Equistar Chemicals, LP

Basell Polyolefine Gmbh

Sameer D Mehta

Harilaos Mavridis

Gerhardus Meier

Bernd Lothar Marczinke

Chun D Lee

Ulf Schueller

Mark K Reinking

Elke Damm

Harald Schmitz

Andreas Maus

Philip J Garrison

Edward S Vargas

Venki Chandrashekar

Eric D Day

Sebastian Wilhelm

Michael W Lynch

Charles S Holland

Vu Anh Dang

Mark P Mack

Douglas D Klendworth

Jeffrey Charles Haley

Steven W Horwatt

Jeffrey S Borke

Dinshong Dong

Jeffrey J Strebel

Jeffrey A Jones

Anthony J De Nicola, Jr

Manivakkam J Shankernarayanan

James R Beren

Richard J Fezza

Jeffrey C Haley

Manivakkam J Shankernarayan

Ndiba N Dioh

A polyethylene composition particularly suited for producing blow-molded hollow articles, having the following features:

Polyethylene composition for blow molding having an improved swell behavior

The present disclosure relates to pipes comprising bimodal high molecular weight high density polyethylene which has been extruded in the presence of one or more organic peroxides that are present in an amount ranging from 30 ppm to 200 ppm. The pipe has an improved long-term hydrostatic strength. Also provided are methods for preparing pipes having these characteristics.

Low-sag polyethylene pipes and methods thereof

Disclosed is a polyethylene composition having faster crystallization rate and improved environmental stress cracking resistance. The polyethylene composition comprises a multimodal polyethylene and a nucleating agent. The multimodal polyethylene comprises from 25 to 50 wt % of a low molecular weight ethylene homopolymer component, from 25 to 50 wt % of a medium molecular weight ethylene copolymer component and from 25 to 50 wt % of a high molecular weight ethylene copolymer component. The polyethylene composition has an environmental stress cracking resistance (ASTM D1693, Condition B in 100% Igepal) greater than or equal to 40 days and a crystallization half time less than or equal to 70% of the crystallization half time of the multimodal polyethylene without nucleating agent.

Polyethylene having faster crystallization rate and improved environmental stress cracking resistance

The present invention relates to a process comprising extruding a blend of an first propylene polymer comprising a non-phenolic stabilizer and a non-irradiated second propylene polymer, wherein the irradiation of the first propylene polymer was conducted in a reduced oxygen environment, and the irradiated first propylene polymer and the non-irradiated second propylene polymer were blended at a temperature below the melting point of the first and second propylene polymers.

Extrusion processes using high melt strength polypropylene

Disclosed is a multimodal, high density, homopolyethylene barrier resin. The resin is preferably made by a multistage process. The process comprises a first stage in which ethylene is homopolymerized in the presence of a Ziegler-Natta catalyst, organoaluminum cocatalyst, alkoxysilane modifier, and hydrogen. The reaction mixture from the first stage is devolatilized to remove all or substantially all of the hydrogen. The polymerization continues in a second stage wherein ethylene is added to the devolatilized reaction mixture to produce the barrier resin. The barrier resin provides films with improved barrier properties.

Preparation of multimodal, high density, ethylene homopolymer barrier resins and films

Filled propylene polymer compositions having significantly improved melt strength are provided. The compositions are blends of propylene polymer, mineral filler with an ethylene polymer component consisting of an ethylene plastomer and a silane-containing ethylene polymer.

Filled propylene polymer compositions having improved melt strength

Cellulosic-reinforced composites having increased resistance to water absorption are provided. The improved composites are obtained using a mixture of high density polyethylene and silane copolymer with the cellulosic filler.

Cellulosic-reinforced composites having increased resistance to water absorption

Resins comprising a relatively high-density, low-molecular-weight polyethylene component and a relatively low-density, high-molecular-weight ethylene copolymer component and methods of making the resins are disclosed. The rheological polydispersity of the high-density component exceeds that of either the resin or the low-density component. The resins are valuable for making films, sheets, coatings, pipes, fibers, and molded articles having a favorable balance of good stiffness and excellent environmental stress crack resistance.

Polymer resins with improved environmental stress crack resistance

Ethylene polymer composites, concentrates and a process utilized for their preparation are provided. The composites of the invention have increased melt strength compared to the base resin and other improved physical characteristics. The composites contain an organically modified clay and may also contain a compatibilizng agent, depending on the base resin used.

Process for increasing the melt strength of ethylene-vinyl carboxylate copolymers

A process for copolymerizing ethylene with vinylsilanes is disclosed. The process uses a Ziegler-Natta catalyst and cocatalyst wherein the Ziegler-Natta catalyst is prepared from a Group 4-6 halogen-containing transition metal and a mixture of an organomagnesium compound and a silicon-containing compound. Silane-functionalized polyolefins produced using the process can be crosslinkable and can be used to bond polyolefins to polysiloxanes or other functionalized polymers.

Process for copolymerizing ethylene with vinylsilanes

Ethylene polymer composites and concentrates utilized for their preparation are provided. The composites of the invention have increased melt strength compared to the base resin and other improved physical characteristics. The composites contain an organically modified clay and may also contain a compatibilizng agent, depending on the base resin used.

Ethylene polymer compositions having improved melt strength

A process for producing olefin polymer composites having improved melt strength and other improved physical characteristics is provided. The process is a solution process wherein an organically modified clay is intimately incorporated, at low levels and without the use of compatibilizing agents, into an olefin polymer base resin.

Process for producing olefin polymer composites having improved melt strength

A blend comprising a high molecular weight, high density polyethylene (HMW HDPE) and a linear low density polyethylene (LLDPE) is disclosed. The blend comprises from about 50 wt. % to about 80 wt. % of HMW HDPE. The HMW HDPE has a density greater than about 0.94 g/cc and a melt index MI less than about 0.1 dg/min. The blend also comprises about 20 wt. % to about 50. wt % of LLDPE. The LLDPE has a density within the range of about 0.90 to about 0.93 g/cc and an MI within the range of about 0.5 to about 5 dg/min. The LLDPE is a copolymer of ethylene with 1-hexene that has a dart drop impact strength of greater than about 500 grams as measured by ASTM D1709/A. The blend shows increased resistance to environmental stress cracking.

Polyethylene blends

Propylene polymer composites containing modified clays and compatibilizing agents, more specifically hydrogenated tallow modified montmorillonite and maleic anhydride grafted propylene polymers, are provided. Concentrates or masterbatches used to prepare the composites are also described. The improved composites of the invention exhibit increased melt strength compared to the base resin and to composites similarly formulated using other types of modified clays. Moreover, the improved results are achievable at lower compatibilizer levels and lower ratios of compatibilizer to clay than has heretofore been considered practical.

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Mason, OH, United States of America

Sameer D Mehta