PRODUCTION METHOD OF PROPYLENE-BASED BLOCK COPOLYMER

• Main Authors: SOGA KAZUKI, IWAI NOBUHIRO
• Format: Patent
• Language: English; Japanese
• Published: 03.08.2017
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PROBLEM TO BE SOLVED: To provide a production method of a propylene-based block copolymer capable of providing copolymer powder of good fluidity even if the copolymer is a sticky soft propylene-based block copolymer.SOLUTION: The production method of a propylene-based block copolymer is provided that includes a first polymerization step of polymerizing a propylene polymer component (A) in a first polymerization reactor, a transportation step of transporting the propylene polymer component (A) to a second polymerization reactor, and a second polymerization step of polymerizing a propylene copolymer component (B) in a second polymerization reactor. The propylene polymer component (A) in the transportation step has an average grain diameter of 1,000 μm or more. The second polymerization reactor in the second polymerization step is a specified horizontal polymerization reactor to which a fluidity modifier is fed and in which polymer powder has an average residence time of 1.2 hours or less after the fluidity modifier is fed. The fluidity modifier is an oil containing Si.SELECTED DRAWING: Figure 1 【課題】粘着性の軟質プロピレン系ブロック共重合体であっても、流動性が良好な共重合体の粉末が得られるプロピレン系ブロック共重合体の製造方法の提供。【解決手段】第１重合器でプロピレン重合体成分（Ａ）を重合する第１重合工程と、プロピレン重合体成分（Ａ）を第２重合器に移送する移送工程と、次いで、第２重合器でプロピレン共重合体成分（Ｂ）を重合する第２重合工程とを含むプロピレン系ブロック共重合体の製造方法であって、前記移送工程においてプロピレン重合体成分（Ａ）は平均粒径が１０００μｍ以上であり、前記第２重合工程において、前記第２重合器は特定の横型重合器であり、且つ、前記横型重合器に流動改質剤をフィードし、流動改質剤フィード後の重合体パウダーの平均滞留時間を１．２時間以下とするプロピレン系ブロック共重合体の製造方法。流動改質剤がＳｉを含むオイルであるプロピレン系ブロック共重合体の製造方法。【選択図】図１