Difunctional olefin block copolymer/paraffin form-stable phase change materials with simultaneous shape memory property

In this work, a novel sort of form-stable phase change materials (FSPCMs) which possesses simultaneously the shape memory function was designed and prepared. The FSPCMs consist of paraffin with melting point of approximately 53 °C as a latent heat storage material and olefin block copolymer (OBC) as a supporting material. With mass percentage of paraffin up to 40 wt%, the FSPCMs exhibit good shape stability until temperature approaches 90 °C as shown by visual photographs, and this result is confirmed by dynamic mechanical analysis. At the same time, composites with 40 wt% paraffin also maintain the excellent mechanical property of OBC and exhibit large elongation at break as well as similar tensile stress, insuring excellent tenacity and deformation ability. The results of shape memory testing demonstrate that the composites possess good shape memory property, with nearly complete shape fixing and recovery. Compared with other reported FSPCMs, this material can be both temperature-controlled and temperature-sensitive, and may show advantages in some advanced applications such as intelligent textile. The diversity of paraffin endows the composites with flexibility of design for applications with wide range of temperatures. Considering the inexpensive sources and easy processing, this work may open up opportunities to produce difunctional FSPCMs in the industrial field.