Test 3 shows a better distribution of microcapsules of PCM throughout the polyurethane foam than the other manufacturing processes commented above, see Figure 6 (c) and (d).

Figure 8 Thermal performance test of the reference sandwich panel and sandwich panel with PCM (Test 3)

4. Discussion

Thanks to the high thermal storage capacity of microencapsulated PCM, they can confer high thermal inertia to the sandwich panels. Related to test 1 and test 2 were observed problems with the adhesion test, but this problem can be solving if the process is industrialized by the company, as well as, test 2 could improve its thermal behaviour. Another option was studied using the macroencapsulation (rigid container) (Carbonari et al [14]), so that, it was added to one side of the sandwich panel.

In test 3 problem of adhesion test was solved, but a new effect is observed, this time the distribution of the microcapsules is homogeneous, but microcapsules took the air spaces that have the polyurethane foam, and the effect of the PCM is overlap by a possible increase in thermal conductivity.

5. Concluding remarks

The goal of this study was to demonstrate the feasibility to use the microencapsulate PCM (Micronal BASF) in sandwich panels to increase its thermal inertia, and therefore, reduce the energy demand of the final buildings. The results shown above include different manufacture processes and the results obtained with these experiments were very promising. The possibility to adapt this technology to manufacture panels allows their installation on ceilings and walls.

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