Dual cure additive manufacturing of rigid intermediates that generate semi-rigid, flexible, or elastic final products

A method of forming a three-dimensional object comprised of polyurethane, polyurea, or copolymer thereof, said method comprising:

• (a) providing a carrier and a fill level, said carrier and said fill level having a build region therebetween;
• (b) filling said build region with a polymerizable liquid, said polymerizable liquid comprising at least one of:
• (i) a blocked or reactive blocked prepolymer, (ii) a blocked or reactive blocked diisocyanate or branched isocyanate, or (iii) a blocked or reactive blocked diisocyanate or branched isocyanate chain extender;
• (c) irradiating said build region with light to form a solid blocked polymer scaffold and advancing said carrier away from said fill level to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, said three-dimensional object, with said three-dimensional intermediate containing said (i) blocked or reactive blocked prepolymer, (ii) blocked or reactive blocked diisocyanate or branched isocyanate, or (iii) blocked or reactive blocked diisocyanate or branched isocyanate chain extender;
• (d) optionally washing said three-dimensional intermediate;
• and then
• (e) heating and/or microwave irradiating said three-dimensional intermediate sufficiently to form from said three-dimensional intermediate said three-dimensional object comprised of polyurethane, polyurea, or copolymer thereof;
• optionally with said heating and/or microwave irradiating step (e) increasing the elasticity and/or decreasing the rigidity of said three-dimensional intermediate in forming said three-dimensional object.

A method of forming a three-dimensional object, comprising:

• (a) providing a carrier and a fill level, said carrier and said fill level having a build region therebetween;
• (b) filling said build region with a polymerizable liquid, said polymerizable liquid comprising a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from said first component;
• (c) irradiating said build region with light to form a solid polymer scaffold from said first component and also advancing said carrier away from said fill level to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, said three-dimensional object and containing said second solidifiable component carried in said scaffold in unsolidified and/or uncured form;
• (d) optionally washing said three-dimensional intermediate;
• and
• (e) subsequent to said irradiating step, solidifying and/or curing said second solidifiable component in said three-dimensional intermediate to form said three-dimensional object;
• with said solidifying and/or curing step (e) increasing the elasticity and/or decreasing the rigidity of said three-dimensional intermediate in forming said three-dimensional object,
• wherein said three-dimensional object comprises a polymer blend, interpenetrating polymer network, semi-interpenetrating polymer network, or sequential interpenetrating polymer network formed from said first component and said second solidifiable component,
• wherein said second solidifiable component comprises precursors to a polyurethane, polyurea, or copolymer thereof, a silicone resin, an epoxy resin, a cyanate ester resin, or a natural rubber, and
• wherein said solidifying and/or curing step (e) is carried out by heating.