Sumitomo Chemical Company, Limited

The Japan Steel Works, Ltd.

Masamichi Ishibashi

Tatsuo Hamanaka

Shigeki Inoue

Seiji Takamoto

Norimasa Oda

Takeshi Tominaga

Noboru Komine

Kenji Tomomitsu

Yuji Goto

Kanji Idehara

Twist kneading disks are arranged such that the width of a piece of disk is 0.1 to 0.5 times the cylinder inner diameter D, a helix angle &#x3b8; as an angle between a vertex of the front surface side of the disk and vertex of the rear surface side of the disk at the tip portion is in a range of 0&#xb0;&#x3c;&#x3b8;&#x3c;90&#xb0; in the reverse rotating direction of the screws as viewed from a cross section of the disk in the end direction of the screw shaft, and a phase angle E as an angle in correlation between the disks around the screw shaft is in a range of 0&#xb0;&#x3c;E&#x3c;90&#xb0;. The twist kneading disks are incorporated in the plasticization kneading portion at the length of more than 1.88 times the cylinder inner diameter D.

Kneading extruder

A process for producing a thermoplastic elastomer composition, which comprises the steps of:

Process for producing thermoplastic elastomer composition

A process for producing a thermoplastic elastomer composition which comprises dynamically cross-linking an olefine copolymer rubber and an olefine plastic using a twin-screw extruder, said process being characterized in that said twin-screw extruder comprises one or more kneading zones within a dynamically cross-linking area and the first kneading zone among said zones comprises a screw with forward kneading disks having a minimum thickness (T.sub.min) of less than 13 mm per disk. Said method enables production of a thermoplastic elastomer composition of good quality regardless of the scale of production.

Growing community of inventors

Hiroshima, Japan

Masamichi Ishibashi