Methods of using thermoplastic polyurethanes in selective laser sintering and systems and articles thereof

A method of fabricating a three-dimensional object, comprising the step of:

• (I)
• operating a system for producing a three-dimensional object from a powder;
• wherein said system comprises a solid freeform fabrication apparatus that selectively fuses layers of powder;
• so as to form the three-dimensional object;
• wherein said powder comprises a thermoplastic polyurethane derived from (a) a polyisocyanate component, (b) a polyol component, and (c) an optional chain extender component wherein the thermoplastic polyurethane has a weight average molecular weight measured by GPC of less than 150,000;
• wherein said powder has an average particle diameter of less than 150 microns;
• wherein the resulting thermoplastic polyurethane has a melting enthalpy of at least 10 J/g;
• wherein the resulting thermoplastic polyurethane has a Tc of at least 90° C.;
• wherein the resulting thermoplastic polyurethane has a Tm measured by DSC of greater than 170° C.;
• and
• wherein the resulting thermoplastic polyurethane has a Δ(Tm:Tc) of between 58° C. and 71° C.