Porous random fiber composites and a method for preparing same

Abstract

A process for preparing a porous random fiber polymeric composite sheet through the addition of a cellulose ether which is selectively soluble or insoluble to a random fiber composite slurry under conditions such that the cellulose ether is insoluble, forming the slurry into a sheet, fusing the organic polymer component of the sheet and heating the sheet to solubilize the cellulose ether whereby voids are formed in the sheet. Before the sheet is treated to remove the cellulose ether, it may be combined with other sheets and densified under heat and pressure. Before removing the cellulose ether, the densified sheet may be heated under reduced pressure to expand or loft the sheet in a direciton normal to the plane of the sheet. A random fiber polymeric composite sheet, a densified sheet and a lofted sheet, each comprising a binder, fusable organic polymer, reinforcing material and a cellulose ether are also provided. The same sheets after removal of the cellulose ether are further provided.

Dependencies are inferred from the claim text.