DUAL PHASE CHANGE MATERIAL LIQUID SUSPENSION AND METHOD OF MAKING THE SAME

1 . A phase change material comprising:

a first phase change material in liquid form having a first phase change temperature;

a second phase change material in microencapsulated form having a second phase change temperature;

a thickening agent; and

a surfactant,

wherein said first and second phase change materials, said thickening agent and said surfactant are blended in a homogenous mixture and heated for a period of time.

2 . The phase change material of claim 1 wherein said first phase change material is selected from the group consisting of: water-based PCMs; plant-based organic PCMs, paraffin based PCMs and salt hydrate based PCM's.

3 . The phase change material of claim 1 wherein said second PCM material comprises a plant-based organic PCM microencapsulated in an acrylic shell.

4 . The phase change material of claim 2 wherein said second PCM material comprises a plant-based organic PCM microencapsulated in an acrylic shell.

5 . The phase change material of claim 1 wherein said first phase change material has a phase change temperature of about 9.5° C.

6 . The phase change material of claim 1 wherein said second phase change material has a phase change temperature of about 37° C.

7 . The phase change material of claim 5 wherein said second phase change material has a phase change temperature of about 37° C.

8 . The phase change material of claim 2 wherein said liquid PCM comprises an organic ester.

9 . The phase change material of claim 4 wherein said liquid PCM comprises an organic ester.

10 . The phase change material of claim 1 wherein said surfactant is polysorbate 80.

11 . The phase change material of claim 4 wherein said surfactant is polysorbate 80.

12 . A method for making a dual phase change material liquid suspension comprising the steps of:

providing a first phase change material in liquid form having a first phase change temperature;

providing a second phase change material in microencapsulated form having a second phase change temperature;

providing a thickening agent;

providing a surfactant;

stirring the first phase change material;

adding the thickening agent to the first phase change material and stirring until evenly dispersed;

heating the first change material and thickening agent to a predetermined temperature while stirring;

adding the second phase change material while stirring and maintaining said temperature;

adding the surfactant while stirring and maintaining said temperature; and

cooling to ambient temperature.

13 . The method of claim 12 wherein the predetermined temperature is about 60° C.

14 . The method of claim 12 wherein said surfactant is polysorbate 80.

15 . The method of claim 13 wherein said surfactant is polysorbate 80.

16 . A method for making a dual phase change material liquid suspension comprising the steps of:

providing a first phase change material in liquid form having a first phase change temperature;

providing a second phase change material in microencapsulated form having a second phase change temperature;

providing a thickening agent;

providing a surfactant;

stirring the first phase change material;

adding the thickening agent to the first phase change material and stirring until evenly dispersed;

adding the surfactant and stirring until evenly dispersed;

adding the second phase change material and stirring until evenly dispersed;

heating the dispersed materials to predetermined temperature while stirring;

maintaining said temperature while stirring for a period of time and cooling to ambient temperature.

17 . The method of claim 16 wherein the predetermined temperature is about 60° C.

18 . The method of claim 16 wherein said surfactant is polysorbate 80.

19 . The method of claim 17 wherein said surfactant is polysorbate 80.