Self-inflating microcapsules

Patent metadata

Field	Value
Publication number	US-2018141019-A1
Application number	US-201815877213-A
Country	US
Kind code	A1
Filing date	Jan 22, 2018
Priority date	Jul 23, 2015
Publication date	May 24, 2018
Grant date	—

Abstract

A method comprises providing an aqueous solution having an alkaline pH and providing an oil including at least one silsesquioxane compound. The oil is added to the aqueous solution. The oil forms a plurality of silsesquioxane oil droplets suspended in the aqueous solution such that an internal osmotic pressure is generated inside the oil droplets via a chemical reaction. The aqueous solution is allowed to osmotically diffuse into the plurality of oil droplets for a predetermined time. The silsesquioxane oil droplets are polymerized by cross-linking the at least one silsesquioxane compound included in the silsesquioxane oil droplets to form a plurality of solidified microcapsules containing the aqueous solution therewithin.

First claim

What is claimed is:

1 . A method, comprising:
providing an aqueous solution having an alkaline pH; providing an oil including at least one silsesquioxane compound; adding the oil to the aqueous solution, the oil forming a plurality of silsesquioxane oil droplets suspended in the aqueous solution, the adding generating an internal osmotic pressure inside the oil droplets by means of a chemical reaction; allowing the aqueous solution to osmotically diffuse into the plurality of silsesquioxane oil droplets for a predetermined time; and polymerizing the silsesquioxane oil droplets by cross-linking the at least one silsesquioxane compound included in the silsesquioxane oil droplets to form a plurality of solidified microcapsules containing the aqueous solution therewithin.

2 . The method of claim 1 , wherein the silsesquioxane compound includes at least one of a hydrolysable silane monomer and a low molecular weight silsesquioxane oligomer.

3 . The method of claim 2 , wherein the at least one silsesquioxane compound includes a compound of formula I:
RSiO 3/2   (I)

where:
Si is silicon;
O is oxygen; and
R is hydrogen, alkyl, alkene, aryl or arylene.

4 . The method of claim 1 , wherein allowing the aqueous solution to osmotically diffuse into the oil droplets inflates the oil droplets.

5 . The method of claim 1 , wherein the chemical reaction includes a base catalyzed hydrolysis.

6 . The method of claim 1 , further comprising:
dissolving a compound in the aqueous solution, wherein the diffusing urges the compound to also diffuse into the oil droplets such that the plurality of microcapsules contain the compound therewithin with the aqueous solution.

7 . The method of claim 6 , wherein the compound includes at least one of a fluorescent dye, a pharmaceutical, a nutraceutical, and a polymerizable moiety.

8 . The method of claim 1 , wherein the microcapsules have a diameter in the range of 100 nm to 10 microns.

9 . The method of claim 1 , further comprising:
dissolving a compound into the oil, wherein a combination of the diffusing and polymerization separates the compound from the oil such that the microcapsules contain the compound with the aqueous solution contained therewithin.

10 . The method of claim 1 , further comprising:
suspending nanoparticles in the oil, wherein the polymerization traps the nanoparticles into a shell of the plurality of microcapsules.

11 . A method, comprising:
providing an aqueous solution having an alkaline pH; adding an oil to the aqueous solution, the oil including at least one silsesquioxane compound; allowing the oil to undergo a hydrolysis-and-condensation reaction, a plurality of silsesquioxane oil droplets forming in the oil via a homogenous nucleation reaction; adding an osmotic pressure compound to the aqueous solution; allowing the aqueous solution to diffuse into the plurality of silsesquioxane oil droplets for a predetermined time; and polymerizing the oil droplets by cross-linking the at least one silsesquioxane compound included in the silsesquioxane oil droplets to form a plurality of microcapsules, wherein the each of the plurality of microcapsules are inflated and contain aqueous solution.

12 . The method of claim 11 , wherein the silsesquioxane compound includes at least one of a hydrolysable silane monomer and a low molecular weight silsesquioxane oligomer.

13 . The method of claim 11 , further comprising adding a surfactant to the colloidal suspension.

14 . The method of claim 11 , wherein the osmotic pressure compound consists of a base.

15 . The method of claim 14 , wherein the base is selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH), and tetramethylammonium hydroxide (TMAH).

16 . The method of claim 11 , further comprising dissolving a compound in the oil prior to addition of the oil to the aqueous solution.

17 . The method of claim 11 , further comprising dissolving a compound in the aqueous solution prior to addition of the oil.

18 . The method of claim 11 , wherein the dissolved compound includes at least one of quantum nanodots, photocatalytic nanoparticles, magnetic nanoparticles, porous silica nanoparticles and poly(n-i sopropylacrylamide) nanoparticles.

19 . A method, comprising:
providing an aqueous solution having an alkaline pH; adding an oil to the aqueous solution, the oil including at least one silsesquioxane compound, the oil forming a plurality of silsesquioxane oil droplets suspended in the aqueous solution, the adding generating an internal osmotic pressure inside the oil droplets by means of a chemical reaction; allowing the aqueous solution to osmotically diffuse into the plurality of silsesquioxane oil droplets for a predetermined time; polymerizing the silsesquioxane oil droplets by cross-linking the at least one silsesquioxane compound included in the silsesquioxane oil droplets to form a plurality of solidified microcapsules containing the aqueous solution therewithin; drying the plurality of solidified microcapsules; exposing the plurality of solidified microcapsules to a gas to infuse the gas into the plurality of solidified microcapsules; and exposing the plurality of solidified microcapsules to a hydrophobic volatile silane, wherein the silane seals the plurality of solidified microcapsules to trap the gas therewithin.

20 . The method of claim 19 , further comprising:
suspending the plurality of solidified microcapsules in an aqueous solution including a surfactant.

Assignees

• Univ New York

Inventors

• Sacanna Stefano
• Hueckel Theodore

Classifications

• B01J13/18 Primary

  In situ polymerisation with all reactants being present in the same phase · CPC title

• A61K8/11

  Encapsulated compositions · CPC title

• B01J13/20

  After-treatment of capsule walls, e.g. hardening · CPC title

• A61K2800/412

  Microsized, i.e. having sizes between 0.1 and 100 microns · CPC title

• B01J13/14

  Polymerisation; cross-linking · CPC title