Process for producing thermoplastic olefinic elastomer
Abstract
Abstract A process for producing a thermoplastic elastomer in the presence of a Ziegler catalyst which comprises a first step of forming polypropylene and then a second step of forming an ethylene/propylene random copolymer, characterized in that (a) the catalyst is used such that the total amount of the polymer formed is at least 50 kg per gram of titanium metal in the catalyst, (b) a hydrocarbon having 3 or 4 carbon atoms is used as a slurry polymerization solvent, (c) the solvent phase of the slurry is evaporated and separated without bringing the resulting polymer into contact with alcohols and/or hydrocarbons having at least 5 carbon atoms, (d) the polymerization temperature in the second step is adjusted to not more than 50° C., and (e) in the first step, polypropylene is formed in an amount of 5 to 50% by weight based on the total weight of the elastomer, and in the second step, the ethylene/propylene random copolymer having a propylene content of 5 to 60% based on the weight of the ethylene/propylene random copolymer and an intrinsic viscosity at 135° C. in decalin of 1.5 to 15 is formed in an amount of 50 to 95% by weight based on the total weight of the elastomer.
Inventors
- 👤 Shigeru Saeda
- 👤 Zenichiro Izumi
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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