Ultralight high-flame-retardant biodegradable PLA (polylactic acid) foam and preparation process thereof

The invention relates to the technical field of PLA foam, in particular to ultralight high-flame-retardant biodegradable PLA foam and a preparation process thereof. The preparation method comprises the following steps: S1, compounding RDP, lignin, APP and silicon dioxide aerogel to obtain a flame-retardant system; s2, PLA, PBAT, a flame-retardant system and an epoxy chain extender are mixed, and a mixed sample is obtained after the reaction is finished; s3, putting the mixed sample into a forming device for forming to obtain a formed sample; s4, performing supercritical foaming on the formed sample in a carbon dioxide atmosphere to obtain a foamed sample; and step S5, cooling and shaping the foamed sample to obtain the ultra-light high-flame-retardant biodegradable PLA foam. The PLA foam prepared by the invention is low in density, low in heat conductivity coefficient, good in flame retardance and fully biodegradable, and can be widely applied to the fields of packaging, heat preservation and shock absorption