EXTRUDIERTE FOLIE AUS EINER IN-SITU MISCHUNG VON ETHYLENCOPOLYMEREN

• Main Authors: MICHIE, WILLIAM JAMES JR, ST. JEAN, GUYLAINE, RICKMAN-DAVIS, DIANE JEAN, EALER, GEORGE EDWARD, SAKEVICH, CHARLES JOHN
• Format: Patent
• Language: German
• Published: 15.03.2004
• Edition: 7
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

A film comprising a blend of copolymers, which has been extruded (i) to a film having a gauge of less than about 1.8 mils; a dart impact strength of at least about 80 grams per mil at a density of 0.926 gram per cubic centimeter; and a dart impact strength of at least about 480 grams per mil at a density of 0.918 gram per cubic centimeter and/or (ii) to a film having a gauge of less than about 5 mils, and a blocking force of less than about 120 grams and a COF in the range of about 0.2 to about 0.5, said blend having been produced in situ by contacting ethylene and at least one alpha-olefin comonomer with a magnesium/titanium based catalyst system in each of two reactors connected in series, under polymerization conditions, wherein the polymer formed in the high molecular weight reactor has a flow index in the range of about 0.01 to about 30 grams per 10 minutes and a density in the range of about 0.860 to about 0.940 gram per cubic centimeter and the polymer formed in the low molecular weight reactor has a melt index in the range of about 50 to about 3000 grams per 10 minutes and a density in the range of about 0.900 to about 0.970 gram per cubic centimeter, the weight ratio of high molecular weight reactor polymer to low molecular weight reactor polymer being in the range of about 0.5:1 to about 2:1 with the proviso that for film (i), 1-butene is at least one of the comonomer(s) used in the low molecular weight reactor and is present in the in situ blend in a weight ratio of 1-butene to the other comonomer(s) in the range of about 0.001:1 to about 1.3:1, and for film (ii), the film is essentially free of antiblock and slip agents.