The present invention relates to a preparation method of fully biodegradable heat-resistant polylactic acid material, which belongs to the field of biodegradable polymer materials. The operation steps are as follows: dry and mix high molecular weight polylactic acid, mesh structured micro nano cellulose powder, and polyethylene glycol; Place the dried mixed raw materials in an internal mixer according to the quality ratio to obtain a pre dispersed mixture; Add the pre dispersed mixture into a twin-screw extruder, melt and extrude at 170-190 ℃, cool the extruded material, collect the pellets, and obtain a fully biodegradable heat-resistant polylactic acid material; The heat-resistant deformation Vicat softening point temperature of the fully biodegradable heat-resistant polylactic acid material is 145-158 ℃, the crystallinity is 45-56%, the tensile strength is 32-42Mpa, and the elongation at break is 12-23%. The present invention achieves a multi interlocking network system through formula control to suppress the movement of polylactic acid molecular chains and promote the folding of polylactic acid chains into a dense crystalline structure by the mobile phase, achieving excellent high heat resistance through a dual mechanism.
Country Code: CN
Application Number: CN202210585854.5
