Ethylene/butene-1 copolymers

• US 5,084,540 A
• Filed: 11/20/1990
• Issued: 01/28/1992
• Est. Priority Date: 08/02/1978
• Status: Expired due to Fees

• Current Assignee: Montedison S.p.A. (Government of France)
• Original Assignee: Montedison S.p.A. (Government of France)
• Inventors: Soverini, Arrigo, Albizzati, Enrico, Cuffiani, Illaro, Zucchini, Umberto
• Primary Examiner(s): Smith, Edward J.
• Application Number:
  US07/616,767
• Time in Patent Office: 434 Days
• Field of Search: 520/348.6
• US Class Current: 526/348.6
• CPC Class Codes: C08F 210/08 Butenes
• CPC Class Codes: C08F 210/16 Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• CPC Class Codes: C08F 2500/12 Melt flow index or melt flow ratio
• CPC Class Codes: C08F 2500/18 Bulk density
• CPC Class Codes: C08F 4/6555 and magnesium or compounds thereof

Abstract

Crystalline copolymers of ethylene and alpha-olefins CH₂ ═CHR in which R is an alkyl group having 2 to 8 carbon atoms, containing 0.5 to 3% by moles of polymerized alpha-olefin and having a density lower than 0.945 g/cc are obtained by polymerizing, in the gas phase, mixtures of ethylene and the alpha-olefins in contact with catalysts prepared from (1) Ti compounds supported on Mg halides and (2) organometallic compounds, which are active in the polymerization of ethylene but exhibit little, if any, activity in the homo- or copolymerization of the alpha-olefins.

Claims

1. Crystalline copolymers of ethylene with butene-1 having a density between 0.910 and 0.945 g/cc, and a butene-1 content of 0.5 to 3% by moles selected from the group consisting of:

a) a crystalline copolymer having a density of 0.945, a ratio R between the molar percentage of butene-1 and polymer density of 0.5, and a melting point of 130°

C.;

b) a crystalline copolymer having a density of 0.931, a ratio R between the molar percentage of butene-1 and polymer density of 0.8, and a melting point of 127°

C.;

c) a crystalline copolymer having a density of 0.9268, a ratio R between the molar percentage of butene-1 and polymer density of 1.5, and a melting point of 125°

C.;

d) a crystalline copolymer having a density of 0.921, a ratio R between the molar percentage of butene-1 and polymer density of 2.5, and a melting point of 121.5°

C.; and

e) a crystalline copolymer having a density of 0.910, a ratio R between the molar percentage of butene-1 and polymer density of 3.5, and a melting point of 110°

C.

2. A crystalline copolymer of ethylene with butene-1 having a density of 0.931, a ratio R between the molar percentage of butene-1 and polymer density of 0.8, and a melting point of 127°

C.

3. A crystalline copolymer of ethylene with butene-1 having a density of 0.9268, a ratio R between the molar percentage of butene-1 and polymer density of 1.5, and a melting point of 125°

C.

4. A crystalline copolymer of ethylene with butene-1 having a density of 0.921, a ratio R between the molar percentage of butene-1 and polymer density of 2.5, and a melting point of 121.5°

C.