High temperature process for the production of atactic, amorphous, tacky propylene homopolymers or copolymers
OwnerJoseph M. Kelleyinventor
Life of this patent
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Abstract
Atactic, amorphous, and tacky poly-alpha-olefins containing 100%-65% propylene and optionally up to about 35% ethylene are prepared by polymerizing the monomer(s) at 180-450° F. and at a pressure sufficient to substantially maintain the monomer(s) in the liquid phase. The polymerization is carried out in the presence of catalyst system consisting of (a) a transition metal halide selected from the group consisting of (i) a titanium trihalide and an aluminum alkyl, (ii) a titanium halide on a comminuted magnesium halide support, and (iii) a titanium halide sandwich compound and (b) aluminum alkyl as a co-catalyst.
Claims17
A process for preparing an atactic, substantially amorphous, tacky propylene homopolymer, which comprises the steps of (a) introducing liquefied propylene into a reactor;
- (b) introducing a catalyst system into the reactor;
- (c) allowing the liquefied propylene to vaporize in the reactor;
- (d) polymerizing the vaporized propylene in the reactor;
- (e) discharging a mixture of the molten atactic, substantially amorphous, tacky homopolymer and the gaseous propylene from the reactor;
- and (f) separating the molten atactic, substantially amorphous, tacky homopolymer from the gaseous propylene;
- wherein the reactor is maintained at 300 to 450° F. and at a pressure of 600 to 5000 psig;
- and wherein the catalyst system consists essentially of (a) a transition metal halide catalyst selected from the group consisting of (i) a titanium trihalide, (ii) a titanium halide on a comminuted magnesium halide support, and (iii) a titanium halide sandwich compound and (b) an aluminum alkyl.
A process for preparing an atactic, substantially amorphous, tacky copolymer of propylene and ethylene, which comprises the steps of (a) introducing into a reactor liquefied propylene present in an amount of at least about 65% by weight and liquefied ethylene present in an amount of up to about 35% by weight, with the weight of the propylene and ethylene totaling 100%;
- (b) introducing a catalyst system into the reactor;
- (c) allowing the liquefied propylene and the liquefied ethylene to vaporize in the reactor;
- (d) polymerizing the vaporized propylene and vaporized ethylene in the reactor;
- (e) discharging a mixture of the molten atactic, substantially amorphous, tacky copolymer and gaseous propylene and gaseous ethylene from the reactor;
- and (f) separating the molten atactic, substantially amorphous, tacky copolymer from the gaseous propylene and the gaseous ethylene;
- wherein the reactor is maintained at 300 to 450° F. and at a pressure of 600 to 5000 psig;
- and wherein the catalyst system consists essentially of (a) a transition metal halide catalyst selected from the group consisting of (i) a titanium trihalide, (ii) a titanium halide on a comminuted magnesium halide support, and (iii) a titanium halide sandwich compound and (b) an aluminum alkyl.
Dependencies are inferred from the claim text.