Patent · US Expired

Preliminarily foamed particles of non-crosslinked polypropylene-type resin

US4567208A · kind A · utility

18Cited by
10References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 5, 1984
Grant dateJan 28, 1986
Priority date
Expiry dateDec 5, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/16
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Preliminarily foamed particles of a non-crosslinked polypropylene-type resin based on a mixture of 10 to 95% by weight of an alpha-olefin/propylene random copolymer having an amount of the heat of crystallization of not more than 10 cal/g in differential scanning calorimetry and 90 to 5% by weight of an ethylene/propylene random copolymer as a base resin, said preliminarily foamed particles having such a crystal structure that when a DSC curve is drawn by heating 1 to 3 mg of the preliminarily foamed particles to 220.degree. C. at a rate of 10.degree. C./min. by means of a differential scanning calorimeter, a high temperature peak is observed at a higher temperature than the temperature of the peak inherent to the base resin. These preliminarily foamed articles can be molded under lower vapor pressures than in the prior art.

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