Preparation method of full bio-based polyamide

The invention belongs to the technical field of polymers, and provides a preparation method of full-bio-based polyamide. The preparation method comprises the following steps: mixing full-bio-based polyamide salt with water, concentrating, dehydrating and concentrating, continuously heating, entering a prepolymerization stage and a solid-phase tackifying stage, carrying out the two stages under closed conditions, not discharging water vapor, ensuring the stability of binary acid and diamine in a system, avoiding the loss of diamine, and obtaining polyamide after the reaction is stable. The method has the advantages of high repeatability and high stability, the terminal group content difference of polyamides of different production batches under the same production condition is small, and the maximum deviation value of the terminal amino group is less than or equal to 10%. The method is particularly suitable for intermittent production equipment, and the equipment investment cost is greatly reduced. 本发明属于聚合物技术领