Abstract: Gas leakage from a high pressure compressor used in providing olefin monomer feed to a high pressure polymerization reactor is minimized by the addition of an antioxidant to the cylinder lubrication fluid to provide an antioxidant concentration of from about 3 wt % to about 10 wt %.

Abstract: Heat-sterilizable films are made from a polymer blend of about 10 to about 60 wt % random propylene-ethylene copolymer containing from about 1 to about 6 wt % ethylene-derived units and about 40 to about 90 wt % linear low density polyethylene. The films are especially useful in the manufacture of collapsible parenteral solution bags and overwraps.

Abstract: Heat-sterilizable films are made from a polymer blend of about 10 to about 60 wt % random propylene-ethylene copolymer containing from about 1 to about 6 wt % ethylene-derived units and about 40 to about 90 wt % linear low density polyethylene. The films are especially useful in the manufacture of collapsible parenteral solution bags and overwraps.

Abstract: The invention provides an additive-containing polyolefin having an inner bead of a first polyolefin and an outer adherent coating of a second polyolefin encapsulating the additive.

Abstract: High clarity propylene polymer compositions having improved impact strength are comprised of a blend of a random copolymer of propylene and ethylene, containing from about 1 to about 6 wt % polymerized ethylene, with a linear low density polyethylene in a weight ratio range between about 80:20 and about 95:5. The linear low density polyethylene is a copolymer of ethylene and a C.sub.4 -C.sub.18 alpha-olefin and has a density in the range from about 0.910 to about 0.935 gms/cc.

Abstract: A process for the high pressure polymerization of ethylene in a reactor in the presence of conventional free radical generating initiators, wherein the initiator material is admixed with certain additives in small concentrations to lower the polymerization initiation temperature.

Abstract: Films especially useful for the stretch wrapping of pallet loads are prepared from compositions consisting essentially of a linear low density polyethylene resin free of any polymerized vinyl acetate groups and from about 0.3 to about 3.0 wt % sorbitan monooleate based on the weight of the resin.

Abstract: Polyolefin resins are rendered stable against degradation caused by exposure to heat and oxygen in the presence of copper by the incorporation of a novel polymeric stabilizer functioning dually as an antioxidant and a chelating agent.

Abstract: In a high pressure tubular reactor containing a plurality of tubular sections interconnected in series by means of connection devices, which reactor contains one or more reaction zones, there is positioned within each reaction zone a single rupture disc device from about 24 to about 40 feet downstream from the reaction zone inlet. A particularly suitable rupture disc-connection block device is disclosed.

Abstract: The polymerized ethylene content of a copolymer of ethylene and propylene is enhanced without lowering the isotacticity of the copolymer when the polymerization is conducted in the presence of small amounts of butene-1.

Abstract: Propylene polymers of improved melt flow characteristics are obtained in a liquid pool propylene polymerization process carried out in the presence of a magnesium halide supported titanium halide-aluminum trialkyl catalyst system, where prior to its introduction to the polymerization reactor, the magnesium halide supported titanium halide catalyst component is admixed with an aromatic carboxylic acid ester electron donor and the mixture is subsequently introduced into the poymerization zone no later than about 5 days from the time of admixing.

Abstract: A process for the preparation of ethylene-propylene block copolymers at improved catalyst productivity rates involving the formation of a propylene prepolymer by polymerization of propylene in liquid phase in the presence of a catalyst system containing titanium halide supported on magnesium halide and aluminum alkyl complexed with an electron donor. Ethylene and propylene are block polymerized onto the prepolymer in a vapor phase reaction zone in the presence of further added quantities of similar catalyst components. The product of the process has higher ethylene and block contents as compared to products formed with none or only one of the components being added to the vapor phase reaction zone.

Abstract: Polyolefin resin pellets of greater uniformity of shape and characterized by an almost complete absence of tails are obtained by the use in the pelletizing apparatus of dies which have been coated by a thin layer of finely divided solid lubricant such as molybdenum disulfide or, preferably, graphite applied to the interior surfaces of the die by cross bombardment with a stream or streams of finely divided solid lubricant under pressure.

Abstract: A process for the preparation of ethylene-propylene block copolymers at high catalyst productivity rates resulting in polymer products having improved impact strength-polymerized ethylene content relationship.

Abstract: Polyolefin resins are rendered stable against degradation caused by exposure to heat and oxygen in the presence of copper by the incorporation of a novel polymeric stabilizer functioning dually as an antioxidant and a chelating agent.

Abstract: A process for the preparation of ethylene-propylene block copolymers at high catalyst productivity rates resulting in polymer products having improved impact strength-polymerized ethylene content relationship. The improvement is obtained by reacting preformed propylene prepolymer still containing active catalyst residues with ethylene and propylene in a vapor phase reaction zone in the presence of additional aluminum trialkyl catalyst component introduced to the reaction zone. The polymer produced by the process exhibits excellent physical and mechanical properties.

Abstract: A process for the preparation of ethylene-propylene block copolymers at high catalyst productivity rates resulting in polymer products having improved impact strength-polymerized ethylene content relationship.

Abstract: Polyolefin resins are rendered stable against degradation caused by exposure to heat and oxygen in the presence of copper by the incorporation of a novel polymeric stabilizer functioning dually as an antioxidant and a chelating agent.

Abstract: In a high pressure tubular reactor containing a plurality of tubular sections interconnected in series by means of connection devices, which reactor contains one or more reaction zones, there is positioned within each reaction zone a single rupture disc device from about 24 to about 40 feet downstream from the reaction zone inlet.

Abstract: An improved lubrication system is provided for the cylinder of a reciprocatory plunger rod compressor, having a stationary annular seal assembly around said plunger rod. The key feature of this system resides in the incorporation of check valves in lubricant supply passages located internally within the seal assembly surrounding the plunger rod. Preferably, said check valves are located within suitable recesses bored into the rear face of an interior packing cup element of said seal assembly. The use of such internal lubricant check valves protects the lubricator quills, fittings, and other components of the lubrication system against fatigue failures and lengthens the continuous on-line operating life of the entire lubrication system.