The invention discloses a simple preparation method of a high-
starch-content, high-strength and low-cost biological
polyester film bag material, and belongs to the field of biodegradable high-
molecular materials. PBAT, high-molecular-weight
polylactic acid,
starch, a compatible modifier, a biological chain
extender and an
antioxidant are put into a mixing mill to be mixed at a high speed, and pre-dispersed mixed granules are obtained; the preparation method comprises the following steps: adding the raw materials into an internal mixing and
extrusion integrated reverse twin-screw extruder, firstly melting and internal mixing for in-situ reaction, then starting
extrusion, cooling the extruded material by
air cooling, then
cutting and collecting granules, and taking an amphiphilic block
copolymer polypropylene glycol-
polyethylene glycol-
polypropylene glycol (PPG) as a modifier, the use amount of
polylactic acid is small, the
starch content is high, plasticizing is not needed, the components are easy to obtain, the multi-phase interface
permeation adhesion is high, the
system is uniform, the method is simple, and the cost is low; the
biodegradable plastic has the advantages of
toughness of PBAT, strength of PLA, low price of starch and
compatibilization and reinforcement of amphiphilic blocks, and is suitable for
processing of biodegradable film bags, dustproof nets, plastic parts and other
bioplastic products.