Abietic acid, a major component of rosin, was isolated by means of reaction-crystallization strengthened with ultrasonic waves, and then it was characterized by ultraviolet visible spectra (UV), gas chromatography-mass spectra (GC-MS), and lH nuclear magnetic resonance spectra ^H-NMR), respectively. The constant-volume combustion heat of abietic acid was determined to be -11441.46 kJmol"1 by GR-3500B2-type oxygen bomb calorimeter, and based on the thermodynamic principle, the standard molar combustion enthalpy and molar enthalpy of formation of abietic acid were calculated to be -11457.57 kJ^mol"1 and -699.43 kJ-mol"1. The specific optical rotation of the abietic acid was determined to be -105.4?by using a 341LC polarimeter. The melting point and the molar fusion enthalpy of abietic acid were determined to be 450.89 K and 19.44 kJ-moP1 via differential scanning calorimetry (DSC), and the molar fusion entropy of abietic acid was calculated to be 43.11 Jmor'-K"1 according to thermodynamic principle.%采用超声波强化反应-结晶耦合的方法单离松香主要成分枞酸,测定了枞酸的恒容燃烧热、熔点和比旋光度,通过UV、GC-MS、NMR对枞酸进行分析鉴定.结果表明,用GR-3500B2氧弹式量热计测定枞酸的恒容燃烧热为-11441.46 kJ·mol-1,计算出枞酸的标准摩尔燃烧焓和标准摩尔生成焓分别为-11457.57 kJ·mol-1和-699.43 kJ·mol-1;用341LC plus微量旋光仪测定枞酸的比旋光度为-105.4°；用DSC 6200差示扫描量热仪测得枞酸的熔点和熔化焓分别为450.89 K和19.44 kJ·mol-1,计算出枞酸的熔化熵为43.11J·mol-1·K-1.
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