Organocatalytic depolymerization of poly(3-hydroxybutyrate) to crotonic acid

Utilizing end-of-life poly(3-hydroxybutyrate) (PHB) as a carbon source for the production of value-added chemicals has attracted increasing interest in recent years. In this report, an organocatalytic pyrolysis method was explored for chemical recycling of PHB into trans-crotonic acid (CA). Under relatively mild conditions and through the promotion of organic base catalysts, the CA was recovered with high efficiency and yield. The effect of reaction conditions on the depolymerization process, such as types of catalysts, solvent polarity, temperature, and molar equivalents of PHB to catalyst, was investigated in detail. This work is the first to achieve the pyrolysis of PHB using organic base catalysts, which provides a green and efficient option for plastic degradation and promotes the development of circular plastic economy.