Abstract: The invention concerns a certain class of polymers, their production into films and applications for their use. These polymers have unique properties which make them particularly well suited for use in polymeric films. These films are very useful in applications requiring heat sealability, particularly those applications containing an ionomer film.It has been discovered that polymers derived from metallocene catalyst systems surprisingly heat seal extremely well, as compared to polymer produced by conventional Ziegler-Natta catalysts, to a class of polymers known as ionomers.
Type:
Grant
Filed:
August 20, 1993
Date of Patent:
October 31, 1995
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Richard W. Halle, Donna S. Davis, Charles R. Harris, Jr.
Abstract: Disclosed is an elastic film having improved properties. The elastic film can be blown, cast or cast embossed. The elastic film is processed by polymerizing olefins in the presence of a metallocene catalyst system.
Type:
Grant
Filed:
July 14, 1993
Date of Patent:
September 19, 1995
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Thomas C. Erderly, Aspy K. Mehta, Jeffrey A. Middlesworth
Abstract: This invention relates to a process for transitioning between incompatible polymerization catalyst systems. Particularly, the invention relates to a process for transitioning from an olefin polymerization reaction utilizing a traditional Ziegler-Natta catalyst system to a metallocene-olefin polymerization reaction.
Type:
Grant
Filed:
March 25, 1994
Date of Patent:
August 15, 1995
Assignee:
Exxon Chemical Company
Inventors:
Agapios K. Agapiou, Michael E. Muhle, Gary T. Renola
Abstract: The invention is directed toward polymerizing or copolymerizing alpha-olefins either alone or in combination with one or more other alpha-olefins in a gas phase reactor having a fluidized bed and a fluidizing medium such that the fluidizing medium entering the reactor comprises a gas and a liquid phase.
Abstract: This invention is generally directed toward a supposed catalyst system useful for polymerizing olefins. The method for supposing the catalyst of the invention provides for a supposed metallocene catalyst able to produce polymers having broader molecular weight distribution and a higher molecular weight. Not only are such polymers easily processable as compared with metallocene polymers produced with other support methods but the methods of this invention provides for a supposed catalyst with increased activity.
Abstract: The invention is directed toward polymerizing alpha-olefins either alone or in combination with one or more other alpha-olefins utilizing a bulky ligand transition metal catalyst in a gas phase fluidized bed polymerization reactor operating in condensed mode.
Type:
Grant
Filed:
March 22, 1994
Date of Patent:
April 11, 1995
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Marc L. DeChellis, John R. Griffin, Michael E. Muhle
Abstract: Linear interpolymer blends are disclosed. The blends are made from components having a narrow molecular weight distribution (e.g. Mw/Mn.ltoreq.3) and a narrow composition distribution (e.g. CDBI>50%). The blend components of the blend can all have the same molecular weight but different comonomer contents, the same comonomer content but different molecular weights, or comonomer contents which increase with molecular weight. The blends have either Mw/Mn>3 and/or CDBI<50%, and combinations of each, and can be bimodal with respect to either or both molecular weight and/or comonomer content. The blends are generally free of blend components having both a higher average molecular weight and a lower average comonomer content than another blend component. The blends can have improved mechanical, physical and/or chemical properties. Single or multilayer films having enhanced physical properties are made from the blends.
Type:
Grant
Filed:
June 4, 1993
Date of Patent:
January 17, 1995
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Ferdinand C. Stehling, Charles S. Speed, Howard C. Welborn, Jr., deceased
Abstract: Linear ethylene interpolymer blends are disclosed. The blends are made from components having a narrow molecular weight distribution (e.g. M.sub.w /M.sub.n .ltoreq.3) and a narrow composition distribution (e.g. CDBI>50%). The blend components in a blend can all have the same molecular weight but different comonomer contents, the same comonomer content but different molecular weights, or comonomer contents which increase with molecular weight. The blends have either M.sub.w /M.sub.n >3 or CDBI<50%, or both, and can be multimodal with respect to either or both molecular weight and/or comonomer content. The blends are generally free of blend components having both a higher average molecular weight and a lower average comonomer content than another blend component. The blends can have improved mechanical, physical and/or chemical properties.
