A series of multi-functionality polyester polyols (MAP) were synthesized successfully by using a renewable resource of malic acid and 1,6-hexanediol via esterification. The chemical structure of MAP was characterized by proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared (FTIR), gel permeation chromatography (GPC) as well as acid and hydroxyl values. Then it was used to prepare rigid polyurethane foams (RPUFs). The results suggested that MAP based RPUFs showed lower density (37?39 kg/m3), compressive
strength (154?156 kPa) and better insulation (0.019?0.025 W/(m·K)) than that of the commercial petrochemical polyol. Moreover, thermal degradation behavior of MAP based RPUF were demonstrated by thermogravimetric analysis (TGA), thermogravimetric analysis connected with Fourier transform infrared spectrometry (TG-FTIR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) in detail. It indicated that as a bio-resource
polyol, MAP could totally substitute petrochemical polyol to prepare RPUF with a good comprehensive performance.