Process for producing atactic polyolefin polymers
US4777216A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1987 |
| Grant date | Oct 11, 1988 |
| Priority date | — |
| Expiry date | Jan 30, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F297/08
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention relates to a process for the controlled polymerization of alpha-olefins selected from the group consisting of propylene and butylene in order to form a polymer containing by weight about 10% to 30% isotactic polyolefin, 25% to 70% atactic polyolefin and 0% to 65% by weight of an amorphous ethylene/olefin copolymer which process comprises combinations of the steps of: PA0 (a) homopolymerizing the alpha-olefin at a temperature of from about 0.degree. C. to about 90.degree. C. (preferably from about 20.degree. C. to about 60.degree. C.) in the presence of a high yield catalyst comprising a titanium compound supported on activated MgCl.sub.2 and metal alkyl compound wherein the metal is selected from the group consisting of the metals of groups II and III of the Periodic Table for a first period of time; PA0 (b) adding a comonomer such as ethylene to the system; and PA0 (c) copolymerizing the alpha-olefin and the comonomer with stirring in order to assure a more uniform composition of the reacting phase at a temperature of from about 0.degree. C. to about 90.degree. C. in the presence of the same catalyst as used in step (a), for a second period of time, wherein said firs…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.