Polyolefin type resinous composition

US6255390A · kind A · utility

Assignee

• Chisso Corporation · JP

Inventors

• Takehiko Enomoto · Chiba, JP
• Chikashi Okayama · Ichihara, JP

Key dates

• Filing date: Oct 12, 1999
• Grant date: Jul 3, 2001
• Expiry date: Oct 12, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L53/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A polyolefin type resinous composition comprising 99 to 80% by weight of a propylene type block copolymer [A] and 1 to 20% by weight of an ethylene type or styrene type elastomer [B] which being superior in a transparency, a coloring property and a dimensional stability is provided. The said polyolefin composition comprises the said [A] consisting of a propylene homopolymer component and an ethylene propylene copolymer component having respective limiting viscosities: [.eta.].sub.PP, [.eta.].sub.RC, weight %: W.sub.PP, W.sub.RC, and melt flow rates: [MFR].sub.PP, [MFR].sub.RC, as well as the said [B] having a limiting viscosity: [.eta.].sub.R and a melt flow rate: [MFR].sub.R, in such a way that the following relationships being established; EQU ([.eta.].sub.RC /[.eta.].sub.PP).times.(W.sub.PP /W.sub.RC)=0.2-3.0, EQU ([MFR].sub.RC /[MFR].sub.PP)=0.3-4.0, EQU [.eta.].sub.RC /[.eta.].sub.PP =0.7-1.2, EQU [.eta.].sub.RC >6.5, EQU [MFR].sub.R /[MFR].sub.PP =0.3-4, and EQU [.eta.].sub.R /[.eta.].sub.PP =0.7-1.2.