abstract |
A method of producing a poly(lactic acid) resin includes carrying out direct polycondensation using lactic acid as a main raw material to prepare a crystallized prepolymer having a weight average molecular weight of 5,000 to 25,000, an enthalpy of fusion ΔHm of 50 to 65 J/g and an acid value A mol/ton satisfying (1) below: n 450/(Mw/10,000−0.14)<A<950/(Mw/10,000−0.14) (1)n n (wherein Mw represents weight average molecular weight of the crystallized prepolymer); and subjecting the crystallized prepolymer to solid-phase polymerization. |