Process for preparing fiber reinforced molded articles

• Main Authors: ANGELL, RICHARD GORDON, DOMEIER, LINDA ANN
• Format: Patent
• Language: English; French; German
• Published: 05.01.1983
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

Described herein is an improved process for rapidly fabricating fiber reinforced thermoset resin articles comprising: (a) providing in a heatable matched metal die mold a bonded web of one or more fibers with a melting point or a glass transition temperature above about 130 DEG C, (b) providing in an accumulator zone a liquid body of a thermosettable organic material having a viscosity determined at 120 DEG C, in the absence of curing agent, of less than about 50 centipoises, which is curable upon heating to a thermoset resin composition, the viscosity of said liquid body being maintained essentially constant in the accumulator zone by keeping its temperature below that at which curing of said materials is substantial (c) closing said mold containing said web, (d) injecting at least a portion of said thermosettable organic material under pressure from said accumulator zone into the mold to thereby fill the cavity in said mold, (e) initiating the curing of said materials by subjecting the materials to a temperature by heating the mold, which is above the temperature at which the curing of said materials is initiated, and (f) opening said molding and removing the cured thermoset article therefrom, wherein the improvement comprises improving the release of the cured article from the mold by increasing the cross-link density of the cured thermosettable organic material in the molded article. Also described herein are curable molding compositions used for the rapid fabrication of fiber-reinforced thermoset resin articles having improved mold release characteristics.