The present application relates to the technical field of
toughening and
flame-retardant modification of
polylactic acid, and in particular to a modifier with
toughening and
flame-retardant effects, a preparation method thereof and application in high molecular weight
polylactic acid. An olefin-based
monomer is polymerized by addition to form an
elastomer polymer with high molecular weight, which is then reacted with a soft
monomer of acrylic ester in a uniform
emulsion A to form a three-dimensional crosslinked
network structure, and the molecular chain formed is an amorphous high-elasticity molecular segment, which has good
toughness. The hard
monomer of acrylic ester in the uniform
emulsion B grafted inhibits
diffusion and arrangement of the molecular segment, thereby achieving a
toughening effect. Meanwhile, the hard monomer of acrylic ester reacts with
lignin in situ in a
bulk polymerization reaction. Since
lignin has good
carbonization in the
combustion process, it can prevent the material from continuing to burn, and thus has good
flame retardancy, can be used as a flame retardant for high
molecular materials, expands the application field of
lignin and improves the
utilization rate of lignin.