Foamed liquid crystal polymer film/sheet having improved flexibility and cell uniformity

DETAILED DESCRIPTION The present invention is a flexible foamed liquid crystal polymer film or sheet having uniformly small cells or bubbles.
The foam cells have mean diameters in the approximate range of 10 to 250 microns.
The cell size distribution is relatively narrow.
To produce the film or sheet of this invention, it is important to control the processing conditions carefully during the foaming operation.
The process comprises the extrusion of LCP and blowing agent or gas composition under sufficient pressure at a temperature near or below its melting point.
This process maximizes polymer melt viscosity in the die and localizes bubble expansion at the point of exit from the die.
It is an object of the present invention to provide a foamed liquid crystal polymer having relatively small, uniform foam cell sizes.
It is another object of this invention to provide a flexible foamed LCP film.
It is a further object of the present invention to provide a process for forming foamed LCP having small and relatively uniform cells.
Further objects of the present invention will be apparent to those skilled in the art from the following disclosure and the appended claims.