Reinforced plastic

A prepreg comprising a unidirectional fiber reinforcement embedded in a continuous matrix of thermoplastic resin, wherein said resin comprises a high molecular weight poly(arylene sulfide ketone) resin as characterized by having an inherent viscosity greater than 0.55 dl/g, a glass transition temperature, Tg, in the range of from 125.degree. to 165.degree. C., and a melting temperature, Tm, in the range of from 300.degree. to 500.degree. C., a measurable melt flow rate of less than about 1000 g/10 minutes, and a calcium content from about 50 to about 10,000 ppm by weight based on elemental calcium, and wherein said unidirectional fiber reinforcement is selected from the group consisting of a strand, a roving and a yarn.

A prepreg comprising a unidirectional fiber reinforcement embedded in a continuous matrix of a poly(arylene sulfide ketone) resin, which has been treated to improve melt stability, said resin having an inherent viscosity greater than 0.55 dl/g, a glass transition temperature, Tg, in the range of from 125.degree. to 165.degree. C., and a melting temperature, Tm, in the range of from 300.degree. to 500.degree. C., a measurable melt flow rate of less than about 1000 g/10 minutes, and a calcium content from about 50 to about 10,000 ppm by weight based on elemental calcium, wherein, said prepreg is prepared by slurry impregnation of the unidirectional fiber reinforcement with particles of the resin and the resin, before preparation of the slurry of the resin for impregnation of the unidirectional fiber reinforcement, is treated with an aqueous solution containing from about 1 weight percent to about 10 weight percent of a source of an alkaline earth metal for a time and temperature to effect treatment of the resin to improve melt stability.

A prepreg comprising a unidirectional fiber reinforcement embedded in a continuous matrix of a poly(arylene sulfide ketone) resin containing repeating units of the structural formula ##STR2## and having an inherent viscosity greater than 0.55 dl/g, a glass transition temperature, Tg, in the range of from 125.degree. to 165.degree. C., and a melting temperature, Tm, in the range of from 300.degree. to 500.degree. C., a measurable melt flow rate of less than about 1000 g/10 minutes, and a calcium content from about 50 to about 10,000 ppm by weight based on elemental calcium, said prepreg having been prepared by a process comprising (a) treating an untreated resin with an aqueous solution containing from about 1 weight percent to about 10 weight percent of a source of an alkaline earth metal for a time and at a temperature to form a treated resin of improved melt-stability, (b) preparing a slurry from the treated resin, and (c) impregnating the unidirectional fiber reinforcement with the treated resin in the slurry.

A prepreg comprising a unidirectional fiber reinforcement embedded in a continuous matrix of thermoplastic resin, wherein said resin comprises a high molecular weight poly(arylene sulfide ketone) resin having an inherent viscosity greater than 0.55 dl/g, a glass transition temperature, Tg, in the range of from 125.degree. to 165.degree. C., a melting temperature, Tm, in the range of from 300.degree. to 500.degree. C., a calcium concentration from about 50 to about 10,000 ppm by weight based on elemental calcium, and a measurable melt flow rate of less than about 1000 g/10 minutes measured by ASTM D 1238 at 371.degree. C. with a 5 Kg weight, wherein the continuous matrix of thermoplastic resin is removable from the unidirectional fiber reinforcement by digestion in nitric acid and wherein the prepreg comprises from about 25 weight percent to about 80 weight percent unidirectional fiber reinforcement, based on the total weight of the resin and reinforcement being taken as 100%.