Abstract: Water dispersible rosin-based polyester polyol (WDRPP) was prepared through the method of first fractional melting reaction and then reflux, using maleopimaric anhydride (MPA), neopentyl glycol (NPG), trimethylolpropane (TMP), isophthalic acid (IPA), adipic acid (AA) and 5-sulfoiso-phtalic acid mono sodium salt (5-SSIPA) as raw materials.Effects of reaction time, the amount of catalyst, n(-OH):n(-COOH) and the amount of hydrophilic monomer on the reactions were investigated.The products were characterized by fourier transform infrared spectroscopy (FT-IR) and ¹³ C NMR.The heat resistance of WDRPP was studied using thermogravimetric analyzer (TG).The thermal degradation kinetic data were analyzed using Coats-Redfem method, and the kinetic parameters were obtained.The results showed that WDRPP with excellent thermostability and the WDRPP dispersion with good stability were obtained when reaction time was 5.5 h(melting reaction time of 3 h and reflux time of 2.5 h), the amount of catalyst was 0.10%, n(-OH):n(-COOH) was 1.4:1, and the amount of hydrophilic monomer was 2.86%, respectively.It was found that the temperature at maximum weight loss rate was 406.7℃, the reaction activation energy of pyrolysis was 64.65 kJ/mol, and the linear curves of thermal degradation kinetics fitted well (R²=0.997 3). This indicated that the thermal degradation process of WDRPP followed the law of first-order kinetic reaction.FT-IR and ¹³C NMR results demonstrated that WDRPP was prepared successfully.

Key words: water dispersible, rosin-based polyester polyol, heat resistance, Coats-Redfem method