Arkema Inc.

Arkema France

Manuel A Garcia-Leiner

Anthony DeCarmine

Christopher A Bertelo

Jack J Reilly

Scott F Defelice

Jean-Alex Laffitte

Christophe Roger

Lawrence H Judovits

James Bradley

Julie Boyer

Jean Kryven

Stephan Moyses

Scott DeFelice

Bruce Clay

Anthony Decarmine

The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved flow and improved durability of the powder particle size for applications that require powder flow at elevated temperatures. In addition to improved powder properties, the articles produced from the powders also exhibit better physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.

Heat treated polymer powders

A method of manufacturing an article comprises rotomolding at least one polymer comprising a poly(aryl ketone), such as PEKK, under conditions effective to produce a rotomolded article having an impact value of at least 35 in-lbs. A rotomolding method comprises heating the mold for a period of time after the internal air temperature of the mold reaches the highest melting point of the at least one polymer. Methods also include using a PEKK powder with a bulk density of at least about 400 g/L. Rotomolded articles of the present invention have impact values of between about 40 in-lbs to about 95 in-lbs, and in particular embodiments greater than about 95 in-lbs.

Rotomolding processes for poly(aryl ketones) and other high temperature polymers

A method of manufacturing a film or membrane includes: (a) dissolving at least one polymer comprising a poly(aryl ketone) in at least one solvent to form a dope; (b) depositing the dope on a substrate to form a coated substrate at appropriate conditions; and (c) drying the coated substrate to form the film or membrane. The dope may also include additional polymers or fillers, such as carbon nanotubes.

Films and membranes of poly(aryl ketones) and methods of casting the same from solution

Films and membranes of poly (aryl ketones) and methods of casting the same from solution

The invention relates to a translucent, white, light-diffusing thermoplastic composition containing both white pigment and refractive index-matched particles. The blend of pigment and particles provides a synergistic effect, resulting in a very high luminous transmission and good diffusion properties.

White light diffusing thermoplastic composition

The invention relates to multi-layer composites for use as a screen, having at least three layers, with an inner diffusing layer and at least one substrate layer on either side. The diffusing layer contains small particles having a narrow particle size distribution that are refractive-index mismatched with the polymer matrix. The multi-layer acrylic composition is useful as a projection screen.

Multi-layer screen composites

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Baltimore, MD, United States of America

Manuel A Garcia-Leiner