Graphene oxide/polyurethane-based solid–solid phase change materials with enhanced mechanical properties.

Graphene oxide (GO) crosslinked polyurethane-based solid–solid phase change materials, composed by polyethylene glycol (PEG) and hexamethylene diisocyanate biuret (HDIB), were fabricated in-situ polymerization. GO sheets could support the excellent solid framework at 100 °C and prevent the leakage of melt in synergy with HDIB by physical and chemical crosslinking network. Meanwhile, GO sheets act as heterogeneous nucleation agents that make the crystallization temperature of system rise to 34.0 °C from 24.8 °C with 14.5 wt‰ GO. Whereas, GO have little effect on the latent heat, which may be an offset of the nucleation and confinement. Besides, the tensile strength increased to 21. 7 from 10.2 MPa with 14.5 wt‰ GO and Young’s modulus increased to 471.5 from 180.1 MPa for 44.6 wt‰ one. Also, the strain at break has a slight promotion within 14.5 wt‰ GO. The synthesized system would be potential to be applied in thermal energy storage fields. [ABSTRACT FROM AUTHOR]