caa a22 4500 463229185 CHVBK 20180405153236.0 cr unu---uuuuu 170326e20070701xx s 000 0 eng 10.1007/s10853-006-0884-z doi (NATIONALLICENCE)springer-10.1007/s10853-006-0884-z Crystalline-amorphous phase transition of hyperbranched polyurethane phase change materials for energy storage [Elektronische Daten] [Qi Cao, Pengsheng Liu] Hyperbranched polyurethane solid-solid phase change material (HB-PUPCM) has been prepared via a two-step process. The phase transition behaviors and morphologies of these HB-PUPCM films were investigated using differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and polarizing optical microscopy (POM). PEG soft segment in the polyurethane was found to be crystalline at room temperature. However, when the temperature was raised to PEG's melting point, polyurethane did not melt into the liquid state as in the case of pure PEG but changed to an amorphous solid state. In HB-PUPCM, PEG's molecules probably are tied to the hard segment chain so strongly by the chemical bonds that they cannot change to a liquid state but change to the amorphous state in the transition processing. Springer Science+Business Media, LLC, 2007 Cao Qi College of Chemistry, Xiangtan University, 411105, Xiangtan, Hunan Province, P.R. China aut Liu Pengsheng College of Chemistry, Xiangtan University, 411105, Xiangtan, Hunan Province, P.R. China aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/14(2007-07-01), 5661-5665 0022-2461 42:14<5661 2007 42 10853 https://doi.org/10.1007/s10853-006-0884-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-0884-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Cao Qi College of Chemistry, Xiangtan University, 411105, Xiangtan, Hunan Province, P.R. China aut NATIONALLICENCE 700 1- Liu Pengsheng College of Chemistry, Xiangtan University, 411105, Xiangtan, Hunan Province, P.R. China aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/14(2007-07-01), 5661-5665 0022-2461 42:14<5661 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer