Abstract: A polymer composition especially suitable for producing fiber-reinforced structures having advantageous fracture toughness comprises a polyarylsulphone component and a thermoset resin component, each of which components is present at least partly as a phase continuous in at least one dimension. Preferred polyarylsulphones contain repeating units (PhSO.sub.2 Ph).sub.n and (Ph).sub.a linked through ether and/or thioether, where Ph is phenylene, n=1 to 2 and a=1 to 3; and such polyarylsulphones having amino end groups are provided as new compounds. The compositions can be made by spinodal decomposition of a mixture of the polyarylsulphone and a thermoset resin precursor.

Abstract: A curable moulding composition in the form of a flowable particulate solid substantially non self-adhesive at temperatures up to 60.degree. C., flowable under shear and self-adhesive at temperatures in the range 60.degree.-150.degree. C. and hardenable at temperature over 150.degree. C., said composition comprising an uncured or partly cured thermoset resin precursor and, mixed intimately therewith, a polyarylsulphone containing the repeating units (Ph SO.sub.2 Ph).sub.n and Ph.sup.1.sub.a linked through ether and/or thioether, where Ph is paraphenylene, Ph.sup.1 is phenylene, n is 1 to 2 a is 1 to 3 and groups Ph.sup.1 are (when a exceeds 1) linked through a single chemical bond or a divalent group other than SO.sub.2 or alkylene or are fused together. Preferably the polyarylsulphone contains end-groups of formula --D--Y where D is a divalent aromatic hydrocarbon group and Y is a group reactive with the thermoset precursor and has been incipiently reacted with the thermoset precursor.

Abstract: A polymer composition especially suitable for producing fibre-reinforced structures having advantageous fracture toughness comprises a polyarylsulphone component and a thermoset resin component, each of which components is present at least partly as a phase continuous in at least one dimension. Preferred polyarylsulphones contain repeating units (PhSO.sub.2 Ph).sub.n and (Ph).sub.a linked through ether and/or thioether, where Ph is phenylene, n=1 to 2 and a=1 to 3; and such polyarylsulphones having amino end groups are provided as new compounds. The compositions can be made by spinodal decomposition of a mixture of the polyarylsulphone and a thermoset resin precursor.

Abstract: A moulding composition comprising an uncured or partly, cured thermoset resin precursor and, mixed intimately therewith, a polyarylsulphone containing the repeating unit (Ph, SO.sub.2, PH).sub.n, where Ph is phenylene and n is 1 or 2, linked through ether and/or thioether.