Abstract: A base resistant, substantially amorphous fluoroelastomer comprising (1) 10-40 mole percent ethylene units, (2) 32-60 mole percent tetrafluoroethylene units, (3) 20-40 mole percent perfluoro ether units selected from the group consisting of perfluoro(alkyl vinyl ethers), perfluoro(alkyl alkenyl ethers) and perfluoro(alkoxy alkenyl ethers), and (4) 0.1 to 15 mole percent of a cure site monomer selected from the group consisting of i) 3,3,3-trifluoropropene-1, ii) trifluoroethylene, iii) 1,2,3,3,3-pentafluoropropylene, iv) 1,1,3,3,3-pentafluoropropylene, and v) 2,3,3,3-tetrafluoropropene. Such fluoroelastomers may be vulcanized with polyhydroxy curatives. The resulting vulcanized fluoroelastomer compositions are resistant to attack by amines, strong bases and hydrogen sulfide and possess a combination of good low temperature and high temperature properties and they are resistant to oil swell.
Type:
Grant
Filed:
May 2, 2002
Date of Patent:
December 16, 2003
Assignee:
DuPont Dow Elastomers LLC
Inventors:
Walter Werner Schmiegel, Phan Linh Tang
Abstract: Peroxide curable fluoroelastomers having copolymerized units of vinylidene fluoride or tetrafluoroethylene major monomer, at least one other fluorinated major monomer, a cure site monomer having the general formula CH2═CH—(CF2)nI, where n is an integer between 2 and 8, and iodine bound at the terminal positions of polymer chains, process well and have excellent tensile properties.
Abstract: Perfluoroelastomer compositions comprising perfluoroelastomers having copolymerized units of tetrafluoroethylene, a perfluoro(vinyl ether), and a nitrile-containing cure site monomer are cured with certain nitrogen-containing nucleophilic compounds. The nucleophilic compounds also act as dual curatives in perfluoroelastomer compositions which incorporate other curing agents.
Type:
Grant
Filed:
February 6, 2001
Date of Patent:
October 28, 2003
Assignee:
DuPont Dow Elastomers LLC.
Inventors:
Christopher John Bish, Peter Arnold Morken, Walter Werner Schmiegel
Abstract: Ethylene-based polymer blends having an MWD of at least about 2 are made in a single reactor using a mixed constrained geometry catalyst (CGC) system. The process comprises the steps of contacting under polymerization conditions and in a single reaction vessel (i) ethylene, (ii) at least one C3-C20 &agr;-olefin, (iii) optionally, at least one polyene, and (iv) a mixed CGC system.
Type:
Grant
Filed:
January 3, 2002
Date of Patent:
August 26, 2003
Assignee:
DuPont Dow Elastomers LLC
Inventors:
Michael K. Laughner, Debra J. Mangold, Deepak R. Parikh
Abstract: A recyclable, thermoplastic, two-phase polymer composition that includes a continuous thermoplastic polyurethane matrix phase and a soft, finely dispersed phase based on an ethylene copolymer that is normally thermodynamically incompatible with the thermoplastic polyurethane. The soft phase includes the product of a co-crosslinking reaction between the ethylene copolymer and a reactive plasticizer such as epoxidized linseed oil.
Abstract: Ethylene-based polymer blends having an MWD of at least about 2 are made in a single reactor using a mixed constrained geometry catalyst (CGC) system. The process comprises the steps of contacting under polymerization conditions and in a single reaction vessel (i) ethylene, (ii) at least one C3-C20 (&agr;-olefin, (iii) optionally, at least one polyene, and (iv) a mixed CGC system.
Type:
Grant
Filed:
August 14, 2000
Date of Patent:
April 9, 2002
Assignee:
DuPont Dow Elastomers LLC
Inventors:
Michael K. Laughner, Debra J. Mangold, Deepak R. Parikh
Abstract: A fluoroelastomer latex is produced that is capable of forming films having excellent water resistance. In a first step, polymerization of fluorinated monomers is carried out in the presence of fluorinated surfactants at a pH of 3-8. The pH of the resultant fluoroelastomer emulsion composition is then adjusted to 5-9 and the emulsion is concentrated to yield a solids-rich latex.