Abstract: ：To obtain a composite heat-storage material with good stability，quaternary nitrates/MCM41 porpous composite heat-storage material was prepared with quaternary nitrates as its phase change material and MCM41 as its matrix material. The chemical and thermal stability of the composite material with different mass ratios of quaternary nitrates to MCM41 was verified by 100 thermal cycling experiments. XRD and FT-IR characterization results indicated that the chemical composition of the composite material was unchanged after the experiments and was of positive chemical stability.Its DSC curves showed that the melting point and latent heat of fusion after the thermal cycling experiments were similar with that before the experiments，which confirmed the good thermal stability of the composite material.The density of the composite material was increased with the growth of quaternary nitrate's mass ratio，and its compressive strength was maximum when the mass ratio of quaternary nitrate to MCM41 was 6∶4.Considered the thermal properties，density and compressive strength of the composite material comprehensively，the optimal mass ratio for quaternary nitrate to MCM41 is 6∶4.

Key words: quaternary nitrates, MCM41, phase change, porous composite material, chemical stability, thermal stability, melting latent heat, heat storage