Preparation of PAA/DD/KNE composites, characterization and determination of thermal energy storage properties

In this thesis study, new types of shape-stabilized phase change materials (SSPCM) with improved thermal conductivity were produced by using polyacrylic acid (PAA), dodecanol (DD), carbon nanofiber (CNF) by solvent casting technique. In the study, DD with latent heat energy storage (LHTES) property was chosen as a phase change material (PCM) as PAA polymer was used as main supporting material. CNF was used to enhance thermal conductivity value and heat storage/release rate; besides, increase the confinement rate of DD in PAA. In this context, the produced DD/PAA composites were doped with 4wt% and 10wt% CNF. The confinement ability of PAA due to its cross-linked network structure allowed the impregnation DD as high as 70wt% without observing any PCM leakage behavior. The FTIR and XRD findings confirmed that there was no chemical bonding between the components DD/PAA or DD/PAA/CNF composites. The DSC analysis showed that the PAA/DD (70% wt)/CNF(10%wt) composite can store a latent heat of 157.03 J/g at a phase change temperature of 18.04 °C. The TGA results revealed that this composite has excellent resistance to thermal degradation up to 115 °C. It was observed that the CNF doping process caused a significant increase in the thermal conductivity of the DD/PAA composite and consequently leaded to a significant reduction in the heat charging/discharging times of the composite. Based on all of the experimental, it was concluded that especially PAA-based and CNF-doped SSPCMs can be evaluated as energysaving material for heat management of buildings.