Cementitious building material incorporating end-capped polyethylene glycol as a phase change material

• US 4,587,279 A
• Filed: 08/31/1984
• Issued: 05/06/1986
• Est. Priority Date: 08/31/1984
• Status: Expired due to Fees

• Current Assignee: University of Dayton
• Original Assignee: University of Dayton
• Inventors: Salyer, Ival O., Griffen, Charles W.
• Primary Examiner(s): McCarthy, Helen M.
• Application Number:
  US06/646,396
• Time in Patent Office: 613 Days
• Field of Search: 126/400, 126/430, 106/109, 106/116, 106/90, 106/96, 52/309.1, 52/309.17, 52/596, 52/612, 52/173 R, 165/104.17, 523/135, 523/206, 524/4, 428/703, 428/913, 428/221, 428/321.5
• US Class Current: 523/206
• 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 2103/0071 Phase-change materials, e.g. latent heat storage materials used in concrete compositions
• CPC Class Codes: C04B 24/32 Polyethers, e.g. alkylphenol polyglycolether
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08L 71/02 Polyalkylene oxides
• CPC Class Codes: F28D 20/023 the latent heat storage material being enclosed in granular particles or dispersed in a porous, fibrous or cellular structure
• CPC Class Codes: Y02E 60/14 Thermal energy storage
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/249997 Encapsulated liquid

Abstract

A cementitious composition comprising a cementitious material and polyethylene glycol or end-capped polyethylene glycol as a phase change material, said polyethylene glycol and said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g; the compositions are useful in making pre-formed building materials such as concrete blocks, brick, dry wall and the like or in making poured structures such as walls or floor pads; the glycols can be encapsulated to reduce their tendency to retard set.

Claims

1. A cementitious composition useful in the manufacture of building materials comprising an inorganic cementitious building material and an end-capped polyethylene glycol dispersed therein as a phase change material, said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g, wherein said end-capped polyethylene glycol is selected from the group consisting of alkoxy-capped polyethylene glycol, urethane-capped polyethylene glycol, and ester-capped polyethylene glycol.

2. The composition of claim 1 wherein said cementitious material is selected from the group consisting of portland cement, gypsum, and plaster of Paris.

3. The cementitious composition of claim 1 wherein said phase change material is a di-end-capped polyethylene glycol.

4. The cementitious composition of claim 3 wherein said phase change material is a methoxy end-capped polyethylene glycol.

5. The cementitious composition of claim 1 wherein said end-capped polyethylene glycol has a molecular weight in the range of about 600 to 1500.

6. The cementitious composition of claim 2 wherein said cementitious material is portland cement and said end-capped polyethylene glycol is present in an amount up to about 5% by weight.

7. The cementitious composition of claim 2 wherein said cementitious material is plaster of Paris and said end-capped polyethylene glycol is present in an amount up to about 20% by weight.

8. The cementitious composition of claim 1 wherein said phase change material is a blend of end-capped polyethylene glycols having distinct melting points such that said blend exhibits two distinct melting points and two distinct heats of fusion.

9. The cementitious composition of claim 8 wherein said blend comprises end-capped polyethylene glycol having a first molecular weight of 1000 or less and an end-capped polyethylene glycol having a second molecular weight and the difference between said first molecular weight and said second molecular weight is at least 2000.

10. The cementitious composition of claim 2 wherein said end-capped polyethylene glycol is incorporated into said cementitious composition in the form of a pellet or granule, said pellet or granule being formed from a polymer material having said phase change material dissolved and/or dispersed therein, wherein said polymer material is other than said end-capped polyethylene glycol and said polymer material isolates the dispersed phase change material from the cementitious composition.

11. The cementitious composition of claim 10 wherein said polymer is a natural or synthetic rubber.

12. The cementitious composition of claim 10 wherein said polymer is selected from the group consisting of nylons, polyesters, polyvinyl alcohol, polyvinyl acetate, ethylene vinylacetate copolymer, butadiene-acrylonitrile copolymer, acrylate and methacrylate rubbers, neoprene, natural rubber, butyl rubber, polybutadiene, butadiene/styrene copolymers and EPDM.

13. The cementitious composition of claim 10 wherein said polymeric material is crosslinked or uncrosslinked.

14. The cementitious composition of claim 13 wherein said phase change material is end-capped by reaction with a polyisocyanate.

19. A bridge deck prepared from the cementitious composition of claim 1.

15. A building block comprising an inorganic cementitious matrix having dispersed therein an end-capped polyethylene glycol as a phase change material, said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g , wherein said end-capped polyethylene glycol is selected from the group consisting of alkoxy-capped polyethylene glycol, urethane-capped polyethylene glycol, and ester-capped polyethylene glycol.

16. The building block of claim 15 wherein said end-capped polyethylene glycol has a molecular weight of about 600 to 1500.

17. A dry wall comprising, gypsum and an end-capped polyethylene glycol dispersed therein as a phase change material, said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g, wherein said end-capped polyethylene glycol is selected from the group consisting of alkoxy-capped polyethylene glycol, urethane-capped polyethylene glycol, and ester-capped polyethylene glycol.

18. The dry wall of claim 17 wherein said end-capped polyethylene glycol has a molecular weight of about 600 to 1500.