Abstract: Multimodal polyethylene resins having improved stress crack resistance and melt strength rendering them useful for the manufacture of thick-walled pipe are produced in a process wherein the second stage of the process is a copolymerization conducted at a high temperature with a low comonomer to ethylene ratio and a low hydrogen to ethylene ratio.

Abstract: Bimodal polyethylene resins having reduced long-chain branching and suitable for use in pipe resin applications as a result of their improved SCG and RCP resistance are provided. The improved resins of the invention are produced in a two-reactor cascade slurry polymerization process using a Ziegler-Natta catalyst system and wherein an alkoxysilane modifier is present in both reactors.

Abstract: A slurry process for polymerizing ethylene is disclosed. The process comprises polymerizing ethylene in a first reactor in the presence of hydrogen and a catalyst comprising an activator and a supported dimethylsilyl-bridged indeno[1,2-b]indolyl zirconium complex to produce an ethylene homopolymer, removing some of the unreacted hydrogen, and reacting the homopolymer slurry in a second reactor with ethylene and a C3-C10 ?-olefin to produce polyethylene. The polyethylene has weight-average molecular weight greater than 150,000, broad molecular weight distribution, low long-chain branching, and it provides pipes or molded articles with good environmental stress crack resistance.

Abstract: Resin blends useful for pipe and blow-molded articles are disclosed. The blends comprise a low-molecular-weight, high-density polyethylene and a high-molecular-weight, low-density ethylene copolymer. The high-molecular-weight component is made with a bridged indenoindolyl Group 4 metal complex having open architecture. Blends of the invention uniquely have high molecular weight (Mw>200,000) and low levels of long-chain branching. A quick, convenient approach for estimating levels of long-chain branching in polyethylenes from gel permeation chromatography and dynamic oscillatory rheometry (“viscosity enhancement factor”) is disclosed.

Abstract: Flame retardant crosslinkable polyolefin compositions useful for the production of films, sheets and membranes are provided. The compositions are comprised of ethylene-silane copolymer, plastomer, flame retardant filler and, optionally, silanol condensation catalyst.

Abstract: Flame retardant crosslinkable polyolefin compositions useful for the production of films, sheets and membranes are provided. The compositions are comprised of ethylene-silane copolymer, plastomer, flame retardant filler and, optionally, silanol condensation catalyst.

Abstract: High melt flow filled propylene polymer compositions suitable for injection molding are provided. The compositions are blends of propylene impact copolymer, high melt index plastomer and mineral filler.

Abstract: High melt flow filled propylene polymer compositions suitable for injection molding are provided. The compositions are blends of propylene impact copolymer, high melt index plastomer and mineral filler.