Polyolefin composites containing a phase change material

• US 5,053,446 A
• Filed: 03/03/1989
• Issued: 10/01/1991
• Est. Priority Date: 11/22/1985
• Status: Expired due to Term

• Current Assignee: University of Dayton
• Original Assignee: University of Dayton
• Inventors: Salyer, Ival O.
• Primary Examiner(s): Lilling, Herbert J.
• Application Number:
  US07/319,835
• Time in Patent Office: 942 Days
• Field of Search: 252/70, 428/402, 523/205, 524/8, 524/409, 524/411, 524/464, 524/476-478
• US Class Current: 524/8
• CPC Class Codes: C08K 3/36 Silica
• CPC Class Codes: C08K 5/01 Hydrocarbons C08K5/0091 takes precedence
• CPC Class Codes: C08K 5/14 Peroxides
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 2312/00 Crosslinking
• CPC Class Codes: C08L 2312/06 by radiation
• CPC Class Codes: C08L 91/06 Waxes
• 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: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A composite useful in thermal energy storage, said composite being formed of a polyolefin matrix having a phase change material such as a crystalline alkyl hydrocarbon incorporated therein, said polyolefin being thermally form stable; the composite is useful in forming pellets, sheets or fibers having thermal energy storage characteristics; methods for forming the composite are also disclosed.

Claims

1. A composite useful in thermal energy storage, said composite being thermally form stable and being formed of a first material and a second material which is different from said first material, and which has a melting point less than said first material, but which is compatible with said first material, said first material comprising a crosslinked or uncrosslinked polyolefin matrix which serves as a containment means for said second material, and said second material comprising a crystalline alkyl hydrocarbon phase change material having a heat of fusion greater than about 30 cal./g. and a melting and a freezing point in the range of 0 to 80°

C., said second material being contained within the matrix of said first material, thereby forming said composite.

2. The composite of claim 1 wherein said polyolefin is polyethylene, polypropylene, polybutene, crystalline polystyrene, or poly (4-methyl-pentene-1).

3. The composite of claim 2 wherein said polyolefin is crosslinked high density polyethylene.

4. The composite of claim 3 wherein said high density polyethylene is crosslinked to such a degree that said polyolefin matrix is form stable and said polyolefin matrix is capable of absorbing at least 10% by weight of said phase change material.

5. The composite of claim 1 wherein said composite is in a form selected from the group consisting of a pellet, a film or sheet, and a fiber or strand.

6. The composite of a claim 1 wherein said phase change material is imbibed into said polylefin matrix by immersing said polyolefin matrix into a hot melt of said phase change material at a temperature higher than the crystalline melt point of said polyolefin.

7. The composite of claim 1 wherein aid polyolefin is crosslinked high density polyethylene, said phase change material is a crystalline alkyl hydrocarbon and said composite is in pellet form.

8. The composite of claim 5 wherein said composite is in pellet form and further including a non-polymeric cemetitious material into which said composite in pellet form is dispersed.

9. The composite of claim 8 wherein said polyolefin is cross-linked higher density polyethylene, said phase change material is a crystalline alkyl hydrocarbon, and said cementitious material is in the form of gypsum board.