Type:
Grant
Filed:
February 4, 1993
Date of Patent:
January 17, 1995
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Ferdinand C. Stehling, Charles S. Speed, Curtis H. Welborn, Jr.
Abstract: The present invention provides for a polymer composition comprising a blend of from about 25 to about 90% by weight of a very low density ethylene polymer having a density on the range of from about 0.88 to 0.925 g/cm.sup.3, a melt index of from about 0.5 to about 7.5 dg/min, a molecular weight distribution not greater than about 3.5 and a compositional distribution breadth index greater than about 70%, and from about 10 to about 75% by weight of a low to medium density ethylene polymer having a density of from about 0.910 to about 0.935, a melt index of from about 0.5 to about 20, a molecular weight distribution greater than about 3.5 and a compositional breadth index less than about 70%.The invention also provides for films prepared from this blend having single layer construction or having laminar ABA construction wherein the A or skin layers comprise the blend of this invention and the B or core layer comprises a different olefin polymer such as high density polyethylene.
Type:
Grant
Filed:
March 29, 1994
Date of Patent:
December 27, 1994
Assignee:
Exxon Chemical Patents Inc.
Inventors:
William J. Hodgson, Richard W. Halle, Charles L. Pierce
Abstract: This invention relates to a supported catalyst composition useful in the polymerization of olefins and to a method for its production. The invention particularly relates to the use of undehydrated silica gel containing from about 6 to about 20 per cent by weight adsorbed water as the catalyst support material. The catalyst is formed by first reacting a trialkylaluminum compound with a metallocene, and subsequently reacting the resulting material with the undehydrated silica gel. The resulting supported metallocene-alumoxane catalyst has a level of activity comparable to that of conventionally made supported catalysts which are achieved at active metal loadings which are reduced from the loadings used in the previously known metallocene-alumoxane catalysts by at least 20%, and preferably 50%.
Abstract: An improved catalyst system and process of producing polyolefins having a controllable broadened molecular weight distribution utilizing transition metal metallocene catalyst systems, wherein at least one of the metallocenes has at least one cyclopentadienyl ring being substituted by at least one optionally substituent having a 2.degree. or 3.degree. carbon atom with which it is covalently bonded to the cyclopentadienyl ring. The method for forming the catalyst system of this present invention can be either by a physical or a chemical mixing process.
Abstract: Disclosed are heat sealable compositions comprising: (a) from about 30 to about 70 weight percent a low melting polymer comprising an ethylene based copolymer having a density of from about 0.88 g/cm.sup.3 to about 0.915 g/cm.sup.3, a melt index of from about 1.5 dg/min to about 7.5 dg/min, a molecular weight distribution no greater than about 3.5, and a composition breadth index greater than about 70 percent; and, (b) from about 70 to about 30 weight percent of a propylene based polymer having from about 88 mole percent to about 100 mole percent propylene and from about 12 mole percent to about 0 mole percent of an alpha-olefin other than propylene. Further disclosed are films and articles made thereof.
Abstract: The invention is directed toward polymerizing or copolymerizing alpha-olefins either alone or in combination with one or more other alpha-olefins in a gas phase reactor having a fluidized bed and a fluidizing medium such that the fluidizing medium entering the reactor comprises a gas and a liquid phase.
Abstract: A catalyst and method of producing polyolefins having broadened molecular weight distributions and enhanced tensile impact strengths utilizing a silica supported metallocene-alumoxane catalyst system, wherein at least one of the metallocenes has at least one cyclopentadienyl ring being substituted by at least one optionally substituted hydrocarbon substituent having a 2.degree. or 3.degree. carbon atom with which it is covalently bonded to the cyclopentadienyl ring.
Abstract: A seal layer for use in heat sealed containers, especially retortable polymer containers. A semirigid or rigid packaging container with a multilayer laminate heat sealed to a tray flange, the laminate having a barrier layer and the lidding being easily opened by cohesive failure of a layer containing as elastomer. The elastomer is preferably PIB in a heat seal film layer on a polypropylene tray.
