Method for preparing polylactic acid foam material

The invention relates to a preparation method for an expanded material of polylactic acid; the polylactic acid, a tackifying modifier, a chemical inhibitor, a vesicant, a foaming accessory ingredient, a abscess stabilizer and a parting agent are mixed under high temperature according to a certain proportion to obtain a basic mixture; then the basic mixture is arranged in a die to carry out moulding foaming on a vulcanizing machine with a certain temperature and a certain pressure to manufacture the foaming material of polylactic acid. The foaming material of polylactic acid manufactured by the method of the invention has excellent performances of being biodegradable, controllable density, easy processing as well as good barrier property, has similar foaming shaping performance and shock-absorbing capacity with polystyrene, can replace the foaming material of polystyrene, can be used as the materials for heat isolating, sound isolating and shock absorption and has broad application in the fields of cushion packaging, transportation, electric apparatus, refrigeration, agriculture and forestry and gardening.