Chevron Phillips Chemical Company LP

Phillips Petroleum Company

John R Rathman

Yongwoo Inn

Carlos A Cruz

Jay M Chaffin

Qing R Yang

Mark L Hlavinka

Steven J Secora

Daniel G Hert

Donald L Peters

William M Whitte

Youlu Yu

Ashish M Sukhadia

Brandy Rutledge-Ryal

Jimmie L Dean

Jennifer L Hicks

Justin Lumbley

Rex L Bobsein

William R Coutant

Bryan E Hauger

Bryan Hauger

Irvin L Sumpter

Qing Yang

Ethylene-based polymers having a density of 0.952 to 0.965 g/cm, a high load melt index (HLMI) from 5 to 25 g/10 min, a weight-average molecular weight from 275,000 to 450,000 g/mol, a number-average molecular weight from 15,000 to 40,000 g/mol, a viscosity at HLMI from 1400 to 4000 Pa-sec, and a tangent delta at 0.1 secfrom 0.65 to 0.98 degrees. These polymers have the processability of chromium-based resins, but with improved stress crack resistance, and can be used in large-part blow molding applications.

Blow molding polymers with improved cycle time, processability, and surface quality

Ethylene-based polymers are generally characterized by a high load melt index of less than 12 g/10 min, a weight-average molecular weight from 200,000 to 550,000 g/mol, a number-average molecular weight from 18,000 to 48,000 g/mol, a CY-a parameter of less than 0.12, a tan &#x3b4; at 0.1 secfrom 0.5 to 0.9 degrees, a tan &#x3b4; at 100 secfrom 0.5 to 0.75 degrees, and a viscosity at 0.001 secfrom 1.3&#xd7;10to 1&#xd7;10Pa-sec. These ethylene polymers can be produced by peroxide-treating a bimodal molecular weight distribution dual metallocene-catalyzed resin, and can be used to produce blow molded bottles and other blow molded products.

Peroxide treated blow molding polymers with increased weight swell and constant die swell

Disclosed herein are ethylene-based polymers having a density greater than 0.945 g/cm, a high load melt index less than 25 g/10 min, a peak molecular weight ranging from 52,000 to 132,000 g/mol, and an environmental stress crack resistance of at least 250 hours. These polymers have the processability of chromium-based resins, but with improved impact strength and stress crack resistance, and can be used in large-part blow molding applications.

Polymers with improved toughness and ESCR for large-part blow molding applications

The whiteness and stability after processing of a polyolefin have been found to be improved upon the addition of a combination of at least one high activity phosphite and at least one hydrolytically stable phosphite.

Phosphite additives in polyolefins

A molding apparatus and method are adapted to mold an article having a hollow blow molded portion and a substantially solid compression molded portion. Defined within a mold is at least a first cavity portion and a second cavity portion. A parison is positioned within the mold and blow gas is injected into the interior of the parison to inflate the parison within each of the cavity portions. A compression member is then moved from a retracted position within a recess in the mold to an extended position outside of such recess. The compression member presses a first portion of the parison against the mold interior surface which defines the first cavity portion so as to compression mold a first portion of the parison. Inflation of a second portion of the parison in the second cavity portion accomplishes blow molding of such second parison portion.

Blow molding and compression molding of an article

A molding apparatus is provided which is operated to mold an article having a hollow blow molded portion and a substantially solid compression molded portion. A mold is provided which has defined therein at least a first cavity portion and a second cavity portion. A parison is positioned within the mold and blow gas is injected into the interior of the parison to inflate the parison within each of the cavity portions. A compression member is then moved from a retracted position within a recess in the mold to an extended position outside of such recess. The compression member presses a first portion of the parison against the mold interior surface which defines the first cavity portion so as to compression mold a first portion of the parison. Inflation of a second portion of the parison in the second cavity portion accomplishes blow molding of such second parison portion.

In blow molding an article with a reverse fold, a profiled bar is positioned where the parting line of the mold is to be when the mold is closed. The bar provides a reverse fold in the plastic article during a pre-blow step. In operation, a pre-pinched parison is formed adjacent the bar and as the mold begins to close a small amount of pre-blow air is introduced into the parison folding it against and over the bar. After the mold is closed, blow air is introduced to form the part. A complex part with good wall distribution of material can be obtained by this method.

Apparatus and method for blow molding

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Bartlesville, OK, United States of America

John R Rathman