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Phase change materials (PCMs) have been a main topic in research in recent years, but although the information is quantitatively enormous, it is widely spread in the literature. The storage of latent heat in organic matters could provide a great density of energy storage with a small temperature difference between storing and releasing heat. Six kinds of organic matters, including tetradecane, lauric acid, methyl laurate, decanoi, decanoic acid and ethyl salicylate were selected as experimental materials for development of phase-change coolant for non-freezing cold chain. The thermodynamic formula was used to calculate the onset temperature and latent heat of designed compounds. DSC and stability tests were used for the selected compounds with the appropriate onset temperature and high latent heat. DSC was used commonly and it was the most authoritative method of determining phase change properties until now. The results showed that decanoic acid/methyl laurate, decanoic acid/decanoic, lauric acid/tetradecane, methyl laurate/lauric acid had onset temperature range of 0~4℃, latent heat of 150~210J/g, which met the requirement of non-freezing cold chain at low temperature. In these PCMs, lauric acid/tetradecane (mass ratio 3.12∶96.88) had the optimal performance, with onset temperature of 4.03℃ and phase change latent heat of 207.05J/g;lauric acid/tetradecane (mass ratio of 6.17∶93.83) and decanoic acid/tetradecane had a good performance in thermal properties and cost, with onset temperature of 3.89℃ and 3.19℃ and phase change latent heat of 192.61J/g and 189.21J/g, respectively;decanoic acid/decanoic (mass fraction of decanoic acid was 34.51%~47.24%) was selected for its relatively wide range of adjustable onset temperature. The above PCMs owned broad application prospects.