Starch-based fully-degradable PBAT master batch capable of being mixed for use as well as preparation method and application thereof

The invention discloses a starch-based fully-degradable PBAT master batch capable of being mixed for use and a preparation method and an application thereof. The starch-based fully-degradable PBAT master batch comprises the following components in percentage by mass: 30-50% of starch, 5-15% of glycerol, 40-60% of PBAT, 1-5% of a heat stabilizer, 0.1-1% of a lubricant, 1-5% of an auxiliary plasticizer, 0.1-0.5% of an antioxidant and 0.1-0.5% of a chain extender. The starch is plasticized by adding glycerol, an auxiliary plasticizer and the like, so that the starch has the possibility of thermoplastic processing; the bio-based material starch is introduced on the basis of the whole bio-based biodegradable material PBAT, the requirement of complete degradation is met after composite modification, meanwhile, the mechanical property of the bio-based PBAT resin is enhanced, and the cost is reduced; the starch-based fully-degradable PBAT master batch prepared by the invention can be mixed with a PBAT raw material an