The world resources can no longer support both the increasing human population and the effects resulting from the activities of this population. For this reason, the sustainable development, which considers the needs of the environment and aims to increase the welfare level of people, attracts more and more attention. For sustainable development, energy saving materials play a crucial role. Phase change materials (PCM’s) are special types of an energy saving materials. In this book, thermal and mechanical properties of paraffin, polyethylene glycol and woods metal filled unsaturated polyesters are characterized.

I hope this book will clarify many questions in the minds.

- Assoc. Prof. Gökhan ÇAYLI