Heat storage materials

• US 4,545,916 A
• Filed: 07/12/1983
• Issued: 10/08/1985
• Est. Priority Date: 07/15/1982
• Status: Expired due to Fees

• Current Assignee: IC Gas International Limited
• Original Assignee: IC Gas International Limited
• Inventors: Chalk, Christine D., Hayman, Cecil
• Primary Examiner(s): Lieberman, Paul
• Assistant Examiner(s): Wax, Robert A.
• Application Number:
  US06/513,097
• Time in Patent Office: 819 Days
• Field of Search: 252/70
• US Class Current: 252/70
• CPC Class Codes: C09K 5/063 Materials absorbing or liberating heat during crystallisation; Heat storage materials

Abstract

The heat storage material, which undergoes reproducible transition in the range 66° to 74° C., comprises sodium pyrophosphate decahydrate (Na₄ P₂ O₇.10 H₂ O) dispersed throughout an open cell polymeric matrix which is stable in an aqueous medium at 80° C.

In use (for example, for space heating) the material is alternately heated to above 80° C. and cooled below its transition temperature with evolution of heat.

Claims

1. A heat storage material which comprises sodium pyrophosphate decahydrate dispersed throughout an open cell polymeric matrix which is stable in an aqueous medium at 80°

C., the polymeric matrix being present in a minor amount.

2. A heat storage material according to claim 1, in which the polymeric matrix comprises a water-swollen cross-linked polymer hydrogel.

3. A method of heat exchange which comprises alternately heating a material according to claim 1 or 2 to a temperature of above 80°

C., and allowing said material to cool below the transition temperature thereof.