▎ 摘　　要

NOVELTY - Bio-based flame retardant comprises 50-70 pts. wt. phytic acid, 60-70 pts. wt. hydroxyethyl hexahydrotriazine, 20-40 pts. wt. carbon source, 2-5 pts. wt. synergist, 10-15 pts. wt. catalyst, 5-10 pts. wt. magnesium chloride, and 100-400 pts. wt. water, where the carbon source is graphene oxide and/or graphite oxide. USE - The bio-based flame retardant is used for preparing polylactic acid film (claimed). ADVANTAGE - The bio-based flame retardant effectively increases the thickness and heat resistance of the carbon layer, improves the flame retardant performance of the entire system, does not contain melamine, which is more beneficial to be used in the food field. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the bio-based flame retardant comprising (a) mixing the aqueous solution of hydroxyethyl hexahydrotriazine and phytic acid to obtain a mixed solution, (b) heating mixed solution to 80-90degrees Celsius, adding catalyst under stirring condition, carrying out reaction, obtaining reaction solution, (c) mixing the reaction solution with the dispersion of the carbon source, and reacting at 60-70degrees Celsius to obtain a flame retardant stock solution, (d) adding a synergist and magnesium chloride to the flame retardant stock solution, filtering and drying to obtain the product.