Fina Technology, Inc.

Lisa Albe

Scott Cooper

Cyril Chevillard

Jay Nguyen

Mohan R Gownder

Darek Wachowicz

Pamela Lawyer

A thermoformed polypropylene article, or sheet for preparing such articles, is formed from a layer of substantially syndiotactic polypropylene and a thin outer layer of substantially isotactic polypropylene that is joined to the layer of syndiotactic polypropylene. At least one of the layers is a non-oriented layer. Two layers of isotactic polypropylene may be used with the layer of syndiotactic polypropylene, so that the syndiotactic polypropylene is sandwiched between the two layers of isotactic polypropylene. The use of the isotactic polypropylene enhances the processability of the syndiotactic polypropylene, which is oftentimes difficult to process because of its lower melting point and slow solidification rate. Because the sheet is comprised predominantly of syndiotactic polypropylene, utilizing only thin outer layers of isotactic polypropylene, it has better transparency and higher impact strength than those conventional articles formed entirely of isotactic polypropylene.

Polypropylene article and method of preparing polypropylene article

Process for the production of an alpha olefin polymer and a process for the treatment of the alpha olefin polymer. A polymerization feed containing an alpha olefin, such as propylene, is supplied to the reactor to produce a thermoplastic polymer product involving a homopolymer or a copolymer. A product stream containing the polymer is withdrawn from the polymerization reactor and the polymer product is recovered from the product stream. The polymer product is then processed to produce the polymer product in a granular or pelletized form. A hindered amine light stabilizer is oxidized with an oxidizing agent under conditions to convert at least a portion of the amine groups to nitroxyl groups. The oxidized hindered amine light stabilizer is then supplied to the polymer product prior to heating and processing of the polymer product.

Polymerization process

Process for the production of fibers formed from an ethylene-propylene copolymer characterized as a random copolymer of ethylene and isotactic polypropylene having a random ethylene content within the range of 2-12 mole %. The propylene content of the copolymer can have an isotacticity of at least 90% meso diads. The copolymer is heated to a molten state and then extruded to form a fiber preform. The fiber preform is subject to a spinning speed of at least 500 meters per minute. This is followed by drawing the spun fiber preform at a draw ratio within the range of 1:1-6:1 to produce a continuous fiber of the ethylene-propylene copolymer. A specific ethylene-propylene copolymer has an ethylene content within the range of 6-8%.

Polypropylene fibers

A fiber product drawn from an isotactic propylene copolymer of a C , C , C , C , C or C &agr;-olefin monomer produced in the presence of a metallocene catalyst characterized by a bridged chiral and stereorigid cyclopentadienyl or substituted cyclopentadienyl ligand structure of a transitional metal selected from group 4b, 5b, or 6b metals of the Periodic Table of Elements, the copolymer having a MFR less than 35, suitably about 30 or less. The copolymer is heated to a molten state and extruded to form a fiber preform. The preform is subjected to spinning at a spinning speed of at least 300 meters per minutes and subsequent drawing at a speed of up to about 1500 meters per minute to provide a draw ratio of at least 1.5 up to 5:1 to produce a continuous fiber having high tenacity of about 3.5 grams per denier and greater and good hand.

Metallocene catalyzed propylene-&agr;-olefin random copolymer melt spun fibers

A process for the production and treatment of a stereoregular polypropylene, such as isotactic polypropylene in which a polymerization reactor is operated under conditions to react propylene supplied to the reactor to produce a stereoregular propylene polymer fluff. A product stream containing the fluff and unreacted propylene is withdrawn from the reactor and at least a portion of the unreacted propylene is separated from the product stream. The propylene polymer fluff is heated to a temperature sufficient to melt the propylene polymer, and a lactone is incorporated into the propylene polymer. The lactone is a 5,7 dialkyl-3-(2,3 dialkyl phenyl)-3H-benzofuran-2-one, in which the 5,7 and 2,3 substituents are of relatively low molecular weights. The phenyl alkyl substituents, each contain 1 or 2 carbon atoms, and the 5,7 alkyl substituents each contain from 2 to 5 carbon atoms. After the heating and incorporation of the lactone, the heated polymer fluff containing the lactone is extruded to produce particles of the propylene polymer. The polymer particles containing the lactone can be heated to a molten state and then extruded to form a fiber preform. The fiber preform is subject to spinning and drawing at differential spinning and drawing speeds to provide a draw ratio sufficient to form a continuous polypropylene fiber.

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Houston, TX, United States of America

Lisa Albe