Production of semicrystalline parts from pseudo-amorphous polymers

A method of manufacturing a semi-crystalline article from at least one pseudo-amorphous polymer using a thermo-forming process, said method comprising:

• as a softening step, heating at least one pseudo-amorphous polymer having less than about seven % crystallinity and in sheet form to a temperature above the glass transition temperature of the pseudo-amorphous polymer to soften the pseudo-amorphous polymer;
• as a crystallization step, heating the at least one pseudo-amorphous polymer to a temperature above the glass transition temperature of the pseudo-amorphous polymer and below the melting temperature of the pseudo-amorphous polymer for a time sufficient to allow the crystallinity of pseudo-amorphous polymer to increase on a mold;
• placing the pseudo-amorphous polymer on the mold during either the softening step or the crystallization step before the increase in crystallization takes place;
• and
• forming an semi-crystalline molded article wherein said crystallinity increases by at least 5% (absolute) crystallinity over the pseudo-amorphous polymer,
• wherein the pseudo-amorphous polymer comprises (i) poly aryl ether ketone (PAEK) selected from the group consisting of polyetherketoneketone (PEKK), polyetherketone (PEK), polyetherketoneetherketoneketone (PEKEKK), and mixtures thereof and (ii) another polymer selected from the group consisting of fluorinated polymers, polyimides, polysulfones, and polysulfides.