Microencapsulation of materials using cenospheres

• US 10,458,117 B2
• Filed: 07/29/2016
• Issued: 10/29/2019
• Est. Priority Date: 07/30/2015
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Alabama (University of Alabama System)
• Original Assignee: Board of Trustees of The University of Alabama (University of Alabama System)
• Inventors: Wang, Jialai
• Primary Examiner(s): Ferre, Alexandre F
• Application Number:
  US15/223,292
• Publication Number:
  US 20170030077A1
• Time in Patent Office: 1,187 Days
• Field of Search: None
• CPC Class Codes: B01J 13/02 Making microcapsules or microballoons for medical preparations A61K9/50
• CPC Class Codes: B05D 1/02 performed by spraying
• CPC Class Codes: C04B 18/082 Cenospheres
• CPC Class Codes: C04B 20/1003 Non-compositional aspects of the coating or impregnation
• CPC Class Codes: C04B 20/1029 Macromolecular compounds
• CPC Class Codes: C04B 20/1033 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C04B 20/1066 Oxides, Hydroxides
• CPC Class Codes: C04B 20/1077 Cements, e.g. waterglass
• CPC Class Codes: C04B 20/12 Multiple coating or impregnating
• CPC Class Codes: C04B 20/123 Multiple coatings, for one of the coatings of which at least one alternative is described
• CPC Class Codes: C04B 2103/0071 Phase-change materials, e.g. latent heat storage materials used in concrete compositions
• CPC Class Codes: C04B 2103/32 Superplasticisers
• CPC Class Codes: C04B 2103/44 Thickening, gelling or viscosity increasing agents
• CPC Class Codes: C04B 2103/61 Corrosion inhibitors
• CPC Class Codes: C04B 2103/63 Flame-proofing agents
• CPC Class Codes: C04B 2103/67 Biocides
• CPC Class Codes: C04B 22/002 Water
• CPC Class Codes: C04B 24/08 Fats; Fatty oils; Ester type waxes; Higher fatty acids, i.e. having at least seven carbon atoms in an unbroken chain bound to a carboxyl group; Oxidised oils or fats
• CPC Class Codes: C04B 28/04 Portland cements
• CPC Class Codes: C04B 40/0641 Mechanical separation of ingredients, e.g. accelerator in breakable microcapsules
• CPC Class Codes: C09K 5/063 : Materials absorbing or liberating heat during crystallisation; Heat storage materials
• CPC Class Codes: E04C 1/40 : 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 Class Codes: E04C 2/049 : completely or partially of insulating material, e.g. cellular concrete or foamed plaster
• CPC Class Codes: E04C 2/26 : composed of materials covered by two or more of groups E04C2/04, E04C2/08, E04C2/10 or of materials covered by one of these groups with a material not specified in one of the groups of cement and mineral fibres E04C2/04
• CPC Class Codes: Y02W 30/91 : Use of waste materials as fillers for mortars or concrete

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.

Claims

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, wherein the phase change material is 20% or more by weight of the composition, and wherein the phase change material is paraffin wax.

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

3. The composition of claim 1, wherein the cenosphere has an average diameter of from about 1 μ

m to about 2,000 μ

m.

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 core material further comprises water.

6. A self-curing cement, comprising:

Portland cement and the composition of claim 5.

7. The composition of claim 1, wherein the phase change material has a melting temperature of from −

100°

C. to about 400°

C.

8. The composition of claim 1, wherein the phase change material has a melting enthalpy of from about 150 MJ/m³to about 300 MJ/m³.

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

10. 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.

11. A method of encapsulating a core material inside a perforated cenosphere, 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 and forming a composition comprising the core material encapsulated inside the perforated cenosphere;

wherein the core material comprises a phase change material;

wherein the phase change material is 20% or more by weight of the composition, and

wherein the phase change material is paraffin wax.

12. The method of claim 11, further comprising coating the perforated cenosphere encapsulating the core material with silica.

13. The method of claim 11, further comprising coating the perforated cenosphere encapsulating the core material with titania or alumina.

14. The method of claim 11, further comprising coating the perforated cenosphere encapsulating the core material with a polymer.

15. The method of claim 12, where the coating is by a sol gel process.

16. The method of claim 12, where the coating is by spray drying.

17. The method of claim 11, wherein the acid solution comprises ammonium fluoride and hydrochloric acid.