E.i. Dupont De Nemours and Company

Xerox Corporation

E. I. Du Pont Nemours and Co.

Philips & Du Pont Optical Company

Invista North America S.&aacute;.r.l.

The Chemours Company Fc, LLC

Kenneth Wayne Leffew

Jan M Stouffer

Elwood Neal Blanchard

Charles Joseph Noelke

Ralph Birchard Lloyd

Joseph D Trentacosta

Ralph Munson Aten

Vivek Kapur

John D Anthony, Jr

James R Larson

Govindasamy Paramasivam Rajendran

John M Iwasyk

David R Schiff

James E Geary, Jr

Thomas C Felder

Craig Robert Gochanour

David Peter Rule

Richard D Mules

Julie Anderson Rakestraw

Govindasamy Paramasivan Rajendran

Jill R Lorey

Andrew Robert Witt

Particles comprising a bulk of fluoropolymer and a nucleus of fluorinated ionomer, dispersions of such particles, articles and coatings made from such particles.

Fluoropolymer particles having a nucleus of fluorinated ionomer

A process for making an aqueous dispersion of fluorinated ionomer particles by providing dispersed particulate of fluorinated ionomer in an aqueous polymerization medium and polymerizing at least one fluorinated monomer having an ionic group in the aqueous polymerization medium in the presence of the dispersed particulate of fluorinated ionomer and initiator to form the aqueous dispersion of particles of fluorinated ionomer.

Fluorinated ionomer produced by aqueous polymerization using dispersed particulate of fluorinated ionomer

A process for making an aqueous dispersion of fluorinated ionomer particles by polymerizing in a first polymerization step at least one fluorinated monomer having an ionic group in an aqueous polymerization medium in the presence of initiator, the polymerizing providing dispersed particulate of fluorinated ionomer, polymerizing in a second polymerization step at least one fluorinated monomer having an ionic group in the aqueous polymerization medium in the presence of the dispersed particulate of fluorinated ionomer and initiator to form the aqueous dispersion of particles of fluorinated ionomer, and suspending the first polymerization step prior to beginning the second polymerization step.

Fluorinated ionomer produced by aqueous polymerization using dispersed particulate of fluorinated ionomer produced in situ

A process for making an aqueous dispersion of fluoropolymer particles by providing dispersed particulate of fluorinated ionomer in an aqueous polymerization medium and polymerizing at least one fluorinated monomer in the aqueous polymerization medium in the presence of the dispersed particulate of fluorinated ionomer and initiator to form the aqueous dispersion of particles of fluoropolymer.

Fluoropolymer produced by aqueous polymerization using dispersed particulate of fluorinated ionomer

A process for making an aqueous dispersion of fluoropolymer particles by polymerizing in a first polymerization step at least one fluorinated monomer having an ionic group in an aqueous polymerization medium in the presence of initiator, the polymerizing providing dispersed particulate of fluorinated ionomer, and polymerizing in a second polymerization step at least one fluorinated monomer in the aqueous polymerization medium in the presence of the dispersed particulate of fluorinated ionomer and initiator to form the aqueous dispersion of particles of fluoropolymer.

Fluoropolymer produced by aqueous polymerization using dispersed particulate of fluorinated lonomer produced in situ

A process for forming solid particles comprising the steps of: combining in molten form a major component of a crystallizable condensation homopolymer and a minor component of a non-crystallizable condensation polymer, wherein the crystallizable condensation homopolymer and the non-crystallizable condensation polymer each have a degree of polymerization of 10 to less than 48 prior to the combining; mixing the combined crystallizable condensation homopolymer and non-crystallizable condensation polymer in molten form to form a mixture that comprises 10 to 30 mol % of the non-crystallizable condensation polymer; forming the mixture into droplets; exposing the droplets to a thermal environment which results in the bulk of the droplet reaching within 15 seconds a temperature within &plusmn;10&deg; C. of the temperature at which the maximum rate of crystallization of the crystallizable condensation homopolymer occurs; and crystallizing at least a portion of the crystallizable condensation homopolymer in the mixture to form solid particles.

Process for crystallizing at least a portion of a crystallizable condensation homopolymer to form solid particles

A process for producing an oriented shaped article that comprises the steps of (a) forming a shaped article comprising a block copolymer comprising 75% to 90% by weight of polyethylene terephthalate blocks and 10% to 25% by weight of polyethylene isophthalate blocks and (b) biaxially stretching the shaped article to a planar stretch ratio of 10 to 30.

Process for producing an oriented shaped article

A process for increasing the rate of polymerization of low molecular weight polyester particles under solid state processing conditions whereby the progress of polymerization is preferred over the progress of crystallization for a given mass of particles.

Method for increasing solid state polymerization rate

Disclosed is an improved extrusion die assembly for controlling the flow of polymer in a melt extrusion process. The die assembly is useful for extruding low molecular weight polymer melts.

Extrusion die assembly

Disclosed herein is a novel physical form of low molecular weight poly(trimethylene terephthalate). This form may be produced from molten low molecular weight poly(trimethylene terephthalate) material by means of rapid heat transfer from the material. The poly(trimethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.

Production of poly(trimethylene terephthalate)

Disclosed herein is a novel crystalline form of low molecular weight poly(ethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(ethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(ethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight. A higher molecular weight polymer product having a unique physical form can be produced by solid-state polymerization of the low molecular weight poly(ethylene terephthalate).

Production of poly (ethylene terephthalate)

This invention is directed to an improved process for producing a polyester oligomer. The process employs a pipeline reactor, having at least two stages, in which the degree of polymerization of an oligomeric feed material is raised from about 2-10 to about 2-40 and the ratio of carboxyl to hydroxyl end groups in the product is reduced. In a first stage of the process, a monomeric diol or polyol, such as ethylene glycol, is added to a melt of the oligomeric feed material. In a second stage of the process, the molecular weight of the oligomer is increased by removal of volatile reaction by-products, including water and polyol. The oligomer produced by the present invention may be used in making higher molecular weight polyesters.

Process for polymerization of polyester oligomers

Disclosed herein is a novel crystalline form of low molecular weight poly(trimethylene terephthalate). This crystalline form may be produced from molten or glassy low molecular weight poly(trimethylene terephthalate) material by means of rapid heat transfer to or from the material. The poly(trimethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.

This invention relates to a process and apparatus for forming a polyester polymer into particles. More particularly, this invention relates to a process and apparatus for forming crystalline, uniform pellets from an amorphous polyester melt. The polyester pellets have utility, for example, as feedstock for a process for producing higher molecular weight polyesters.

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Kennett Square, PA, United States of America

Kenneth Wayne Leffew