CERAMIC PARTICLES IN A BICONTINUOUS PHASE AND METHOD OF PRODUCTION THEREFOR
An extrudable composition includes: an aqueous phase comprising acidic water and piezoelectric ceramic particles suspended in the water; and, an organic phase having an organic solvent, a curable polymer precursor or both an organic solvent and a curable polymer precursor. The composition is 3-D printable to form a self-supporting structure and may be infiltrated with an organic polymer material or cured so that the curable polymer precursor forms an organic polymer material thereby forming a piezoelectric composite having piezoelectric ceramic particles in a co-continuous phase.
1 . An extrudable composition comprising:
an aqueous phase comprising acidic water and piezoelectric ceramic particles suspended in the water; and,
an organic phase comprising an organic solvent, a curable polymer precursor or both an organic solvent and a curable polymer precursor.
2 . The composition of claim 1 , having a form factor selected from the group consisting of a composite filament, a composite pellet, a composite powder, and a composite paste.
3 . The composition of claim 2 , wherein the form factor is a composite paste.
4 . The composition of claim 1 , wherein the ceramic particles comprise lead zirconate titanate (PZT) particles.
5 . The composition of claim 1 , wherein the ceramic particles are present in the paste in an amount of 70 wt % or less, based on total weight of the paste.
6 . The composition of claim 1 , wherein the ceramic particles are present in the paste in an amount of 65 wt % or less, based on total weight of the paste.
7 . The composition of claim 1 , wherein the aqueous phase further comprises one or more of a sol-gel of ceramic particles, nanocarbon particles, a water-soluble polymer binder and a surfactant.
8 . The composition of claim 1 having a viscosity in a range of 5,000-100,000 cP, as measured at shear rate of 0.08 s −1 .
9 . The composition of claim 1 , wherein the organic phase comprises the organic solvent.
10 . The composition of claim 1 , wherein the organic phase comprises the curable polymer precursor.
11 . A piezoelectric composite comprising piezoelectric ceramic particles in a co-continuous phase with an organic polymeric material, the piezoelectric composite produced by curing the composition as defined claim 1 .
12 . The material of claim 11 , wherein the co-continuous phase is a bicontinuous phase.
13 . A method for producing a piezoelectric composite comprising piezoelectric ceramic particles in a co-continuous phase with an organic polymeric material, the method comprising:
a) providing the composition as defined in claim 1 wherein the organic phase comprises the organic solvent,
allowing the organic solvent to evaporate to form a porous ceramic structure and
infiltrating the porous ceramic structure with the organic polymeric material to form the piezoelectric composite; or,
b) providing the composition as defined in any one of claims 1 to 8 wherein the organic phase comprises the curable polymer precursor,
curing the curable polymer precursor to form the organic polymeric material thereby forming the piezoelectric composite.
14 . The method of claim 13 , wherein the co-continuous phase is a bicontinuous phase.
15 . The method of claim 13 , wherein the method comprises step b) and the curing is accomplished thermally or photonically in the presence or absence of an initiator.