Abstract: Disclosed are electrically conductive and semiconductive devices utilizing polymers having resistance to water treeing and good dielectric properties. The polymer comprises ethylene polymerized with at least one C.sub.3 to C.sub.20 alpha-olefin and optionally at least one C.sub.3 to C.sub.20 polyene. The polymer utilized has a density in the range of about 0.86 g/cm.sup.3 to about 0.96 g/cm.sup.3, a melt index in the range of about 0.2 dg/min to about 100 dg/min, a molecular weight distribution in the range of about 1.5 to about 30, and a composition distribution breadth index greater than about 45 percent. For the polymer utilized, the tree rating is generally less than about 40, the power factor is in the range of about 0.0002 to about 0.0005, and the dielectric constant is in the range of about 1.8 to about 2.4.
Type:
Grant
Filed:
August 15, 1991
Date of Patent:
September 21, 1993
Assignee:
Exxon Chemical Patents Inc.
Inventors:
Lawrence Spenadel, Monica L. Hendewerk, Aspy K. Mehta
Abstract: Disclosed is a process for improving the unload power of a precursor elastic film comprising orienting the film to a draw ratio in the range of about 2:1 to about 20:1 followed by annealing. Further disclosed is an elastic film oriented to a draw ratio in the range of about 2:1 to about 20:1 and comprising a copolymer of ethylene polymerized with at least one comonomer selected from the group consisting of C.sub.3 to C.sub.20 alpha-olefins and C.sub.3 to C.sub.20 polyenes, wherein the copolymer has a density in the range of about 0.855 g/cm.sup.3 to about 0.9 g/cm.sup.3, a melt index in the range of about 0.5 to about 50, with a composition distribution index at least about 45 percent.
Abstract: This invention relates to a supported catalyst composition useful in the polymerization of olefins and to a method for its production. The invention particularly relates to the use of undehydrated silica gel containing from about 6 to about 20 percent by weight adsorbed water as the catalyst support material. The catalyst is formed by first reacting a trialkylaluminum compound with a metallocene, and subsequently reacting the resulting material with the undehydrated silica gel. The resulting supported metallocene-alumoxane catalyst has a level of activity comparable to that of conventionally made supported catalysts which are achieved at active metal loadings which are reduced from the loadings used in the previously known metallocene-alumoxane catalysts by at least 20%, and preferably 50%.
Abstract: The invention provides laminar polyolefin film materials having a base film layer comprising a blend of an olefin polymer and up to about 30% by weight of at least one very low density copolymer of ethylene and a C.sub.3 to C.sub.20 alpha olefin comonomer copolymerizable with ethylene, said base layer having a heat sealable film layer present on one or both surfaces thereof comprising a very low density copolymer of ethylene and a copolymerizable C.sub.5 to C.sub.12 alpha olefin comonomer. The ethylene copolymer constituents of the film are characterized as having a density in the range of about 0.88 g/cm.sup.3 to abut 0.915 g/cm.sup.3, a melt index in the range of about 0.5 dg/min to about 7.5 dg/min, a molecular weight distribution (M.sub.w /M.sub.n) of about 1.5 to about 3.5 and an essentially single melting point in the range of about 60.degree. C. to about 115.degree. C., measured as a DSC peak T.sub.m.
Abstract: A conduit for receiving lengths of fiber optical cable, which enhances light emission and transmission within the cable by substantially reducing an air gap located between a polymeric core and an outer cladding of the fiber optical cable. The conduit of the present invention has a retaining member that defines a first channel adapted to receive the fiber optical cable and a base member that defines a second channel adapted to receive the cable. The retaining member is mounted with the base member, such that the cable is retained within the first and the second channels and a compressive force is exerted on the cable, which substantially eliminates the gap between the core and outer cladding. Furthermore, the conduit of the present invention supports and guides the cable and facilitates the installation thereof.