Abstract: Disclosed is a process of forming a prepreg material having substantially no voids. According to the process of the invention, the reinforcing material is heated to a temperature above the temperature of the impregnating resin. The prepreg formed has substantially no voids and does not require lengthy consolidation when formed into useful articles.

Abstract: An improved multifilamentary fibrous material is formed having particles of a matrix-forming thermoplastic polymer substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The polymer particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the polymer particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the polymer particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product.

Abstract: Compositions are disclosed which are suitable for the preparation of thermoplastic syntactic foam intermediate and final products. These compositions comprise a slurry or putty containing thermoplastic particles, microballoons, and a non-solvent, optionally in the presence of suitable thickeners, binders, and surfactants. In a preferred embodiment, the composition contains particles of an engineering thermoplastic having a mean particle size less then about 100 .mu.m, microballoons, water as the non-solvent, and a thickener/binder which is a lightly crosslinked polyacrylic acid.

Abstract: An improved multifilamentary fibrous material is formed having solid particles of a matrix-forming thermosetting resin substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The thermosetting resin particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the thermosetting resin particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the resin particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product.

Abstract: An improved multifilamentary fibrous material is formed having solid particles of a matrix-forming thermosetting resin substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The thermosetting resin particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the thermosetting resin particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the resin particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product.

Abstract: An improved multifilamentary fibrous material is formed having particles of a matrix-forming thermoplastic polymer substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The polymer particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the polymer particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the polymer particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product.