Method of molding pipe of polybutene-1

Abstract

Abstract PURPOSE:To facilitate the transformation of crystals, by using two or more pipe diameter reducing plates having openings whose inner diameters are successively reduced more than the outer diameter of a pipe of polybutene-1 after cooled so that the outer diameter of the polybutene-1 may be reduced to 99.7-97.0% of the original diameter. CONSTITUTION:Butene-1 is polymerized using a Ziegler catalyst system to obtain crystalline polybutene-1. In case the polybutene-1 is melted and extruded into a pipe, the outer diameter of the polybutene-1 pipe after the cooling is reduced to 99.7-97.0% of the original diameter by using at least two pipe diameter reducing plates having openings whose inner diameters are successively reduced more than the outer diameter of the pipe of polybutene-1. The pipe diameter reducing plates 1 has openings having diameters to reduce the outer diameter of pipe at a desired ratio and may be made of any material which can reduce the outer diameter of the pipe with metals, ceramic, or the like being a preferred material.

Inventors

• 👤 Tsutomu Moriwaki
• 👤 森脇　勉
• 👤 Masaaki Hinaka
• 👤 日中　正昭
• 👤 Tsuneo Yoshishiba
• 👤 吉柴　常雄

Bibliographic Details