PROCESSES FOR MAKING SHEET STRUCTURES HAVING IMPROVED COMPRESSION PERFORMANCE

摘要

This invention relates to a process for preparing a sheet structure comprising the steps of: a) combining a plurality of plies comprising thermostable floc and at least 10 weight percent aramid fibrids, and the plies further having a void content between 25 and 95 volume percent and a moisture content of 1.5 to 7 weight percent; b) providing the combined plurality of plies to a heated press for thermal laminating the plies together, the heated press having a temperature of from 250 to 400 degrees C; c) thermal laminating the plurality of plies in the heated press by compressing the plies at a pressure of at least 1.3 MPa while heating the plies at a temperature of from 250 to 400 degrees C to form a sheet structure; and d) maintaining a constant pressure of at least 1.3 MPa on the sheet structure while cooling the structure to a temperature below 100 degrees C.