Method for producing heterophasic propylene polymerization material particles

Patent metadata

Field	Value
Publication number	US-2020308317-A1
Application number	US-202016829479-A
Country	US
Kind code	A1
Filing date	Mar 25, 2020
Priority date	Mar 29, 2019
Publication date	Oct 1, 2020
Grant date	—

Abstract

Provided is a particle drying method capable of sufficiently removing the volatile component and down-regulating the increase of the viscosity of the particles after the removal of the volatile component. There is provided a method for producing heterophasic propylene polymerization material particles, the method including: (1) performing monomer polymerization in the presence of a catalyst including a solid catalyst component so as to obtain a component I; (2) performing monomer polymerization in the presence of the component I so as to obtain the component II, so that particles including a volatile component are produced; and (3) causing the particles to contact with an inert gas-containing stream so as to remove the volatile component from the particles.

First claim

1 . A method for producing heterophasic propylene polymerization material particles, the method comprising:
(1) performing monomer polymerization in the presence of a catalyst including a solid catalyst component so as to obtain a component (I) recited below; (2) performing monomer polymerization in the presence of the component (I) so as to obtain a component (II), so that particles including a volatile component, the component (I), and the component (II) are produced; and (3) causing the particles to contact with an inert gas-containing stream so as to remove the volatile component from the particles, the particles including the component (I) by 20 to 70 mass %, and the component (II) by 30 to 80 mass %, and the method satisfying Inequation (1):
19.5≤ T 1.12 ·t 0.17 ·( C/ 100) 0.61 /( d ·(0.85· P ) 1/3 ) 0.13 ≤51.4  (1)

where T [° C.] is a temperature that the particles have when the particles contact with the inert gas-containing stream, t [h] is a contact time period in which the particles contact with the inert gas-containing stream, d [μm] is a median diameter that the solid catalyst component has at the time of start of step (1), P [g/g] is a mass of the particles per 1 g of the solid catalyst component, and C [mass %] is the content of the component (II) in the particles, the component (I) including a component (I-1) and/or a component (I-2), the component (I-1) being a propylene homopolymer, the component (I-2) being a propylene copolymer including a propylene-derived structural unit and at least one type of olefin-derived structural unit selected from the group consisting of ethylene and C4 to C12 α-olefins, wherein a mass ratio of the at least one type of olefin-derived structural unit in the mass of the copolymer is less than 15 mass %, and the component (II) being a propylene copolymer including a propylene-derived structural unit and at least one type of olefin-derived structural unit selected from the group consisting of ethylene and C4 to C12 α-olefins, wherein a mass ratio of the at least one type of olefin-derived structural unit in the mass of the copolymer is in a range of 15 to 80 mass %.

2 . The method according to claim 1 , wherein counter currents of the particles and the inert gas-containing stream are caused to contact with each other.

3 . The method according to claim 1 , wherein the following Inequation (2) is further satisfied:
26.5≤ T 1.12 ·t 0.17 ·( C/ 100) 0.61 /( d ·(0.85· P ) 1/3 ) 0.13   (2).

4 . The method according to claim 2 , wherein the following Inequation (2) is further satisfied:
26.5≤ T 1.12 ·t 0.17 ·( C/ 100) 0.61 /( d ·(0.85· P ) 1/3 ) 0.13   (2).

Assignees

• Sumitomo Chemical Co

Inventors

• Arakawa Masayuki

Classifications

• C08F6/00 Primary

  Post-polymerisation treatments (C08F8/00 takes precedence; of conjugated diene rubbers C08C) · CPC title

• C08F210/06

  Propene · CPC title

• C08F110/06

  Propene · CPC title

• C08L23/12

  Polypropene · CPC title

• C08L2308/00

  Chemical blending or stepwise polymerisation process with the same catalyst · CPC title