an ethylene receiver, and returning the ethylene to the mixer in the step A for recycling;

F. e, feeding the polyethylene separated in the step E into a granulator for underwater granulation, dehydrating the cut granules by using a dehydration tank, sieving by using a vibrating screen, enabling the sieved granules to fall into a magnetic separator to remove entrained metal particles, and then entering a storage tank for storage;

G. and F, sampling and analyzing the materials in the storage tank in the step F, feeding the qualified products into a blender for pneumatic circulating blending to obtain the finished polyethylene new functional material, and feeding the unqualified products to an off-grade product storage tank for storage.

2. The method for preparing a new functional polyethylene material as claimed in claim 1, wherein the regulator in step a is propylene, propane or ethane, the purity of propylene is greater than 99%, the purity of propane is greater than 97%, and the purity of ethane is greater than 95%.

3. The method for preparing a new polyethylene functional material as claimed in claim 1, wherein the pressure of the primary compressor in step A is 29.43MPa, and the pressure of the secondary compressor in step B is 113-196.20 MPa.

4. The method as claimed in claim 1, wherein the initiator used in step B is prepared by dissolving organic peroxide in liquid paraffin, and the concentration of the initiator is 1% -25%, and the amount of the initiator is 0.003% -0.006% of the amount of the polymer grade ethylene gas.

5. The method for preparing a new functional polyethylene material as claimed in claim 1, wherein the strength of the gas pressure in the high pressure separator after pressure reduction in step C is 24.53-29.43 MPa.

6. The method for preparing a new functional polyethylene material as claimed in claim 1, wherein the purity of the polymerization grade ethylene gas in step A is not less than 99.9%, and the reaction temperature of the polymerizer in step B is about 150 ℃.

7. The method for preparing a new functional polyethylene material as claimed in claim 1, wherein the pressure of the depressurized material in the low pressure separator in the step E is 49.1 kPa.

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