Method of preparing elastic terpolymer

Patent metadata

Field	Value
Publication number	US-9611349-B2
Application number	US-201314888992-A
Country	US
Kind code	B2
Filing date	Oct 14, 2013
Priority date	Jun 10, 2013
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

The present invention relates to a method of preparing an ethylene/alpha-olefin/diene-based elastic copolymer having high viscosity and a high molecular weight, in which energy efficiency of the entire process is optimized. The method of preparing the elastic copolymer includes the steps of: copolymerizing an ethylene/alpha-olefin/diene-based elastic copolymer; and separating and removing the solvent and unreacted monomers from the polymer solution and recovering the elastic copolymer, by sequentially using a gas-liquid separator and a stripper in the purification of the solvent and unreacted monomers.

First claim

The invention claimed is:

1. A method of preparing an elastic terpolymer, comprising the steps of:
copolymerizing a monomer composition including 40 to 70% by weight of ethylene, 15 to 55% by weight of alpha olefin having 3 to 20 carbon atoms, and 0.5 to 20% by weight of diene in the presence of a metallocene catalyst and a solvent in a polymerization reactor so as to prepare a polymer solution including an ethylene-alpha olefin-diene-based copolymer; and
separating the solvent and unreacted monomers from the polymer solution by sequentially using an anhydrous gas-liquid separator and a steam stripper so as to recover the ethylene-alpha olefin-diene-based copolymer,
wherein 40 to 70% by weight of the total weight of all materials excluding the total polymer included in the polymer solution are separated and removed in the anhydrous gas-liquid separator, and a residual solvent and unreacted monomers are separated and removed in the steam stripper,
wherein the method comprises a process of removing the solvent and unreacted monomers from the polymer solution under conditions of a temperature of 150 to 160° C. and a pressure of 5 to 10 bar in an upper portion of the anhydrous gas-liquid separator, and
wherein the method comprises a process of removing the residual solvent and unreacted monomers, that are passed through the anhydrous gas-liquid separator, by applying steam as a carrier gas under conditions of a temperature of 140 to 180° C. and a pressure of 4 to 10 bar in the steam stripper.

2. The method of claim 1 , comprising the step of recovering the solvent and unreacted monomers included in the copolymer so that they are included in an amount of 10% by weight or less, based on the total weight of the copolymer, in the steam stripper.

3. The method of claim 1 , wherein a content of the ethylene-alpha olefin-diene-based copolymer included in the polymer solution before it is passed through the anhydrous gas-liquid separator is 10 to 20% by weight, and a content of the ethylene-alpha olefin-diene-based copolymer included in the polymer solution after it is passed through the anhydrous gas-liquid separator is 20 to 50% by weight.

4. The method of claim 1 , wherein the solvent and unreacted monomers separated from the anhydrous gas-liquid separator and the steam stripper are reused in copolymerization for the preparation of the ethylene-alpha olefin-diene-based copolymer.

5. The method of claim 1 , further comprising the step of preparing the copolymer in the form of bales or pellets, after the step of recovering the copolymer.

6. The method of claim 1 , wherein the metallocene catalyst is a catalytic composition including a first transition metal compound represented by the following Chemical Formula 1 and a second transition metal compound represented by the following Chemical Formula 2:

wherein R 1 to R 13 are the same as or different from each other, and each is independently hydrogen, an alkyl radical having 1 to 20 carbon atoms, an alkenyl radical having 2 to 20 carbon atoms, an aryl radical having 6 to 20 carbon atoms, a silyl radical, an alkylaryl radical having 7 to 20 carbon atoms, an arylalkyl radical having 7 to 20 carbon atoms, or a hydrocarbyl-substituted metalloid radical of a Group IV metal; of R 1 to R 13 , two different neighboring groups are connected to each other by an alkylidine radical including an alkyl having 1 to 20 carbon atoms or an aryl radical having 6 to 20 carbon atoms to form an aliphatic or aromatic ring;
M is a Group IV transition metal;
Q 1 and Q 2 are the same as or different from each other, and each is independently a halogen radical, an alkyl radical having 1 to 20 carbon atoms, an alkenyl radical having 2 to 20 carbon atoms, an aryl radical having 6 to 20 carbon atoms, an alkylaryl radical having 7 to 20 carbon atoms, an arylalkyl radical having 7 to 20 carbon atoms, an alkylamido radical having 1 to 20 carbon atoms, an arylamido radical having 6 to 20 carbon atoms, or an alkylidene radical having 1 to 20 carbon atoms.

7. The method of claim 1 , wherein the catalytic composition further includes one or more cocatalytic compounds selected from the group consisting of the following Chemical Formula 3, Chemical Formula 4, and Chemical Formula 5:
—[Al(R)—O] n —  [Chemical Formula 3]

wherein Rs are the same as or different from each other, and each is independently a halogen, a hydrocarbon having 1 to 20 carbon atoms, or a halogen-substituted hydrocarbon having 1 to 20 carbon atoms; and n is an integer of 2 or more;
D(R) 3   [Chemical Formula 4]

wherein R is the same as defined in Chemical Formula 3; and D is aluminum or boron;
[L-H] + [ZA 4 ] − or [L] + [ZA 4 ] −   [Chemical Formula 5]

wherein L is a neutral or cationic Lewis acid; H is a hydrogen atom; Z is an element of Group 13; and As are the same as or different from each other, and each is independently an aryl group having 6 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms, at which one or more hydrogen atoms are substituted or unsubstituted with a halogen, a hydrocarbon having 1 to 20 carbon atoms, an alkoxy, or a phenoxy.

8. The method of claim 1 , wherein alpha olefin is one or more selected from the group consisting of propylene, 1-butene, 1-hexene, and 1-octene, and the diene is one or more selected from the group consisting of 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-vinyl-2-norbornene, 1,4-hexadiene, and dicyclopentadiene.

Assignees

• Lg Chemical Ltd

Inventors

• Ko Jun-Seok
• Yoon Sung-Cheol
• Park Sung-Ho
• Choi Soo-Young

Classifications

• C08F6/12

  Separation of polymers from solutions · CPC title

• C08F6/10

  Removal of volatile materials, e.g. solvents {(C08F6/001, C08F6/003, C08F6/005, C08F6/006, C08F6/008, C08F6/02, C08F6/04 take precedence)} · CPC title

• C08F6/003

  from polymer solutions, suspensions, dispersions or emulsions without recovery of the polymer therefrom · CPC title

• C08F210/18 Primary

  with non-conjugated dienes, e.g. EPT rubbers · CPC title

• C08F4/6592

  containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring · CPC title