| abstract |
The present invention relates to the production of polylactide. The lactide production and purification stage uses an aqueous solution of lactic acid or its derivatives as an initial raw material, evaporates water, forms oligomers, depolymerizes to obtain lactide, and concentrates and crystallizes the crude lactide product. The obtained lactide is obtained, the remaining fraction resulting from crystallization is subjected to an aqueous treatment, and the purified and / or previously purified lactide is polymerized in the presence of a catalyst in a molding machine to obtain polylactide. In another embodiment, an aqueous treatment is performed before crystallization. |