Patent · US Expired

Expanded polypropylene resin beads and a molded article

US6313184A · kind A · utility

29Cited by
45References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 17, 2000
Grant dateNov 6, 2001
Priority date
Expiry dateMay 17, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2323/12
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Propylene resin beads for molding expansion molded articles having improved high temperature resistance include as base resin metallocene-catalyzed copolymers of propylene with at least one or more of ethylene and .varies.-olefins of 4 to 20 carbon atoms. The metallocene-catalyzed propylene copolymers are isotactic random copolymers characterized by a melting point higher than 140.degree. C. to 160.degree. C. and a melt flow rate (MFR) of not higher than 12 g/10 minutes, especially, 0.5 to 12 g/10 minutes. Expansion molded articles produced by expansion molding the expanded beads have a high temperature degree of deflection which is lower than that of metallocene-catalyzed propylene homopolymers and lower than that of Ziegler-Natta-catalyzed random propylene copolymers having the same comonomers and melting point.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.