Abstract: In one instance a semicrystalline polyketone powder useful for additive manufacturing is comprised of a bimodal melt peak determined by an initial differential scanning calorimetry (DSC) scan at 20° C./min and a D90 particle size of at most 300 micrometers and average particle size of 1 micrometer to 150 micrometers equivalent spherical diameter. In another instance, A composition is comprised of a semicrystalline polyketone powder having a melt peak and a recrystallization peak, wherein the melt peak and recrystallization peak fail to overlap.

Abstract: An additive manufactured condensation polymer article with improved build or Z direction strength may be formed by physically mixing or depositing thereon a chain extender that extends and chemically bonds the polymer chains within and between layers upon heating and fusing during the additive manufacturing process.

Abstract: A semi-crystalline blended polymer useful for additive manufacturing is comprised of an amorphous thermoplastic polymer and a thermoplastic semi-crystalline polymer, each of the polymers being essentially miscible in the other and being blended at a weight ratio of amorphous polymer/semi-crystalline polymer of greater that 1 to about 20. The semi-crystalline blended polymer displays a DSC melt peak enthalpy of at least about 3 joules/g. The semi-crystalline polymer may be made by blending the aforementioned polymers at the weight ratio and subject to heating between the melt temperature of the semi-crystalline polymer and the glass transition temperature of the amorphous polymer. The semi-crystalline blended polymer may revert to essentially an amorphous polymer when additive manufactured by fusing layers of said polymer powders together.

Abstract: A semicrystalline poly ketone powder useful for additive manufacturing may be made by dissolving a polyketone having differential scanning calorimetry (DSC) monomodal melt peak, at a temperature above 50° C. to below the melt temperature of the polyketone, precipitating the dissolved polyketone by cooling, addition of a nonsolvent or combination thereof. The method may be used to form polyketones having a DSC melt peak with an enthalpy greater than the starting polyketone.

Abstract: Polymer powders useful for additive manufacturing may be made by contacting carbon dioxide and a crystallizable polymer having at least one carbonyl, sulfur oxide or sulfone group; permeating the carbon dioxide into the polymer for a crystallizing time sufficient to induce crystallization forming an induced crystalized polymer; removing the carbon dioxide; and forming induced crystalized polymer particles having a D90 particle size of at most 300 micrometers and average particle size of 1 micrometer to 100 micrometers equivalent spherical diameter. The carbon dioxide is desirably supercritical carbon dioxide for at least a portion of the crystallizing time. The polymer powders upon heating during additive manufacturing may result in a polymer having less crystallinity or become amorphous.

Abstract: An additive manufacturing composition useful as a support material for common build materials (e.g., polyamide or polyester) is comprised of a blend of an elastomer toughened styrenic polymer having discreet domains of polymerized conjugate diene dispersed within a styrenic matrix and a vinyl aromatic-maleic anhydride copolymer. The composition may be used as a support material in additive manufacturing methods such as extrusion methods (e.g., fused filament fabrication). The compositions may be tuned to realize the desired adherence to facilitate the desired support while also allowing for the mechanical removal without breakage of the underlying part or residual adhered support material.