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A novel biodegradable solid–solid phase change heat storage composite materials (GO-PBSEG) were synthesized by in situ polymerization reaction of high molecular weight poly(ethylene glycol) (PEG4000) with succinic acid, 1,4-butanediol (BD) and graphite oxide (GO). PEG was used as a working substance in GO-PBSEG composite materials. To characterize the resulting product, Fourier transform infrared spectroscopy, NMR spectrometer, differential scanning calorimetry, thermal constant analyzer, polarization optical microscopy measurements and scanning electron microscopy were employed to investigate the structure, thermal properties, crystalline behavior and enzymatic degradation of phase change materials. The experimental results indicated that the GO-PBSEG composite materials showed typical solid–solid phase transition properties, and the exothermic phase change enthalpy of PEG unit reached 64.8 J g−1. With the increase in GO content, the thermal conductivity properties of composite materials were improved, and the enzymatic degradation rate gradually increased. POM observations indicated that the 1.0 mass% GO-PBSEG sample had the largest spherulites and the lowest nucleation ability. [ABSTRACT FROM AUTHOR]

In this study, graphene oxide (GO) was prepared by the modified Hummers' method and poly(butylene succinate-co-neopentylglycol succinate)/graphene oxide (GO–PBNPGS) nanocomposites were synthesized via in situ polymerization with a series of GO contents (from 0.01 to 0.10 mass%). The GO was characterized by Fourier transform infrared spectrum, atomic force microscopy and wide-angle X-ray diffractometry. The non-isothermal crystallization kinetics and crystalline morphology of the neat PBNPGS and its nanocomposites were analyzed by differential scanning calorimetry and polarized optical microscopy (POM), respectively. The results showed that GO was prepared successfully and dispersed in PBNPGS uniformly during the experimental process. The non-isothermal crystallization kinetics was characterized using Avrami equation modified by Jeziorny. The experimental results indicated that the non-isothermal crystallization behavior of the GO–PBNPGS was influenced by the GO content and cooling rate, the crystallization rate first increased and then decreased with an increase in GO content. Therefore, it was expected that the GO could accelerate the crystallization process. POM observations indicated that GO served as an effective nucleating agent for the crystallization of GO–PBNPGS when 0.10 mass% GO was added, and 0.05 mass% GO in PBNPGS had the largest spherulites and the lowest nucleation ability. In addition, the experimental data also showed that the biodegradation rate increased with the increasing of GO content, with a significant rate of degradation occurring in the composite sample with 0.10 mass% GO content. [ABSTRACT FROM AUTHOR]