Sonochemical Synthesis of Maleated Rosin*

The cycloaddition reaction of rosin and maleic anhydride under ultrasonic irradiation has been investigated. The results show that both isomerization and Diels-Alder cycloaddition reactions were accelerated remarkably. The sonochemical reaction reached equilibrium in 5–10 min at 110°C, comparing with regular synthesis of 4–5 h over 180°C.