Abstract: The present invention provides an ethylene copolymer resin that has unique melt elastic properties not observed in ethylene copolymers heretofore known. Specifically, the ethylene copolymer resin of the present invention when in pelletized form has a reduction in melt elasticity (ER) of 10% or more to a final value of 1.0 or less upon rheometric low shear modification or solution dissolution. Moreover, the resin of the present invention when in reactor-made form exhibits at least a partially reversible increase of 10% or more in ER when pelletizing the same. An ethylene polymerization catalyst, a process of preparing the ethylene copolymer resin and a high-impact film are also provided herein.

Abstract: Extrusion compositions having improved melt stability and suitable for use in high-speed extrusion coating operations are disclosed. The compositions are a dynamically modified mixture of a first polymeric component which is a reactor-made or physically blended mixture of polypropylene and an ethylene-propylene copolymer, a second polymeric component which is a fractional melt index homopolymer or copolymer of ethylene and an organic peroxide.

Abstract: The present invention provides an ethylene copolymer resin that has unique melt elastic properties not observed in ethylene copolymers heretofore known. Specifically, the ethylene copolymer resin of the present invention when in pelletized form has a reduction in melt elasticity (ER) of 10% or more to a final value of 1.0 or less upon rheometric low shear modification or solution dissolution. Moreover, the resin of the present invention when in reactor-made form exhibits at least a partially reversible increase of 10% or more in ER when pelletizing the same. An ethylene polymerization catalyst, a process of preparing the ethylene copolymer resin and a high-impact film are also provided herein.

Abstract: The instant invention is directed to a process for preparing peroxide modified polypropylene/polyethylene blends that have superior extrusion coating properties. More specifically, the peroxide modified PP/PE blends produced by the instant invention exhibit a pronounced viscosity upturn at low frequencies (about <1.0 rad/sec) in the dynamic rheological data. Specifically, the blends show an increase in their dynamic complex viscosity, .eta.*, and dynamic storage modulus, G' values at frequencies of less than about 1.0 rad/sec. The present invention also relates to peroxide modified PP/PE blends that are produced from the process of the instant invention. Such polymeric blends that are produced from the inventive method exhibit superior dynamic theological properties, especially melt strength, compared with prior art blends. Moreover, the peroxide modified PP/PE blends of the present invention show markedly reduced draw resonance behavior.

Abstract: A process is provided to improve the properties of polyethylene resins obtained from chromium catalyzed polymerizations and blow molded bottles produced therefrom. The process entails modifying the polyethylene resin by contacting the resin in a molten state with an organic peroxide at a temperature above the decomposition temperature of peroxide. Polyethylene resins utilized for the process have specific densities, melt indexes, long chain branching indexes, unsaturation contents and molecular weight distributions. Blow molded bottles produced from the modified resins have significantly increased top load stress crack resistance and improved swell characteristics.

Abstract: A die for a blow molding machine has at least one circumferential rectangular cutout section contiguous with the die exit in at least the die ring or the mandrel. The rectangular cutout section expands the material flow channel between the die ring and the mandrel to increase the volume flow of material passing through the die exit at the rectangular cutout section. However, the constant length of the rectangular cutout section in a longitudinal direction maintains a constant linear velocity of material flowing through the die exit.

Abstract: The present invention relates to a process for preparing high melt flow rate thermoplastic compositions that have improved impact and bruise-resistance properties and to the thermoplastic composition that are produced by the process of the instant invention. Specifically, the process comprises the steps of precontacting a non-crosslinked elastomeric polymeric component with a peroxide compound at a temperature below the decomposition temperature of the peroxide and below the melting point of the non-crosslinked polymeric component to produce a peroxide adsorbed polymeric component; and melt mixing the aforementioned peroxide adsorbed polymeric component with a high propylene content polymeric component selected from the group consisting of homopolymers of propylene, block copolymers of propylene and ethylene, and thermoplastic olefin polymers at a temperature above the decomposition temperature of the peroxide.