Microencapsulation of materials using cenospheres

Patent metadata

Field	Value
Publication number	US-2020024848-A1
Application number	US-201916573457-A
Country	US
Kind code	A1
Filing date	Sep 17, 2019
Priority date	Jul 30, 2015
Publication date	Jan 23, 2020
Grant date	—

Abstract

Disclosed are methods for incorporating core materials such as phase change materials or admixtures into building materials like concrete. The methods use cenospheres, which are then etched and loaded with the core material. The composition can also be coated with a thin film. Compositions containing cenospheres loaded with the various core materials are disclosed, as are building materials containing such compositions.

First claim

1 . A composition, comprising: a perforated cenosphere and a core material, wherein the core material is encapsulated inside the perforated cenosphere, wherein the core material comprises a phase change material, and wherein the phase change material comprises a salt-water solution, a sugar alcohol, a paraffin, a fatty acid, a salt hydrate, a nitrate, a hydroxide, a hygroscopic material, or combinations thereof.

2 . The composition of claim 1 , wherein the perforated cenosphere is coated with silica, titania, alumina, or a polymer.

3 . The composition of claim 1 , wherein the perforated cenosphere has an average diameter of from about 1 μm to about 2,000 μm.

4 . The composition of claim 1 , wherein the core material is from about 20% to about 90% by weight of the composition.

5 . The composition of claim 1 , wherein the phase change material comprises a fatty acid, a salt hydrate, or combinations thereof.

6 . The composition of claim 1 , wherein the phase change material is paraffin wax.

7 . The composition of claim 1 , wherein the core material further comprises water.

8 . The composition of claim 1 , wherein the phase change material has a melting temperature of from −100° C. to about 400° C.

9 . The composition of claim 1 , wherein the phase change material has a melting enthalpy of from about 150 MJ/m 3 to about 300 MJ/m 3 .

10 . The composition of claim 1 , wherein the core material further comprises a concrete admixture.

11 . The composition of claim 1 , wherein core material further comprises an antimicrobial agent, a fire retardant, a corrosion inhibitor, a viscosity modifier, superplasticizer, or air.

12 . A building material, comprising: the composition of claim 1 and a material selected from the group consisting of tile, stone, brick, mortar, cement, concrete, engineered hardwood, gypsum, plaster, stucco, tar, asphalt, insulation, porcelain, linoleum, and PVC.

13 . (canceled)

14 . A self-curing cement, comprising: Portland cement and the composition of claim 7 .

15 . A method of encapsulating a core material inside a cenosphere, the method comprising:
contacting a cenosphere with an acid solution, thereby providing the perforated cenosphere; and contacting the perforated cenosphere with the core material, thereby encapsulating the core material in the perforated cenosphere wherein the core material comprises a phase change material, and wherein the phase change material comprises a salt-water solution, a sugar alcohol, a paraffin, a fatty acid, a salt hydrate, a nitrate, a hydroxide, a hygroscopic material, or combinations thereof.

16 . The method of claim 15 , further comprising coating the perforated cenosphere encapsulating the core material with silica, titania, alumina, or a polymer.

17 . (canceled)

18 . (canceled)

19 . The method of claim 16 , where the coating is by a sol gel process.

20 . The method of claim 16 , where the coating is by spray drying.

21 . The method of claim 15 , wherein the acid solution comprises ammonium fluoride and hydrochloric acid.

Assignees

• Univ Alabama

Inventors

• Wang Jialai

Classifications

• E04C1/40

  built-up from parts of different materials, e.g. composed of layers of different materials or stones with filling material or with insulating inserts · CPC title

• C04B2103/0071

  Phase-change materials, e.g. latent heat storage materials used in concrete compositions · CPC title

• B05D1/02

  performed by spraying · CPC title

• C04B20/12

  Multiple coating or impregnating · CPC title

• C04B20/1066

  Oxides, Hydroxides · CPC title