Patent · US Expired

Blends of polypropylenes

US5986009A · kind A · utility

42Cited by
7References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 23, 1998
Grant dateNov 16, 1999
Priority date
Expiry dateNov 23, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L2308/00
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The invention includes a blend composition comprising (a) about 1 to about 15 weight percent of amorphous polypropylene (b) about 99 to about 85 weight percent of crystalline polypropylene, wherein the molecular weight of the amorphous polypropylene is lower than the molecular weight of the crystalline polypropylene; the molecular weight (Mw) of the amorphous polypropylene is higher than about 50,000, preferably 100,000 g/mole; the amorphous polypropylene has a MWD less than about 3; and wherein the percentages are based on total amorphous plus crystalline polypropylene. Preferably, amorphous and crystalline polypropylenes are at least about 90 weight percent propylene units. Preferably, the amorphous polypropylene has a glass transition temperature greater than about -10.degree. C. The invention includes processes for preparing compositions of the invention, including a multistage process. Additionally the invention includes articles, sheets, films, foams and fibers comprising or prepared from compositions of the invention as well as processes for making the things, preferably processes involving stretching a composition of the invention. The processes include a process comprising…

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