Preparation method of high-barrier and high-dispersity PET black master batch

The invention provides a preparation method of a high-barrier and high-dispersity PET black master batch, which comprises the following steps: adding 12-23% of polyethylene terephthalate into 18-57% of mixture particles of polytetramethylpentene and polybutylene terephthalate in percentage by mass, and carrying out melt blending on the mixture particles and 3.5% of polyol ester, thereby obtaining the high-barrier and high-dispersity PET black master batch. The preparation method comprises the following steps: adding a liquid-phase medium into a PET black master batch mixture, carrying out wet grinding on carbon black, carrying out preliminary dispersion to enable the particle size of the carbon black to be 16-18nm, separating out the carbon black and the liquid-phase medium after the particle size is ground to reach the standard, preparing the mixed PET black master batch mixture into master batch through a twin-screw extruder, and carrying out extrusion granulation to obtain the master batch, so that the dis