Dual-mediated polymerizable composite for additive manufacturing

Abstract

A formulation for a photopolymer composite material for a 3D printing system includes an acrylate monomer or an acrylate oligomer, an inorganic hydrate, a reinforcing filler, a co-initiator, a thermal initiator, and an ultraviolet (UV) initiator. In the formulation the acrylate monomer or the acrylate oligomer may be between about 10.0-30.0 w % of the formulation. The thermal initiator may be between about 0.001-0.05 w %, the co-initiator may be between about 0.001-0.05 w %, and the UV initiator may be between about 0.001-0.2 w % of the formulation. A method of generating a formulation of a photopolymer composite material for use in a 3D printing system includes using an acrylate monomer or an acrylate oligomer, an inorganic hydrate, a reinforcing filler, a co-initiator, a thermal initiator, and an ultraviolet (UV) initiator.

1 . A method of generating a large-scale three-dimensional (3D) printed structure, the method comprising:
 generating a resin premix by blending a formulation of an acrylate monomer, acrylate oligomer, an ultraviolet (UV) initiator, an inorganic hydrate, a co-initiator, and a reinforcing filler through operation of a mixing system for a first amount of time, the mixing system comprising a blender;   combining a thermal initiator with the resin premix; and   generating a photopolymer composite resin by blending the thermal initiator and the resin premix through operation of the blender for a second amount of time;   extruding the photopolymer composite resin via a 3D printing system; and   applying a UV LED light source to the extruded photopolymer composite to initiate the hardening of the photopolymer composite by activating the thermal reaction.   
     
     
         2 . The method of  claim 1 , wherein the an acrylate monomer and an acrylate oligomer are in the range between about 10.0-30.0 w % of the formulation, the UV initiator is in the range between about 0.001-0.2 w % of the formulation, the co-initiator in the range between about 0.001-0.05 w of the formulation, the inorganic hydrate, comprising a borax decahydrate, is in the range between about 22.0-30.0 w % of the formulation, and the reinforcing filler, is in the range between about 50.0-80.0 w % of the formulation, and the thermal initiator is in the range between about 0.001-0.05 w % of the formulation. 
     
     
         3 . The method of  claim 1 , further comprising:
 after generating the photopolymer composite resin, loading the photopolymer composite resin from the blender into a mixing tank of the 3D printing system.   
     
     
         4 . The method of  claim 1 , further comprising:
 combining with the resin premix a flame-retardant additive in the range between about 35.0 to 75.0 w % of the formulation, the flame-retardant additive including at least sodium tetraborate and boric acid.   
     
     
         5 . The method of  claim 4 , wherein the hardened photopolymer composite is characterized as having a fire protection rating (FSR)<25. 
     
     
         6 . The method of  claim 1 , wherein the resin premix is characterized by having a first uncured state in the form of a thixotropic liquid with a UV light cure depth in the range of 5 mm to 15 mm. 
     
     
         7 . The method of  claim 1 , wherein the photopolymer composite resin is characterized as having a second cured state in the form of a hardened, non-liquid material where the uncured composite resin has been exposed to a UV light. 
     
     
         8 . The method of  claim 1 , further comprising:
 combining the resin premix with a dye or pigment in the range between about 0.001-0.05 w of the formulation.   
     
     
         9 . The method of  claim 1 , wherein the thermal initiator is at least partially dissolved in acrylate monomer to form a liquid thermal initiator, and the resin premix is combined with the liquid thermal initiator, and the second amount of time is in the range between about 5 seconds to 60 seconds to achieve the proper mix of photopolymer composite resin dependent on the printing speed and layer size. 
     
     
         10 . The method of  claim 1 , wherein the blender comprising a ribbon blender having a discharge valve; and the mixing system comprises a first pump in fluid communication with the ribbon blender, the pump configured to pump the acrylate oligomer into the ribbon blender. 
     
     
         11 . The method of  claim 1 , further comprising:
 forming a structural wall with the hardened photopolymer composite, the structural wall having a plurality of hollowed out portions.   
     
     
         12 . The method of  claim 1 , wherein the hardened photopolymer composite is characterized as having an ultimate compressive strength of ranging from 66+/−3 Megapascal (MPa). 
     
     
         13 . The method of  claim 1 , wherein the hardened photopolymer composite is characterized as having a compressive modulus of elasticity of 5600+/−200 Megapascal (MPa). 
     
     
         14 . The method of  claim 1 , wherein the hardened photopolymer composite is characterized as having an ultimate tensile strength of 7.6+/−0.9 Megapascal (MPa). 
     
     
         15 . The method of  claim 1 , wherein the hardened photopolymer composite is characterized as having a tensile modulus of elasticity of 4400+/−400 Megapascal (MPa). 
     
     
         16 . The method of  claim 1 , wherein the UV LED light source has a maximum light intensity of up to 43 W/cm2 with a diameter of spot size of about 20 mm 
     
     
         17 . A method of generating a large-scale 3D printed structure, the method comprising:
 generating a resin premix by blending a formulation of an acrylate monomer, acrylate oligomer, an ultraviolet (UV) initiator, an inorganic hydrate, a co-initiator, and a reinforcing filler through operation of a mixing system for a first amount of time ranging between about 5 and 20 minutes, the mixing system comprising a blender;   combining a thermal initiator with the resin premix; and   generating a photopolymer composite resin by blending the thermal initiator and the resin premix through operation of the blender for a second amount of time ranging from about 10 and 14 hours before the photopolymer composite resin can be considered ready for use;   extruding the photopolymer composite resin via a 3D printing system, the 3D printing system comprising a nozzle and a UV LED light source; and   applying the UV LED light source at a first light intensity to the extruded photopolymer composite to harden the photopolymer composite.   
     
     
         18 . The method of  claim 17 , further comprising:
 applying the UV LED light source at a second light intensity to the extruded photopolymer composite to further harden the photopolymer composite.   
     
     
         19 . The method of  claim 17 , wherein the an acrylate monomer and an acrylate oligomer are in the range between about 10.0-30.0 w % of the formulation, the UV initiator is in the range between about 0.001-0.2 w % of the formulation, the co-initiator in the range between about 0.001-0.05 w % of the formulation, the inorganic hydrate, comprising a borax decahydrate, is in the range between about 22.0-30.0 w % of the formulation, and the reinforcing filler, is in the range between about 50.0-80.0 w % of the formulation, and the thermal initiator is in the range between about 0.001-0.05 w % of the formulation. 
     
     
         20 . The method of  claim 17 , wherein the thermal initiator is a powder and blending the thermal initiator in the range between about 30 seconds to 5 minutes to mix the thermal initiator into the resin premix based on the sprinting speed and volume. 
     
     
         21 . The method of  claim 17 , further comprising:
 loading the photopolymer composite resin into a container for storage; and   mixing the photopolymer composite resin at a time interval ranging from 3 hours to 7 days to maintain the ready to use state of the photopolymer composite resin.