| 摘要 |
PURPOSE:To prepare a biaxially oriented polypropylene hollow article having excellent rigidity and transparency, and free from surface roughening, by biaxially orienting a hollow molded article made of a crystalline polymer of propylene or copolymer of propylene and other alpha-olefin, and inorganic fine powders. CONSTITUTION:100 parts by weight of a crystalline propylene polymer or copolymer of propylene and <= 10% of other alpha-olefin, having an MI of 0.1-3, pref. 0.1-1, is mixed with 0.0005-0.1 part of inorganic fine powders such as magnesium silicate. The polymer composition is extruded to a tubular parison, and cooled. The cooled parison is re-heated, longitudinally oriented using tapered tube, etc., and laterally oriented by expanding in a mold, to obtain the objective polypropylene biaxially oriented hollow article. |
