Encapsulant-containing polymer capsules and fibers and composites including same
View Patent ↗Systems and methods for preparing encapsulant-containing polymer capsules and fibers, as well as the encapsulant-containing polymer capsules and fibers and composites including the same are described. In one example, forming a plurality of encapsulant-containing polymer capsules includes preparing a mixture comprising a polymer, a solvent, an encapsulant, and a polymer that is soluble in the solvent, and removing some of the solvent from the mixture to yield the plurality of polymer capsules. Each polymer capsule include a shell formed of the polymer and contains the encapsulant. In another example, forming a plurality of polymer fibers containing an encapsulant includes providing the mixture to an electrospin apparatus and electrospinning the mixture to yield the plurality polymer fibers, where each polymer fiber defines a hollow core that contains the encapsulant.
1 . A method of forming a plurality of polymer capsules containing an encapsulant, the method comprising:
preparing a mixture comprising a polymer, a solvent, and an encapsulant, wherein the polymer is soluble in the solvent and the encapsulant comprises an ionic liquid;
providing the mixture to a gas-assisted electrospray apparatus; and
ejecting the mixture from the gas-assisted electrospray apparatus to form the plurality of polymer capsules, wherein each polymer capsule comprises a shell formed of the polymer and contains the encapsulant, and the encapsulant is in the form of a liquid.
2 . The method of claim 1 , wherein the solvent comprises water, dimethylformamide, tetrahydrofuran, chloroform, or any mixture thereof.
3 . The method of claim 1 , wherein the encapsulant is an ionic liquid.
4 . The method of claim 1 , wherein the ionic liquid comprises a phosphonium, ammonium, or imidazolium based ionic liquid.
5 . The method of claim 4 , wherein the ionic liquid comprises 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or bis(2,4,4-trimethylpentyl)phosphinate.
6 . The method of claim 1 , wherein the polymer comprises polysulfone, polyacrylonitrile, polyvinyl chloride, polyvinylidene fluoride, or poly(methyl methacrylate).
7 . The method of claim 1 , wherein each of the polymer capsules has an outer diameter in a range of about 500 nm to about 20 μm.
8 . The method of claim 1 , wherein a gas pressure of the gas-assisted electrospray apparatus is in a range of 5 psi to 40 psi.
9 . The method of claim 1 , wherein a gas of the gas-assisted electrospray apparatus comprises argon, nitrogen, oxygen, carbon dioxide, or a combination thereof.