The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 23, 1985
Filed:
Feb. 10, 1984
Pierino Radici, Turate, IT;
Societa Italiana Resine S.T.R. S.p.A., both of, IT;
Enichimica Secondaria S.p.A, both of, IT;
Abstract
A method of copolymerization in suspension of ethylene with straight-chain alpha-olefins so as to obtain low-density copolymers in two copolymerization steps in an aliphatic hydrocarbon medium having a boiling point above 40.degree. C. In the first reaction step the medium is supplied with a high-activity Ziegler catalyst on a carrier and with ethylene and the alpha-olefin. The copolymerization reaction is carried out for between 20 seconds and 30 minutes and at a temperature between 45.degree. and 65.degree.. The resulting copolymer is used in the second reaction step as a nucleus for polymerizing ethylene and the alpha-olefin, the reaction medium being supplied with additional quantities of ethylene and alpha-olefins so as to maintain the concentration of alpha-olefin in the reaction medium at between 4 and 25% by weight per 100 parts by weight of reaction medium and so as to maintain the pressure of ethylene at between 5 and 25 bars, the reaction being performed at a temperature between 50.degree. and 80.degree. C. for between 1 and 3 hours.