Radiative properties of polymer coatings from the point of view of energy conservation

The importance and contribution of the radiative properties of polymer-based exterior building materials to energy conservation are discussed in this work. The high hemispherical absorptances and the high monochromatic absorptances between 3000–4200 Å wavelengths of all polymers are introduced. We have tried to determine the reason for the high absorptances and examined the possibility of reducing this property. This is especially necessary for buildings in a hot climate which are covered with polymers with high absorptances and need excessive energy for cooling. Magnified surface photographs were taken and atomic compositions of three polymers and one ceramic samples were determined by scanning electron microscopy. The bond types of polymers and the dissociation energy of these bonds were theoretically examined. The results indicate that the high absorptance is a result of the breaking of single bonds especially between CO, CO and CH. In the domain of this study it was impossible to prevent the bond cleavage. Therefore it is advisable to avoid the use of carbon-based polymer exterior coatings in hot climates.